Pupping Season Spotlight: Caring for an Orphaned Harbor Seal Pup

In mid-February, The Marine Mammal Center’s response hotline received a call from a concerned beachgoer that a small, fluffy seal pup was stranded and in need of help. Our trained response volunteers were dispatched. After carefully observing the scene, they determined that the pup was orphaned, and her life was in danger. 

Named Sandia, this tiny pup was our first harbor seal patient rescued in 2024.

It’s a normal occurrence for harbor seal mothers to leave their pups on the beach as they go to sea in search of food. But if people and dogs get too close, the seal mother may be scared away and abandon her dependent pup. The otherwise healthy newborn seal is then left on its own, defenseless and without the nutrition or skills to survive. Wildlife disturbance by people and off-leash dogs is unfortunately one of the most common reasons young seals need rescuing. 

Each spring as harbor seals are born along the California coast, our hospital fills up with young pups that are orphaned, premature, malnourished or some combination of the three. With pupping season underway, take a deep dive into the rehabilitative care that kind people like you make possible for patients like harbor seal pup Sandia.

Very young seal pups like Sandia who are separated from their mother before they finish nursing can experience stress easily and have a high risk of illness without the antibodies from their mother’s milk. That’s why at our marine mammal hospital in Sausalito, California, these pups have their very own harbor seal hospital designed specifically to meet their needs during this vulnerable age. 

Tucked away from visitors and our other seal and sea lion patients, this special hospital is quieter to alleviate stress and helps avoid cross-contamination with other patients to minimize potential transfer of viruses or bacteria. 

The Center’s harbor seal volunteer crews are specially trained to care for pups like Sandia, which includes preparing food and feeding patients, cleaning pens and pools, weighing patients and more.  

When newborn seal pups first arrive, they may initially be housed in a small, covered dry pen if they are too weak to get out of the pools on their own. Very young and malnourished seals do not have the fat reserves needed to keep warm on their own. So this area of our harbor seal hospital is protected from the wind and more temperature controlled, helping our more vulnerable patients stay warmer.  

After young pups have time to stabilize and get stronger, they are moved into the outdoor pooled pens where they can swim, dive and ultimately learn to catch food. For additional warmth, our experts provide heat pads for the pups to lie on, as well as house pups together as pen-mates so they can snuggle.

During Sandia’s admit exam, our veterinary experts saw signs revealing that she was just days old and likely born prematurely. Not only was part of her umbilical cord attached, but she still had a whitish lanugo coat that is usually shed in utero before birth. 

Just like with a human baby, a seal pup’s umbilical cord eventually shrivels into a belly button under its fur. But before the wound heals, it is a very vulnerable area as any bacteria can have a direct connection inside the body. Trained volunteers apply antiseptic to the wound and frequently check for swelling or heat so our veterinarians can be alerted at any first sign of infection. 

Since very young seal pups would still be nursing with their mother in the wild, our veterinary experts and trained volunteers initially feed them a special formula through a tube to make sure they get vital neonatal nutrients in their diet. 

Sandia needed to be fed every few hours as a growing newborn, so our animal care volunteers worked nearly around the clock to keep her nourished. The Center’s veterinarians also prescribed vitamins and antibiotics to help treat any infections and boost her fragile newborn immune system.

In the wild, harbor seal pups nurse with their mothers for about four weeks before they are weaned. The milk from a harbor seal mother is much richer and more nutritious than anything humans can provide, so it takes much longer for rescued pups to gain enough weight to sustain themselves. Our experts conduct frequent weight checks to monitor the pups’ progress and ensure they are growing at a healthy rate. 

Sandia weighed just 14 pounds when she was rescued, which is even less than what a harbor seal pup typically weighs at birth. Thanks to our dedicated animal care volunteers and support from people like you, Sandia has been gaining weight and getting much stronger. 

As our first harbor seal of the year, Sandia had no pen-mates at first. But as more pups have stranded on our beaches in need of care, she has been spending more time swimming in the pools with other young harbor seals.

Once our newborn pup patients shed their lanugo coats, biodegradable hat tags are placed on top of their heads with animal-safe glue. Etched with a unique letter or number combination, hat tags help our experts spot an individual patient with ease as we provide personalized care.

As harbor seal pups at our hospital get stronger and their teeth come in, they transition from being tube-fed to eating herring. Some of our youngest patients like Sandia arrive at our hospital not even knowing that fish is food! That’s why meals, medicine and lessons in fish school are often all part of a harbor seal pup’s treatment plan.  

During fish school, specially trained volunteers hand feed, drag fish on a string through the water or wiggle fish with tongs to encourage a seal pup’s natural instinct to chase prey. Our pup patients learn how to track, catch and eat whole fish on their own, and finally how to compete with their pen-mates for meals.  

Click through the slideshow below to see harbor seals at various stages of fish school. 

To help ensure a young seal pup like Sandia is physically and mentally prepared to survive in the wild, rehabilitative care at our hospital also includes a variety of educational enrichment activities. 

Our animal care experts use their behavioral knowledge to design enrichment for specific species like harbor seals. These innovative items include a floating raft that helps seals learn to haul out, or temporarily leave the water, and a feeding box at the bottom of the pool that helps them develop problem-solving skills.

For now, Sandia is still gaining her strength and learning the skills needed to thrive in the wild. Once Sandia and the other harbor seal pups at our hospital can show our veterinary experts that they’ve mastered the art of catching fish and receive a clean bill of health, they’ll be ready to return to their ocean home with a second chance.

Did you know that compassionate people like you provide life-saving care for orphaned harbor seals like Sandia? Your generosity will go a long way to help a marine mammal patient be released back to the wild. 

Help a seal pup like Sandia today