On Jan. 12, the U.S. Fish and Wildlife Service announced that it will evaluate three rare insects for protection under the Endangered Species Act: the Great Basin silverspot butterfly, narrow-foot diving beetle and Scott riffle beetle. This decision results from three petitions submitted by WildEarth Guardians in 2013. Fish and Wildlife now has 12 months to study the species and decide whether to propose protections as “threatened” or “endangered” for each imperiled insect.
“The declines of these small insects are caused by serious threats like disappearing aquifers and streams. Those problems need to be addressed for the sake of plants, animals and people,” said Taylor Jones, endangered species advocate for WildEarth Guardians. “The smallest animals often give us the biggest warning signs of nature in crisis, and the Service should act quickly to address the causes of these insects’ declines.”
The Great Basin silverspot butterfly (Speyeria nokomis nokomis) is a large orange-brown butterfly with black markings which inhabits wet meadows, seepage areas, and marshes in otherwise desert habitats of the Southwest. A 2000 and 2006 study reported the butterfly’s presence in La Plata County. Montezuma County is listed in the study as historical range, with no reported sightings, Taylor said. The butterfly depends on the bog violet (Viola nephrophylla), the only plant its larvae will eat. In the U.S., they are found in Arizona, Colorado, New Mexico, and Utah, but have disappeared from many of their former sites. Habitat loss and fragmentation is the greatest threat to silverspots, along with insecticides and climate change. In the last 150 years, the Great Basin completely lost more than half of its wetlands.
The Global Heritage Status Rank for the Great Basin silverspot butterfly subspecies is critically imperiled (G3T1), based on its “limited range, few remaining sites, and significant threats to habitats.”
