(CN) – Marine wildlife populations like Florida manatees and California sea otters are bouncing back in protected habitats throughout the United States, according to a study from the Center for Biological Diversity.
Several species of whales, seals, sea lions and sea turtles experienced population growth after being listed under the Endangered Species Act and given habitat protections.
While the ocean is vast and varied, the study focused on 23 marine mammals and nine sea turtles to gauge the effectiveness of the Endangered Species Act.
The selected species were chosen because of the high-quality data available, according to Abel Valdivia, an ocean scientist with the Center for Biological Diversity who wrote the study.
Some species, like the Hawksbill turtle found in the Atlantic Ocean or the Humpback whale found in Hawaii, have been listed under the Endangered Species Act for more than 40 years. Those two distinct population segments saw significant increases and some species of humpback whale were even delisted due to their recovery in the wild.
Overall, 78 percent of the studied populations grew and just two species – the Southern Resident killer whale found
in the Northeastern part of the North American Pacific Ocean and the Hawaiian monk seal – declined while listed under the act.
Extinction risks for sea life varies across the planet, but the study says overfishing, habitat loss and degradation, pollution and climate change are the primary causes of impact to marine populations.
Thanks to the act, vessels are required to slow down when approaching whales in the ocean and fishing for sea turtles is banned.
The study did show that species listed for more than 20 years experienced greater recovery rates, while those that were more recently listed did not experience such results.
Currently the study is under review by the scientific journal PLOS ONE.