There are computer models that have been successfully used to determine the status of terrestrial mammals. These predictive models incorporate a variety of factors including habitat, body mass, rate of reproduction, social group size, and more. Each factor is weighted based on the particular species. All have an impact on how well a particular species survives and what their future may have in store when certain factors change, such as pollution, loss of habitat, or climate change.
Marine mammals currently include 128 different species from whales and dolphins to seals and sea lions to manatees and dugongs. And right know the status of nearly 40 percent of them are unknown due to a lack of data. Even with that limitation, the IUCN Red List considers 25% as endangered. However, this new study's predictive model pushes that figure closer to 37 percent.
While factors such as a slow rate of reproduction, a small geographic area of distribution, or a tendency toward small social groups, when combined with environmental factors could have an effect on predicted risks of extinction, according to Dr. Ana Davidson, lead author from the University of New Mexico, “species’ traits were the most important predictors of risk overall, underscoring the importance of understanding species’ basic biologies and ecologies, which is unfortunately lacking for many marine mammals, even some of the most well-known groups like dolphins.”
A press release issued by the University of New Mexico reported, "Using their predictive model, the team also generated new maps of species at risk. They illustrate that at-risk species mostly occur in coastal regions and in productive areas of the open ocean, which are also areas subject to high levels of human impact. The models identified 13 global hotspots where high numbers of at-risk species occur, and show how they overlap with leading human impacts on the world’s oceans (fishing, shipping and pollution, and climate change) and Marine Protected Areas."
“We found that three-quarters of marine mammal species experience high levels of human impact in their environment, and these include the cumulative effects of numerous factors, including fishing, shipping, pollution, sea surface temperature change, ocean acidification, invasive species, oil rigs, and human population density,” said Dr. Alison Boyer, another researcher from the University of Tennessee involved in the study.This new research adds to a growing body of work that supports the concept of Marine Protected Areas and other recognized marine parks or sanctuaries, while also recognizing the need for more international management policies. There is much to be learned about marine mammals, more than most people think. However, studies like this make the case that we cannot just sit on our hands and wait for data on each and every species to arrive. Predictive models that have been shown to be of value on land can also show that time is running out for marine mammals as well if decision makers choose to hesitate and strong preventative measures are not taken.
Source: UNM Today