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A newborn seal pup with a fluffy lanugo coat looks up.
Patient Update

Pupping Season Spotlight: Caring for an Orphaned Harbor Seal Pup

April 22, 2024
  • Malnutrition

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.

A veterinarian uses a stethoscope during a medical exam on a harbor seal pup.
Veterinary expert Dr. Cara Field performs a medical exam on a harbor seal pup patient. / Photo by Elena Graham © The Marine Mammal Center

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.  

Two trained volunteers move nets through a pool while seal pups swim.
Animal care volunteers ensure our hospital is clean and safe for our patients. / Photo by Clive Beavis © The Marine Mammal Center

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.  

Three newborn harbor seal pups rest at The Marine Mammal Center during rehabilitative care.
Newborn pups Avatar, Vincent and Kites rest together in a dry pen at our harbor seal hospital. / Photo by Bill Hunnewell © The Marine Mammal Center

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.

Two young seal pups rest on an orange heating pad during rehabilitative care.
Pen-mates Ricotta and Tadpole rest on top of a heating pad. / Photo by Bill Hunnewell © The Marine Mammal Center

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. 

Two trained animal care volunteers hold a young seal pup while checking its umbilical cord.
Animal care volunteers perform an umbilical swab for harbor seal pup Randa and check for signs of infection. / Photo by Clive Beavis © The Marine Mammal Center

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.

A newborn harbor seal pup is tube-fed during rehabilitative care.
A newborn harbor seal pup is gently tube-fed a nutritious formula. / Photo by Bill Hunnewell © The Marine Mammal Center

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. 

An animal care volunteer checks a harbor seal pup’s weight on a scale.
Regular weight checks (shown in kilograms) are a vital part of our patients’ rehabilitative care. / Photo by Bill Hunnewell © The Marine Mammal Center

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.

Four harbor seal pups with uniquely colored and labeled tags on their head swim in a pool during rehabilitative care.
Harbor seal pups Serrano, Calev, Sjora and Kites can quickly be identified by looking at their unique hat tags. / Photo by Bill Hunnewell © The Marine Mammal Center

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. 

A trained volunteer wearing purple gloves hand feeds a fish to a young seal pup.
Harbor seal pup Crabber is introduced to fish through hand feeding. / Photo by Clive Beavis © The Marine Mammal Center
Three trained volunteers feed fish to harbor seal pups by hand and using tongs.
Harbor seal pups can learn to eat fish at their own pace during fish school. / Photo by Bill Hunnewell © The Marine Mammal Center
A trained volunteer pulls a fish on a string through the water near a harbor seal pup during rehabilitation.
A trained volunteer drags fish on a string through the water to stimulate the pup’s natural instinct to catch prey. / Photo by Bill Hunnewell © The Marine Mammal Center
Two trained volunteers pour a bucket of fish in a rehabilitation pool for harbor seal pups to free feed.
Free feeding is the final lesson in fish school once the seals know the basics of hunting. / Photo by Bill Hunnewell © The Marine Mammal Center
A harbor seal pup looks up from the water with a fish in its mouth.
Crabber shows our animal care experts that he is learning the hunting skills needed to thrive in the wild. / Photo by Clive Beavis © The Marine Mammal Center

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.

A seal pup swims with a fish in its mouth near a feeding box at the bottom of a rehabilitation pool.
Harbor seal Maww practices her problem-solving skills by finding a fish in the feeding box at the bottom of the pool. / Photo by Karli Rice Chudeau © The Marine Mammal Center

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.

Two harbor seal pups rest in front of a rehabilitation pool.
Pen-mates Sandia (right) and Spaulding (left) receive critical care thanks to support from people like you. / Photo by Clive Beavis © The Marine Mammal Center

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

Yes, I want to save a life!

Yes, I want to save a life!

You’ll be giving sick and injured animals the best possible care at the Center’s state-of-the-art hospital. With your gift today, you are giving a patient a second chance at life in the wild.

  • $35 You'll buy food for a hungry animal
  • $45 You'll provide life-saving medical care
  • $65 You'll make second chances possible

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