Upper Midwest Environmental Sciences Center
Thermoregulatory effects of radiotelemetry transmitters on mallard ducklings
Bakken, G. S., Reynolds, P. S., Kenow, K. P., Korschgen, C. E., and Boysen, A. F., 1996, Thermoregulatory effects of radiotelemetry transmitters on mallard ducklings: Journal of Wildlife Management, v. 60, no. 3, p. 669-678.
Many telemetry transmitter attachments disrupt downy insulation, and may bias survival studies during cold weather by making ducklings more susceptible to chilling. We compared thermal responses of untreated 1-day-old mallards (Anas platyrhynchos) to ducklings carrying external sutured backpack or subcutaneously implanted transmitters. Ducklings carrying external transmitters showed areas of increased surface temperature in thermographic images. However, open-circuit respirometry studies at 5, 10, 15, 20, and 25 C and wind speeds of 0.1, 0.2, 0.5, and 1 m/s indicated no biologically significant differences in total heat production, net heat production, or short-term body mass loss. These results do not exclude the possibility of other negative effects of transmitters on duckling behavior and survival.
Keywords: Anas platyrhynchos, evaporative cooling, mallards, metabolic rate, radiotelemetry, recruitment, radio transmitters, metabolism chamber, oxygen consumption, wild mallards, wind, behavior, temperature, canvasbacks, animals, ducks