Dataset Information

Evidence of indiscriminate fishing effects in one of the world's largest inland fisheries.

ABSTRACT: While human impacts like fishing have altered marine food web composition and body size, the status of the world's important tropical inland fisheries remains largely unknown. Here, we look for signatures of human impacts on the indiscriminately fished Tonle Sap fish community that supports one of the world's largest freshwater fisheries. By analyzing a 15-year time-series (2000-2015) of fish catches for 116 species obtained from an industrial-scale 'Dai' fishery, we find: (i) 78% of the species exhibited decreasing catches through time; (ii) downward trends in catches occurred primarily in medium to large-bodied species that tend to occupy high trophic levels; (iii) a relatively stable or increasing trend in catches of small-sized species, and; (iv) a decrease in the individual fish weights and lengths for several common species. Because total biomass of the catch has remained remarkably resilient over the last 15 years, the increase in catch of smaller species has compensated for declines in larger species. Our finding of sustained production but altered community composition is consistent with predictions from recent indiscriminate theory, and gives a warning signal to fisheries managers and conservationists that the species-rich Tonle Sap is being affected by heavy indiscriminate fishing pressure.

SUBMITTER: Ngor PB

PROVIDER: S-EPMC5997758 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Evidence of indiscriminate fishing effects in one of the world's largest inland fisheries.

Ngor Peng Bun PB McCann Kevin S KS Grenouillet Gaël G So Nam N McMeans Bailey C BC Fraser Evan E Lek Sovan S

Scientific reports 20180612 1

While human impacts like fishing have altered marine food web composition and body size, the status of the world's important tropical inland fisheries remains largely unknown. Here, we look for signatures of human impacts on the indiscriminately fished Tonle Sap fish community that supports one of the world's largest freshwater fisheries. By analyzing a 15-year time-series (2000-2015) of fish catches for 116 species obtained from an industrial-scale 'Dai' fishery, we find: (i) 78% of the species ...[more]

PMID: 29895943

Similar Datasets

Project description:A primary aim of historical biogeography is to identify the causal factors or processes that have shaped the composition and distribution of biotas over time. Another is to infer the evolution of geographic ranges of species and clades in a phylogenetic context. To this end, historical biogeography addresses important questions such as: Where were ancestors distributed? Where did lineages originate? Which processes cause geographic ranges to evolve through time? Allium subgenus Anguinum comprises approximately twelve taxa with a disjunct distribution in the high mountains from south-western Europe to eastern Asia and in northeastern North America. Although both the systematic position and the geographical limits of Anguinum have been identified, to date no molecular systematic study has been performed utilizing a comprehensive sampling of these species. With an emphasis on the Anguinum eastern Asian geographical group, the goals of the present study were: (i) to infer species-level phylogenetic relationships within Anguinum, (ii) to assess molecular divergence and estimated the times of the major splits in Anguinum and (iii) to trace the biogeographic history of the subgenus. Four DNA sequences (ITS, matK, trnH-psbA, rps16) were used to reconstruct the phylogeny of Allium subgen. Anguinum RbcL sequences were used to estimate divergences time for Allium, and sequences of ITS were used to estimate the divergence times for Anguinum and its main lineages and to provide implications for the evolutionary history of the subgenus. Phylogenetic analyses for all Allium corroborate that Anguinum is monophyletic and indicate that Anguinum is composed of two sister groups: one with a Eurasian-American distribution, and the other restricted to eastern Asia. In the eastern Asian geographical group, incongruence between gene trees and morphology-based taxonomies was recovered as was incongruence between data from plastid and nuclear sequences. This incongruence is likely due to the combined effects of a recent radiation, incomplete lineage sorting, and hybridization/introgression. Divergence time estimates suggest that the crown group of Anguinum originated during the late Miocene (ca. 7.16 Mya) and then diverged and dispersed. Biogeographic analyses using statistical dispersal-vicariance analysis (S-DIVA) and a likelihood method support an eastern Asia origin of Anguinum It is inferred that in the late Pliocene/Early Pleistocene, with cooling climates and the uplift of the Himalayas and Hengduan Mountains, the ancestor of the eastern Asian alliance clade underwent a very recent radiation.

Dataset Information

Evidence of indiscriminate fishing effects in one of the world's largest inland fisheries.

Publications

Evidence of indiscriminate fishing effects in one of the world's largest inland fisheries.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets