It’s a common storyline in many a disaster movie, but it appears that the phenomenon of large predators getting sighted in places far removed from their natural habitat is becoming more common than ever before, as a result of conservation efforts. But unlike those movies, where predators show up on beaches and in other unexpected places and attack people, this real-life trend is actually a good thing for both animals and humans alike, according to the authors of a new study.
In a meta-analysis published Monday in the journal Current Biology, a team of researchers noted that several large predators, including alligators, mountain lions, and sea otters, are re-colonizing the ecosystems that were once targeted by humans, instead of finding new habitats to make their home. According to lead author Brian Silliman, an associate professor of marine conservation biology at Duke University’s Nicholas School of the Environment, this is an increasing trend, where it can no longer be called unusual for alligators to show up at unusual places such as beaches and coral reefs.
“It’s not an outlier or short-term blip. It’s the old norm, the way it used to be before we pushed these species onto their last legs in hard-to-reach refuges. Now, they are returning.”
As stressed by Science Daily, the meta-analysis conducted by Silliman and his fellow researchers mainly involved the “synthesis” of previous data from earlier scientific studies and government reports. After crunching the numbers and isolating similarities in these previous findings, the team concluded that conservation initiatives have led to alligators, sea and river otters, gray wolves, mountain lions, orangutans, and other large predators appearing more often in “novel” habitats, as opposed to conventional ones.
Based on his team’s meta-analysis, Silliman said that the return of these predators to areas where their populations once declined steeply due to human hunting activities, or habitats that were once considered “off-limits,” goes against a tried-and-true large animal ecology principle — that animals choose where they make their home by virtue of their being “habitat specialists.” He cited several examples of how this principle works, including alligators choosing to live in swamps, orangutans favoring “undisturbed” forest, and marine mammals calling the polar waters their home.
“But this is based on studies and observations made while these populations were in sharp decline,” Silliman continued.
“Now that they are rebounding, they’re surprising us by demonstrating how adaptable and cosmopolitan they really are.”
All in all, Silliman believes that the trend of large predators showing up where one would least expect them to has benefits to both human and animal populations, as pointed out by the Daily Mail. Sea otters, which were referenced multiple times in the meta-analysis, feed on Dungeness crabs, a species that is known to eat too much of the sea slugs that protect estuarine seagrass beds from being overcome by epiphytic algae. Silliman said that initiatives to protect such seagrass beds would normally cost “tens of millions of dollars,” which means that sea otters are saving taxpayers a ton of money by protecting the beds in their own unique way.