Austin American-Statesman

Bumblebees:

UT researcher’s work examines ways to foster pollinatio­n.

- By Asher Price asherprice@statesman.com

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.

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