Nepal-born ecologist Susma Giri studies how temperature affects declining pollinator populations in the age of climate change.
Susma Giri collects insect samples from bee cups around String Lake in the Grand Tetons. The cups contain soapy water, and the scent of the soap attracts bees that are visiting nearby flowers. The cups were set out in the field for 48 hours.
Susma Giri searches for bees on Rendezvous Peak in Grand Teton National Park, Wyoming.
Clutching a glass vial, Susma Giri walked slowly and patiently through a field of waist-high wildflowers in Grand Teton National Park. Craggy ridgelines and a broad green valley sprawled out below with few signs of civilization. Giri, an ecologist then working on her Ph.D. at the University of Wyoming, stooped down and carefully enclosed a flower with her vial, waited, then pulled away and screwed on the cap. Inside, a tiny bee buzzed about.
After euthanizing it quickly with cyanide, Giri then weighed the insect and pressed on its abdomen so it vomited the nectar inside its crop. She measured the amount and sugar concentration of the nectar, cleaned the pollen balls off the little bee’s legs, and carefully placed its body in an icebox to take to the lab for further analysis.
Bees perform the crucial service of pollination in both wild and cultivated landscapes, but colony collapse disorder and the decline of wild bee populations have called attention to their welfare in recent years. Giri, 28, is interested in the effects of temperature on bees: How do temperatures affect their physiology and ability to function? And do warmer temperatures lead to greater infestations of parasites and pathogens? Her hope is that the work will shed light on the effects of climate change on these important insects.
“I have always wanted to study the effects of temperature in organisms,” says Giri, a National Geographic Young Explorer who studied the Himalayan serow, an endangered ungulate, for her undergraduate degree at Tribhuvan University in her native Nepal. “If you’re able to know the effects of temperature and how organisms are able to cope, you’ll be better able to predict what might happen to the them in the future.”
Grand Teton National Park is a prime place to study the effects of temperature on wildlife. It not only protects large swaths of undisturbed land—spiky peaks, high alpine meadows, and conifer forests—but also features striking changes in altitude without much change in latitude. But its rugged nature also makes it a challenging place to work.
Giri has never been stung by a bee she’s collected in the wild. (She was once stung five times by a worker bee in the lab.) But she does have to worry about other critters in Grand Teton: bears. On several occasions, she has encountered black and grizzly bears on hiking trails threading remote areas of the park. One time, she sat in her car after a field trip as a grizzly bear peered into the windshield looking for food.
But her efforts have yielded intriguing preliminary results. She found, for example, that bees living at altitude, in colder temperatures, tended to have a lower incidence of parasites than those living at lower altitudes with warmer temperatures and more human development. More study is needed to tease out these relationships.
After finishing her Ph.D. in June, Giri took her research back to Nepal. With her chemist husband and 12 other researchers, she founded the Kathmandu Institute of Applied Sciences, which supports researchers from fields ranging from atmospheric science to ecology. The institute is applying for grants, organizing a citizen-science project measuring the rainfall in various areas of Nepal, and, Giri hopes, will soon embark on another project close to her heart: finding and recording rarely studied bee species in Nepal, reports national- geographic.