Effects of the sounds from an artificial oil production island on bowhead whale calling behavior

Citation

Blackwell, S. B., C. R. Greene Jr, T. L. McDonald, R. M. Nielson, C. S. Nations, W. J. Richardson, and B. Streever (2007). “Effects of the sounds from an artificial oil production island on bowhead whale calling behavior”. In: The Journal of the Acoustical Society of America 122.5, p. 3058. DOI: 10.1121/1.2942906.

Number of Citations: 0

Abstract

The westward migration of bowhead whales (Balaena mysticetus) was studied during autumn 2001–2004 to examine the effects of sounds from an artificial oil production island (Northstar) on whale calling behavior. Whale calls were recorded by an array of directional autonomous seafloor acoustic recorders (DASARs) located 6.4–21.5 km northeast of Northstar in the Beaufort Sea. Simultaneously, a continuous record of sounds produced by Northstar was obtained $$450 m north of the island. More than 130,000 bowhead calls were detected, and were classified as to their type, including five types of simple calls and one complex call category. In addition, the directional capability of DASARs allowed triangulation of an estimated whale position for a majority of the calls. The primary objectives of the study were to assess any effects of Northstar sounds and environmental-physical covariates on the duration, midfrequency, frequency range, type of call, and call detection rates. The analyses showed that an increase in transient sounds from Northstar (i.e., boats) resulted in significantly shorter calls. In addition, call detection rates were significantly higher for whales upstream of the array, and the use of complex calls increased significantly as the whales swam westward past Northstar. [Study funded by BP Exploration, Alaska.]