Alaska Harbor Seal Glacial Surveys

Description

Floating glacial ice serves as a haul-out substrate for a significant number (10-15%) of Alaskan harbor seals, and thus surveying tidewater glacial fjords is an important component of statewide efforts to estimate seal abundance. Surveys conducted during pupping suggest that glacial haul outs have higher than average productivity and thus may serve as important source populations statewide. The availability of ice for hauling out varies with seasonal glacial dynamics, but over decades of climate change most tidewater glaciers are now retreating toward eventual grounding with many already ceasing to calve ice into the water. Compounding glacial retreat and thinning is the trend at most of these sites toward increasing tourism and a low compliance of tour vessels to seal approach guidelines and regulations. It is thus important to track glacial populations over the long-term especially as various impacts may degrade seal habitat leading to fewer glacial seals and potential impacts to the population state-wide. There are currently 28 glacial sites that have at least one actively calving tidewater glacier and in turn seals that haul out on the ice during the seals’ molting period, when most surveys have occurred. Due to concerns about vessel disturbance, Disenchantment and Icy Bays have been surveyed during molting almost annually between 2001-2011 (ex 2003); surveys occurred during pupping and molting in 2004 and 2005, and have occurred just during molting apx. every other year since 2011. Johns Hopkins Inlet in Glacier Bay has been surveyed annually using these methods since 2007, with surveys occurring during both pupping and molting. The remaining 25 sites have been surveyed on an opportunistic schedule (based on weather and aircraft availability), which for most sites equates to about every 2-3 years. Some of the smallest sites have been surveyed on a 4-5 year schedule. These schedules will likely continue with more abundant sites in Prince William Sound (e.g., College Fjord and Columbia) and Southeast Alaska (Tracy Arm, Endicott Arm, LeConte Bay, and Glacier Bay) having higher priority and contingent on management concerns.

Resources

Name Format Description Link
0 The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords. https://www.earthdata.nasa.gov/learn/find-data/idn/gcmd-keywords
33 NOAA Data Management Plan for this record on InPort. https://www.fisheries.noaa.gov/inportserve/waf/noaa/nmfs/afsc/dmp/pdf/17348.pdf
33 Using Aerial Photography of Harbor Seals to Compare Timing of Pupping and Weaning at Two Glacial Fjords http://access.afsc.noaa.gov/pubs/posters/pdfs/pJansen07_aerial_photography-harbor-seals.pdf
0 View the complete metadata record on InPort for more information about this dataset. https://www.fisheries.noaa.gov/inport/item/17348
0 AKFSC Home Page https://www.fisheries.noaa.gov/about/alaska-fisheries-science-center
21 AFSC Quarterly Report Article http://www.afsc.noaa.gov/Quarterly/jas2007/divrptsNMML5.htm
33 Ebbs and Floes of Seals: Using Aerial Photo-Mosaics to Track Changes in Abundance of Harbor Seals on Ice http://access.afsc.noaa.gov/pubs/posters/pdfs/pJansen05_ebb-floe-aerial-seal.pdf
33 Publication describing the LATTE (sampling) method used during aerial surveys: Jansen JK, Brady GM, Ver Hoef JM, Boveng PL (2015) Spatially Estimating Disturbance of Harbor Seals (Phoca vitulina). PLoS ONE 10(7):e0129798. doi:10.1371/journal.pone.0129798 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4488586/pdf/pone.0129798.pdf
0 View the complete metadata record on InPort for more information about this dataset. https://www.fisheries.noaa.gov/inport/item/17348
0 AKFSC Home Page https://www.fisheries.noaa.gov/about/alaska-fisheries-science-center
21 AFSC Quarterly Report Article https://www.afsc.noaa.gov/Quarterly/jas2007/divrptsNMML5.htm
33 Ebbs and Floes of Seals: Using Aerial Photo-Mosaics to Track Changes in Abundance of Harbor Seals on Ice https://access.afsc.noaa.gov/pubs/posters/pdfs/pJansen05_ebb-floe-aerial-seal.pdf
33 Publication describing the LATTE (sampling) method used during aerial surveys: Jansen JK, Brady GM, Ver Hoef JM, Boveng PL (2015) Spatially Estimating Disturbance of Harbor Seals (Phoca vitulina). PLoS ONE 10(7):e0129798. doi:10.1371/journal.pone.0129798 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4488586/pdf/pone.0129798.pdf
33 Using Aerial Photography of Harbor Seals to Compare Timing of Pupping and Weaning at Two Glacial Fjords https://access.afsc.noaa.gov/pubs/posters/pdfs/pJansen07_aerial_photography-harbor-seals.pdf
0 Global Change Master Directory (GCMD). 2024. GCMD Keywords, Version 19. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords
33 NOAA Data Management Plan for this record on InPort. https://www.fisheries.noaa.gov/inportserve/waf/noaa/nmfs/afsc/dmp/pdf/17348.pdf

Tags

  • alaska fisheries science center
  • alaska
  • harbor seal
  • noaa
  • gulf of alaska
  • u.s. department of commerce
  • tidewater glacier
  • national marine fisheries service
  • doc/noaa/nmfs/afsc
  • alaska harbor seal surveys and abundance

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