a rare visitor from antarctic pack ice
- Size
- Length: 200–250 cm, Weight: 200–300 kg
- Lifespan
- 20–25 years
- Diet
- Carnivorous. Feeds on Antarctic krill. Has specialised teeth that act as a sieve to filter krill from the water.
- Habitat
- Antarctic pack ice and open ocean. In New Zealand, recorded as a vagrant on beaches and rocky shores. Requires cold, subantarctic conditions.
- Range
- Very rare visitor to New Zealand waters from Antarctica. Most records are from the subantarctic islands and the South Island coast. Not resident.
- Endemism
- Visitor
- Main Threats
- No significant threats in New Zealand waters as it is a very rare visitor. Climate change affecting Antarctic sea ice and krill populations is the primary global concern.
- Population
- This species is a very rare visitor to New Zealand from Antarctica. Only a handful of records exist. Globally it is one of the most abundant seals.
- Conservation Status
- data_deficient
- Human Risk
- caution
- Handling Note
- large seal, fast on land bites are severe keep well clear
- Conservation Note
- Rare vagrant seal from Antarctic pack ice; not assessed for conservation status in New Zealand.
- Te Ao Māori
- The crabeater seal has no Māori name. It was never seen by Māori before European exploration of Antarctica. Its rare appearances on New Zealand shores are a modern phenomenon. A consequence of changing ocean conditions and increased human presence in the southern ocean. It is a visitor from the ice. A creature of a world that most New Zealanders will never see. To find one on a beach is to be reminded that Antarctica is not as far away as it seems.
A very rare visitor to New Zealand from Antarctica. A seal that is lost. This seal is one of the most abundant seals in the world. Yet it is almost never seen in New Zealand waters. Despite its name, it eats krill, not crabs. The name crabeater is a mistranslation. The species has specialised teeth that interlock to form a sieve. It filters tiny krill from the water as it swims with its mouth open. It is a highly specialised feeder. Adapted to life in the pack ice where krill swarms are dense. A seal that eats krill, not crabs.
The crabeater seal's teeth are a marvel of evolution. Each tooth has multiple cusps that fit together like the teeth of a comb. When the seal closes its mouth, water is forced out through the gaps. The krill are trapped inside. The seal then swallows its catch whole. This feeding method is efficient but inflexible. The crabeater cannot easily switch to other prey if krill become scarce. That makes it vulnerable to climate change. As the Antarctic ice melts, the krill populations shift. The seals must follow.
Why does it sometimes reach New Zealand? The individuals found here are almost certainly lost. They may have been disoriented by storms. Carried north by unusual currents. They may be sick or starving.
A crabeater seal on a New Zealand beach is a seal in trouble. The beach is cold. The seal rests on the sand. Lost. Far from the ice. It should be eating krill in Antarctica. It is here instead. No one knows why. It will not say. It stays for a while. Then slips back into the sea.
It may return south. It may die. Either way, its visit is brief. It does not know it is a rare visitor. It just wanted to rest.