Apologies this is a bit late...
Marine Mammal Science
© 2010 Society for Marine Mammalogy
Volume 26, Issue 4 Page 761-1001
<http://onlinelibrary.wiley.com/doi/10.1111/mms.2010.26.issue-4/issuetoc>
Visual and acoustic surveys for North Atlantic right whales, Eubalaena glacialis, in Cape Cod
Bay, Massachusetts, 2001–2005: Management implications (pages 837–854)
Christopher W. Clark, Moira W. Brown and Peter Corkeron
Abstract
North Atlantic right whales, /Eubalaena glacialis/, remain endangered,
primarily due to excessive anthropogenic mortality. Current management protocols
in US waters are triggered by identifying the presence of at least one right
whale in a management area. We assessed whether acoustic detection of right
whale contact calls can work as an alternative to visual aerial surveys for
establishing their presence. Aerial survey and acoustic monitoring were
conducted in Cape Cod Bay, Massachusetts, in 2001–2005 and used to evaluate and
compare right whale detections. Over the 58 d with simultaneous aerial and
acoustic coverage, aerial surveys saw whales on approximately two-thirds of the
days during which acoustic monitoring heard whales. There was no strong
relationship between numbers of whales seen during aerial surveys and numbers of
contact calls detected on survey days. Results indicate acoustic monitoring is a
more reliable mechanism than aerial survey for detecting right whales. Because
simple detection is sufficient to trigger current management protocols,
continuous, autonomous acoustic monitoring provides information of immediate
management utility more reliably than aerial surveillance. Aerial surveys are
still required to provide data for estimating population parameters and for
visually assessing the frequency and severity of injuries from shipping and
fishing and detecting injured and entangled right whales.
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