Connect with us

Animals

Mountain Lions Pushed Out By Wildfires Take More Risks

Published

on

mountain-lions-pushed-out-by-wildfires-take-more-risks

Mountain lions have no interest in people, or the built-up areas we enjoy. But after a 2018 wildfire in California, local lions took more risks, crossing roads more often and moving around more in the daytime, scientists report October 20 in Current Biology. It’s another way the effects of human development could be putting pressure on vulnerable wildlife — in this case, potentially pushing them toward our bumpers.

The Woolsey Fire began near Los Angeles on November 8, 2018, and burned more than 36,000 hectares in the Santa Monica Mountains. Nearly 300,000 people evacuated, and three people died. Animals fled the fire too, including the local mountain lions (Puma concolor). The fire was a tragedy, but also a scientific opportunity, says Rachel Blakey, a global change biologist at UCLA. Many of the lions wore tracking collars, allowing scientists to study how the fire changed their behavior.

Of the 11 collared cougars in the area at the time, nine made it to safety during the fire itself. “They have really large home ranges, so it’s nothing to them to be able to cover many kilometers in a day,” Blakey says.

No matter how much they moved, the mountain lions avoided people. One collared cat, P-64, initially fled the fire — until he got close to a developed area. Given the choice between fire and people, the lion retreated back into the burning area. “That’s where his movements stopped,” Blakey says. The park service later found P-64’s remains. He’d burned his paws, and it’s possible that he was unable to hunt and starved to death.

Using data from the nine lions that survived the fire and others collared after, the scientists showed that the cats generally avoided the severely burned areas of their territories. With vegetation gone, the cats had little cover for stalking and ambushing prey.

Instead, the cougars stuck to unburned areas, and continued to avoid people. But they took more risks around human infrastructure, increasing their road crossings from an average of about three times per month to five.

A mountain lion seen running across a paved road, away from the camera
After the Woolsey Fire in 2018, mountain lions in the Santa Monica Mountains crossed roads more often, a risky move that could put the cats’ lives in danger.National Park Service

These weren’t all two-lane country highways. The first collared lion to successfully cross Interstate 405, which has 10 lanes in places, did it after the Woolsey Fire. And the big cats crossed U.S. Route 101 once every four months, whereas before the fire, they’d crossed only once every two years. Their territories also overlapped more often, increasing the potential for deadly encounters between the solitary cats. And the generally nocturnal animals increased activity during daytime hours from 10 percent to 16 percent of their active time — boosting a lion’s chances of potentially bump into a human.

Road crossing is what Blakey calls a “risk mismatch.” Lions in areas with lots of people appear to weigh the risk of encountering humans as more dangerous. But “running across a freeway is a lot more likely to be fatal,” she says. That risk, combined with the risk of running into other cats, can be deadly. One young, collared male ended up dead on a freeway in the months after the fire. He was fleeing a fight with an older, uncollared male.   

Intense burns like the Woolsey Fire highlight the resilience of mountain lions, says Winston Vickers, a wildlife research veterinarian at the University of California, Davis who was not involved in the study. “They have amazing mobility, they mostly can get away from the immediate fire, they mostly survive,” he notes. The changes in risk-taking, he says, could reflect how confined the population is, hemmed into the mountains by human development.

Wildlife crossings, such as the new Wallis Annenberg Wildlife Crossing over the 101, will hopefully give the mountain lions a safer option for roaming, though the main goal is to promote gene flow between lion populations, Blakey says (SN: 5/31/16). In a landscape where fire, humans and highways combine, it’s good to have somewhere to run.  

Animals

Here Are 3 People-Animal Collaborations Besides Dolphins And Brazilians

Published

on

By

here-are-3-people-animal-collaborations-besides-dolphins-and-brazilians

We’ve all heard that dogs are a man’s best friend, but our canine companions don’t make up the entirety of humankind’s friend circle. Humans have cooperated with wild animals throughout our evolutionary history, forming reciprocally beneficial relationships known to biologists as mutualisms.

One particularly piscine partnership that made headlines recently can be found in Brazil, where fishers catch nets full of fish with the aid of the local bottlenosed dolphin (Tursiops truncatus gephyreus).

This team-up started over a century ago, probably when fishers first noticed that the presence of dolphins was a clue that fish were hiding in the murky water, says Mauricio Cantor, a behavioral ecologist at Oregon State University’s Marine Mammal Institute in Newport.

