UT researcher’s work examines ways to foster pollination.
As global pollinator crisis continues, UT researcher examines foraging habits of bees.
To work in Shalene Jha’s University of Texas lab group, researchers must meet at least one qualification: No allergy to bee stings.
Jha’s work looks at the relationship between bees, one of the world’s great pollinators, and the urban landscape. Her research involves field sites around Austin, and she and her assistants have captured at least 5,000 of them.
A report co-authored by Jha and published this month in the journal Proceedings of the National Academies of Science proves that paved areas are much less attractive to bees.
Eighty-five percent of native bee species nest in the ground, and pavement eliminates their opportunities. Bare ground or xeriscaping, which often involves crushed granite or rocks for a drought-friendly garden, still leaves nesting options for bees, says Jha.
While Jha acknowledges that’s an unsurprising finding, it fits into a wider effort to detail how farmers and city planners ought to think about fostering pollination. A healthy, dense bee population means better crop yields, but paved areas or plantings with little diversity leave bees less likely to pollinate.
“You want bees to move around a lot,” she said.
“If you have any connection to agriculture, or you eat, or you wear cotton, this is something you should care about,” she said. Exacerbating matters: A global, unsolved die-off of bees that Jha says “is as dire as ever.”
Recognizing the value of pollinators, the federal government has offered incentives to farmers that include habitats for beneficial insects. Gov. Rick Perry signed a proclamation in mid-June to mark National Pollinator Week.
Roughly one third of our food chain is the result of pollination that happened in a farmer’s field, Michael Warriner, an invertebrate biologist with the Texas Parks and Wildlife Department, reported at the time. During a single day, a female bee may visit several hundred flowers, depositing pollen along the way.
Jha’s research suggests reducing pavement and adding more flowering patches, such as gardens and diversified farms, would provide avenues for bee nesting, foraging and pollination.
Jha, who grew up in Mich-
igan, has long been fascinated by the relationship between agriculture and insects. Her grandparents tended mango orchards in India, which she visited as a child. As an undergraduate at Rice University, she read “The Forgotten Pollinator,” a book that she describes as the “Silent Spring” — a 1962 book cited as helping to launch the environmental movement — of the pollinator crisis.
She joined the University of Texas faculty a year-and-a-half ago, after completing her research at the University of California at Berkeley.
Austin has about 180 species of bees, she said. They can be distinguished, in part, by the location of their hair, which catches pollen. Some have hair on their eyes, some on their knees and others on their bellies. Researchers also distinguish bees, which they capture with butterfly nets, by the number of teeth they have and patterns on their shoulders.
Once researchers capture valuable queen bees — distinctive for their larger size and lower buzzing sound — they snip off a bit of bee toe for lab examination before releasing her.
In bee research parlance, the snipper is called “a bee squeezer”; it resembles moustachetrimming scissors. The toe does not grow back, but studies have shown no difference in survivorship among the bees, which have six legs, Jha said.
Scrutinizing the toe snip, researchers then examine the bee’s DNA — each bumble bee colony is a massive sisterhood — and map foraging patterns.
In “destructive captures,” worker bees are euthanized using acetone, an active ingredient in nail polish remover. Researchers can learn more about the bees’ predilections and examine the bees’ guts for signs of disease — one of the chief suspects in the pollinator die-off.
“I tell them as I’m killing them that they’re not dying in vain,” Jha said.
The utility avoids pruning in neighborhoods with mainly red and live oak trees between midFebruary and June to prevent the spread of oak wilt. And from March through September the utility avoids pruning areas that provide habitats for endangered songbirds.
Still, the Austin Energy began taking a less aggressive stance toward trimming partly because of policy changes made in 2006 after residents complained of Austin Energy crews threatening to fell or trim larger trees in neighborhoods near the University of Texas.
Austin Energy offers replacement trees when it determines existing trees must be removed. The utility says it replaces about 1,000 trees a year and provides funding to plant another 5,000 trees through community-wide programs.