Bum­ble­bees:

UT re­searcher’s work ex­am­ines ways to fos­ter pol­li­na­tion.

Austin American-Statesman - - FRONT PAGE - 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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