Marine Mammal Stranding
WHY DO MARINE MAMMALS GET STRANDED?
Contact for page content: Liam Antrim
Why marine mammals strand is not completely understood by scientists. Stranding behaviors appear to
vary from species to species and by location and involves many of the following factors:
- complex oceanographic and topographic features
- extreme low tides
- weather conditions
- natural toxins
- geomagnetic disturbances and errors in navigation
- following prey inshore
- disturbance of echolocation in shallow water
- social cohesion
- human-related injuries
Seals and sea lions often spend several hours hauled out on beaches, rocks or islands. Notify the
stranding network if you observe a:
- lone seal pup
- wounded seal or sea lion
- seal or sea lion hauled out in an unusual place (i.e. busy beach or boat ramp)
Seal pups often rest on shore. Do not disturb them - it's the law!
Whales, dolphins and porpoises should always be in the water. If you observe a live whale, dolphin
or porpoise on the beach call the stranding network immediately! If the animal is dead, please
notify the network as soon as possible.
WHAT CAN YOU DO IF YOU SEE A STRANDED MARINE MAMMAL?
- Move, touch or disturb the animal...Many species can bite and carry diseases, some of which are
communicable to humans!
- Try to feed the animal
- Pour water on a seal or sea lion&endash;they are often hauled out to dry off and warm up!
- Stay a safe distance away - for your sake
- Keep other people and dogs away
- Try to observe the following and report:
1. is the animal alive or dead?
2. about how big is it in relation to you? What other general features do you observe (color,
shape, does it have fur, ears, fins etc.)
3. do you see any wounds or distinguishing marks?
4. does the animal have any visible tags ( note: seals are tagged on the hind flipper; sea lions
are tagged on the fore-flipper)? What color is the tag and can you safely read the number on the
5. what is the exact location of the animal ? (look around for landmarks if possible - it is often
difficult to locate a stranded marine mammal without detailed directions)
If possible, take a picture of the stranded animal (this is especially important if you are in a
To report a stranded marine mammal notify the nearest State Park or National Park Ranger Station or
call Olympic Coast National Marine Sanctuary 360/457-6622 .
Reporting marine mammal strandings is probably the best way you can help stranded animals. However,
wildlife experts have learned that little can be done to "rescue" animals that have come ashore -
the most humane action may be to let nature run its course. Your phone call, however, alerts
wildlife professionals to a valuable opportunity to study marine mammals and protect both the
animal and unknowing bystanders from possible harm. A few rare species have never been seen alive,
and the only information we have has come from beached individuals. All of these animals have great
In order to learn more about these puzzling events, and to obtain scientific data about marine
mammals in general, scientists respond to reports of strandings and have organized the Northwest
Marine Mammal Stranding Network.
Northwest Marine Mammal Stranding Network
was established by the National Marine Fisheries
Service under the Marine Mammal Protection Act of 1972. It is designed to respond to marine mammal
stranding events along the Washington and Oregon coasts and is part of a nationwide network. The
network is composed of cooperating scientific investigators and institutions, volunteer individuals
and organizations, wildlife and fisheries agencies, and state and federal enforcement agencies.
These participants are experienced and knowledgeable in the methods of handling beached and
stranded marine mammals and volunteer to either respond directly or provide expert advice to those
at the stranding on how to handle the incident. Data are collected from such events and entered
into a national database that is used to establish baseline information on marine mammal
communities and their health.