LOS ANGELES — After years of dusty, dry hillsides, much of Southern California has turned green from record-breaking rain and snow this winter, which wildlife experts say has already started to improve habitats and populations for certain species - a trend they expect to reverberate through the entire landscape.
That is likely to mean the region will be populated with more squirrels, rabbits, rats and snakes - although, in some cases, it could take several months or longer to see the resulting surge in wildlife.
“This year had just been transformative throughout the region, just the amount of growth of everything,” said Daniel Cooper, a senior conservation biologist at the Resource Conservation District of the Santa Monica Mountains. “Everything is just exploding right now.”
That new growth is evident across the region, providing an increase of ground cover, grazing and shelter for many species, say wildlife and park officials who have already noticed an increased number of some animals, such as the kangaroo rat in northern Los Angeles County and the red-tailed hawk countrywide.
“We are seeing a lot of beautiful growth,” said Noemi Navar, the regional park superintendent at San Dimas Canyon Nature Center, part of the L.A. County Department of Parks and Recreation. “We see more bushes, that means more ground coverage for rabbits or squirrels or things like that, which then moves up the food chain.”
It’s still unclear just how dramatic or long term these changes could be for the region’s vast and diverse ecosystem, but prior trends and research show that it’s likely many native species could see increasing populations this season or next, following the rise in precipitation.
Already this season, volunteers across Los Angeles have seen a jump in sightings of red-tailed hawks and great-horned owls, Cooper said, citing preliminary reports from this year’s volunteer-led L.A. Raptor Study, which monitors nests for falcons, owls and hawks.
“At the height of the drought ... we had a lot of red-tailed hawk nests, or territories, being abandoned,” Cooper said. “This year, we saw a lot of those inactive territories miraculously become active again.”
While he can’t definitely tie that change to the weather just yet, he pointed out that the two avian species prey on ground animals, such as rabbits, squirrels and snakes, which tend to be more active when there’s more foliage for them to eat.
“You can’t really track rabbits all over L.A., but 100 hawk nests - we’re monitoring (those) every week,” Cooper said. “It’s turned into an interesting way of taking the pulse of urban L.A. wildlife.”
“These things live and die by the weather,” he added.
Rattlesnakes and rodents
While rattlesnake season - specifically the Southern Pacific rattlesnake - begins yearly in April, it’s not yet clear if the animals will be more prevalent this year, said Jessica West, a human-wildlife conflict specialist for California Department of Fish and Wildlife in Southern California.
However, recent research found that human-snake interactions in California tend to increase about 18 months after significant precipitation, according to a 2018 study that looked at 20 years’ worth of snake bites in the state.
“I think that we’re going to see the biggest impact of snake bites probably next summer, next spring and summer,” said Grant Lipman, one of the study’s authors.
While the study didn’t look at the cause of these increases in bites, Lipman said it’s likely “a supply-and-demand-type relationship.”
“We know that in high-precipitation areas, you have an increase in rodents, because they can forage more easily for food,” said Lipman, a former professor of medicine at Stanford and now the founder of an outdoor health app. “And those are going to be the primary food source for snakes.”
At Devil’s Punchbowl Natural Area in the Antelope Valley, park superintendent Jonathan Numer said his teams have already noticed a surge in kangaroo rats, which he said reproduce much quicker than other species, like reptiles or birds.
“Snakes and animals like that, it will take a year” to see their population drastically change, Numer said.
But he said his park rangers have noticed other changes since the storms, including deer coming to lower elevations to escape the snow on the mountains.
“When there’s a lot of snowpack, you can kind of expect wildlife to head into lower elevation areas,” West said. She said she wouldn’t be surprised if other animals, like big horn sheep, also moved to lower regions, followed by their predators, like mountain lions.
“But with streams flowing again, we’re hoping that will pull a lot of wildlife back to those natural resources,” said Navar. Often larger animals - like bears, bobcats and mountain lions - have sought water in urban areas or from residents’ pools during droughts, but she said she’s hopeful they will be able to again rely on natural water sources.
Among the other potential benefits from the excess rain is likely a delayed and longer spring flower season, said Kelley Brugmann, a resource specialist with Orange County Parks and Recreation.
“I think the length of the flower bloom will be a bit longer compared with years past,” Brugmann said. The season for California poppies is typically from February through April, but this year it’s been pushed back, she said.
“I’m still seeing a lot of poppies pop up now and I’m expecting we’ll see them go through early May,” Brugmann said. And that trend is likely to stretch through the summer, hopefully seeing less of the “vegetation vacation” that the region usually sees, she said.
“This year I suspect we’ll still have pretty strong showing of the paint palette just because of the deep moisture (we saw),” Brugmann said.
Cooper said he’s also hopeful the increase in water could be positive for some birds that have put off breeding during years of drought, like the endangered California gnatcatcher, or struggled to procreate during the dry period, like the meadowlark.
They were “probably really struggling to nest during the drought and are just going to rebound,” Cooper said.
Cooper said he’s also hopeful some amphibians could get a boost with such increased water, like the western toad, which often breeds in drainage systems across Griffith Park — or even the more rare Western spadefoot toad, which has been found in recent years in the Chatsworth Nature Preserve.
Lipman also pointed out that the heavy rains could mean a more active tick season for some parts of California, mostly in the north, as some research has found.
CDFW have also said that the recent rains are likely to help improve salmon populations, though in about three years’ time, after this year reported record low numbers.
To help scientists and park officials track all these changes and also report wildlife sightings, Navar recommended people download the app iNaturalist, which can also help identify species and create records of wildlife so that trends and changes and be analyzed years from now. She asked that while people learn and explore nature, they remember to be respectful, stay on trails and keep appropriate distance from wildlife.
“People are just excited to be outside, we’ve all been cooped up for way too long,” Brugmann said. “With so many crowds out on the trails, it’s important to be mindful, not just of wildlife, but to each other.”