News of the Wild

Movements of mountain lions, bird feeding impacts and amazing, expanding trunks

Mark Wexler
Animals
Feb 04, 2022

Pandemic alters mountain lion behavior

During the spring of 2020, when most Californians were quarantined at home by the pandemic, how were the state’s mountain lions (above, with radio collar) responding? To find out, ecologists from the University of Nebraska–Lincoln (UNL) and National Park Service tracked the movements of 12 of the cats in the greater Los Angeles area for 43 days. By comparing the results with seasonal movement data gathered prior to 2020, the scientists found that, rather than expanding their ranges in the absence of people, the big cats actually occupied smaller territories than they had before COVID-19. The researchers, who reported their findings in the journal Ecological Solutions and Evidence, also discovered that the felines generally traveled shorter distances, in some cases half as far, than they had in previous years. “It makes sense that when you don’t have to dodge as many humans, you could use the landscape more efficiently,” says UNL vertebrate ecology professor and lead author John Benson. In addition to issuing a statewide stay-at-home order during the early months of the pandemic, California closed several Los Angeles parks containing habitat favored by the cats.

Black capped chickadee (Poecile atricapillus) on bird feeder

Impacts of bird feeding

Scientists at Oregon State University (OSU) have reassuring news for the millions of U.S. households that feed songbirds during the cold months. “There’s still much we don’t know about how intentional feeding might induce changes in wild bird populations, but our work suggests that putting out food for small birds in winter will not lead to an increased dependence on human-provided food,” says OSU animal ecologist Jim Rivers. To investigate the question, Rivers and his colleagues outfitted 67 black-capped chickadees (above) with radio-frequency identification tags and studied the birds’ feeder habits under different experimental conditions in the wild. The scientists chose chickadees because they frequent feeders during winter and have high daily energy requirements. The birds also typically take just a single seed per feeder visit, enabling the researchers to get accurate measures of feeding activity. In the Journal of Avian Biology, they write: “It’s clear that the chickadees in our study did not increase their visitation rates nor did they increase their reliance on supplemental feed during a period when they might have benefited from it the most.”

An elephant drinking water in Botswana

Amazing, expanding trunks

Each day, an African elephant (above) consumes 400 pounds of food and guzzles several gallons of water—but until now, scientists weren’t sure how the animal manipulates its trunk to satisfy such an enormous appetite. In a recent study of captive elephants published in the Journal of The Royal Society Interface, engineers at the Georgia Institute of Technology discovered that the pachyderms dilate their nostrils to reduce the thickness of their trunks’ walls, thereby increasing the space inside by some 60 percent. “It turns out their trunks act like suitcases, capable of expanding when necessary,” says lead author Andrew Schulz.

Using high-speed video and computer modeling, the scientists determined that the elephants could suction air at a rate of nearly 500 feet per second, enabling them to inhale more than 1 gallon of water in 1.5 seconds. This suction power, they explain, stems from the animal’s specialized respiratory system, which produces unusually high lung pressure to generate air-velocity levels unmatched by any other terrestrial species. The researchers say that elephants also are the only animals capable of using suction both on land and under water.