SR3’s Dr. Holly Fearnbach finished a successful first month of fieldwork in the coastal waters of
San Diego County. Holly and her colleagues, Drs. John Durban and Dave Weller from NOAA
Southwest Fisheries Science Center (SWFSC) are using an unmanned hexacopter to obtain
vertical images to assess size, body condition and pregnancy rates of individual dolphins and
large whales. The team has flown 15 flights over 28 individual bottlenose dolphins, two groups
of long-beaked common dolphins (~130 individuals), one minke whale, and one juvenile gray
whale during its southbound migration. Aerial images of bottlenose dolphins will be matched to
the long-term photo-identification catalog maintained by SWFSC, allowing measurements to be
linked to individuals with known life histories. Common dolphin images will provide further
baseline data on group demography, spacing behavior and swim speeds for this species and gray
whale images will be included in the SWFSC/SR3 ongoing gray whale health assessment
project. Length and condition of individual gray whales will be compared between the
southbound migration to breeding grounds in Mexico in early winter and northbound migrations
to feeding grounds in the North Pacific in late spring. The team only observed and photographed
the young gray whale for about 20 minutes, but during that time it swam past more than a dozen
lobster pots (see photo). Entanglement in fishing gear is an increasing concern for large whales
as they navigate coastal waters during migration.
Aerial images of a female bottlenose dolphin and her calf (right) and a juvenile gray whale
swimming in close proximity to a lobster pot (left). Entanglement in fishing gear is an
increasing concern for large whales as they navigate coastal waters during migration. Images
were collected in the coastal waters off San Diego County for photogrammetry measurements
with an unmanned hexacopter at ~100ft altitude, with authorization under NMFS permit #19091.