Journals
Authors:
Da Silva J.P. (Autor de correspondencia); Hermoso V.; Lopes-Lima M.; et al.
Journal:
GLOBAL CHANGE BIOLOGY
ISSN:
1354-1013
Year:
2024
Vol.:
30
N°:
e17169
Climate change may lead to range shifts, and barriers to such displacements may result in extirpations from previously suitable habitats. This may be particularly important in freshwater ecosystems that are highly fragmented by anthropogenic obstacles, such as dams and other smaller in- stream barriers. Conservation planning in freshwaters should consider the dynamic effects of climate change and the ability of species to cope with it. In this study, we developed a framework for incorporating climate-driven dispersal barriers into conservation planning taking into account the medium and long- term impacts of climate change and species with obligatory interactions. Given that freshwater mussels (Bivalvia: Unionida) are a group of highly threatened organ -isms dependent on fish hosts to complete their larval development and dispersal, we used Marxan to prioritize areas for their joint conservation in the Iberian Peninsula as a case study. We tested two connectivity scenarios between current and future habi -tats, (i) unlimited dispersal capacity and (ii) dispersal constrained by artificial barriers,and also identified priority translocation areas for species that were unable to dis -perse. Accounting for the effects of climate change on species distributions allowed the identification of long- term conservation areas, but disregarding artificial barriers to dispersal may lead to unrealistic solutions. Integrating the location of barriers al -lowed the identification of priority areas that are more likely to be colonized in the fu-ture following climatic shifts, although this resulted in an additional loss of six to eight features (~5%¿7%) compared to solutions without dispersal constraints. Between 173 and 357 artificial barriers (~1.6%¿3.3%) will potentially block species dispersal to irre -placeable planning units. Where removal of artificial barriers is unfeasible, conserva-tion translocations may additionally cover up to eight additional features that do not meet conservation targets due to dispersal constraints. This study highlights the chal -lenge of identifying protected areas to safeguard biodiversity under climate change.
Authors:
Oficialdegui, F. J. (Autor de correspondencia); Zamora-Marín, J. M.; Guareschi, S.; et al.
Journal:
SCIENCE OF THE TOTAL ENVIRONMENT
ISSN:
0048-9697
Year:
2023
Vol.:
869
pp.
161798
As the number of introduced species keeps increasing unabatedly, identifying and prioritising current and potential Invasive Alien Species (IAS) has become essential to manage them. Horizon Scanning (HS), defined as an exploration of potential threats, is considered a fundamental component of IAS management. By combining scientific knowledge on taxa with expert opinion, we identified the most relevant aquatic IAS in the Iberian Peninsula, i.e., those with the greatest geographic extent (or probability of introduction), severe ecological, economic and human health impacts, greatest difficulty and acceptability of management. We highlighted the 126 most relevant IAS already present in Iberian inland waters (i.e., Concern list) and 89 with a high probability of being introduced in the near future (i.e., Alert list), of which 24 and 10 IAS, respectively, were considered as a management priority after receiving the highest scores in the expert assessment (i.e., top-ranked IAS). In both lists, aquatic IAS belonging to the four thematic groups (plants, freshwater invertebrates, estuarine invertebrates, and vertebrates) were identified as having been introduced through various pathways from different regions of the world and classified according to their main functional feeding groups. Also, the latest update of the list of IAS of Union concern pursuant to Regulation (EU) No 1143/2014 includes only 12 top-ranked IAS identified for the Iberian Peninsula, while the national lists incorporate the vast majority of them. This fact underlines the great importance of taxa prioritisation exercises at biogeographical scales as a step prior to risk analyses and their inclusion in national lists. This HS provides a robust assessment and a cost-effective strategy for decision-makers and stakeholders to prioritise the use of limited resources for IAS prevention and management. Although applied at a transnational level in a European biodiversity hotspot, this approach is designed for potential application at any geographical or administrative scale, including the continental one.
Authors:
Oficialdegui, F. J. (Autor de correspondencia); Zamora-Marín, J. M.; Guareschi, S.; et al.
Journal:
SCIENCE OF THE TOTAL ENVIRONMENT
ISSN:
0048-9697
Year:
2023
Vol.:
879
pp.
162809
Authors:
Zamora-Marín J.M.; Ruíz-Navarro A.; Oficialdegui F.; et al.
Journal:
NEOBIOTA
ISSN:
1619-0033
Year:
2023
Vol.:
89
pp.
17 - 44
Aquatic ecosystems are particularly vulnerable to the introduction of non-indigenous species (NIS), lead-ing to multi-faceted ecological, economic and health impacts worldwide. The Iberian Peninsula comprises an exceptionally biodiverse Mediterranean region with a high number of threatened and endemic aquatic species, most of them strongly impacted by biological invasions. Following a structured approach that combines a systematic review of available information and expert opinion, we provide a comprehensive and updated multi-taxa inventory of aquatic NIS (fungi, macroalgae, vascular plants, invertebrates and vertebrates) in Iberian inland waters. Moreover, we assess overall patterns in the establishment status, in-troduction pathways, native range and temporal introduction trends of listed NIS. In addition, we discuss the legal coverage provided by both national (Spanish and Portuguese) and European NIS regulations. We inventoried 326 aquatic NIS in Iberian inland waters, including 215 established, 96 with uncertain estab-lishment status and 15 cryptogenic taxa. Invertebrates (54.6%) and vertebrates (24.5%) were the groups with the highest number of NIS, with Arthropoda, Mollusca, and Chordata being the most represented phyla. Recorded NIS originated from diverse geographic regions, with North and South America being the most frequent. Vertebrates and vascular plants were mostly introduced through intentional pathways (i.e. release and escape), whereas invertebrates and macroalgae arrived mostly through unintentional ways (i.e. contaminant or stowaway). Most of the recorded NIS were introduced in Iberian inland waters over the second half of the 20thcentury, with a high number of NIS introductions being reported in the 2000s. While only 8% of the recorded NIS appear in the European Union list of Invasive Alien Species of Union concern, around 25% are listed in the Spanish and Portuguese NIS regulations. This study provides the most updated checklist of Iberian aquatic NIS, meeting the requirements set by the EU regulation and providing a baseline for the evaluation of its application. We point out the need for coordinated transna-tional strategies to properly tackle aquatic invasions across borders of the EU members.
Journal:
LIMNETICA
ISSN:
0213-8409
Year:
2023
Vol.:
42
N°:
1
pp.
1 - 6
We reported the first record of the rare species Trocheta subviridis Dutrochet, 1817 (Arhynchobdellida, Erpobdellidae) from north-eastern Spain (Suspiro stream at Señorio de Bértiz Natural Park, Navarra, Spain). The species was previously recorded in Spain by Cordero del Campillo (1980) and García Más and Jiménez (1981). However, the latter authors admitted (Garcia Más & Jiménez, 1984) that both citations could be considered erroneous due to a misinterpretation by Cordero del Campillo of Blanchard (1893) (Jueg, 2008). Thus, considering the limited and uncertain information about T. subviridis in Spain, we can argue that our specimen is the first valid record reported for the species in the Iberian Peninsula.
Journal:
RESTORATION ECOLOGY
ISSN:
1061-2971
Year:
2023
Vol.:
31
N°:
8
pp.
1 - 10
The construction of riverine structures (weirs, bridges, or channelization) on riverbeds causes alterations in the flow regime and channel geometry. Once a new stretch is created, species must colonize it. The ecological succession processes that are entailed are decisive for adequate recovery after alterations, and understanding these processes would enable elaborate efficient restoration actions. We analyzed environmental variables and the colonization and succession patterns of fish assemblages in a new channelized stretch of a river from its construction to the present (from 1996 to 2020) in the northern Iberian Peninsula. During the studied period, habitat diversity increased, and mesohabitat became more complex. Depths, depth diversity, and the number of pools in the new channel increased with time. Water temperature decreased because of the new shade provided by riparian forests. The size-related variables of the fish community (size diversity, mean, and maximum length) increased in the new section, achieving similar values to those in the control section. The slopes of the fish size spectra showed a slow evolution over 25 years from a fish assemblage dominated by small fish to a more size-diversity fish community. Our results suggest that habitat complexity shape fish assemblage and structure. Moreover, size-related variables can be effective ecological indicators of fish colonization and succession processes. Finally, small-scale restoration measures in the riverbed and riparian forest are expected to increase the effectiveness of future restoration projects in rivers.
Journal:
AQUATIC CONSERVATION-MARINE AND FRESHWATER ECOSYSTEMS
ISSN:
1052-7613
Year:
2023
Vol.:
33
N°:
10
pp.
1028 - 1038
Freshwater habitats are vital for both humans and nature owing to their exceptional biodiversity and valuable ecosystem services, but they are currently facing serious threats. The designation and management of protected areas have been proposed as the most feasible way to ensure conservation objectives for the future. However, traditional approaches have not protected freshwater fauna effectively, especially freshwater fish.Previous studies have identified the most irreplaceable terrestrial places to achieve conservation goals. Here, the aim was to investigate how the present network of protected areas preserves irreplaceable rivers for freshwater fish.The irreplaceability of the world's river basins was calculated using International Union for the Conservation of Nature Red List distribution maps, considering the rarity, richness, and conservation status of their freshwater fish fauna. The overlap between irreplaceable basins and the present network of protected areas was also calculated.The results highlight the conservation significance of tropical rivers, particularly those in the Neotropics. The subset of the basins covering 30% of the most irreplaceable land surface (in line with the United Nations 30by30 target) encompasses 99% of freshwater fish species. However, protected areas do not seem to provide sufficient protection to these basins, as 89% of their surface area lies outside protected areas. Only 7% of freshwater ecoregions meet the United Nations 30by30 target.Given the context of climate change, allocating new protected areas becomes crucial in providing better survival opportunities for freshwater fish species. Despite the limitations inherent to the absence of total knowledge of freshwater fish biogeography and the irreplaceability index itself, this study identifies priority sites for their conservation that may help inform decision-making in the future to establish more effective protected areas.
Authors:
da Silva, J. P. (Autor de correspondencia); Sousa, R.; Vasconcelos Gonçalves, D.; et al.
Journal:
SCIENCE OF THE TOTAL ENVIRONMENT
ISSN:
0048-9697
Year:
2023
Vol.:
883
pp.
