Spring Break for Seals!

Resting seals molt their skin

The spring months bring more seals to Piedras Blancas than even the winter breeding season. All 5,000 or so adult females return, along with five thousand or so non-breeding juveniles. It’s the busiest beach season for these migratory seals.

The seals look ragged, like something is wrong with them. Their skin is peeling off.  For northern elephant seals, it’s normal, the annual molt. They will be on the beach through June.

Raggedy old brown skin peels off.

Berney LeBoeuf, in his book Elephant Seals: Pushing the Limits on Land and at Sea, recounts an incident from the 1960s, when elephant seals were unfamiliar to local residents. A woman called police to investigate the scruffy-looking seal on the beach near her house. The policeman who responded agreed that the seal was suffering, and shot it to relieve its misery. “Of course, the seal was fine,” he writes, “it was just molting, as residents came to learn with the increasing influx of seals in the following years.”

Molting

Elephant seals, like only one other seal (the Hawaiian monk seal), molt their skin annually in a few weeks. All other seals molt, but gradually, one hair at a time, like dogs, so it isn’t as noticeable.

Elephant seals form a new skin layer under the old skin. Blood stops supplying the old skin. It dies and peels off in pieces. Scraps of it skitter across the beach. Friends of the Elephant Seal docents have samples of it to show visitors. Children enjoy handling it. Adults are more dubious, extending a cautious finger for a touch.

The seals stop eating when they are on the beach at the rookery, fasting for that four weeks it takes for them to complete their molt. Female seals lose about a quarter of their body weight while they lie on the beach and let their skin peel off.

The new skin and hair underneath is gray. The hairs are short, but soon stand up and grow longer. Look for pearly gray seals next to brown and tan seals.

Silvery gray among last year's brown skin and fur.

The skin begins to molt off around eyes and ears, old scars, and other body orifices. Then the belly and sides and back peel off.

Old scars remain, but temporary marks peel off with the skin. That’s one of the challenges of identifying seals for research study. Numbers bleached or dyed on the fur peel off when the skin molts. Resighting seals with dyed numbers before their skin peels off rarely happens. It depends on the luck of the seal being at a place and time when someone sees the mark and reports it.

If you see a marked seal, report it to a docent or contact elephantseal.org.

Seals can also be identified with small plastic flipper tags, but those numbers are difficult to read from a distance.

Pup embryo development

Unseen, next year’s pups are starting to develop. The females mated after they weaned their pups in February and March. That fertilized egg entered a state of embryonic diapause, or delayed implantation. Development was suspended, allowing the mother to regain blubber and condition after the weight loss of nursing her pup. Embryonic diapause times all births to happen around the same time.

These slightly pregnant females spent the next ten weeks feeding freely. Now, in April and May, their bodies prepare for the embryo to begin gestation.

Embryonic diapause happens in other mammals. In some, it’s a response to conditions. In elephant seals, all pregnancies start this way.

Juveniles

Juveniles, male and female seals not yet ready to breed, have been foraging and growing at sea while the adults dominated the beach during the winter breeding season. The beach, although crowded, is calmer now. No bulls fighting for dominance.

Seals of various sizes and ages molt together, except for the largest bulls, which are migrating. 

Bulls are on their northern migration. They will return to the beach in July and August, time for them to molt their skin.

Mercury bioaccumulation

 

The molted skin takes with it some of the mercury that the seals have accumulated from the mercury in the ocean. The mercury got there from coal-burning plants, discharged into the atmosphere and rained down on the oceans. Top predators such as elephant seals bioaccumulate it as it goes up the food chain.

 

Shed skin and other excretions from the elephant seals at Ano Nuevo are a major source of methylmercury contamination there, influencing the bottom of the food web.

 

Methyl mercury is a human neurotoxin. Mercury affects the seals’ hormone levels, immune system and the ability to reproduce successfully, which may affect the population. Research continues on how mercury may be affecting the seals.

