A TECHNIQUE FOR DORSAL SUBCUTANEOUS IMPLANTATION OF HEART-RATE BIOTELEMETRY TRANSMITTERS IN BLACK DUCKS - APPLICATION IN AN AIRCRAFT NOISE RESPONSE STUDY

A technique for heart rate biotelemetry transmitter implantation was d eveloped to monitor heart rate fluctuations of Black Ducks (Anas rubri pes) in response to simulated aircraft noise in a large outdoor enclos ure. A dorsal subcutaneous approach, with subcutaneous tunneling of le ad wires, was employed for placement of the 32 g transmitters. A base- apex lead configuration, with leads anchored at the dorsal cervico-tho racic junction and the caudal keel, yielded the maximal ECG wave-form deflection for triggering the transmitter. Heart rates of six Black Du cks (three in each of two separate trials) were monitored for 3 days p re-noise to establish a baseline, and then for 4 days of simulated air craft noise. The noise stimulus replicated an FB-111 military jet, and was played 48 times per day at. a peak volume of 110 dB. Daily mean h eart rates, used as indicators of metabolic rates, did not increase in response to noise. Recognizable acute heart rate increases correspond ing with a noise event occurred with increased frequency during the fi rst day of noise presentation, but on subsequent days the responses di d not differ significantly from baseline. Acute heart rate responses t o aircraft noise diminished rapidly, indicating the ability of Black D ucks to habituate to the auditory component of low altitude aircraft o verflights.