163689
Climate change is becoming the leading driver of biodiversity loss. The Mediterranean region, particularly southwest-ern Europe, is already confronting the consequences of ongoing global warming. Unprecedented biodiversity declines have been recorded, particularly within freshwater ecosystems. Freshwater mussels contribute to essential ecosystem services but are among the most threatened faunal groups on Earth. Their poor conservation status is related to the de-pendence on fish hosts to complete the life cycle, which also makes them particularly vulnerable to climate change. Species Distribution Models (SDMs) are commonly used to predict species distributions, but often disregard the poten-tial effect of biotic interactions. This study investigated the potential impact of future climate on the distribution of freshwater mussel species while considering their obligatory interaction with fish hosts. Specifically, ensemble models were used to forecast the current and future distribution of six mussel species in the Iberian Peninsula, including envi-ronmental conditions and the distribution of fish hosts as predictors. We found that climate change is expected to se-verely impact the future distribution of Iberian mussels. Species with narrow ranges, namely Margaritifera margaritifera and Unio tumidiformis, were predicted to have their suitable habitats nearly lost and could potentially be facing regional and global extinctions, respectively. Anodonta anatina, Potomida littoralis, and particularly Unio delphinus and Unio mancus, are expected to suffer distributional losses but may gain new suitable habitats. A shift in their distribution to new suitable areas is only possible if fish hosts are able to disperse while carrying larvae. We also found that includ-ing the distribution of fish hosts in the mussels' models avoided the underprediction of habitat loss under climate change. This study warns of the imminent loss of mussel species and populations and the urgent need of management actions to reverse current trends and mitigate irreversible damage to species and ecosystems in Mediterranean regions.
Journal:
ANNUAL REVIEW OF ANIMAL BIOSCIENCES
ISSN:
2165-8102
Year:
2023
Vol.:
11
pp.
287 -306
Zoos and aquariums have evolved significantly. From their origins as enclosures for the mere entertainment of the public, these institutions have undertaken new functions responding to the biodiversity crisis and social demands. Modern zoos and aquariums have the opportunity to educate people, contribute to species conservation, and produce animal-related research. However, there is increasing criticism toward the outcomes of their actions and the holding of species in their facilities. This review offers an integrated analysis of the state of knowledge about the role that zoos and aquariums play today. It describes their performance regarding their conservation, education, and research functions, highlighting general patterns and offering future perspectives. It identifies some challenges common to all these institutions, concluding that the way they keep up with the ever-growing social and environmental expectations will be decisive hereafter.
Journal:
NPJ BIODIVERSITY
ISSN:
2731-4243
Climate change is rearranging the mosaic of biodiversity worldwide. These broad-scale species re-distributions affect the structure
and composition of communities with a ripple effect on multiple biodiversity facets. Using European Odonata, we asked: i) how
climate change will redefine taxonomic, phylogenetic, and functional diversity at European scales; ii) which traits will mediate
species¿ response to global change; iii) whether this response will be phylogenetically conserved. Using stacked species distribution
models, we forecast widespread latitudinal and altitudinal rearrangements in Odonata community composition determining broad
turnovers in traits and evolutionary lineages. According to our phylogenetic regression models, only body size and flight period can
be partly correlated with observed range shifts. In considering all primary facets of biodiversity, our results support the design of
inclusive conservation strategies able to account for the diversity of species, the ecosystem services they provide, and the
phylogenetic heritage they carry in a target ecosystem.
Journal:
FISHES
ISSN:
2410-3888
Year:
2022
Vol.:
7
N°:
1
pp.
2
Biodiversity loss is a global problem, accelerated by human-induced pressures. In the marine realm, one of the major threats to species conservation, together with climate change, is overfishing. In this context, having information on the conservation status of target commercial marine fish species becomes crucial for assuring safe standards. We put together fisheries statistics from the FAO, the IUCN Red List, FishBase, and RAM Legacy databases to understand to what extent top commercial species¿ conservation status has been assessed. Levels of assessment for top-fished species were higher than those for general commercial or highly commercial species, but almost half of the species have outdated assessments. We found no relation between IUCN Red List traits and FishBase Vulnerability Index, depreciating the latter value as a guidance for extinction threat. The RAM database suggests good management of more-threatened species in recent decades, but more data are required to assess whether the trend has reverted in recent years. Outdated IUCN Red List assessments can benefit from reputed stock assessments for new reassessments. The future of IUCN Red List evaluations for commercial fish species relies on integrating new parameters from fisheries sources and improved collaboration with fisheries stakeholders and managers.
Journal:
HYDROBIOLOGIA
ISSN:
0018-8158
Year:
2022
Vol.:
849
N°:
6
pp.
1339 - 1349
IUCN Red List assessments for fish species can quickly become out of date. In recent years molecular techniques have added new ways of obtaining information about species distribution or populations. In this work, we propose the Iberian Peninsula as an example of reassessment needs in its endangered freshwater fish fauna. We compiled the list of freshwater fish species occurring in continental Spain and Portugal and examined their conservation status in global and national Red Lists. We retrieved records for these species in the Iberian Peninsula and calculated several biological indexes (richness and vulnerability indexes). Our results showed a patchy data coverage of fish records in the Iberian Peninsula. Threat levels reported within national Red Lists are higher than their global counterparts, reinforcing the necessity of improving and maintaining up to date national Red Lists. Iberian watersheds have moderate levels of threat and high levels of out of date assessments. The nearly fully completed genetic databases for Iberian fish species, along with the limited distribution of many endangered species and the necessity of update their assessments constitute an excellent opportunity to use data obtained from eDNA to improve species monitoring practices and their conservation status.
Journal:
HYDROBIOLOGIA
ISSN:
0018-8158
Year:
2022
Vol.:
849
pp.
4569 ¿ 4585
The lack of knowledge about freshwater biodiversity in remote areas like montane Andean rivers is noticeable and hinder the development of efficient conservation plans for aquatic ecosystems. Habitat requirements of tropical Andean fishes have been poorly analysed, despite the relevance of these ecological features on the fish conservation strategies. The present study aimed to examine fish assemblages along the altitudinal gradient in tropical Andean rivers and their relationship to habitat features to detect the most relevant abiotic factors and their implication on conservation. This study was conducted on a regional scale, along six basins located in tropical Andes (500 to 2,692 m a.s.l.). We studied fish diversity and distribution and their habitats along these elevation gradients. We found 6,320 specimens from 53 genera. Our analysis for the six most common and widely distributed genera (Astroblepus, Brycon, Bryconamericus, Chaetostoma, Pimelodella and Trichomycterus) underlines the relevance of hydromorphological variables on fish community structure in the Andean montane rivers, whereas human alterations seem to be less significant. These findings could be useful for current management and conservation strategies considering present threats over tropical montane rivers.
Journal:
REVIEWS IN FISH BIOLOGY AND FISHERIES
ISSN:
0960-3166
Year:
2022
Vol.:
32
N°:
3
pp.
975 - 991
Global biodiversitytargets require us to identify species at risk of extinction and quantify status and trends of biodiversity. The Red List Index (RLI) tracks trends in the conservation status of entire species groups over time by monitoring changes in categories assigned to species. Here, we calculate this index for the world's fishes in 2010, using a sampled approach to the RLI based on a randomly selected sample of 1,500 species, and also present RLI splits for freshwater and marine systems separately. We further compare specific traits of a worldwide fish list to our sample to assess its representativeness. Overall, 15.1% of species in the sample were estimated to be threatened with extinction, resulting in a sampled RLI of 0.914 for all species, 0.968 in marine and 0.862 in freshwater ecosystems. Our sample showed fishing as the principal threat for marine species, and pollution by agricultural and forestry effluents for freshwater fishes. The sampled list provides a robust representation for tracking trends in the conservation status of the world's fishes, including disaggregated sampled indices for marine and freshwater fish. Reassessment and backcasting of this index is urgent to check the achievement of the commitments proposed in global biodiversity targets.
Authors:
da Silva, J. P. (Autor de correspondencia); Goncalves, D. V.; Lopes-Lima, M.; et al.
Journal:
FRESHWATER BIOLOGY
ISSN:
0046-5070
Year:
2022
Vol.:
67
N°:
5
pp.
842 - 856
The freshwater pearl mussel Margaritifera margaritifera has been suffering major population declines in Europe. This endangered species is a host specialist and exclusively requires salmonid species (Salmo trutta and Salmo salar) to complete its life cycle. In theory, obligatory biotic interactions should deserve special conservation attention, because the loss or massive decline of fish hosts may elicit the extirpation of their affiliated species. While many threats disturbing M. margaritifera are similarly affecting salmonids, climate change is particularly alarming, with the potential to significantly change the fish-mussel dynamics. To evaluate the importance of including the occurrence of fish hosts for predicting the distribution of M. margaritifera in Europe, three datasets were used to build species distribution models (SDMs) with a maximum entropy (MaxEnt) approach: (1) environmental variables (ENV); (2) probability of fish hosts occurrence (FH); and (3) environmental variables and probability of fish hosts occurrence (ENV + FH). We identified the environmental variables that better explain M. margaritifera distribution and modelled its current and future distribution under a suite of climate change scenarios. Furthermore, projections were used to evaluate the adequacy of current networks of European protected areas in covering the suitable habitats for M. margaritifera.
Authors:
Laini, A.; Guareschi, S. (Autor de correspondencia); Bolpagni, R.; et al.
Journal:
PEERJ
ISSN:
2167-8359
Year:
2022
Vol.:
10
pp.
e14183
The monitoring of biological indicators is required to assess the impacts of environmental policies, compare ecosystems and guide management and conservation actions. However, the growing availability of ecological data has not been accompanied by concomitant processing tools able to facilitate data handling and analysis. Multiple common challenges limit the usefulness of biomonitoring information across ecosystems and biological groups. Biomonitoring data analysis is currently constrained by time-consuming steps for data preparation and a data processing environment with limited integration in terms of software, biological groups, and protocols. We introduce biomonitoR, a package for the R programming language that addresses technical challenges for the management of ecological data and metrics calculation. biomonitoR implements most of the biological indices currently used or proposed in different fields of ecology and water resource management. Its combination of customizable functions aims to support a transferable and comprehensive biomonitoring workflow in a user-friendly environment.
Journal:
ECOLOGICAL INDICATORS
ISSN:
1470-160X
Year:
2021
Vol.:
125
pp.
