| Brown-headed Cowbird nest parasitism is recognized as a problem for many endangered and sensitive bird species. As a result, managers use cowbird control programs to reduce parasitism. Cowbird traps are the primary method for reducing cowbird populations; investigators may also remove cowbird eggs in host nests and occasionally supplement traps with shooting. Unfortunately, cowbird trapping can be expensive, is limited to areas with vehicle access, and can result in the death or nest failure of many non-target birds. Removing cowbird eggs and shooting also have their drawbacks. Thus, we investigated whether target-netting for cowbird females is effective for controlling cowbirds near areas where the target host is nesting. In 2015, we target-netted female cowbirds in California and compared those results with trapping. The target-netting involved using mist nets, a female cowbird decoy, and cowbird calls. We captured 38 female cowbirds with target-netting, and nine female cowbirds with traps. The capture rate for netting was 0.46 females/hour and 0.04 females/hour for trapping. The number of non-target captures per female cowbird captured was much lower with netting (2.07) compared to trapping (9.22). Our results indicate that netting for female cowbirds is highly effective to remove cowbirds from areas with less impact to non-target species.
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