Since
2001, the Hawai‘i Marine Mammal Consortium (HMMC) has conducted
shore-based observations of humpback whales (Megaptera
novaeangliae) from our
research site, “Old Ruins”, located on the northwest coast of the Big
Island, approximately 65 meters above sea level, overlooking Kawaihae
Bay. Our research builds on that conducted by other research
groups (that included Adam, Chris, Susan or Yin) in the 1980’s and
1990’s, using similar methodologies.
Though humpback
whales are seen in Hawai‘i seasonally as early as
October, we focus our shore-based research on the peak of the season,
between early February and early March. During this period, we
conduct scan observations once per day in one of four alternating time
blocks (7-9 AM, 10 AM-12 noon, 1-3 PM, 4-6 PM) to approximate
equivalent coverage of all daylight hours. The goal of each
15-minute scan is to document the presence and relative position of all
marine mammals, vessels and aircraft. HMMC staff assume the roles
of observer and theodolite operator, while students and volunteers
rotate through the roles of computer operator and notetakers (including
mapper). Whale and vessel locations are measured with a
theodolite and 7x50 reticle binoculars with compass. A
theodolite is a surveyor’s instrument that measures horizontal angles
in relation to a fixed reference point, and vertical angles relative to
gravity. At the touch of a few keystokes, these angles are
transferred to an Apple Macintosh laptop, running customized software
developed by personnel at Cornell University.
Our scans add to
a long-term database on the relative distribution,
behavior and seasonal presence of humpback whales off the Kohala
Coast. In addition to numerous humpback whales, we have observed
spinner dolphins (Stenella
longirostris), false killer
whales (Pseudorca
crassidens), bottlenose
dolphins (Tursiops truncatus),
and spotted dolphins (Stenella
attenuata) from our
shore-based research site in Kohala.
To learn more
about our shore-based efforts, read the newsletters we’ve posted as well as our report
(36 pages, 776 KB) to the Department of Land and Natural Resources,
State of Hawai‘i and the Hawaiian Islands Humpback Whale National
Marine Sanctuary on trends in shore-based whale observations
1988-2003.