107557
Rivers are very vulnerable to fragmentation caused by the presence of man-made barriers. To restore river basin connectivity, numerous indices have been developed to calculate river fragmentation and optimise barrier mitigation actions. These methods usually calculate connectivity for whole river basins, but sometimes it is useful to analyse the connectivity for certain elements of interest. The main goal of this study was to develop a simple method to calculate the connectivity of specific riverine habitats or fish meta-populations. The framework of the Dendritic Connectivity Index (DCI) created by Cote et al. in 2009 was changed to develop the Population Connectivity Index (PCI). This index would depend on the number of populations, the total river length occupied by each population, the distance between populations, the dispersal capability of the fish species and the presence of barriers in the river. The outcome of the index is a percentage that measures the degree of connectivity in a meta-population. The PCI was tested in four Iberian fish species with different dispersal capabilities: Salmo trutta, Luciobarbus comizo, Anaecypris hispanica and Cobitis vettonica. The results show a natural connectivity between populations (without considering dams) of 7.95-47.48%. The most connected meta-population was L. comizo while the most naturally fragmented meta-population was A. hispanica. When large impassable dams were added to the index the results show a connectivity of 2.19-16.48%. Dams reduce connectivity between 5.37 and 30.99 points. Dams were ranked according to their impact in the fragmentation of each studied meta-population. This PCI allows to find out naturally isolated fish meta-populations and to assess the impact of dams in the fragmentation of fish meta-populations. It can also be used in dam prioritization decisions such as dam removals and new dam location selection. It also can aid in the creation of river ecological corridors between endangered or important fish populations.
Journal:
REVISTA DE LA ACADEMIA COLOMBIANA DE CIENCIAS EXACTAS, FÍSICAS Y NATURALES
ISSN:
2382-4980
Year:
2021
Vol.:
45
N°:
177
pp.
1097 - 1112
Hay pocos estudios ecológicos sobre los patrones de diversidad de los macroinvertebrados acuáticos en la Amazonía peruana, a pesar de ser esenciales para la gestión y manejo de estos ecosistemas fluviales. En este contexto, el objetivo del presente estudio fue determinar su composición taxonómica y su relación con las variables ambientales a lo largo de un gradiente altitudinal del río Alto Madre de Dios, cuenca en donde podrían registrarse nuevas especies. Se establecieron 22 estaciones en un rango altitudinal de 398 a 2.411 m s.n.m., cuantificando las características fisicoquímicas del agua y del hábitat fluvial: pH, temperatura del agua (T, °C), conductividad eléctrica (CE, ¿S.cm-1), ancho del río (A, m), profundidad (P, cm), sombra y velocidad del flujo de la corriente (m·s-1). Para los muestreos de macroinvertebrados se utilizó una red ¿de patada¿ de 200 ¿m de tamaño de malla. Se identificaron 56 taxones distribuidos en los órdenes Acari, Ephemeroptera, Coleoptera, Diptera, Hemiptera, Megaloptera, Odonata, Plecoptera, Trichoptera y Decapoda. Los análisis multivariados de clasificación y agrupamiento permitieron establecer cuatro grupos de estaciones estadísticamente diferenciadas (p<0,05), principalmente por la velocidad y el tipo de sustrato dominante, lo que explica la abundancia y amplia distribución de Chironomidae, Baetodes, Thraulodes y Anacroneuria.
Journal:
WATER
ISSN:
2073-4441
Year:
2021
Vol.:
13
N°:
14
pp.
1929
Authors:
Tobes, Ibon; Ramos-Merchante, A.; Araujo-Flores, J.; et al.
Journal:
WATER
ISSN:
2073-4441
Year:
2021
Vol.:
13
N°:
8
pp.
1038
Our study analyzes the distribution of fish communities related to the environmental variables of the Alto Madre de Dios River, an Andean-Amazon watershed of southern Peru, between 300 and 2811 m a.s.l. within the Manu Biosphere Reserve. We provide new ecological and diversity data on fishes for these poorly studied rivers and new data for palm swamp habitats. With electric fishing techniques, we collected a total of 1934 fish specimens belonging to 78 species, 42 genera and 15 families. To assess main patterns of diversity we combined SIMPER and ANOSIM with canonical correspondence analysis to obtain an overview of the community structure of fish and their distribution related to aquatic habitats. Our results show an important shift on fish diversity at 700 m a.s.l. separating headwater and middle-lowland communities. Electrofishing was a hindrance due to the depth, flow and low conductivity of the rivers, but also allowed us to capture fish not observed with other techniques. We also compared the use of elevation with slope as an alternative variable for statistical analysis. Our results show that slope offers a solid and equivalent explanation for fish distribution variability, avoids redundance, and instead of giving geographical data offers ecologically solid information.
Journal:
CONSERVATION BIOLOGY
ISSN:
0888-8892
Year:
2021
Vol.:
35
N°:
6
pp.
1894 - 1902
Zoos and aquaria, often regarded as preservation-cum-entertainment enterprises, are also actors in the effort to curb the biodiversity crisis: raising awareness, supporting conservation, and conducting research. We assessed trends in zoo and aquaria research topics and study organisms over time worldwide. For the zoos and aquaria registered in the Species360's Zoological Information Management System and the World Association of Zoos and Aquariums, we compiled metadata on their research published in the peer-reviewed literature indexed in Scopus and carried out a keyword frequency analysis. The production of scientific papers by zoos increased at a much faster rate than the average accrual of scientific papers in the literature. Evolution of research themes ran parallel to that of biological sciences (e.g., development of molecular genetics or increased awareness about conservation). The focus of 48.5% of zoo-led research was on vertebrates, of which mammal research was 33.7%. Whether zoos are effectively contributing to conservation may still be debatable, but our results highlight their institutional efforts to increase knowledge about the species in their care.
Journal:
ECOLOGICAL INDICATORS
ISSN:
1470-160X
Different indices have been developed to quantify the extent and severity of river fragmentation. These indices vary depending on the specific goals of the study. Here, we present a new Conservation Connectivity Index (CCIp) for potamodromous fish species that considers the conservation value (richness, rarity and vulnerability) of river segments.
The Iberian Peninsula holds > 20 endemic and endangered potamodromous fish species as well as > 1000 large dams (> 1 hm3 of capacity). The CCIp was calculated for the eight most important river basins of the Iberian Peninsula and compared to the Dendritic Connectivity Index (DCIp) developed by Cote et al. in 2009, which uses only river length as a habitat variable. With the use of both DCIp and CCIp, the dams were analysed and ranked according to their impacts on the river basin.
The main results show that Iberian river basins are heavily fragmented, with river basin connectivity percentages of less than 20% in most cases using both DCIp and CCIp. CCIp values are slightly higher than DCIP values in almost all cases. When the impact of individual dams is analysed, differences also appear between the DCIp and CCIp. CCIp highlights the impact of dams located in areas of high fish conservation value while DCIp emphasize the impact of dams fragmenting large river segments.
Journal:
AQUATIC CONSERVATION-MARINE AND FRESHWATER ECOSYSTEMS
ISSN:
1052-7613
Year:
2020
Vol.:
30
N°:
2
pp.
225 - 236
More than 33,500 fish species inhabit freshwater and marine environments, according to FishBase database records. The International Union for the Conservation of Nature (IUCN) has assessed the conservation status of approximately half of them, the lowest percentage in any vertebrate group.
In order to identify what factors may underlie this assessment gap, several traits were examined related to distribution, life-history, taxonomy, conservation, and the economic relevance of species according to their assessment status. IUCN assessment patterns were explored and separate analyses were included for freshwater and marine species.
The results showed that IUCN assessments were biased towards economically developed regions, species with early description dates and species covered by current IUCN specialist groups. Species living in remote areas or habitats were more likely to be unassessed. In particular, South America had low assessment levels. Other traits such as commercial importance did not influence the assessment status of fish species.
We therefore encourage assessment in poorly assessed areas and taxonomic subgroups to prompt timely conservation action to prevent species extinctions.
Authors:
Latorre, D.; Maso, G.; Hinckley, A.; et al.
Journal:
WATER
ISSN:
2073-4441
Year:
2020
Vol.:
12
N°:
8
pp.
2200
The bleak Alburnus alburnus is native to most of Europe. This cyprinid fish is a successful invader in the Iberian Peninsula. No studies exist on its foraging strategies on a large scale for this ecoregion. The aim of the present study was to compare dietary traits of invasive bleak among the main Iberian rivers and a "reference" native bleak population from France. Bleak were sampled during May-June 2019 from the Iberian Rivers Ebro, Tagus, Guadiana, Segura and Guadalquivir and the River Saône (France). Diptera larvae and zooplankton were common food categories in the River Saône. Insect nymphs were more important in the River Ebro. The intake of plant material was higher in the River Tagus. Flying insects were more consumed in the River Guadiana. Nektonic insects were important in the River Guadalquivir. Detritus was a frequent food category for all populations, in terms of occurrence and mass. Dietary parameters followed a unimodal response in relation to the latitudinal gradient, with the maximum values for the Tagus and Guadiana populations. Overall, results suggest that this wide interpopulation variability will contribute to the species¿ successful establishment throughout Mediterranean Europe, which poses a serious risk to its highly valuable native fish fauna.
Authors:
Gozlan, R. E.; Zahorska, E.; Cherif, E. ; et al.
Journal:
ECOLOGY AND EVOLUTION
ISSN:
2045-7758
Year:
2020
Vol.:
10
N°:
16
pp.
8623 - 8633
Rapid adaptation to global change can counter vulnerability of species to population declines and extinction. Theoretically, under such circumstances both genetic variation and phenotypic plasticity can maintain population fitness, but empirical support for this is currently limited. Here, we aim to characterize the role of environmental and genetic diversity, and their prior evolutionary history (via haplogroup profiles) in shaping patterns of life history traits during biological invasion. Data were derived from both genetic and life history traits including a morphological analysis of 29 native and invasive populations of topmouth gudgeonPseudorasbora parvacoupled with climatic variables from each location. General additive models were constructed to explain distribution of somatic growth rate (SGR) data across native and invasive ranges, with model selection performed using Akaike's information criteria. Genetic and environmental drivers that structured the life history of populations in their native range were less influential in their invasive populations. For some vertebrates at least, fitness-related trait shifts do not seem to be dependent on the level of genetic diversity or haplogroup makeup of the initial introduced propagule, nor of the availability of local environmental conditions being similar to those experienced in their native range. As long as local conditions are not beyond the species physiological threshold, its local establishment and invasive potential are likely to be determined by local drivers, such as density-dependent effects linked to resource availability or to local biotic resistance.
Journal:
WATER
ISSN:
2073-4441
Year:
2019
Vol.:
11
N°:
3
pp.
