Mesh fence studied to protect Walla Walla bees
KENNEWICK, Wash. — Washington State University will be testing a mesh barrier in Walla Walla County this June in hopes of reducing the number of valuable bees being killed by highway traffic.
Native alkali bees leave their underground nests to pollinate alfalfa near the towns of Lowden and Touchet. The barriers will be on farmer Mike Buckley’s property, installed on each side of a road and in the median of the mock highway.
Doug Walsh, WSU professor of entomology, said he believes the mesh barrier system will be another failure as he continues to look for ways to protect the bees along the proposed reroute of Highway 12 between Nine Mile Hill and Woodward Canyon.
“(The bees) hug the ground so they don’t get blown off course,” said Walsh, who began the study about two years ago.
Despite being pessimistic, Walsh said he will test the idea again this year to make sure. What he and graduate student Amber Vinchesi have noticed so far is that the bees tend to fly near the ground when the wind blows faster than 5 miles per hour.
The state Department of Transportation plans to move Highway 12 about a half mile north of the current highway near Lowden and Touchet because there’s no room to widen the highway in either town, officials said.
The project to create four lanes will make for safer travel between the Tri-Cities and Walla Walla, and the section is one of several left in the project to improve the Highway 12 between Highway 124 and Walla Walla.
However, moving the highway puts alfalfa farm fields and alkali bee beds in the highway’s path, which concerns farmers.
It began as a contentious issue because farmers believed the impact to their farms was not considered, but Jason Smith, WSDOT South Central region environmental manager, said his agency is committed to working with farmers. The goal is to create a safer, more efficient highway while minimizing the impact to alfalfa seed farmers.
That’s why WSDOT has partnered with WSU to better understand the issue and find solutions, Smith said. And the work Walsh is doing will help keep state officials from proposing ineffective mitigation methods, Smith said.
There is time to find a solution because there is no funding and no timeline to build the section of Highway 12, Smith said.
Walsh’s $232,000 study, funded by WSDOT, will continue for two more years.
In Walla Walla County, about 16 farmers have 12,000 acres of alfalfa seed growing near Touchet and Lowden, and they have contracts with a handful of seed companies, said Buckley, a second-generation farmer with about 2,600 acres of alfalfa grown for seed.
Contracts for the perennial crop typically last for three years, and then the seed companies want farmers to plant a new variety, said Buckley, who has farmed alfalfa seed for 30 years.
Buckley said his bee beds take up about three acres. Bees in one acre of bee bed can pollinate about 200 acres of alfalfa, and the area’s farmers nurture between 30 to 40 bee beds, he said.
Growers manage alkali bees by creating artificial dry creek beds, Walsh said. They’ve used subsurface irrigation, with pipes two feet underground, to create acres of the beds and have added salt to the surface.
It takes years to make an artificial bee bed in the sandy soil, said Buckley, who has some beds are about a decade old.
The Walla Walla County farmers have been able to maintain use of bee beds, while in other areas, pesticides in nearby fields have poisoned the bees, Walsh said.
“It’s a big competitive advantage to other alfalfa seed growing areas in the world,” he said.
Farmers from other areas have to import the leaf cutter bee from Canada, and the price for those bees has skyrocketed in the past couple years, Walsh said.
In the past eight years, the local alkali bee population has grown, Buckley said. That’s meant area farmers have imported fewer leaf cutter bees to pollinate the alfalfa.
“The alkali bee is our No. 1 choice,” Buckley said.
That’s because the alkali bee is a better pollinator, he said. They fly about one mile instead of several hundred feet like leaf cutter bees, and so it takes fewer of them to pollinate the same area.
Honey bees have figured out how to get nectar from the blossom without tripping it, so they don’t pollinate alfalfa, Walsh said. When an alkali bee trips the blossom, it gets bopped on the head with pollen, which is how pollen is spread.
Each female alkali bee collects more than its body mass in pollen every day for about one month, Walsh said. The bees are slightly smaller than a honey bee.
“It’s really every female for herself,” Walsh said.
The female digs about 20 holes where she lays an egg under a pollen ball, he said. The larvae will eat the pollen and winter as a pre-pupae until emerging as an adult.
The bees pollinate alfalfa between the second week of June until the second week of July. Harvest is normally between mid-August and the first week of September, Buckley said.
Walsh said his mesh barrier project will benefit from a $1 million federal grant he recently received to study alkali bee flight patterns. The study was triggered by the deregulation of genetically engineered alfalfa seed, he said.
Walsh said he will collect seed from fields to see how the pollen is moved from one field to another.
Six or seven bee beds will be within one mile of the new Highway 12 path, Walsh said. That is about five million bees, so about one-third of the 17 million alkali bees in the area could be affected by the highway, Walsh said.
“It doesn’t mean they are all going to die,” he said.
Buckley said they already lose a small fraction of the bees to the highway, but the impact would be greater with the new route.
Options other than the mesh barriers will be considered, and those include cutting the road into the earth or relocating bee beds, Smith said.