Dr.
David Potter
Chief, Fisheries Sampling Branch
NMFS, Northeast Fisheries Science Center Atlantic
Right Whale Photogrammetry
![Picture of Atlantic Right Whale Photogrammetry](images/2_projects_1.jpg)
In the study of biological systems we learn most about
plants and animals buy collecting specimens of various
ages, measure them weight them, check their sex, get
their age at maturity, feed them and measure growth
rates etc. We might put radio collars on some of them
and let them go to follow migratory patterns and observer
habitat usage. There are many kinds of studies that
can be done. However, when your subjects are born weighting
5000 lbs, and grow to 45 feet long weighting up to 60,000
lbs you may have a problem. Add to this that the animals
have this habit of ‘disappearing’ from our
view about 45 minutes of every hour and you have a very
difficult animal to study. Of course I am referring
here to the study of cetaceans or whales, and specifically
in this instance to the study of the North Atlantic
right whale, considered the most endangered of the great
whales in the ocean today. Their population has hovered
around 320-350 animals for many years and show little
signs of recovery in spite of years of protection through
the Marine Mammal Protection Act, the Endangered Species
Act and the moratorium on whaling adopted by the International
Whaling Commission. Biologists today are studying these
animals to try and understand why their recovery to
some optimal population level is so slow. We know man
has impacts beyond simply harvesting the animals directly,
our ships strike animals resting on the surface and
sometimes our fishing gear gets tangled around the whales.
Either of these two events can cause death in these
animals either immediately or after some time if an
infection sets in.
Many of the questions that we ask can only be answered
by approaching the animals and collecting small skin
and blubber samples to look at the genetics, sex, and
perhaps contaminant loading picked up through their
food chain. Of course we would prefer to not disturb
these animals at all if possible to collect data that
will help us understand their plight.
Right whales were named that because they were the right
whale to hunt. They floated when killed, gave lots of
whale oil and to stayed near the coast (out to100 miles
or so). They also travel from the coast of Florida in
the winter months to US/Canadian waters in the summer.
A large area to cover and study. This range in travel
and the fact that they are coastal, makes them perfect
candidates for aerial platforms to study them.
NOAA’s Aircraft Operations Center has been working
with the National Marine Fisheries Service’s Northeast
Fisheries Science Center for 10 years conducting surveys
of cetaceans and seals along our coasts. This collaboration
has been extremely successful in planning and executing
surveys for many species. The engineering division at
AOC assists us with hardware development and mounting
on the aircraft in accordance with FAA regulations,
the maintenance group responds to the required maintenance
intervals by traveling anywhere the plane is working
to conduct the required periodic maintenance inspections.
AOC’s planning and coordination of these maintenance
events results in minimal down time for the aircraft
compared to contracted platforms. This year NOAA’s
Twin Otters flew 45 hours in support of the Right Whale
Photogrammetry mission.
Most
recently the aircraft’s mission has been to study
the right whale through the use of surplus military
reconnaissance cameras. These cameras are custom mounted
into the belly window of the NOAA Twin Otter aircraft
(see photo) and through the use of motion compensation
and a radar altimeter allow for precision photographs.
These photographs are used to identify individual right
whales due to unique patterns of callosities on their
heads. Additionally we can take detailed measurements
of the animals from these photographs and get overall
length, width and fluke width to name a few. These measurements
can be used to obtain a measure of the condition of
the animals, lean or malnourished animals readily stand
out as do pregnant females.
This study, just finishing up its third year has some
exciting results already and which will only continue
to expand as more years worth of data track individuals
throughout their life span. The NOAA aircraft and their
skilled pilots are critical to this mission for NOAA.
The aircraft is perfect to carry the instrument and
the staff needed to operate it in a safe and practical
methodology. The Twin Otters large wing surfaces and
powerful turbine engines actually allow the plane to
go low and slow with minimum risk. The aircraft is very
quiet in the survey mode and appears to have little
to no obvious effect on the animals below. The pilots
quickly learned the difficult tasks of acquiring targets
and making passes minimizing the pitch and roll characteristics
of the aircraft, maintaining constant altitude and lining
the animals up directly below the belly window.
The
partnership of AOC and NMFS to collect critical biological
information on our most endangered species of great
whales will hopefully continue into the future and perhaps
through this joint effort offer some insights into their
survival.
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