1 - 17
The signal crayfish Pacifastacus leniusculus Dana, 1852 is a successful invasive species in the Iberian Peninsula. This is of particular conservation concern, as fish fauna is highly endemic and also threatened within this ecoregion. The aim of this study was to analyze behavioral interactions and trophic overlap between signal crayfish and native fishes in Iberian rivers (northern Spain). Video cameras were used to record fish "dominance/evasion" after spatial encounters with crayfish. Diet composition and isotopic signatures (¿13C and ¿15N) were compared to evaluate the niche overlap. Fish were dominant in 25% of the encounters with juvenile crayfish, whereas this percentage was only 4% with adult crayfish. Observations showed a high fish "evasion" response for Pyrenean stone loach Barbatula quignardi (B¿cescu-Me¿ter, 1967) (>30%). Dietary results showed a high trophic overlap between signal crayfish with the pelagic Pyrenean minnow Phoxinus bigerri Kottelat, 2007 and the benthic loach. However, the isotopic niche overlap was low, with brown trout Salmo trutta L., 1758 showing the highest area (only 0.1 ¿2). Overall, our findings suggest that interferences may occur with native species for food (i.e., benthic invertebrates). Consequently, measures should be applied to control invasive crayfish in Iberian rivers.
Journal:
INLAND WATERS
ISSN:
2044-2041
Year:
2019
Vol.:
9
N°:
3
pp.
278 - 288
River fragmentation is one of the main threats to diadromous fish species. We aimed to create a new and simple connectivity index to calculate habitat accessibility that considers habitat suitability for fish species, using the Bidasoa River basin in the north of Spain and Atlantic salmon (Salmo salar) as an example. A habitat connectivity index (HCI) was calculated for the river basin using upstream passability and segment length as variables. We then calculated a new habitat quality index for each river segment and multiplied it by river segment length to create the Breeding Habitat Connectivity Index (HCIb). These 2 indices were first calculated using only upstream barrier passability and then by adding downstream passability. In each case, the indices show different outcomes but a similar pattern: in all cases, main-stem obstacles closest to the river mouth most affected the connectivity index, even when habitat quality was considered. Although we cannot compare the indices to the real area used by salmon because spatial tracking was not performed during the study years, we consider that including habitat quality in a river connectivity index adds useful information for scientists and managers.
Journal:
ORNIS FENNICA
ISSN:
0030-5685
Year:
2019
Vol.:
96
N°:
1
pp.
33 - 40
During the check-rearing period, strategies of prey provisioning can have a decisive impact on several reproductive aspects. Adults can maximise their foraging effort by increasing the number of fish-prey brought to the nest per unit time and/or by catching more energetic prey, i.e. larger prey or prey with relatively higher caloric values. The Common Kingfisher (Alcedo atthis) is a fish-eating predator normally breeding in freshwater habitats. We collect data on fish-prey proportions found at nests (n=10) and determined the caloric content of such fish-prey (6 species overall) in rivers in northen Iberia. The proportion of each fish-prey species in the nest was not correlated with the proportion of lipids, proteins or carbihydrates, nor with its caloric content. Furthermore, the most energetic prey was nor the most coomonly consumed, illustrating the fact that the Common Kingfisher does not fish for the most energetic prey during the chick-rearing period.
Journal:
INLAND WATERS
ISSN:
2044-2041
Year:
2019
Vol.:
9
N°:
3
pp.
275 - 277
Assessment of freshwater ecosystems is crucial for measuring their ecological status and providing primary information for their conservation. This editorial introduces a special section of Inland Waters regarding the study of ecological monitoring and biodiversity conservation of inland waters. Papers in this special section of Inland Waters are briefly described and a synthesis of the topic is provided to offer a summary of contents and an overview of the subject matter.
Journal:
FRONTIERS OF ARCHITECTURAL RESEARCH
ISSN:
2095-2635
Year:
2019
Vol.:
8
N°:
1
pp.
17 - 31
The strategies for thermal regulation and environmental control found in nature are countless. In this article, a parallelism between animals and building energy systems is defined in order to identify and emphasize the immediate opportunities that biomimicry offers for future research. The motivation was the need to find alternative solutions to tackle problems mainly in the efficiency of heating, ventilation and cooling systems. Due to the wide range of possibilities offered by animals, this study is largely limited to the strategies that cold-blooded animals have developed through evolutionary adaptation to the environment.
The method used for the analysis is based on a solution-based approach. Firstly, different animal thermoregulation strategies are defined (biological domain). Then the strategy is analyzed and classified into three categories. This classification is essential in order to formulate the parallelism with building systems (transfer phase). The final step is to identify the potential implementation (technological domain).
This approach has been seen to be useful in creating new research opportunities based on biomimicry. In addition, suitable solutions arising from multidisciplinary team research are presented as promising answers to the challenges that building energy systems face nowadays.
Authors:
Latorre, D. ; Maso, G.; Hinckley, A.; et al.
Journal:
MARINE AND FRESHWATER RESEARCH
ISSN:
1323-1650
Year:
2018
Vol.:
69
N°:
8
pp.
1326 - 1332
The native European freshwater cyprinid fish, common bleak Alburnus alburnus (Linnaeus, 1758), is an invasive non-native fish in the Iberian Peninsula, where it threatens the valuable endemic fish fauna. Despite the bleak's invasive status, there is a dearth of studies on the biological traits of non-native populations in Europe's Mediterranean region, and the present study aimed to compare bleak growth and reproductive traits across the principal rivers of Iberia with those from a native 'reference' bleak population in France. Non-native bleak from the River Tagus had the highest back-calculated total lengths (TLs), growth rate and body condition, but the lowest reproductive investment and smallest egg size of all studied populations. Whereas, these latter two traits were the highest in the River Ebro, where fecundity was the lowest for all Iberian rivers. The youngest age and the smallest TL at maturity were observed in the River Ebro. The River Segura had the lowest back-calculated TLs and growth rate, the highest fecundity and proportion of females, and the oldest age at maturity. Population traits of bleak in the River Saone (the native 'reference' population) were generally different from those in Iberian rivers, except for the River Ebro. This wide inter-population variability contributes to the species' successful establishment in novel habitats.
Journal:
ECOSCIENCE
ISSN:
1195-6860
Year:
2018
Vol.:
25
N°:
1
pp.
85 - 95
Knowledge of the fish assemblages of Andean mountain streams is restricted to accessible areas. This study is the first biological survey of the remote Suaza River in the Colombian Andes, at its source in the Cueva de los Guacharos National Park. Mechanistic insight into the ecological patterns and gradients of the river is provided, focusing on the spatial distribution of fish communities in relation to environmental variables and habitat characteristics. Electrofishing surveys and macroinvertebrate sampling were carried out, the river habitat was characterized, three environmental quality indices were applied, and potential water pollutant concentrations were measured. Twenty-seven fish species were recorded - two of them exotic (Poecilia reticulata and Xiphophorus hellerii) - as well as 45 macroinvertebrate families. Fish species richness was higher at lower altitudes with gentle slopes, where habitat temperature, size and heterogeneity were higher. Although macroinvertebrate diversity slightly increased downstream following a similar pattern as fish species richness, it declined at lower sites. Fish assemblages were distributed in three clusters corresponding to headwaters, middle sections and lower reaches of the river, showing correlations with environmental factors, suggesting habitat preferences. Although the headwaters of the Suaza River remains pristine inside the park, human influence is responsible for ecosystem alteration downstream.
Authors:
Benejam, L. (Autor de correspondencia); Tobes, Ibon; Brucet, S.; et al.
Journal:
ECOLOGICAL INDICATORS
ISSN:
1470-160X
Year:
2018
Vol.:
90
pp.
366 - 378
The estimation of biodiversity is complex in remote areas like Andean-Amazon piedmont where the lack of knowledge is noticeable and most species have not yet been identified. An alternative to the taxonomical approach to assess biodiversity and community structure is to study the body size structure of the community. The present study aimed to identify systematic changes of the size structure of fish communities along the altitudinalgradient of pristine Andean streams. At the same time, we assessed if size structure of fish communities could be an alternative or complementary approach to traditional taxonomic metrics of ecological assessment. This study was conducted along two rivers of eastern Andean piedmont: Hacha River and Alto Madre de Dios basin. Our analysis showed lower values of total size range, maximum length and number of size classes in the highest places and increasing in lower reaches of the rivers. Concerning abundance size spectra, we found flatter slopes
(indicating higher relative abundance of large fish) and lower coefficient of determination (i.e. less linear size spectra) and intercept at y-axis on upstream reaches. On the other hand, fish abundance, species richness and species diversity increasing from upstream to downstream. These systematic changes on size-related variables were similar using both basins together or independently and may be used in future studies as management reference conditions when assessing the effect of perturbations ...
Journal:
MARINE AND FRESHWATER RESEARCH
ISSN:
1323-1650
Year:
2017
Vol.:
68
N°:
5
pp.
900 - 908
The identification of habitat requirements of invasive species is essential to evaluate their spread and to assess the vulnerability of recipient ecosystems. We studied the distribution and abundance of the invasive signal crayfish (Pacifastacus leniusculus) in 43 sites in northern Spain and analysed the relationships with several abiotic and biotic parameters of the aquatic ecosystems. Our results indicated that the abundance of signal crayfish was positively associated with vegetation cover and negatively associated with boulders. Also, its abundance was positively correlated with water temperature, organic matter, cations (e.g. sodium), anions (e.g. sulfates) and abundance of some native fish species (Parachondrostoma miegii and Luciobarbus graellsii). We concluded that the habitat of signal crayfish is among salmonid stretches (headwaters) with cold waters and low proportion of organic debris, and among cyprinid stretches (low waters) with warmer waters which it inhabits with another invasive crayfish, the red swamp crayfish (Procambarus clarkii). Our analysis indicated that the presence of signal crayfish is limited in the uppermost stretches by lower water temperatures and a lower proportion of organic debris. The existence of a natural environmental limiting factor in upstream reaches facilitates the conservation of aquatic ecosystems and native fauna.
Journal:
ENERGY AND BUILDINGS
ISSN:
0378-7788
Year:
2017
Vol.:
134
pp.
