The effectiveness of US mitigation and monitoring practices for the threatened Valley elderberry longhorn beetle

Habitat mitigation frequently leads to planting of new habitat, assuming that it can replace lost natural habitat. Yet this practice has rarely been examined in detail. In the USA habitat mitigation is frequently allowed under the US Endangered Species Act, providing monitoring reports which represent a potentially valuable data source for imperiled species. We used publicly available reports for the US threatened Valley elderberry longhorn beetle (Desmocerus californicus dimorphus) to assess record keeping practices used by US Fish and Wildlife Service (FWS), and the utility of such analyses for improving conservation. A large portion of mitigation reports known to exist were missing from FWS files, indicating problems with data management, and a loss of important information. Transplanted brought mature beetle host plants and beetles to sites, promoting beetle colonization. Conversely, few sites with seedlings were colonized. Results indicate a need for improved data management by FWS and longer term monitoring.