In an article published in July 2012, in the Journal of Environmental Economics and Management, Christian Langpap and Joe Kerkvliet of Oregon State University assess the effectiveness of habitat conservation plans.  The abstract reads:

Habitat conservation plans (HCPs) have become a key instrument for implementation of the Endangered Species Act (ESA) on private land. However, there is no systematic analysis of their effectiveness in promoting endangered species recovery. This paper is the first to provide a comprehensive analysis of the impact of HCPs on species recovery status. We find evidence that HCPs have a significant positive impact on species recovery. Our results also suggest that the recovery benefits are larger when species have relatively larger plans. However, we fail to find strong evidence that multi-species plans covering more species are more effective than plans which include fewer species.

The article is available for purchase here.  The authors use data on the recovery status of species set forth by the Fish and Wildlife Service in reports to Congress, together with listed species characteristics, and data regarding HCPs also generated by the Fish and Wildlife Service.  They analyze the data using standard statistical tools.  The authors urge the federal wildlife agencies to encourage non-Federal parties to develop HCPs, including by reducing the burden on applicants and stream-lining the permitting process.