25 - 36
Finding new solutions for energy recovery in buildings is crucial to diminish the energy consumption. Some proposals may unveil innovative products to solve this challenge. However, reinventing and reformulating the configuration of available solutions might be another way to find an inventive answer to the energetic problem. The main aim of this article is to check if several cores connected in a cascade layout and installed in two different rooms can provide a better performance making use of energy from exhaust air. This study was inspired by the rete mirabile of tuna. This strategy proposed by nature has been translated into building services. Thanks to this reinterpretation, a new configuration of heat recovery ventilators (HRVs) has been simulated with CFD software. The results obtained show that up to 44.5% of energy could be saved with the new configuration making it a promising solution and a foreseeable application for energy recovery in buildings.
Journal:
AQUATIC CONSERVATION-MARINE AND FRESHWATER ECOSYSTEMS
ISSN:
1052-7613
Year:
2017
Vol.:
27
N°:
4
pp.
880 - 885
1. Many human activities in and on rivers cause the loss of freshwater biodiversity, especially fish, which now are one of the most endangered vertebrate groups. River fragmentation caused by the construction of dams is one of the main threats to fish species. In Spain, which has the highest number of dams per square kilometre in the world, more than half of all fish species are threatened by these constructions. The government has initiated the National Strategy for River Restoration, a plan to restore rivers and preserve their inhabitants, which includes the removal of dams. 2. An information search and query was conducted to determine if fish monitoring was performed before and after dam removal, and the result was negative. Therefore, an assessment of the effects of dam removal on fish communities at a large spatial scale was not possible. Instead, an analysis was carried out to measure the effects of dam removal on river connectivity using a geometric network. 3. The analysis of river connectivity improvement showed that 66% of removed dams had one or more dams less than 5km away. The removal of dams increased the connected river length by an average of 6.4km per dam removed, with the range varying between 1.04km and 9.48km, depending on the river basin. 4. These results show that, although monitoring programmes are strongly recommended after restoration actions, they are not usually performed. This is a wasted opportunity to gather large datasets to understand better the effects of human actions on fish communities and on rivers. 5. River connectivity results may reflect a demolition strategy based more on economic and social opportunism rather than on ecological considerations. It is strongly recommended that dam removal plans should be based on ecological selection methods to achieve greater river improvements with less investment.
Journal:
AQUATIC CONSERVATION-MARINE AND FRESHWATER ECOSYSTEMS
ISSN:
1052-7613
Year:
2017
Vol.:
27
N°:
4
pp.
898 - 899
Journal:
JOURNAL OF APPLIED ICHTHYOLOGY
ISSN:
0175-8659
Year:
2016
Vol.:
32
N°:
1
pp.
240 - 248
The number of threatened freshwater fish species in Spain is among the highest recorded in Europe and includes a high percentage of endemic taxa. Investigated were the distribution of Spanish freshwater fish to identify priority areas for conservation and assess the extent to which freshwater fish are included in the existing network of protected areas. Considered were those threatened species recorded in the Spanish National inventories. From these data, several biodiversity indices were calculated and analysed. The results reveal important discrepancies between the national and international assessments of conservation status, whereby the current Spanish national catalogue needs updating to reconcile these inconsistencies. Several important areas for the conservation of freshwater fish lie outside protected areas. The results encourage the establishment of protected areas specifically for freshwater environments. An extensive database of Spanish freshwater fish species is needed to redefine priority areas and to maintain freshwater biodiversity.
Journal:
JOURNAL OF APPLIED ICHTHYOLOGY
ISSN:
0175-8659
Year:
2016
Vol.:
32
N°:
1
pp.
229 - 239
This work studied the ecological integrity of river ecosystems inside the Ordesa-Viñamala Biosphere Reserve in the central Spanish Pyrenees. Despite its protected status, the reserve endures a considerable number of human stresses, thus the aim was to evaluate the conservation status of the two river basins inside the protected area: The Gállego River Basin, inside the transition zone of the protected area and which allows a wide range of human activities; and the Ara River Basin, inside the buffer zone where only sound ecological practices are authorised. The environmental status of river ecosystems was analysed by studying fish and macroinvertebrate communities, hydrochemical and habitat characteristics and by calculating environmental quality indices. From August to September 2011, a total of 14 sites were sampled. Fish sampling was conducted using electrofishing gear, and macroinvertebrate were sampled by applying the IBMWP and IASPT procedures. Results showed that, while the Ara River Basin maintains a solid ecological integrity, the Gállego River Basin endures important habitat alteration. Trout, the dominant and exclusive species in the Ara River, were absent and replaced by translocated native cyprinids in the Gállego River Basin. This colonisation was explained by the alteration of the stream ecosystems and their homogenisation. The study of macroinvertebrate communities and the diagnosis obtained with the environmental quality indices also enhanced the deficient ecological integrity of some sites in the Gállego River. The results suggest that the Biosphere Reserve is not providing adequate protection to streams inside its boundaries, leading to major degradation of their biological integrity.
Journal:
SCIENTIFIC DATA
ISSN:
2052-4463
Year:
2016
Vol.:
3
pp.
UNSP 160091
The study of freshwater fish species biodiversity and community composition is essential for understanding river systems, the effects of human activities on rivers, and the changes these animals face. Conducting this type of research requires quantitative information on fish abundance, ideally with long-term series and fish body measurements. This Data Descriptor presents a collection of 12 datasets containing a total of 146,342 occurrence records of 41 freshwater fish species sampled in 233 localities of various Iberian river basins. The datasets also contain 148,749 measurement records (length and weight) for these fish. Data were collected in different sampling campaigns (from 1992 to 2015). Eleven datasets represent large projects conducted over several years, and another combines small sampling campaigns. The Iberian Peninsula contains high fish biodiversity, with numerous endemic species threatened by various menaces, such as water extraction and invasive species. These data may support the development of large biodiversity conservation studies.
Journal:
DYNA (ESPAÑA)
ISSN:
0012-7361
Year:
2016
Vol.:
91
N°:
5
pp.
507 - 511
The article proposes new ways of work to redesign previous Peltier cells prototypes using biomimetic methodologies. Biomimicry can be a source of fresh ideas to solve contemporary problems. Also in terms of energy saving and efficiency, animals can be of aid. Ectotherms, animals that depend on external factors to be in a range of `living temperature¿, have developed strategies to survive and adjust their metabolism regarding the environment and weather conditions.
Social insects are ectotherm animals. One specimen of these species cannot be autonomous and would die if he is out of his nest for a long or even short time. Previous studies made about bees behaviour in beehives show up an automated and accurate work to maintain nest temperature.
Strategies such as the heat shield or stigmergy have been translated to obtain better control of the air cavity and a decentralized computational control of the equipment.
Journal:
INLAND WATERS
ISSN:
2044-2041
Year:
2016
Vol.:
6
N°:
1
pp.
54 - 64
Environmental conditions and host features that influence the abundance of an exotic branchiobdellidan were studied. One of the most widespread invasive crayfish species in Europe is the signal crayfish, Pacifastacus leniusculus (Dana, 1825). Along with this invasive crayfish, other alien species that live on the crayfish¿s body surface, such as bacteria, algae, fungi and invertebrates, were introduced. One of these symbiont species is a branchiobdellidan worm, Xironogiton victoriensis (Gelder and Hall, 1990). Because a previous study identified this exotic branchiobdellidan in 3 different and spatially separate populations of the red swamp crayfish, Procambarus clarkii (Girard, 1852), an investigation into the factors affecting its abundance was necessary. We sampled 1817 sites between 2005 and 2013 in the Ebro Basin (Spain), and the distributions of X. victoriensis and P. leniusculus were represented and interpreted. Furthermore, we sampled 2914 crayfish from 43 Spanish localities to investigate the influence of environmental conditions and host features (sex, body size, body condition, density and ecdysis) on the abundance of X. victoriensis. The abundance of the branchiobdellidan was higher in the largest individuals and in those showing the best body condition. The crayfish body condition (or welfare) increased significantly with the branchiobdellidan infestation, suggesting that mutualism is the biological relationship between X. victoriensis and P. leniusculus. Although 91.04% of the adult signal crayfish were infested with X. victoriensis, only 59.3% of the juveniles were infested. Nonmolted crayfish had higher branchiobdellidan abundance than that of recently molted host specimens; however, the abundance of the symbiont did not differ between sexes and host densities. Finally, biochemical oxygen demand, phosphates, coliforms, and potassium were positively related with the branchiobdellidan abundance. The relationships between some environmental variables and the abundance of branchiobdellidans have not been previously well studied, and these findings will be important for risk assessments and models predicting the spread of exotic branchiobdellidans.
Journal:
JOURNAL OF APPLIED ICHTHYOLOGY
ISSN:
0175-8659
Year:
2016
Vol.:
32
N°:
6
pp.
1256 - 1258
The present work provides the estimates of morphometric relationships for 22 native freshwater fish species (11 Characidae, five Loricariidae, two Heptapteridae, one Astroblepidae, one Crenuchidae, one Curimatidae and one Erythrinidae) collected in the Alto Madre de Dios River (Cuzco and Madre de Dios, Peru) in June 2012 using a mobile backpack electrofishing unit. These are the first length¿weight relationships reported for 24 species, mostly endemic to the Amazonian basin. Knowledge regarding these biometric relationships can be relevant in the management and conservation of the local fishes and fisheries.
Journal:
ACTA ICHTHYOLOGICA ET PISCATORIA
ISSN:
0137-1592
Year:
2016
Vol.:
46
N°:
2
pp.
137 - 140
The knowledge of freshwater fishes in remote Andean mountains is scarce and restricted to changes of occurrence distribution along a specific gradient. The high number of endemic fish species requires further studies regarding their biology and their conservation status. The present study aims to estimate the length-weight, length-length, and length-girth relations for nine native freshwater fish species representing five families (Loricariidae, Characidae, Heptapteridae, Crenuchidae, and Parodontidae): Chaetostoma thomsoni Regan, 1904; Lasiancistrus caucanus Eigenmann, 1912; Rineloricaria jubata (Boulenger, 1902); Bryconamericus huilae Roman-Valencia, 2003; Gephyrocharax melanocheir Eigenmann, 1912; Pimelodella chagresi (Steindachner, 1876); Rhamdia guatemalensis (Quoy et Gaimard, 1824); Characidium fasciatum Reinhardt, 1867; Parodon suborbitalis Valenciennes, 1850. The fishes were collected in the Suaza River (Huila, Colombia). These are the first length-weight relations reported for all these species, mostly endemic to the Colombian Andes. The report also provides the new maximum size for four species.
Journal:
INLAND WATERS
ISSN:
2044-2041
Year:
2016
Vol.:
6
N°:
1
pp.
