Publications by authors named "D Hannay"

Measurements of the source levels of 9880 passes of 3188 different large commercial ships from the Enhancing Cetacean Habitat and Observation (ECHO) program database were used to investigate the dependencies of vessel underwater noise emissions on several vessel design parameters and operating conditions. Trends in the dataset were analyzed using functional regression analysis, which is an extension of standard regression analysis and represents a response variable (decidecade band source level) as a continuous function of a predictor variable (frequency). The statistical model was applied to source level data for six vessel categories: cruise ships, container ships, bulk carriers, tankers, tugs, and vehicle carriers.

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Article Synopsis
  • There is increasing concern about the effects of noise from ships and small boats on important fish species, such as Pacific herring and juvenile salmon.
  • Researchers conducted experiments to measure the behavioral responses of these fish to noise from boats traveling at different speeds, finding that specific noise levels triggered behavioral changes.
  • The findings suggest that repeated exposure to boat noise can lead to increased energy use and reduced foraging efficiency in fish, highlighting the need to understand the broader ecological impacts of anthropogenic noise.
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The habitat of the endangered southern resident killer whale (SRKW) overlaps major international shipping lanes near the Port of Vancouver, British Columbia. Shipping is a dominant source of underwater noise, which can hinder SRKW key life functions. To reduce environmental pressure on the SRKWs, Vancouver Fraser Port Authority offers incentives for quieter ships.

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The problem of estimating spatial distribution and density of vocalizing marine animals is addressed. The proposed solution is based on using a fixed compact array of synchronized hydrophones and statistically optimal detection and estimation algorithms. The closed-form representations of the practical algorithms are presented.

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During 2017, the Vancouver Fraser Port Authority's Enhancing Cetacean Habitat and Observation program carried out a two-month voluntary vessel slowdown trial to determine whether slowing to 11 knots was an effective method for reducing underwater radiated vessel noise. The trial was carried out in Haro Strait, British Columbia, in critical habitat of endangered southern resident killer whales. During the trial, vessel noise measurements were collected next to shipping lanes on two hydrophones inside the Haro Strait slowdown zone, while a third hydrophone in Strait of Georgia measured vessels noise outside the slowdown zone.

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