Elizabeth Josephson is a data manager and drone pilot for a National Oceanic and Atmospheric Administration project using unmanned aircraft to monitor seals on a remote island off the coast of Nantucket, Massachusetts. She works for NOAA’s Northeast Fisheries Science Center.
How did you decide to start using drones for counting the seal population? The Northeast Fisheries Science Center has been using manned aircraft to survey seal haul out sites for several decades. We have been following the advances in unmanned systems for wildlife monitoring for several years, including work done by the National Marine Fisheries Service on the West Coast to survey sea lions and thought it would be good to try in our research.
Why is it important to know the number of seals?
The National Marine Fisheries Service is mandated by the Marine Mammal Protection Act to monitor and protect marine mammal stocks that occur in waters under U.S. jurisdiction. This involves gaining understanding of population sizes and the threats the animals face. We are working to understand the dynamics between our seal species and their predators and prey. Concerns are raised both by populations that appear to be increasing in our area — gray seals — and their increasing interactions with human populations, and populations that may not be increasing — harbor seals.
What are the advantages of using unmanned aircraft for this work?
While manned aircraft may be most useful for broad-scale surveys, unmanned systems have the advantages of being cheaper, safer and more easily deployed on small scales. Because of this relative ease of deployment, we can potentially increase our frequency of surveys. UAS can operate at lower altitudes with little perceived response from the animals, rotary systems can hover over targeted individuals if necessary and the photos are of high quality, so we can collect more data on individual seals, potentially including things such as health assessments.
Does using the UAS for photography change the way seal tracking is being done, versus boats or manned aircraft?
One thing we think UAS photography will be very useful for is documenting seals on the beach that have evidence of fishing gear entanglements. This is something we can sometimes see in manned aerial photography or from photographs of the seals taken from the beach or small boats, but our ability to better characterize and quantify these entanglements would be much improved with UAS photography.
Are there any challenges posed by using UAS?
I think the main challenge is the limited battery life of current systems. Complete coverage of the gray seal pupping colonies required many battery changes, even with the more efficient systems.
How long have you been monitoring the seals using drones?
This past January was our first time using UAS for monitoring seals here in the Northeast U.S.
Are there any other areas of the country that are using drones to monitor seals?
Places the National Marine Fishery Service has been using UAS to monitor seals range from surveys of stellar sea lions and ice seals in Alaska to monk seals in Hawaii.