89 - 104
This work provides insight into an Andean¿Amazonian river system by conducting a comprehensive study of the biodiversity and ecological processes in a poorly studied neotropical freshwater ecosystem. Hacha River in western Colombia harbours a rich and largely unknown biodiversity and is experiencing an increase in anthropogenic impacts from the city of Florencia. Changes in natural habitat characteristics and environmental quality were analysed and related to the distribution of fish and macroinvertebrates. Four environmental quality indices were applied, and concentrations of potential water pollutants were measured. All environmental quality indices used were reliable because they produced similar assessments of the ecological integrity of the study sites and were inversely related to the potential water pollutant concentrations. Fish and macroinvertebrate communities notably changed in response to differences in environmental quality, reinforcing the ecological integrity assessments. Nevertheless, natural gradients that influence fish and macroinvertebrate distributions showed an overlap with changes in environmental quality, thereby confounding the ability to discern the influence of natural and anthropogenic-induced alterations and to confirm an initial shift in fish assemblages due to anthropogenic impacts.
Journal:
BUILDING SIMULATION
ISSN:
1996-3599
Year:
2016
Vol.:
9
N°:
3
pp.
343 - 357
This paper is comprehended in the study of the application of the biomimicry science in building services and energy management, taking as a reference the case of tuna. Tuna generates heat in the muscles, organs and tissues of the inner area of its body (dark muscles). This heat is distributed in the periphery in order to maintain constant body temperature. From this biological reality, researchers analyse the possibility of altering the heating demand of an office on the basis of the heat conservation strategy applied by tuna, merely modifying the working-spaces. For this purpose, an existing office building with high architectonical quality parameters has been chosen and different scenarios have been defined in order to perform the energy simulations. The case studies correspond to the variations in the floor layout and occupancy density distribution. Besides, they are studied in three European cities with different climate. The evaluation of results is mainly focused on the heating demand since tuna strategy comprises the heat management. It is shown that the arrangement of high thermal load locals affects the heating demand of the building, being more efficient the tuna distribution in order to lower the demand.
Authors:
Bautista-Hernández, C. E.; S.; G.; et al.
Journal:
ZOOKEYS
ISSN:
1313-2989
Year:
2015
Vol.:
482
pp.
55 - 66
Paracreptotrema rosenthali sp. n. was discovered in the intestine of Xiphophorus malinche and Pseudoxiphophorus jonesii, collected from the headwaters of Rio Malila, tributary of Rio Conzintla, in the Rio Panuco basin, Hidalgo, Mexico, during 2008-2009. The new species differs from the five known species of Paracreptotrema Choudhury, Perez-Ponce de Leon, Brooks & Daverdin, 2006 by having vitelline follicles that extend from a level anterior to the pharynx to mid-testes, the seminal vesicle which is more extensively folded, and a wider cirrus sac. The new species resembles P. heterandriae in the length of its ceca, which surpasses the posterior margin of the ovary but do not reach the testes. A key to the species of Paracreptotrema is provided.
Journal:
INLAND WATERS
ISSN:
2044-2041
Year:
2015
Vol.:
5
N°:
1
pp.
89 - 92
Invasive alien species present a global threat to biodiversity, particularly where pathogens and symbionts are involved. Branchiobdellidans are clitellate annelids with an obligate ectosymbiotic association primarily on astacoidean crayfish. There are several examples of branchiobdellidan species adopting a geographically exotic host where endemic and exotic crayfishes cohabit the same water body. The first records of a western North American branchiobdellidan, Xironogiton victoriensis, adopting the eastern North American crayfish, Procambarus clarkii, in 2 river basins in Spain provide further evidence of the ectosymbionts¿ tolerance to adopt an exotic host. Given worldwide translocations of these and other commercial crayfish species, limnologists and agency managers need to be alert for further introductions of X. victoriensis and other branchiobdellidans. Impacts of these exotic ectosymbionts on habitat and biota at a new location are unknown, as are their consequences on native biodiversity.
Journal:
TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY
ISSN:
0002-8487
Year:
2015
Vol.:
144
N°:
2
pp.
431 - 442
The Owens Tui Chub Siphateles bicolor snyderi has become endangered by introgressive hybridization with the Lahontan Tui Chub S. bicolor obesa since the 1960s. Adequate conservation strategies require prior identification of pure populations, which is usually difficult because the diagnostic features presented in the formal subspecies description do not always allow unequivocal determination of populations. In the present study, the shape and some meristic features of the scales, along with the shape of other bones with taxonomic value, were analyzed to distinguish both parental subspecies and their hybrids in samples diagnosed in a previous work using microsatellite DNA. Scales, pharyngeal arches, dentaries, cleithra, and opercula of 211 individuals from 16 localities across the Owens River and neighbouring basins in California and Nevada were compared. The results show that the meristic parameters of the scales were in agreement with values provided by Miller (1973) for the parental subspecies. Shape analyses were based on landmark or Fourier methods, depending on the shape characteristic of each structure. Geometric morphometric analyses provided variable discriminatory power between subspecies depending on the studied bone. In scales, pharyngeal arches, and dentaries, the derived morphological patterns matched the shape descriptions set forth by Miller (1973) for both parental subspecies. In all cases, the observed morphometric variability of hybrids was too high to separate them from parental subspecies. However, joint analysis of the five structures produced groupings that were concordant with the genetic analyses: localities of parental subspecies in separate groups and an intermediate group with the hybrid swarm localities that was morphologically closer to Lahontan. Finally, a new derived parameter (the ratio between scale lengths from the anterior and posterior body) is suggested as a promising tool for rapid discrimination of Owens Tui Chub from Lahontan Tui Chub and their hybrid populations.
Journal:
CONSERVATION BIOLOGY
ISSN:
0888-8892
Year:
2015
Vol.:
29
N°:
2
pp.
599 - 601
Journal:
BIODIVERSITY AND CONSERVATION
ISSN:
0960-3115
Year:
2014
Vol.:
23
N°:
9
pp.
2239 - 2258
The knowledge of species occurrence within an area is crucial to develop proper conservation strategies to protect species diversity. Biosphere Reserves (BRs), established to preserve biodiversity and sustainably use their resources, should therefore have precise information of its biodiversity. We compared and evaluated information on threatened and non-threatened vertebrate species available for Spanish BRs from three sources: management documents (MDs), the Global Biodiversity Information Facility index (GBIF), and atlases and red books. Our results suggest that information from any one source was rather partial, to a degree that depended on which vertebrate group was considered. Management documents did list a high percentage of threatened species found in BRs, reaching up to the total number of species of birds and mammals. Species lists overlap between all three sources ranged from 59 % for fish to 84 % for mammals. In addition, there is an inconsistency between national and international threatened species categories and it should thus call for revisions. Even though the information of non-threatened and threatened species occurrence in MDs of Spanish BRs is good, it is necessary to pay attention to amphibian and fish species which are less recorded.
Journal:
ZOOKEYS
ISSN:
1313-2989
Year:
2014
N°:
403
pp.
67 - 109
The state of Hidalgo (Mexico) is an important region from the point of view of biodiversity. However, there exists a significant gap in accessible knowledge about species diversity and distribution, especially regarding to freshwater ecosystems. This dataset comprises the sampling records of two projects developed in Hidalgo between 2007 and 2009 about the freshwater fish communities of Tecocomulco lake and rivers belonging to the Metztitlan Canyon Biosphere Reserve. It contains the taxonomic identity (species level) and basic biometric data (total length and weight) as well as date of collection and coordinates of more than 9000 specimens. This dataset is the primary result of the first and unrepeated exhaustive freshwater fish's survey of Metztitlan Canyon Biosphere Reserve and Tecocomulco lake. It incorporates seven more species to the regional fish fauna, and new exclusive biometric data of ten species. This dataset can be used by studies dealing with, among other interests, North American freshwater fish diversity (species richness, distribution patterns) and biometric analyses, useful for the management and conservation of these areas. The complete dataset is also provided in Darwin Core Archive format.
Journal:
ENVIRONMENTAL BIOLOGY OF FISHES
ISSN:
0378-1909
Year:
2014
Vol.:
97
N°:
2
pp.
157 - 161
Biosphere reserves have been established around the world as a means to protect sensitive or threatened ecoregions and the biodiversity within them. As such, the organisms occurring within these reserves are important from a conservation perspective as they often represent endemic species or remnant populations. Here we provide genetic evidence of widespread occurrence of Xiphophorus helleri within the Metztitlan Canyon Biosphere Reserve in Hidalgo, Mexico. One nuclear and two mitochondrial genes were sequenced from four populations within the canyon and confirmed that the specimens collected were X. hellerii. When compared to published sequences of X. hellerii from multiple localities within the documented natural range of the species, the specimens from Metztitlan were found to exhibit between 0 and 1.6 % sequence divergence. Possible scenarios for colonization of the canyon and conservation implications are discussed.
Journal:
BIOLOGICAL CONSERVATION
ISSN:
0006-3207
Year:
2014
Vol.:
173
pp.
74 - 79
The knowledge of biodiversity within an area is vital if we want to develop adequate conservation strategies. Biosphere Reserves are purposefully established for the sustainable use of their resources, and therefore their biodiversity should be well known. We compared and evaluated information available for Mexican Biosphere Reserves on threatened and non-threatened vertebrate species records from three different sources ¿ the corresponding Biosphere Reserves management plans (MPs), the Global Biodiversity Information Facility index (GBIF), and scientific literature, in order to find potential knowledge gaps. Our results suggest that there were varying gaps in information among sources according to vertebrate group. For each group of vertebrate species, management plans held the largest subsets of information but were not complete, ranging from 89.6% of the combined known species of birds to 70% for amphibians and freshwater fishes. However, both GBIF and literature included data absent from MPs, and GBIF included data not otherwise available, proving it as important as literature or other data sources (e.g. field data) used for crafting such plans. Moreover, we found references to threatened species that were not listed in the MPs, reaching to as many as 50% of the total known species of fish. Species information shared by all three sources ranged from 28% for amphibians to 72.5% for birds. Conservation efforts should therefore take into account that possibly less charismatic taxa such as amphibians, reptiles and freshwater fish lack more information than birds or mammals. The disparity observed in the vertebrate species information constitutes an information gap that could (or should) be solved by scientists and managers alike.
Journal:
BEHAVIOURAL PROCESSES
ISSN:
0376-6357
Year:
2013
Vol.:
98
pp.
