"It's important to evaluate such broad legislation," says co-author Caitlin Campbell, a UVM student.
"A lot of people think that the hard part was getting it passed through Congress, but in reality you have to make sure that big protective measures like this actually are effective," she says. "This paper shows that this act is doing its job."
The research team Campbell; Joe Roman in UVM's Gund Institute for Ecological Economics; Irit Altman from Boston University; Meagan Dunphy-Daly and Andrew Read from Duke University; and Michael Jasny from the Natural Resources Defense Council gathered hundreds of data sets from around the world, including from NOAA, Canadian agencies, and the IUCN. Their goal was to get an accurate picture of population levels and trends of more than two hundred stocks of marine mammals from the Pantropical Spotted Dolphin to the West Indian Manatee.
The team concluded that for many of these animals there simply aren't enough data. For seventy-one percent of the stocks they identified, they couldn't say which way the population was heading, up or down. "There isn't enough research," Roman says.
But for the ones they could evaluate, they found that nineteen percent of stocks were increasing, while five percent were stable and only five percent were declining.
Another fundamental conclusion of this research: "stopping harvesting these mammals, stop fisheries bycatch, stop killing them and many populations bounce back," says Roman. Marine mammals are long-lived "so it's going to take decades, maybe longer for populations to rebound," he says, "but it seems the trends are increasing."
In 1934, trends were de
|Contact: Joshua Brown|
University of Vermont