July 2013

Partnership Cultivates Habitat for Endangered Species

A record breeding year has given new hope for an endangered subspecies of least tern on the shores of San Francisco Bay, thanks in large part to help from local vegetation management experts, including Dow AgroSciences and the California Department of Transportation (Caltrans).

In 2001, the East Bay Regional Park District created a least tern sanctuary at Hayward Regional Shoreline. Since then, California least tern numbers have increased gradually in the area, with 189 incubated nests recorded at the Hayward Regional Shoreline in 2012. The record 162 breeding pairs produced 228 chicks, giving resurgence to the highly endangered West Coast species.

A partnership between Caltrans and Dow AgroSciences helped curtail rapid vegetation growth on the island, which previously had restricted nesting opportunities.

“Caltrans looks at partnerships like this as an opportunity to get things done that would be difficult to accomplish otherwise,” said Bill Nantt, landscape specialist at Caltrans. “It took patience, but the results made the process well worth it.” Donations of time, technical expertise, materials and equipment helped cultivate ideal nesting conditions for the least tern.

“Thanks to the generous donation of staff time, technical expertise, materials and equipment from Caltrans and Dow AgroSciences, we are seeing a positive effect on the future of these special status birds at the Hayward Regional Shoreline,” says David Riensche, wildlife resource analyst and certified wildlife biologist with the East Bay Regional Park District. “Our island is now the second-largest least tern colony north of Ventura County, and even more astounding is that our tern sanctuary reportedly made a fledgling contribution that amounted to 20 percent of the species’ population in California last year.”

Dow AgroSciences contributed a combination of Milestone®, Capstone®, Rodeo® and Dimension® specialty herbicides to curb the overgrowth of vegetation on the Hayward Regional Shoreline. This mix of herbicides was prescribed by local pest control advisors, and has been proven to be “practically nontoxic” in laboratory testing. Least terns, and the surrounding ecosystem, were unharmed by the use of these herbicides, which were carefully applied by trained applicators to reduce excess vegetation.

By working to reduce this vegetation, Caltrans and Dow AgroSciences were able to provide an environment conducive to nesting and help boost populations of California least terns to record levels. The Hayward Regional Shoreline is now a viable nesting location for this endangered species, and wildlife experts look forward to monitoring future growth.