Harbor Seal
Phoca vitulina
The banana-posing, whisker-powered fish detective of the coast.
The harbor seal is the one most people meet first — a speckled, big-eyed animal hauled out on a rock with both ends curled up. Underneath the cuteness is a diving machine that can find a fish it never saw, using nothing but its whiskers.
- Length
- 1.5–1.9 m (5–6 ft)
- Weight
- 70–150 kg
- Lifespan
- 25–30 years
- Diet
- Fish, squid, crustaceans
- Dive depth
- Up to 450 m
- Heart rate diving
- Drops to about 4 bpm
The good stuff.
Whiskers that read the water
Harbor seal whiskers are wavy, not straight, which stops them from vibrating in the seal's own wake. They can follow the invisible trail of turbulence a fish left behind more than half a minute earlier — blindfolded.
The banana pose has a job
Head up, tail up, belly on the rock. It keeps the most heat in and the least skin in contact with cold, wet ground. It looks silly. It's thermodynamics.
Pups swim on day one
A harbor seal pup can swim and dive within hours of being born, and follows its mother into the water almost immediately. They nurse for only about four weeks.
They sleep underwater
Harbor seals can nap on the seafloor or hang vertically in the water like a bottle, surfacing to breathe without properly waking up.
Every coat is a different animal
The pattern of spots and rings is unique to each seal, so researchers photograph them the way you'd take a mugshot — no tagging needed.
They can't walk
True seals have no ear flaps and can't rotate their back flippers forward, so on land they inchworm along on their belly. Sea lions can walk. Seals bounce.
Wait, really?
- ✦
They can hold their breath for around 30 minutes.
- ✦
A resting harbor seal's heart slows so much that its body can send nearly all its oxygen to the brain and heart alone.
- ✦
Their eyes have a reflective layer behind the retina, like a cat's, for seeing in dark water.
What it sounds like
Mostly quiet on land — snorts, sneezes and slaps. Males sing surprisingly musical underwater roars during breeding season.
Where you might see one
Cold and temperate coasts all around the northern hemisphere — from Scotland to Maine to Alaska to Japan.
The trouble
- Disturbance at haul-out sites
- Entanglement in nets and fishing line
- Coastal pollution
- Dogs off leash on beaches
One real thing
If you find a seal pup alone on a beach, stay at least 50 metres away and call a marine mammal rescue. It is almost certainly not abandoned — mum is out fishing and will not come back while you're standing there.
More ways to help