Wildlife & Biodiversity

Scientists look into the past to identify locally threatened fish

The researchers reconstructed species’ occurrences by combining modern underwater transect surveys and catch assessments with historical records

 
By DTE Staff
Last Updated: Friday 15 February 2019
Fish
The White Spotted Grouper, a fish found from East Africa to the Pacific, and is thought to be of 'Least Concern' but could be extinct locally. Credit: Getty Images The White Spotted Grouper, a fish found from East Africa to the Pacific, and is thought to be of 'Least Concern' but could be extinct locally. Credit: Getty Images

Marine scientists from the University of Queensland in Australia, conservation non-profit, Wildlife Conservation Society (WCS) and other groups have developed a methodology to assess fish stocks that combines new data with archaeological and historical records — some dating back to the 8th Century CE.

In a study conducted along the coast of Kenya, the researchers reconstructed species’ occurrences by combining modern underwater transect surveys and catch assessments with historical records that included observations from 18th century naturalists and data from archaeological sites including ancient middens (Prehistoric refuse heap which marks an ancient settlement, chiefly containing bones, shells, and stone implements) dating back more than a thousand years.

The study, titled ‘Identifying species threatened with local extinction in tropical reef fisheries using historical reconstruction of species occurrence’, has been published in the latest issue of the journal PLOS ONE.

The study has found that some species, previously thought to be “Least Concern,” “Unevaluated,” or “Data Deficient” on the International Union for Conservation of Nature’s Red List of Threatened Species, were actually threatened with local extinction. These included species of groupers, trevallies, rubberlips, and other fish. Further, the historical data identified species that were previously exploited in the region and are most likely locally extinct.

“Local extinction rates are increasing among marine species,” note the authors in their concluding remarks. “Some of these species are likely to play important roles in ecological processes and services that may erode as they disappear. The first step towards avoiding local extinction is providing status information at a scale where decision-makers and managers can intervene,” they add.

This is where the authors say their new method, which is inexpensive, could be important in filling in knowledge gaps in species extinction assessments.

Subscribe to Weekly Newsletter :
Related Stories

India Environment Portal Resources :

Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.