Seaside Aquarium Reminder: It’s Harbor Seal Pupping Season from March to August – Give them plenty of space and do not touch

From Tiffany Boothe, Seaside Aquarium/Marine Mammal Stranding Network
Spring is in the air and seal pups are about to start popping up along the Pacific Northwest coast.

Oregon and Washington typically see harbor seals born throughout spring and into late summer, while California may see pups early as February. These young animals use time on land to regulate body temperature and rest while their mothers hunt nearby. However, the mother may not return if humans are too close. Thus, wildlife experts suggest giving seal pups plenty of space, observe them from a distance and while they are absolutely adorable do not touch.

Female seals birth annually after an eleven-month gestation and utilize familiar coastal shores or estuary areas with easy access to water to have their pups. New seals can immediately swim but stay close and ride on their mothers back while they mature.

Baby seals often double in size from birth in 4-6 weeks on a regular diet of mother’s milk with 40% milk fat. While the extra layer of fat makes the pups adorable, the pups depend on that stored body fat to survive foraging on their own as they become more independent. Any interference from humans that could cause early separation between newborn pup and mother could be detrimental to the pup’s ability to survive.


Marine mammals are protected under the Marine Mammal Protection Act. Under this federal law it is illegal to move, touch, harass, feed, or kill marine mammals including seal pups. Harbor seals live on land for nearly half their lives breeding, molting, resting, and raising their offspring. Molting occurs after pups are weaned and to retain warmth and energy molting seals often stay on land for extended periods of time. Human encroachment and domestic dog interaction are big challenges for the health and well-being of both young and mature seals.

If you come across a seal pup, please contact the Marine Mammal Stranding Network. Local wildlife officials will post educational signs that encourage the public to keep a safe distance away from the animal while the situation is monitored by experts. Most of the time the animal is healthy and in need of a rest before it rejoins with its mother or re-enters the water.

The Marine Mammal Stranding Network responds to sightings of seal pups and other injured or dead marine mammals (including whales or dolphins). Responders will act as quickly as possible to assess the situation and obtain information and observations about the animal in question.

For the northern Oregon and southern Washington coast the Seaside Aquarium is the local responder for the Marine Mammal Stranding Network and can be contacted at 503.738.6211. If a stranded marine mammal is found elsewhere the Marine Mammal Hotline at 1.800.452.7888 and they will contact the appropriate stranding network responder for the area.