Premium
IMPACTS OF COMMERCIAL WHALE WATCHING ON MALE SPERM WHALES AT KAIKOURA, NEW ZEALAND
Author(s) -
Richter Christoph,
Dawson Steve,
Slooten Elisabeth
Publication year - 2006
Publication title -
marine mammal science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.723
H-Index - 78
eISSN - 1748-7692
pISSN - 0824-0469
DOI - 10.1111/j.1748-7692.2006.00005.x
Subject(s) - sperm whale , whale , cetacea , shore , fishery , sperm , biology , geography , environmental science , biochemistry , myoglobin , botany
Abstract Male sperm whales are the basis for a commercially important whale‐watching industry at Kaikoura, New Zealand. We examined the influence of whale‐watching boats and aircraft over three years using observations from an independent research boat and from shore. We employed an information‐theoretic approach to determine which factors were necessary to explain variation in blow interval, time at surface, and time to first click. In almost all analyses, models required the inclusion of the presence of the research boat or whale‐watching boats or airplanes. The only exception was the model explaining variation in blow intervals observed from shore, which required only season. We also analyzed spatial behavior at the surface. Resident whales changed direction significantly more in the presence of whale‐watching boats compared to encounters with only the research boat present. No such difference was observed for encounters with aircraft. Our results thus indicate that sperm whales off Kaikoura respond to whale‐watching activities, although these changes are small and most likely not of biological importance. However, resident whales responded less to these activities compared to transient whales, possibly indicating habituation and, more importantly, the need to monitor continued activities closely.