• Sunset view of Glacier Bay and the surrounding Fairweather Mountains.

    Glacier Bay

    National Park & Preserve Alaska

Harbor Seal Research

looking-for-seals
Looking for harbor seals in Johns Hopkins Inlet
NPS
 
harbor seals

Harbor Seal Population Monitoring
How many seals are there in Glacier Bay?
Why are their numbers declining?

 
tracking a harbor seal

Tracking Glacier Bay Harbor Seals
Where do the seals go in the Winter?
Do the same seals come back each year?

 
seals on ice

Assessing Glacial Ice for Harbor Seals
As tidewater glaciers diminish, how might this effect
harbor seals that rely on icebergs?

 
seal publications

Peer-Reviewed Publications
Harbor Seal Research and Monitoring

 

Investigating Potential Causes of Seal Decline

It is unclear why seals are declining in Glacier Bay. Harbor seal population trajectories at other sites (Ketchikan and Sitka) in Southeastern Alaska have been increasing or stable and vary substantially from the continuous long-term declines documented in Glacier Bay. Hypothesized reasons for the decline include interspecific competition, predation, emigration, decreases in reproductive rate, human disturbance, disease, contaminants, and nutritional stress due to changes in prey base. To address management and conservation concerns regarding harbor seal declines in Glacier Bay National Park, a multi-agency collaborative study was initiated in 2004 aimed at addressing hypotheses related to harbor seal declines in Glacier Bay. Recent research has focused on assessing survival rates, genetics, body condition, foraging ecology, costs of human disturbance as a result of vessel traffic, assessing health and disease status, and identifying habitat use and movements of seals during the over-winter period.

Collaborating agencies and institutions include Alaska Department of Fish & Game, Alaska Fisheries Science Center-National Marine Mammal Laboratory & Auke Bay Laboratory, Alaska Sealife Center, University of Alaska Fairbanks-Wildlife Toxicology Laboratory, Moss Landing Marine Laboratory, University of Wyoming, and Oregon State University-Pinniped Ecology & Applied Research Laboratory. Data collection and analyses are currently ongoing for these projects.

 

 

Did You Know?

Mountain Goat

Both male and female mountain goats have horns. These black horns help distinguish Glacier Bay’s mountain goats from Dall sheep, which live farther inland.