Native bees and powerlines
Based on work I did at PWRC to develop monitoring techniques for native bees, I have become interested in the idea of making use of powerline rights-of-way as mini-nature reserves. This land, if properly managed, has the potential to provide millions of acres of suitable habitat for early successional species, thereby maintaining critical source populations. Power companies already intensively manage the land under their lines and will continue to do so into the foreseeable future. Based on conversations I've had with land managers from NSTAR, many Power companies are amenable to tailoring their management practices to maximize biodiversity under their lines, so long as the vegetation does not interfere with their ability to deliver power. Mostly, they are interested in anything that will boost their image, so why not take advantage of that?
The following is an abstract from our paper which was recently published in Biological Conservation [124 (2005) 133-148]
The potential conservation value of unmowed powerline strips for native bees
K. N. Russella,*, H. Ikerdb and S. Droegec
aDivision of Invertebrate Zoology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA
bBee Biology and Systematics Laboratory, Utah State University, 5310 Old Main Hill, Logan, UT 84322-5310
cUSGS Patuxent Wildlife Research Center, 12100 Beech Forest, Laurel, MD 20708-4083, USA
Abstract
The land area covered by powerline easements in the United States exceeds the area of almost allnational parks, including Yellowstone. In parts of Europe and the U.S., electric companies have altered their land management practices from periodic mowing to extraction of tall vegetation combined with the use of selective herbicides. To investigate whether this alternate management practice might produce higher quality habitat for native bees, we compared the bee fauna collected in un-mowed powerline corridors and in nearby mowed grassy fields at the Patuxent Wildlife Research Center (MD). Powerline sites had more spatially and numerically rare species and a richer bee community than the grassy fields, although the difference was less pronounced than we expected. Powerline sites also had more parasitic species and more cavity-nesting bees. Bee communities changed progressively through the season, but differences between the site types were persistent. The surrounding, non-grassland landscape likely has a strong influence on the bee species collected at the grassland sites, as some bees may be foraging in the grasslands but nesting elsewhere. Improving habitat for native bees will help ameliorate the loss of pollination services caused by the collapse of wild and managed honeybee populations. This study suggests that powerline strips have the potential to provide five million acres of bee-friendly habitat in the U.S. if utilities more generally adopt appropriate management practices.