Counting caribou in Alaska’s largest herds has become more effective, thanks to a pair of digital aerial camera systems. The systems replace World War II-era black-and-white film cameras previously used since the 1970s and enabled biologists last summer to pinpoint numbers for the Porcupine, Fortymile, Central Arctic, Teshekpuk, and Western Arctic caribou herds.
“At least three of those herds wouldn’t have been photographed (last summer) without the new system,” said Wildlife Biologist Nate Pamperin of Fairbanks.
Biologists have long monitored caribou by flying over herds with cameras mounted in small aircraft and taking photographs as animals aggregate briefly each summer. The old systems, which featured Zeiss RMK-A large-format film cameras, functioned poorly in low light conditions, covered limited ground swaths, and cost precious time by requiring pilots to periodically land and reload film.
The digital systems each feature three medium-format 100-megapixel cameras in gyro-stabilized mounts with GPS and inertial measurement units to record position, pitch, roll, and yaw. The technology allows biologists to conduct photocensus work under low light conditions and to capture wider swaths of country.
“Our Western Arctic herd count would not have happened with film last summer because of poor light on the second day,” said Pamperin. “In several other situations this year the larger ground swath of the new system allowed us to photograph large groups that were rapidly moving or widely scattered – situations that were problematic for the film systems.”
The digital cameras produce superior color images that can be inspected immediately for quality. In addition, new software enables individual images to be stitched together and georeferenced so that each caribou group can be viewed as a single image mosaic. In the past, staff had to manually lay out 9-inch by 9-inch printed photographs, delineate overlap, and determine which parts of each photo were to be counted. It was a tedious process that sometimes took weeks to accomplish.
Photocensus counts are important caribou management tools that help biologists track and manage herd population trends. Findings are used by advisory and regulatory boards as well as state and federal wildlife managers to help determine bag limits and hunting seasons. Biologists are completing the counts of various herds photographed last summer, and results of those counts will be available soon.
The systems were purchased with funds generated by hunters and shooting sports enthusiasts through payment of federal taxes on firearms, ammunition, and archery equipment, and through state hunting license and tag fees. For more information about caribou photocensus work, contact Nate Pamperin at (907) 459-7377 or firstname.lastname@example.org.