25 - 30
To investigate how depth and bottom color affect prey selectivity in Common kingfisher (Alcedo atthis), we developed several experimental procedures using captive birds. We used 20 young kingfishers to test depth (25 or 50 cm) and color (natural gravel or white) effects on foraging behavior. Live freshwater fish were used as target prey. To assess differences resulting from the natural behavior of different fish, we chose bottom-dwelling [Ebro barbel (Barbus graellsii)] and open-water benthopelagic species [Ebro nase (Parachondrostoma miegii) and Pyrenean minnow (Phoxinus bigerri)]. The number of attempts and captures, as well as the effects of hunger and experience, were assessed relative to feeding behavior. The effect of fish behavior, as observed in grouped vs. isolated fish, on the kingfisher's performance was also tested. The results showed a significant effect of depth, with more attacks and greater success in shallow waters. No significant differences in catch success between natural- and white-colored bottoms were observed. Hunger had no effect on fishing success, but experience had a positive effect in shallow waters and on white bottoms. Both bottom- and open-water species were consumed equally. Kingfishers preyed more often upon grouped prey than upon isolated prey, although capture success did not vary between the two cases. Our results suggest that kingfishers prey upon the most accessible types of prey.
Journal:
JOURNAL OF FISH AND WILDLIFE MANAGEMENT
ISSN:
1944-687X
Year:
2013
Vol.:
4
N°:
2
pp.
326 - 331
Regression parameters for the length of several bony structures against fish body length, and for body length against body weight, were determined for Owens tui chub Siphateles bicolor snyderi, Lahontan tui chub Siphateles bicolor obesa, and hybrid swarm deriving from the two species. Two-hundred eleven individuals from 16 localities from the Owens River and neighboring basins along the border between California and Nevada were used for regression analyses. The coefficient of determination of linear regressions for scales, pharyngeal arches, dentaries, cleithra, and opercula against body length were consistently high (r(2) >= 0.9). Differences between subspecies were mainly with reference to the intercept parameter in comparisons involving Lahontan tui chub. Coefficients of determination from log-linear length-weight regressions were also high (r(2) >= 0.9) for individual taxa and for the pooled data set combining both Lahontan and hybrid species. The length-weight relationship did not differ between subspecies. Estimates of the length-weight relationship using data pooling both Lahontan and hybrid tui chub suggest a weak allometric growth effect (P < 0.05). The bone-length to body-length and body-length to body-weight relationships presented here will be useful tools for future dietary studies of tui chub predators as well as for archaeological and paleontological studies on tui chub remains.
Journal:
KNOWLEDGE AND MANAGEMENT OF AQUATIC ECOSYSTEMS
ISSN:
1961-9502
Year:
2013
Vol.:
410
pp.
03
The effect of fish-eating birds on their fish-prey populations has been a matter of concern to conservationists, anglers and fishery interests, especially when both bird and fish species have conservation status and are afforded some protection by law. Understanding the predator-prey interactions will assist in managing these potential conflicts. This situation could arise with the Common Kingfisher (Alcedo atthis), whose range covers many important Atlantic salmon (Salmo salar) rivers. In order to increase our knowledge on predator-prey interactions between these species, we collected data on the diet and feeding rates of a kingfisher population breeding in an Atlantic salmon river in southern England (River Frome). Results showed that, during nestling period, kingfishers provided a mean of 62 fish per day to the nest and that the mean salmon intake was 2.5% of the entire diet, which is equivalent to 86 salmon parr consumed by each kingfishers pair for the entire breeding period (assuming 2.2 broods/pair/year). The total 0-group salmon population in the River Frome was 63 900. The estimated loss of 0-group salmon parr to the kingfishers over one season was 0.8%, thus supporting the view that the kingfisher has a negligible biological impact over this salmon population.
Journal:
MOLECULAR PHYLOGENETICS AND EVOLUTION
ISSN:
1055-7903
Year:
2013
Vol.:
66
N°:
1
pp.
80 - 90
Phylogenetic relationships of species of genus Pseudoxiphophorus have been only tackled in detail based on morphology so far. However, phylogenetic evidence based on molecular data is still lacking. In this study, we have used five molecular markers (mitochondrial cytb, 16S, atp6-8, and nuclear actB and S7) to reconstruct a robust, inclusive phylogeny of Pseudoxiphophorus. Our phylogenetic results strongly disagree with the main morphological hypothesis, and indicate different phylogenetic relationships among the recognized species of Pseudoxiphophorus. Pseudoxiphophorus jonesii is recovered as the sister group of all other Pseudoxiphophorus lineages, and this initial splitting may be associated to the extension of the Mexican Neovolcanic Plateau at the Punta del Morro site (event used to calibrate our dating analysis). The branch leading to all other Pseudoxiphophorus separated subsequently into two major groups, one comprising those lineages occurring in southern Mexico and Guatemala-Belize, and another with those lineages that extended further southwards to Honduras and Nicaragua. This event took place during the Pliocene, and is likely associated with periods of inundation of the Polochic-Motagua fault area. The Isthmus of Tehuantepec also appears to have been a strong biogeographic barrier triggering cladogenesis in Pseudoxiphophorus. Heterandria formosa (traditionally placed as sister to Pseudoxiphophorus) is not sharing the most recent common ancestor with Pseudoxiphophorus, and is recovered as more distantly related to them. Furthermore, Pseudoxiphophorus bimaculatus (the most cosmopolitan species) is also recovered as a polyphyletic assemblage that appears to comprise those Pseudoxiphophorus that have not been assigned to the other eight, more localized species. All this suggests that Pseudoxiphophorus needs a major taxonomic revision as a whole in order to incorporate all existing diversity.
Journal:
REPORTS OF THE FINNISH ENVIRONMENT INSTITUTE
ISSN:
1796-1718
Year:
2013
Vol.:
25
pp.
47 - 50
Authors:
Almeida, D.; Copp, G.H.; Masson, L.; et al.
Journal:
Aquatic Conservation: Marine and Freshwater Ecosystems
ISSN:
1052-7613
Year:
2012
Vol.:
22
N°:
1
pp.
26 - 35
Journal:
CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE
ISSN:
0008-4301
Year:
2012
Vol.:
90
N°:
8
pp.
1051-1057
Reproduction of pumpkinseed sunfish (Lepomis gibbosus (L., 1758)) in the species' native range often involves cuckoldry, consisting of dominant nest-guarding (parental) males and the participation by small "sneaker" males. However, it remains unknown whether this behaviour occurs in populations of non-native pumpkinseed. Thus, the present study describes the phenotypic features of cuckoldry under contrasting environmental conditions (lentic versus lotic) in southern Europe. Parental and sneaker pumpkinseeds were captured in the summer of 2011 from the River Bullaque (central Spain) and from the Encinarejo Reservoir (southern Spain). No differences in total length were observed in sneaker males, although individuals of ages 1+ and 2+ were significantly predominant in the river and the reservoir, respectively. Parental males were larger and older in the reservoir than in the river. Gonadosomatic and hepatosomatic indices were significantly higher in sneaker than in parental males at both sites. Body condition was lower in sneaker males in the river. Both ingested biomass and the proportion of full stomachs were lower in parental males at both sites, being significant in all cases except ingested biomass in the river. Sneaker males achieved a higher gonadosomatic index than parental males. In contrast, parental males had higher body condition indices than sneakers. Results demonstrate the high ecological plasticity of pumpkinseed sunfish to display natural behaviours out of its native area.
Journal:
The Southwestern Naturalist
ISSN:
0038-4909
Year:
2012
Vol.:
57
N°:
3
pp.
285 - 291
The primary objective was to document the diversity of fishes in Reserva de la Biosfera Barranca de Metztitlan, Hidalgo, Mexico. Samples were collected from 35 localities using electrofishing, nets, and angling, and from local fishermen. A total of 7,290 specimens was collected, representing 16 species (including 4 introduced and 4 translocated). This study adds seven species to the regional fish fauna, five of which are exotic.
Journal:
Environmental Engineering and Management Journal
ISSN:
1582-9596
Year:
2012
Vol.:
11
N°:
6
pp.
1125 - 1131
Construction and management of dams and reservoirs may cause substantial alterations to aquatic habitats. A large dam was constructed in a Pyrenean river (North of Iberian Peninsula) in 2002 and its stress controlled loading (SCL) took place between 2005 and 2009. In this study, hydrochemistry, macroinvertebrate biotic index and fish fauna are compared during the controlled loading preparation process and until 2011 in three stretches along a 40-km downstream section of the river. The most important changes in the hydrochemical parameters were the decrease of temperature and the increase of dissolved oxygen in the first and second sampled stretches. Changes in the fish fauna were also more important in the stretches closer to the dam. Fish fauna was strongly modified into a simplified community dominated by brown trout in the two upper stretches, where cyprinid and nemacheilid species decreased noticeably, especially smallest size classes. These negative effects in the fish fauna should be considered in the design and construction of a reservoir.
Journal:
Environmental Engineering and Management Journal
ISSN:
1582-9596
Year:
2012
Vol.:
11
N°:
6
pp.
1045 - 1048
Journal:
Munibe Ciencias Naturales
ISSN:
0214-7688
Year:
2012
Vol.:
60
pp.
159 - 166
El objetivo de este artículo es determinar la abundancia relativa de martines pescadores
Alcedo atthis L., 1758 nidificantes en ríos de la zona calcárea de la mitad
norte de Navarra. Para ello, durante el periodo de cría de 2007, entre los meses de
abril y agosto, se inspeccionaron tramos de ríos dentro de la citada zona con el fin
de localizar nidos activos y/o parejas nidificantes. Se utilizaron tres metodologías
de censo: (1) localización de nidos, (2) captura de adultos para los que se observaron
signos de reproducción y (3) localización de parejas adultas. Se recorrieron
en conjunto 126,7 km, en los que se hallaron 7 nidos, siendo en consecuencia la
abundancia relativa promedio de 0,06 pareja/km. Si a este valor se suman el número
de parejas seguras, para las que se capturaron uno o los dos individuos con signos
de reproducción, pero no se encontró el nido, la abundancia relativa se incrementa
a 0,07 pareja/km. Si, finalmente, se añaden las parejas que se observaron
durante este periodo y área de muestreo, pero no se capturaron y para las que no
se encontró el nido, la abundancia relativa alcanzaría 0,13 pareja/km. En comparación
con otras zonas tanto del ámbito peninsular como de Europa, la abundancia
relativa obtenida es baja.
Journal:
Acta Ornithologica
ISSN:
0001-6454
Year:
2012
Vol.:
47
N°:
2
pp.
