The cowbird trap placed at English Creek near Peyton Drive and Eucalyptus Avenue in Chino Hills has been replenished after it was found empty two weeks ago with the door wide open.
According to Melody Aimar, lead biologist with the Santa Ana Watershed Association, the trap was closed for a few days to discourage a hawk that was getting too interested in a potential free meal.
“When we close a trap, we always remove the food and water so as not to attract birds and other animals,” she said. “We keep the door open to avoid unintended captures.”
Five cowbirds have been placed in the trap to attract their fellow species and lure them away from an endangered songbird in the nearby habitat called the “least Bell’s vireo” which is not doing well in Chino Hills because of the cowbird, according to Ms. Aimar.
The cowbird is considered a “brood parasite” because it lays eggs in the nests of the least Bell’s vireo and other species.
The songbird often leaves her nest when this occurs, and her eggs perish.