Assessing the functional impact on ecosystems of Sundaland freshwater species loss

Anthropogenic threats to freshwater fishes drive impacts on functional richness, redundancy and vulnerability in ecoregions of Sundaland

Data resources used via GBIF : 893 species
Macrognathus circumcinctus
Half-banded spiny eel (Macrognathus circumcinctus) observed in Kuala Berang, Terengganu, Malaysia by tansh91. Photo via iNaturalist (CC BY-NC 4.0)

Not only a terrestrial biodiversity hotspot, the biogeographical region of Sundaland in southeast Asia is also a global hotspot for freshwater diversity. Large-scale agricultural conversion of rainforests poses a major threat to freshwater fishes and the ecosystems they help support.

By assessing functional richness, redundancy and vulnerability of Sundaic freshwater fishes, researchers behind this study give insights into the current status of ichthyofaunal diversity and potential impacts of species loss on ecosystems.

Compiling knowledge from a wide range of sources—including GBIF—of all occurring fishes across 13 ecoregions, the authors describe functional traits for 893 species. The distribution of trait entities varies from less than 30 per cent of the total variation in trait entities in Java to more than 85 per cent in the Malay peninsula.

When modelling loss of extinction-prone species, they show a general pattern of accelerating impacts on functional diversity. With low levels of functional redundancy and thus high vulnerability to impacts of species loss, the Malay Peninsula Eastern Slope is singled out as the most urgent target for conservation efforts.

Original article

Chua KWJ, Tan HH and Yeo DCJ (2019) Loss of endemic fish species drives impacts on functional richness, redundancy and vulnerability in freshwater ecoregions of Sundaland. Biological Conservation. Elsevier BV 234: 72–81. Available at: