Lisanne Petracca researches how to rebuild populations of threatened species, from gray wolves and ocelots to tufted puffins
For Lisanne Petracca, A06, it’s not about what type of big cat you are—or even if you’re a cat at all. From jaguars, lions, and ocelots to wolves and puffins, Petracca has dedicated her career to researching the population dynamics of threatened wildlife species, in the hope that they can return and help heal our ecosystems.
My, What a Vulnerable Range You Have
Take gray wolves, a population that hunting and habitat loss wiped out in the Lower 48 by the early 1900s. Without wolves at the top of the food chain, elk and deer populations surged, consuming so much native vegetation that species from butterflies to beavers and songbirds to salmon were harmed.
Fortunately, after nearly a century of absence from Washington state, wolves crossed over from Canada and began to repopulate the Pacific Northwest. Enter Petracca, who, as a postdoctoral scientist at the University of Washington, analyzed data on how these iconic predators, and their habitat, might return from the brink.
“Being able to see lions, leopards, and cheetah up close was a transformative experience for me.”
Petracca looked at how many wolves were living in Washington from 2009 to 2020 and tried to predict the areas they’re likely to return to over the next 50 years. Those include Washington’s Southern Cascades and Northwest Coast—places to which the animals haven’t yet migrated, due to a major highway bisecting the state.
“With no resident pack on the other side of I-90, the big question was, ‘When will at least four breeding pairs of wolves get there?’” Petracca said, referring to the number of animals considered adequate to meet the state’s recovery goals.
Using data provided by Washington’s Department of Fish and Wildlife on pack sizes, reproductive rates, and habitat and breeding locations from GPS collars, Petracca modeled the probabilities of where the wolves might spread and settle, based on their previous habitat choices and movement rates.
The good news: Two different simulations predict wolves will reinhabit the Southern Cascades and Northwest Coast by 2030.
The bad news: Without a steady influx of wolves from neighboring states and Canada, wolves likely won’t reclaim Washington as a permanent home. “We found that, if wolves do not continue to come into the state as they’ve been doing, we will not be able to maintain a sustainable population,” Petracca said.
While wolves are off-limits to Washington hunters, the same isn’t true in neighboring states. “Idaho and Montana have greatly increased the number of wolves that can be harvested, and that clearly will have repercussions for the population immigrating into Washington,” Petracca said.
Her findings are informing Washington biologists’ efforts to find new packs and maintain habitat connectivity within the state, including monitoring new and planned wildlife crossings across I-90.
“Wolves don’t respect state borders,” Petracca said. “Given that the Washington population is only as good as the Northwest population as a whole, retaining those connections is key.”
The Age-Old Question: Canines or Cats?
But wolves weren’t Petracca’s first love. She originally caught big-cat fever during a semester abroad in Tanzania while earning her B.S. in environmental studies, biomedical engineering, and psychology at Tufts.
“Being able to see lions, leopards, and cheetah up close was a transformative experience for me,” she said.
She further scratched the itch with a master’s degree in environmental management from Duke, followed by more than a decade at the nonprofit Panthera, working to conserve jaguars in Belize and lions in Zimbabwe. Meanwhile, she was also pursuing her Ph.D. in ecology from SUNY College of Environmental Science and Forestry and realized she wanted to lead research into species conservation. Petracca charted a right turn into academia, studying first wolves and now what might be the anti-apex predator: the tufted puffin of the most remote reaches of North America’s West Coast.
These days, Petracca is continuing her puffin research for the University of Washington’s Quantitative Conservation Lab from points south. In January, she joined Texas A&M – Kingsville as an assistant professor of carnivore ecology working with the Caesar Kleberg Wildlife Research Institute and the East Foundation to bring back the ocelot, a small spotted wildcat.
Dependent on scrub habitat increasingly lost to development and farming, fewer than 80 ocelots are estimated to remain in southern Texas, and many are being killed by cars. Petracca is studying the long-term population dynamics of ocelots in Texas, as well as how ocelot, mountain lions, coyotes, and bobcats navigate the border wall fragmenting their native ranges. She is also maintaining an ocelot captive breeding facility to help restore wild populations.
One thing ocelots, puffins, and wolves have in common? They all face formidable challenges in a human-altered world. Petracca believes we can still save them, if we act. She cited the optimism she felt last summer, while visiting the Aleutian Aiktak Island, home to more than 100,000 tufted puffins.
“There were so many, the sky was absolutely filled with puffins,” she said. “It reminded me there is still so much hope for these spectacular creatures.”