“Kestrels in California have been on a long downward trend since 1950 at least,” says GGRO Director Allen Fish, citing several potential reasons for the decline, including predation by other raptors. Pesticides destroy important food sources for kestrels and also sometimes poison the birds themselves. Rodenticides and insecticides work their way up the food chain and cause secondary poisoning, as do heavy metals like selenium, mercury, and lead. Loss of nesting sites is another problem: kestrels are cavity nesters and rely on old woodpecker holes and tree hollows; they do not excavate their own cavities. Very old trees are becoming harder to find in managed forests, says Fish, and dying trees with potential nesting cavities are often treated as fire tinder and removed for safety or aesthetic reasons. The Kestrel Campaign, a Bay Area volunteer group funded by Save Mount Diablo, hopes to help local kestrel populations recover by educating the public about issues like rodenticides, and installing kestrel nesting boxes on public and private land near Mount Diablo. The group installed 24 boxes last year and Brian Richardson, the team’s leader, says there has been nesting activity in some of them. “Such citizen science operations, along with focused removal of poisons from our environments, together have a great chance of tipping the scales back in favor of this charismatic and useful falcon,” says Fish.