October 23, 2018
Kim Delfino

Did you know that one out of every three bites of food is dependent on pollinators? Or that more than 80% of all terrestrial plant species require an animal pollinator (usually an insect) to reproduce? We need pollinators keep our state and our country blooming and our economy thriving.

One of our most recognizable and well-loved pollinators is the bumble bee. Usually yellow, black, and fuzzy, wild bumble bees are found throughout the state. However, all is not well for these industrious wild bees. Habitat loss, disease, and pesticides threaten to decimate our pollinators if we don’t affirmatively act to save them. In 2015, a study published in the Proceedings of the National Academy of Sciences found that wild bee abundance declined in 23% of the contiguous U.S. from 2008–2013. Here in California, recent studies have revealed that several bumble bee species in California are imperiled and in need of immediate conservation attention.

As part of our efforts to protect our important pollinators, on October 16, Defenders of Wildlife along with the Xerces Society and the Center for Food Safety, filed a petition with the California Fish and Game Commission to list four species of native bumble bees — western bumble bee, Franklin’s bumble bee, Crotch’s bumble bee, and the Suckley cuckoo bumble bee — as Endangered under California’s Endangered Species Act. Defenders and our partners took this step to save these four pollinator species from going extinct because all four of these native bee species are in steep decline and are found in only a few areas within their historic range.

Current regulations have proven insufficient to reverse the sharp decline in populations and protection under our state endangered species act is the last line of defense if we hope to keep these four bee species from going extinct.

The diversity and strength of bee populations is critical to maintaining a healthy and robust food supply in California and beyond. About one-third of food production depends on pollinators, and 75% of all fruits and vegetables produce higher yields when visited by pollinators. Native pollinators, including bumble bees, provide ecosystem services estimated at more than nine billion dollars annually in the U.S. Bees are essential to the reproduction of many of California’s specialty crops, including tomatoes, peppers, melon, squash, cotton, and almonds, as well as to native ecosystems — from the flower fields of the Carrizo Plain to the montane meadows of the Sierra Nevada.

By acting on this petition, California has an opportunity to demonstrate how an individual state can lead the nation in protecting a diverse suite of pollinators for the future.

More information on the four native bee species in the petition:

The Crotch bumble bee (Bombus crotchii) was historically common in the southern two-thirds of California, but now appears to be absent from most of it, especially in the center of its historic range (Hatfield et al. 2014; Richardson et al. 2014); analyses suggests sharp declines in both relative abundance (98% decline) and persistence (80% decline) over the last ten years.

Franklin’s bumble bee (Bombus franklini) is in imminent danger of extinction and notably has the most limited geographic distribution of any bumble bee in North America and possibly the world (Williams 1998). Extensive surveys since 1998 have demonstrated that there has been a precipitous decline in the number of individuals and localities in the past several decades; this species has not been seen in California since 1998 and has not been seen anywhere since 2006.

The western bumble bee (Bombus occidentalis occidentalis) has recently undergone a dramatic decline in abundance and distribution and is no longer present across much of its historic range. Declines suggest it has been lost from 53% of its historic range and has experienced an 84% decline in relative abundance (Hatfield et al., unpublished data); in California, B. o. occidentalis populations are currently largely restricted to high elevation sites in the Sierra Nevada (Xerces Society 2012).

The Suckley cuckoo bumble bee (Bombus suckleyi), relies upon western bumble bees to complete its life cycle, and thus is uniquely susceptible to extinction (Suhonen et al. 2015). It is considered Critically Endangered by the IUCN and its range has declined by 58%.


Kim Delfino

Kim Delfino

California Program Director
Kim Delfino oversees the work of Defenders’ six-person California program team in protecting and restoring California’s imperiled wildlife and the places in which they live.

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