A new study has shed light on how several species of marine mammals in the world are on the verge of extinction, due to climate change, pollution and other human activities.?
The study (published in Endangered Species Research) was conducted by a team from the University of Exeter which looked at 126 species that included whales, dolphins, sea lions, manatees, dugongs, sea otters and polar bears. They discovered that at least 25 percent of these species have been categorised as threatened.
The study also states that 98 percent of marine mammal species are at risk on some level across 56 percent of the ocean, mostly in coastal waters.?
One of the main reasons for this is human fishing activities. The study reveals several species of cetaceans like vaquita and North Atlantic right whale Eubalaena Glacialis and pinnipeds have been almost pushed to extinction because of fisheries bycatch.?
Another factor contributing to this is pollution -- both water and noise. While we¡¯ve seen how plastic or chemical waste in water affects marine life, noise pollution can be equally harmful.
Apparently, noise pollution is known to traumatise behavioural responses, causing stress that causes the mammals to injure themselves. It can also impact ecologically relevant sounds necessary for their communication.?
Dr Sarah Nelms, of the Centre for Ecology and Conservation on Exeter¡¯s Penryn Campus in Cornwall, explains, ¡°We have reached a critical point in terms of marine mammal conservation. Very few marine mammal species have been driven to extinction in modern times, but human activities are putting many of them under increasing pressure.¡±
She added, ¡°Our paper examines a range of conservation measures ¨C including Marine Protected Areas (MPAs), bycatch reduction methods and community engagement ¨C as well as highlighting some of the species that are in urgent need of focus.¡±
According to the researchers, 21 percent of the marine mammal species are categorised as ¡®data deficient in the IUCN Red List, indicating that there isn¡¯t enough data available to better understand their conservation status. This in turn makes it more challenging for conservationists to identify which species need the protection and the actions necessary to save them.
Professor Brendan Godley, who leads the Exeter Marine research group, said: ¡°To continue conservation successes and reverse the downward trend in at-risk species, we need to understand the threats they face and the conservation measures that could help.¡±
He added, ¡°Technology such as drone and satellite imaging, electronic tags and molecular techniques are among the tools that will help us do this. Additionally, sharing best practice will empower us ¨C and this is why we are so proud to be part of such a large and international group for this project.¡±