Environment

Endangered frogs find shelter under BPA transmission lines

While it is a bit smaller than many of its amphibian cousins, the Oregon spotted frog, at first glance, looks a lot like a frog you might see hopping across your back yard.

But a better place to find this frog, listed as threatened under the Endangered Species Act, might be under the Bonneville Power Administration's high-power transmission lines in the Pacific Northwest.

There, the wet habitat is just cushy for the Oregon, the most aquatic native frog in the region. BPA is doing its part to enhance the habitat to accommodate as many of the frogs as possible, saving them from possible extinction.

Jonnel Deacon, a BPA physical scientist, said the Oregon's natural habitat once extended from British Columbia to California. "Since then, due to a variety of things, housing, construction, invasive species, their habitat has really shrunk. One of the places they have found refuge is under our lines."

They are not little lines either. According to BPA spokesman David Wilson, the frog has found a home living beneath transmission lines ranging from 230 kV to 500 kV, some of the largest in the region.

It is hard to say exactly when the Oregon decided to take up housekeeping under the lines. "Under our lines we have known about them since they were recently listed under the Endangered Species Act," Deacon said. "We went on site with Fish and Wildlife to do a more complete survey of the area. That was in 2018."

Deacon said there is no way of knowing for sure at present how many Oregons are living under the lines. The adult frogs are hard to find. More often, researchers encounter egg masses which are a good indication that the frog is comfortable enough under the lines to deposit eggs that could produce dozens, if not hundreds or thousands, of offspring.

In fact, Deacon said he and his colleagues have actually seen only two adult frogs. "They are confirmed under lines in two distinct locations in Washington, near Olympia, and near the Samish River."

The US Fish and Wildlife Service is happy to work hand in glove with BPA to enhance the habitat for the frogs and other little creatures and plant species around the transmission lines. Deacon said the Oregon is fond of eating decaying plant material, among other things. It does not, however, "go after other frogs," Deacon said.

Going forward, Fish and Wildlife and BPA have a recovery plan for the frogs. "BPA has in place a biological opinion with Fish and Wildlife that includes conservation measures for activities that are meant to limit BPA negative impacts to that species," Deacon said. For example, BPA is allowed to use only small amounts of herbicide in specific locations for vegetation control.

Along with the Oregon, other species of frogs and salamanders also are benefiting from the refuge improvements.

"Frogs prefer a wet area. They don't like to spend a lot of time outside water," Deacon said.

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