EFFECTS OF BACK-MOUNTED RADIO PACKAGES ON BREEDING WOOD-DUCKS

The effects of back-mounted radio transmitters on reproductive effort and return rates of pre-nesting pairs and incubating female Wood Ducks (Air sponsa) were investigated. Twenty of 22 pre-nesting pairs remain ed together after capture and radio-marking, but only two females from radio-marked pairs attempted to incubate, and none were captured in n est boxes during the subsequent 2-3 breeding seasons. Nest success, du ckling survival and return rates did not differ significantly between a sample of females radio-marked during incubation and those leg-bande d only, but statistical power was low (0.11-0.32). Detrimental effects of back-mounted radio transmitters may preclude their use in studies of pre-nesting Wood Duck pairs, but back-mounted transmitters appear t o have minimal effects on incubating and brood-rearing females.