On September 17, 2014, the U.S. Fish and Wildlife Service (Service) withdrew (pdf) its proposal (pdf) to remove the valley elderberry longhorn beetle (Desmocerus californicus dimorphus) from the Federal List of Threatened and Endangered Species. While this means the beetle will continue to be protected as a threatened species under the Endangered Species Act (ESA), the Service did reduce the area in which the species is presumed to occur.
The beetle was listed as threatened and critical habitat designated, in 1980 (pdf). Until recently, the beetle’s range was believed to include much of the San Joaquin and Sacramento Valleys, from Shasta County in the northern Sacramento Valley to Kern County in the southern San Joaquin Valley, California; but occurrences were thought to be rare. In its 2006 Five-Year Review (pdf), the Service recommended delisting the beetle, generally because the beetle was determined to be more abundant and widespread than documented at the time of listing.
In 2010, the Service received a petition to delist the beetle. In 2012, the Service published a proposal to delist the beetle in which the Service recommended eliminating ESA protections for the beetle based on increased beetle populations and ongoing protections afforded to the species’ riparian habitat.
The Service’s 2014 withdrawal of the delisting proposal documents a reduction in the beetle’s distribution based on public comment and scientific peer review. The Service describes its current estimates as, “the most accurate assessment of the presumed extant occurrences of the valley elderberry longhorn beetle.”
According to the Service’s September 16 news release (pdf) announcing the withdrawal of the proposed delisting, the species’ range will no longer include Kern, Kings and Tulare counties. And as such, “the regulatory protections of the ESA [afforded to the beetle] will now be applied to a smaller area.” However, neither the notice nor the news release makes clear how the Service’s act of redefining the species’ range will affect the Section 9 prohibition against “take” of the beetle if it is found outside of the defined range.
The beetle’s reduced range, combined with threats from invasive plants, pesticides, and global climate change, are identified as the principal reasons for the beetle’s continued listing as a threatened species.