What helps mammals survive natural disasters? | Science

When Cyclone Idai struck Mozambique’s Gorongosa National Park in May 2019, the park administered in 2008 – one of the most technologically advanced safari parks in its management – ​​was facing one of the deadliest natural disasters. One, leading to the death of a large number of wild animals. in this park.

Thanks to the park’s surveillance cameras and animal tracking equipment linked to GPS, an international team led by researchers at Princeton University in the US was able to track and study the responses of animals living in the park. Park, moment by moment. The team presented its findings in a paper recently published in the journal Nature.

Real-time mammalian behavior

The paper focuses specifically on tracking mammalian behavior. As the researchers said in a Phys.org press release, “This is the first study ever to track the real-time response of a large mammal community to a natural disaster.”

Haley Brown, a postdoctoral fellow in the Department of Ecology, said the researchers looked at rising water levels and animal responses in the hours, days and weeks after the hurricane, and how some of those animals survived the floods. Others did not survive. Professor of Environmental Biology at Princeton University and first author of the paper.

Researchers used data obtained before, during and after the storm to create not only a description of the event but also a broader forecast so that park managers can “better predict the impacts of increasingly severe weather events.” .

Size…the best indicator of survival

The team found that the best predictor of survival was size, as the number of lesser oribis (a greyhound-sized antelope) declined by 50 percent, while about half of the reedworms (a larger African antelope) , the average-sized antelope also died, and its number decreased by only 4%.

GPS data shows the antelopes are looking for hills to climb, including termite mounds up to 5 meters high and 20 meters long that have become islands in the floods.

Researchers discovered that a surviving member of the antelope was jumping from mountain to mountain, quickly crossing mountain floods before finding safety in the forest at higher altitudes. The four largest herbivores: bushbuck, kudu, sable and elephant did not die.

The researchers found that body size also provided protection in a secondary way, as smaller animals were not only unable to cross water but also were unable to overcome dietary restrictions later on. Because floods last so long and kill many low grasses and plants, small animals cannot tolerate these periods of limited nutrition, while larger animals need to rely on more fat.

Brown said the few carnivores in the park weathered the storm well, with wild dogs and leopards taking advantage of the concentration of prey at high altitudes, while lions, whose main food source is pigs, stayed at high altitudes months, but they’re basically stuck at high altitude. Not affected by the hurricane.

As a result, the researchers have two key recommendations for wildlife managers: evacuate the smallest and most ecologically vulnerable creatures to safer areas before a storm and provide supplemental feeding after a storm.