75255 Data Set Published / External 75251 Marine Development and Ecology Branch (MDEB) GIS Data Hub Project The NEFSC has been conducting aerial surveys of gray seal pupping colonies since 2000 to monitor the number of pups born in U.S. waters. Surveys are flown from either a Cessna 252, Cessna Skymaster, or NOAA Twin Otter at altitudes ranging from 180-230 meters, using hand-held or belly-mounted Canon camera systems. Surveys may also be conducted with Uncrewed Aircraft Systems (UAS) at select colonies. Ideally, surveys are flown after all pups are born and before they start leaving the colony, but in some years surveys may have been flown before or after this optimal window. Furthermore, not all colonies may have been surveyed each year due to logistics or if the site was not yet an established pupping colony. The Northeast Fisheries Science Center has been conducting aerial surveys of harbor seals since 1981 to monitor the abundance of the population in U.S. waters. Surveys are flown during the pupping season when animals are concentrated on the coast of Maine and timed to coincide with peak pupping estimated to be around the end of May. Surveys are flown from a NOAA Twin Otter at 230 meters within 2 hours of low tide using a hand-held Canon camera and fixed 300mm lens. Close to 1,000 ledges are surveyed and grouped into bay units for analysis. NEFSC Protected Species Division Pinniped Research. Seal Aerial NEFSC scientific survey Theme ISO 19115 Topic Category biota Theme ISO 19115 Topic Category environment Theme ISO 19115 Topic Category oceans Data Set NOAA National Marine Fisheries Service (NMFS) Northeast Fisheries Science Center (NEFSC) Metadata Contact 2025-03-31 Person Hatch, Joshua M joshua.hatch@noaa.gov 28 Tarzwell Drive Narragansett RI 02882 (508) 495-2084 , Michael Point of Contact 2025-03-31 Person Josephson, Elizabeth elizabeth.josephson@noaa.gov 166 Water Street Woods Hole MA 02543-1026 USA 508-495-2362 Publication Date -70.91666618 -66.97502064 44.93096407 41.26332486 Unclassified These data were produced by NOAA and are not subject to copyright protection in the United States. NOAA waives any potential copyright and related rights in these data worldwide through the Creative Commons Zero 1.0 Universal Public Domain Dedication (CC0 1.0). https://services2.arcgis.com/C8EMgrsFcRFL6LrL/arcgis/rest/services/Seal_Aerial_Survey/FeatureServer Data access URL ESRI REST Service gov.noaa.nmfs.inport:75255 Nicole Mucci 2025-03-12T15:54:20 Joshua Hatch 2026-05-06T16:26:59 2026-05-06 Northeast Fisheries Science Center NEFSC 166 Water Street Woods Hole MA 02543-1026 USA (508)495-2000 https://www.nefsc.noaa.gov 8:00 a.m. to 4:30 p.m. Monday - Friday 1001 Public No No 1 Year