“The dolphins are really good at detecting fish and herding them toward the coast,” he says, “and the fishers are really good at trapping the fish with their net.” Once the fish are mostly secured in the net, the dolphins are sure to snag a few for themselves.

In a study published January 30 in the Proceedings of the National Academy of Sciences, Cantor and colleagues used long-term data to show that the dolphins and fishers respond to cues from the other, and without experienced partners who know the right dance steps, the routine falls apart. “This is a really remarkable and impressive study,” says Pat Shipman, an anthropologist at Penn State University who was not involved with the research.

This fishing partnership is an important part of the cultural identity of both the fishers and the dolphins, but Cantor and his colleagues’ work shows that the practice is in decline. And among human-animal partnerships, it’s not alone. “Most of the historical cases are declining or already gone,” Cantor says. 

Given their rarity and charm, let’s take a look at some of the other known examples of human-animal cooperation.

People used to team up with orcas to hunt whales in southeastern Australia

The bottlenosed isn’t the only dolphin that humans have formed beneficial arrangements with. In the 1800s, several hunters began working with a pod of orcas (Orcinus orca) to catch large whales. At Twofold Bay in southeastern Australia, some orcas would find and harass a whale to tire it out, while others swam to alert whaling crews (made up of Aboriginal Australians and Scottish immigrants) that they’d found prey.

Once the whalers arrived and harpooned the whale, they let the orcas eat the tongue — a delicacy in the killer whale culinary world — before taking the rest for themselves.

While the dolphins and fishers in Brazil were chasing the same prey — schools of migratory mullet (Mugil liza) — the orcas and whalers were mostly after different things. The key similarity, Cantor says, is that there’s enough prey for everyone, so that no competition arises to spoil the partnership.

This relationship ultimately ended when some settlers killed two orcas, which drove the cooperative pod away from the bay, seemingly never to hunt with humans again.

These birds guide people to honey in Africa

Sometimes, a name says it all. Such is the case for the greater honeyguide (Indicator indicator), which has been labeled in both English and Latin based on its most famous trait. These birds live in sub-Saharan Africa, and cooperate with local honey hunters to gain access to succulent beeswax (SN: 7/21/16).

Birds, like humans, don’t like to be stung by bees, so a honeyguide that’s hankering for beeswax will chirp at a person to signal that they should follow. The honeyguide then leads the hunters to a bee nest and lets them do the dirty work of harvesting it.

A greater honeyguide, a small bird with a tan body, dark brown wings and head, and a red beak, looks to the right
In search of beeswax, the greater honeyguide (Indicator indicator) helps humans in Africa locate bee nests full of honey.Michael Heyns/Wikimedia Commons (CC BY-SA 4.0)

Like with orcas, honeyguides and humans are after different parts of the prize: Humans want the honey, while the birds want the wax. Honeyguides are so helpful for finding bee nests that the Borana people of East Africa blow a special whistle called a “fuulido to summon them when it’s time for a honey hunt.

Similar to the dolphins in Brazil, the relationship with honeyguides is an important part of many African cultures. Legend even has it that a scorned honeyguide, if denied beeswax on prior hunts, will lead the hunters not to delicious honey but instead into the jaws of a dangerous predator, like a lion.

Wolves and people were once on the same side when hunting big game

To see the most extreme outcome of human-animal partnership, take a look at 39 percent of the country’s beds, couches and backyards. That’s about how many households in the United States own a dog. But it turns out a canine doesn’t have to be domesticated to get along with humans; Indigenous stories from peoples in North America describe cooperating with gray wolves (Canis lupus) to hunt big game like elk and mammoths.

The wolves would run down the prey until it tired, and humans would make the kill once they caught up. Because these prey items were so massive (like the large schools of mullet), it didn’t matter that humans and wolves were after the same thing — there was plenty to go around.

Though this furry friendship doesn’t exist anymore, wolves are still important in many Indigenous cultures. Some even still continue the practice of leaving some meat for the wolves after a hunt.

Though human-animal partnerships are rare and on the decline, they “give us an illustration of how positive our human interactions can be with nature,” Cantor says.

For Shipman, the urge to engage with other animals is a defining trait of humanity. “It’s in some ways as fundamental to humans,” she says, “as being bipedal.”

Continue Reading

Animals

A Newfound Silent Frog May Communicate Via Touch

Published

on

By

a-newfound-silent-frog-may-communicate-via-touch

A newfound species of frog doesn’t ribbit. In fact, it doesn’t make any sound at all.

