While Californians mourn the death of the famous P-22 Mountain Lion, work continues on Cross the huge bridge of wildlife in Los Angeles County that will connect two landscapes that are divided by one of the busiest highways in the country.
Perhaps the lasting legacy of the cougar that was Capture and euthanasia By California Fish and Wildlife officials after his health began to fail rapidly, is the attention his story brought to the plight of animals who found themselves besieged on all sides by urban sprawl.
That’s why in September 2022, Gov. Gavin Newsom Sign legislation To require the state to identify sites where animals encounter barriers separating them from moving freely and to prioritize building or converting existing infrastructure to allow them to cross more safely.
Animal welfare groups have applauded the decision, but researchers say special care will be needed to ensure wildlife crossings make sense for the animals that will use them.
Some animals may actually fear using wildlife crossings, a recently published study by researchers at the University of California found, so designers will need to take this into account when planning any new crossings.
“We know species use them, but sometimes they have to be tailored to specific species because different species see open areas or habitats at crossings differently,” said Dan Blumstein, professor of ecology and evolutionary biology at UCLA.
Blumstein’s team studied a wildlife tunnel crossing in Alberta, Canada, to see how animals used it, if they did at all.
Videos from the Wildlife Crossing have shown that some deer and elk near the Wildlife Crossing may switch from foraging to fearful or fleeing altogether when passing cars. Animals that appeared more fearful or alert were less likely to use the crossing.
Other animals, including some ferrets, will likely pass by without giving them a second thought.
In the end, what they found is that there is no universal set of behaviors for animals, so there is no one-size-fits-all solution for designing a wildlife expressive.
“At the end of the day, we found that those animals that were foraging seemed less concerned with vehicular traffic than those that were more alert, which is kind of saying that individuals behave differently at these wildlife crossings,” Blumstein said.
Part of it, the researcher said, comes down to whether or not a specific animal views the habitat structure as protective or hindering. Animals that consider things like bushes and bushes to be safe places will use cover, but other animals may think these same obstacles are dangerous.
“In these wildlife crossings, different species behave differently, and we need to think about designing the crossings, as others have already realized, we need to think about designing the crossings to be kind of specific to the species that you’re dealing with,” he said.
Even closely related species—in his example, wallabies and kangaroos—would interpret different landscapes and vegetation in opposite ways. Wallabies value coverage; Kangaroos prefer open space.
While there wouldn’t be any kangaroos crossing Highway 101, the logic remains the same: the animals see different things as safe or dangerous.
He added that architects and researchers designing wildlife crossings need to have a good understanding about the species they are trying to cross and then design a structure that is “appealing to many species.”
As for the Wallis Annenberg Wildlife Crossing at Agoura Hills, Blumstein said the scale of the project could allow for many “micro-habitats” to accommodate the needs of multiple species.
Blumstein called it a bold idea to try to reconnect fragmented habitats, which comes at a steep price.
Los Angeles County Transit will be at a price More than 90 million dollarsbut not building it also has a cost.
“We know there are costs to isolation, we can see that with genetic mutations and inbred animals and mountain lions in Los Angeles. And, you know, some will use this and that will lead to gene flow and that will be a good thing,” Blumstein said. “We mess with Mother Nature at our own risk and the solutions are often expensive, but wildlife crossings and wildlife corridors have been very successful elsewhere, and I expect they will be successful here on some level.”