Sonoma County Water Wishes
Survey Finds Zero Owl Nests
by Robert Evans
Fifteen volunteer observers monitored the historic Burrowing Owl nestingareas in Sonoma County this summer, and found no breeding pairs.
Up to ten individuals had been spotted at various locations during thewinter months, but loss of habitat to development has forced many of theminto such makeshift burrows as drainage pipes and above-ground PVC pipe.We put out two nest boxes at Shollenberger Park in Petaluma, where threeowls had overwintered, but without success.
The last confirmed pair of Burrowing Owls known to breed in Sonoma Countywas spotted at Skaggs Island in 1987. Observer Robin Leong reports, "Therewas no scat or indication of burrowing owls on Skaggs or Tubbs Island. Localfarmers who were knowledgeable of the wildlife on their leased land saidthat coyotes are roaming the land, and they have eliminated both the foxand burrowing owl populations." Marge Irwin also reports no evidenceof breeding owls on Tubbs Island.
Our observers also surveyed the likely spots through the Petaluma Rivervalley and the flat areas north through Cotati, Santa Rosa and the Lagunaarea. Nothing. If anyone saw a breeding pair of Burrowing Owls in the countyduring the June/July census period, please call me at 823-0609.
A census conducted by the Point Reyes Bird Observatory in 1990-93 foundan average of about 9,000 Burrowing Owls in the state during that period.The great majority of them--7,000 individuals--were found along irrigationcanals near the Salton Sea in Imperial County. Interestingly, accordingto project leader Dave DeSante the owls were completely missing from comparablehabitat at the north end of the Sea, in Riverside County, where poison hadbeen set out for ground squirrels along the canals. According to Herb Clarke,a Southern California authority, the Burrowing Owl population in the southlandis "collapsed or rapidly collapsing". The statewide census willbe repeated in the years 2000-2003.
We will be watching for the return of our Burrowing Owls to Sonoma Countythis fall.