169 - 177
The Common Kingfisher Alcedo atthis is a fish-eating predatory bird that is reported to prey mainly on pelagic, benthic, or both types of fish prey. It still remains unclear whether the species has the capacity to prey indistinctly on all types of fish, regardless of their position within the water column. The aim of our study was to test if kingfishers are able to select particular fish prey or if, by contrast, they feed on the most abundant and accessible fish. We identified the fish prey consumed by kingfishers at 14 nests in total, and also sampled, using electrofishing surveys, fish prey availability on the river stretches where the nests were located. We used Savage's index in order to check whether there was prey selection. Overall, kingfishers preyed upon eight fish species: Bermejuela Acondrostoma arcasii, Bleak Alburnus alburnus, Pyrenean Stone Loach Barbatula quignardi, Ebro Barbel Luciobarbus graellsii, Pyrenean Gudgeon Gobio lozanoi, Ebro Nase Parachondrostoma miegii, Pyrenean Minnow Phoxinus bigerri, and Brown Trout Salmo trutta. The most consumed prey were pelagic species (Pyrenean Minnow and Brown Trout). These results suggest that the Kingfisher preys on pelagic species because of their accessibility and avoids bottom-dwelling species, which may remain hidden from this predator, kingfishers preyed mostly on fish of 50 to 60 mm in length, but mean size values varied prey-specifically, possibly because of the vertical specific distribution in relation to the fish age and species and, finally, prey availability.
Journal:
ANNALES DE LIMNOLOGIE-INTERNATIONAL JOURNAL OF LIMNOLOGY
ISSN:
0003-4088
Year:
2012
Vol.:
48
N°:
3
pp.
289 - 294
The relative importance of biotic and abiotic variables on the Common Kingfisher Alcedo atthis breeding distribution in northern Iberian rivers was quantified through surveys completed in 2007. Eight rivers were surveyed for "positive" and "negative" (control) breeding territories (PBT and NBT, respectively). PBT (N=9) were 3-km river sections with breeding pairs; NBT (N=8) were 3-km river sections close to PBT, where no pairs were found, with apparently similar features to the PBT and one or more cut banks suitable for nesting. Stepwise discriminant analysis (SDA) correctly classified 94.1% of territories and revealed PBT was associated with higher oxygen concentrations, a lower maximum depth and lower proportion of rockfills. Causes and consequences of these findings are discussed.
Journal:
Environmental Engineering and Management Journal
ISSN:
1582-9596
Year:
2012
Vol.:
11
N°:
6
pp.
1111 - 1124
The characterization of fish communities and their relationships with abiotic factors is necessary for a number of environmental management issues. This study aims to analyze the spatio-temporal variability in the structure of fish communities in an undisturbed and unpolluted Pyrenean river in relation to aquatic habitat features. Fish and habitat were sampled seasonally in 2002 at fourteen sampling sites along the Erro River, a tributary of the Ebro basin (Navarra, northern Spain). Fish communities comprised eight native species, and their capture efficiency estimates were high and consistent along the river. Differences between species in estimated capture probability values were related to attributes such as body size and/or abundance, underscoring the importance of using species-specific capture probabilities. The observed low variability of species capture probabilities allows their use as reference values for future population size estimations based on single-run electrofishing surveys in similarly sized rivers. The longitudinal fish species distribution was analyzed by means of separate hierarchical cluster analyses performed on total species' densities and species' densities partitioned by size-classes, both of which displayed similar patterns of fish community composition along the Erro River. The changes on species presence and relative contributions to local fish communities along the river were also evident from diversity indices, which showed strong and significant positive relationships with distance from the source. Seasonal values in diversity indices were also significantly different within sampling sites, indicating that low-order streams support lower diversity and less-structured fish communities because seasonal flow variations lead to high variability in hydrochemical parameters, habitat size and diversity. Two separate canonical correspondence analyses were performed to jointly summarize the variation in aquatic habitat parameters in relation to fish community size structure in terms of densities or biomasses. In both analyses, the first axis was related to the along-river gradient and the second axis accounted for seasonal variation. The relative positions of fish species along the spatio-temporal gradients are in accordance with their habitat preferences described in the Pyrenean area. These results provide a framework for understanding how the spatio-temporal variations of reach-scale aquatic habitat features structure fish communities in a Pyrenean river with low anthropogenic disturbance.
Journal:
JOURNAL OF APPLIED ICHTHYOLOGY
ISSN:
0175-8659
Year:
2012
Vol.:
28
N°:
4
pp.
667 - 670
Body length and weight relationships were estimated for sixteen native freshwater fish species (ten Characidae, three Loricariidae, two Heptapteridae and one Astroblepidae, mainly small-sized fish) collected in the Andean piedmont Hacha River (Caqueta, Colombia) by electrofishing. These are the first lengthweight and lengthlength parameters reported for the species, which are mostly endemic to the Amazonian basin. Maximum lengths in eight of the sixteen studied species are also reported. Knowledge of this biometric data and their relationships can be relevant in the management and conservation of the local fish and fisheries.
Journal:
JOURNAL OF APPLIED ICHTHYOLOGY
ISSN:
0175-8659
Year:
2012
Vol.:
28
N°:
5
pp.
818 - 822
The present study describes the size at first sexual maturity, fecundity, lengthweight (LWRs) and lengthlength relationships (LLRs) of the pool barb, Puntius sophore, using data obtained from different geographical locations in Bangladesh. A total of 905 specimens were caught by traditional fishing gear from March 2010 to February 2011. Additionally, a total of 121 females were collected from a commercial catch of the Padma River during JuneJuly 2011 to estimate size at first maturity and to determine fecundity. Total length (TL), fork length (FL) and standard length (SL) were measured with digital slide calipers. Individual body weights (BW) were determined for all specimens, and gonad weights (GW) from 121 females were weighed to an accuracy of 0.001 g. The female gonadosomatic index (GSI) was calculated as [GSI (%) = (GW/BW) x 100]. Female size at first maturity was estimated using GSI and TL as indicators, and estimated as 5.00 cm TL in the Padma River. Specimens larger than 5.00 cm TL were used to determine fecundity. Mean total fecundity was 5300 +/- 2700, ranging from 1580 to 16590. A positive exponential correlation was recorded between total fecundity and total length (r2 = 0.421). Relative fecundity ranged from 466 to 4036 (mean 1100 +/- 580) in the Padma River. The LWR of pooled data for sexes combined was estimated as BW = 0.0155 TL2.98 as ancova revealed no significant differences in LWRs between rivers (P > 0.05). All LLRs were highly correlated (r2 > 0.983; P < 0.001), and ancova analyses further indicated that LLRs did not differ between rivers (P > 0.05). These results will help in further studies on the population assessment of the species.
Journal:
Journal of Fish Biology
ISSN:
0022-1112
Year:
2011
Vol.:
79
N°:
6
pp.
1563 - 1591
Authors:
Masson, L.; Almeida, D.; Tarkan, A.S.; et al.
Journal:
JOURNAL OF APPLIED ICHTHYOLOGY
ISSN:
0175-8659
Year:
2011
Vol.:
27
N°:
5
pp.
1286 - 1290
The identification of fish species from head bone remains is employed in various sciences, including archaeology, paleontology and field ecology, with the estimation of fish size from biometric relationships being useful in the assessment of predation pressure exerted by increasing numbers of piscivorous species (e.g. Eurasian otter Lutra lutra and great cormorant Phalacrocorax carbo). This is particularly relevant for crucian carp, Carassius carassius, which is in decline in Europe due to changes in land use and to increasing numbers of non-native Carassius species (i.e. goldfish C. auratus, gibel carp C. gibelio), which hybridize with C. carassius. However, diagnostic keys and biometric relationships are lacking for C. carassius and its most common hybrids, crosses with C. auratus. The present paper addresses this gap in knowledge, providing diagnostic keys and biometric relationships for the head bones of all Carassius species found in Europe as well as for C. carassius x C. auratus hybrids. All bone size to body length relationships were statistically significant. Similarly, all bone size to body weight relationships were significant for C. carassius, C. auratus, and C. gibelio, but none were significant for C. carassius x C. auratus hybrids. Diagnostic structures were found to distinguish easily between the Carassius species and hybrids, which will assist in determining the identity and sizes of prey found in faecal and archaeological remains.
Journal:
AQUATIC INVASIONS
ISSN:
1798-6540
Year:
2010
Vol.:
5
N°:
3
pp.
291 - 296
This paper extends the knowledge of the geographical distribution of non-native freshwater fishes in the Ebro River basin (Spain). More than two hundred surveys were carried out since 2000, and thirteen non-native fish species were collected on fifty-eight occasions. The spread of most of the recorded non-native species seems to be a consequence of illegal introductions related to sport fishing activities and the subsequent natural dispersal. Their presence could impact natural populations of Iberian native -mostly endemic- freshwater fish species, through direct predation and competition for niche and/or trophic resources.
Journal:
HIDROBIOLOGICA
ISSN:
0188-8897
Year:
2010
Vol.:
20
N°:
2
pp.
185 - 190
A population of blackfin goodea Goodea atripinnis was encountered in the Metztitlan Canyon Biosphere Reserve (Panuco Basin, Hidalgo, Mexico). This species has a wide distribution across the Pacific Slope of Mexico, including the Lerma-Grande de Santiago basin, Ameca River, Magdalena Lake and the Balsas and Armeria basins. Biometric data were used for identification and comparison to those of other putative members of the genus. The taxonomic identification and systematic position of this species are discussed. Goodea luitpoldii and G. gracilis are confirmed as synonyms with G. atripinnis. Comments on conservation implications of this species and their Panuco Basin populations are given.
Journal:
MANAGEMENT OF BIOLOGICAL INVASIONS
ISSN:
1989-8649
Year:
2010
N°:
1
pp.
13 - 33
The consideration of non-native freshwater fish species in the management plans of 18 Biosphere Reserves is evaluated. Additionally, impacts caused by introduced freshwater fish species are described. Some measures to alleviate the ecological effects of fish species introductions are proposed, while paying attention to local development as well. The introduction of non-native species may have negative consequences for the ecosystems. The analysis of the management plans of the Reserves confirms that non-native freshwater fish species sometimes are not considered in the action plans of the area. Biosphere Reserve's management plans should consider the presence of alien species, with the aim to preserve biodiversity.
Journal:
AQUATIC INVASIONS
ISSN:
1798-6540
Year:
2010
Vol.:
5
N°:
3
pp.
229 - 230
