Conservation of seals at Alaska

• Context (DTE): Scientists and Indigenous leaders team up to conserve seals at Yakutat, Alaska.

Ancestral balance between people and nature

• Migrating clans of the Eyak, Ahtna and Tlingit tribes settled the Yakutat fjord as the glacier retreated.
• Clan leaders managed the hunt to avoid premature harvesting, overhunting or waste.
• Tlingit residents continue this way of life in modern form, harvesting more than 100 different fish, birds, sea mammals, land game and plants for subsistence use.
• Harbour seals are the most important; their rich meat and blubber are prepared using traditional recipes and eaten at everyday meals and memorial potlatch feasts.

Reasons for decline

Commercial hunting

• The US purchase of Alaska from Russia in 1867 disrupted traditional sealing at Yakutat.
• Yakutat was a principal hunting ground for the new industry from about 1870 to 1915.
• Commercial hunting overtaxed seals’ capacity to reproduce, and the population crashed in the 1920s.
• In the 1960s, the rise in prices for skins led to hunting exceeding the sustainable yield.
• The seal population declined by 80 per cent—90 per cent.
• Commercial sealing ended in 1972 with the Marine Mammal Protection Act, yet seals never recovered.

Climatic factors

• Ocean warming, driven by global climate change and an unfavourable cycle of the Pacific Decadal Oscillation, has reduced the number of fish that are important in seals’ diets.

Conservation efforts

• Natives have changed their diet & reduced hunting, allowing the seals to raise their pups undisturbed.
• The community cooperates with the authorities to monitor and co-manage the herd, contributing their indigenous expertise.
• They have also been active in efforts to protect the seal rookery from disturbance by cruise ships.
• The Yakutat people are recommitting to ancestral principles of responsible care and spiritual regard for seals, seeking to ensure the species’ survival.

Harbour Seal (Phoca vitulina) These are “true seals” of the Phocidae family, also sometimes called “common” or “hair” seals. They are covered with short, stiff, bristle-like hair. Colouration varies, but two basic patterns occur: light grey sides and belly with dark blotches or spots or a dark background with light rings. Only a small hole on either side of their heads, with no ear flaps, distinguishes them from sea lions. Harbour seals have a metabolic rate higher than land mammals of similar size, allowing them to generate a greater amount of body heat. They are good swimmers. However, on land, they move awkwardly by undulating in a caterpillar-like motion because their pelvic bones are fused. They can remain submerged for over 20 minutes. Oxygen-conserving adaptations that allow such dives include high blood volume, reduced peripheral circulation, reduced heart rate, and high levels of myoglobin (the oxygen-binding protein in muscle). Harbour seals periodically emerge from the water to rest, give birth, and nurse their pups. In winter, they spend up to 80% of their time in the water. Young pups are able to swim almost immediately after birth. Mature females mate shortly after weaning their pups. The embryo’s development is suspended for about 11 weeks, a trait called embryonic diapause (i.e., delayed implantation). Diet: Fishes, octopus, and squid. Behaviour: Usually solitary in water, but haul out in groups of a few to thousands. Range: The North Atlantic and Pacific oceans. Alaska’s coast extends from Dixon Entrance north to Kuskokwim Bay and west throughout the Aleutian Islands. IUCN status: LC. Credits: Alskasealife