Many frogs have unusual characteristics, from turning translucent to being clumsy jumpers (SN: 12/22/22; 6/15/22). The recently discovered amphibian lacks a voice. It joins a group of seven other voiceless frog species called spiny-throated reed frogs that reside in East Africa.

Instead of croaking, the spines on male frogs’ throats might help their female counterparts recognize potential mates via touch, sort of like braille, says conservation biologist Lucinda Lawson of the University of Cincinnati.

Lawson and colleagues spotted the little frog, only about 25 millimeters long, in 2019 while surveying wildlife in Tanzania’s Ukaguru Mountains. The team immediately recognized the animal, now named Hyperolius ukaguruensis, as a spiny-throated reed frog. But something seemed off.

“It [was] the wrong color,” Lawson says. Most frogs from this group are green and silver, but this one was gold and brown. Some quick measurements to check if the peculiar frog simply had trivial color variations or if it could be a new species revealed that its eyes were smaller than other spiny-throated reed frogs. The researchers agreed: “Let’s do some genetics,” Lawson says.

They ran DNA tests on two frogs that looked like they belonged to the suspected new species, as well as 10 individuals belonging to known spiny-throated species. Comparing the golden frogs’ genetic makeup with that of the others revealed the oddballs were genetically distinct, Lawson and colleagues report February 2 in PLOS ONE.

a Hyperolius ukaguruensis stands on a leaf. It is golden-colored with darker splotches along its back
The golden-hued Hyperolius ukaguruensis stands out from its fellow spiny-throated reed frogs, which also lack a voice but are typically green.Christoph Liedtke

Each frog species in this voiceless group — including H. ukaguruensis — lives in its own isolated domain of forest. All seven of the previously known species are endangered or vulnerable. This seclusion makes it vital to distinguish species and get them added to the conservation priority list, Lawson says. Then, governments and organizations can begin protecting the region that the new, potentially endangered animal calls home.

Continue Reading

Animals

Are Your Cats Having Fun Or Fighting? Here Are Some Ways To Tell

Published

on

By

are-your-cats-having-fun-or-fighting?-here-are-some-ways-to-tell

Are your cats play fighting or fighting fur real?

It turns out that certain behaviors in domestic cats could be telltale signs that an interaction is friendly, aggressive or something in between, researchers report January 26 in Scientific Reports.

“It is a question we hear a lot from cat owners,” says cat behavior expert Mikel Delgado of Feline Minds, a cat behavior consulting company in Sacramento, Calif., who was not involved in the study. “So I was excited to see that researchers are taking on this topic.”

Scientists have studied cats’ social relationships — both with other cats and humans — but it can be tricky to tell whether two cats are playing or fighting, says veterinarian and cat behavior researcher Noema Gajdoš-Kmecová of the University of Veterinary Medicine and Pharmacy in Košice, Slovakia (SN: 9/23/19).

Sometimes cat owners miss the signs of a tense relationship because they think their pets are just playing, which can lead to stress and illness in the animals, she says. Other times, owners rehome their cats after incorrectly assuming their pets are fighting.

To assess and categorize interactions, Gajdoš-Kmecová and colleagues watched about 100 videos of different cats interacting in pairs. After viewing around one-third of the videos, Gajdoš-Kmecová identified six types of behaviors, including wrestling and staying still. She then watched all of the videos and noted how often each cat exhibited one of the specified behaviors, and for how long. By running statistical analyses on the behaviors, she pinpointed three types of interactions between the cat pairs: playful, aggressive and intermediate.

To confirm the outcome, other members of the team also watched the videos and classified each interaction between felines.

Some clear connections emerged. Quietly wrestling, for instance, suggested playtime, whereas chasing and vocalizations, like growling, hissing or gurgling, implied aggressive encounters.

Intermediate interactions had elements of both playful and aggressive encounters, but especially included prolonged activity of one cat toward the other, such as pouncing on or grooming its fellow feline. These in-between encounters could hint that one cat wants to keep playing while the other doesn’t, with the more playful cat gently nudging to see if its partner wants to continue, the authors say.

This work provides initial insights into cat interactions, Gajdoš-Kmecová says, but it’s just the start. In the future, she plans to study more subtle behaviors, like ear twitches and tail swishes. Both Gajdoš-Kmecová and Delgado also stress that one contentious encounter doesn’t necessarily signal a cat-astrophic relationship.

“This is not just about one interaction,” Gajdoš-Kmecová says. Owners “really should look into the different, multiple interactions in multiple periods of life of the cats and then put it into context.”

Continue Reading

Trending