 

Their peaceful spring rest on the beach belies the drama of their lives, within their pregnant bodies, and in the effects of human activities on their habitat.

 

 

Ellie Season for Rescuers

Stranded pups wash up on area beaches 

The pups born this season at Piedras Blancas have been weaned. They’ve developed skills to survive, and many have left the beach on their first migration. Some can’t quite make it in the ocean. They wash up on local beaches, underweight and exhausted.

“They are coming in at 30 to 40 kg (65-90 lbs), below their birth weight,” said Shayla Zink, operations manager for The Marine Mammal Center’s Morro Bay facility.

Stranded weaners may still have their black birth fur, or they may have molted that to their Silver Bullet skin, brown on their backs and silver on their bellies.

 

Three of these weaners are fat, but the one in the middle is thin. This one also hasn't fully shed its black natal coat, still peeling off. 

Growing up Weaner

Weaned pups stay on the beach for six to eight weeks after their mothers leave them. Successful pups have gained enough weight to keep warm in a comfortable coat of blubber. That blubber also supports them during the time they remain on the beach, when they have finished nursing but aren’t yet hunting and eating fish.

They also grow a second set of teeth, molt their baby fur, and develop their oxygen capacity. They practice swimming and holding their breath, so that they will be able to dive and hunt for prey out in the ocean.

Most of the pups get that far, but some don’t. They are the ones lying on local public beaches, among driftwood and rocks that camouflage them, or unprotected on the sand. Most frequent locations for stranded weaners include Morro Bay, Avila Beach, Oceano, Pismo Beach, and San Simeon Cove.

What to do?

It’s never advisable to approach a stranded seal on the beach. You or your dog could catch something, or get bitten. From the seal’s perspective, humans, even well intentioned, are threatening. Stranded weaners are especially vulnerable.

“They are so malnourished and dehydrated that they are very lethargic on beach,” said Giancarlo Rulli, associate director of TMMC public relations. “It’s easy for an off-leash dog or someone concerned to get within a few feet of them, to poke it with a stick to see if it’s alive.”

Finding a weak pup on the beach can be a highlight of a Central Coast visit. Visitors want to do the right thing, but don’t know what to do. Shooing an exhausted pup back into the ocean adds stress to its already weakened condition. It can scare the pup, making the rescue team’s job more difficult.

“Any extra energy they have to use defending themselves from dogs or people detracts from their ability to develop the skills they need to survive in the ocean,” Zink said.

Call for help, The Marine Mammal Center 24-hour hotline, 415-289-7325 (SEAL). Take photos. Find out what the location is. Find beach staff members of other agencies and ask for advice.

“It’s Spring Break. People are heading to the beaches,” said Zink. “Whoever you report it to, State Parks or Friends of the Elephant Seal, they will report it to us.”  

TMMC will send out a team to evaluate the animal and rescue it if necessary. It may just be resting on the beach, not in need of any intervention. Or it may have other injuries that need attention. The goal is to return all marine mammals to their ocean home, strong enough to survive there.

The Marine Mammal Center’s hospital in Sausalito is currently dominated by elephant seal pup patients.

Getting the word out

Finding a stranded seal isn’t something that beachgoers are prepared for. Rulli wants to change that, so that they’ll have the tools they need to report a stranded marine mammal “in their back pocket, on their beach checklist like a towel or sunscreen.”

He’s spreading the word to watersport businesses such as kayak and surf shops and nonprofit organizations engaged with the coast. Restaurants and hotels are other possible locations to support public education on dealing with marine mammals on the beaches, here along the Blue Serengeti.

“It’s a message of hope,” Rulli said, “keeping marine mammals safe.” 

TMMC rescued more than 400 marine mammals in SLO County in 2024.

Successful weaners

 

This pile of elephant seal weaners includes some that still have their birth blackcoats and some that have molted to Silver Bullets.

Even for the strong, healthy weaners, it’s a tough ocean. Only half will survive that first migration. Those that do will return in the fall, then officially considered Young of the Year.

Follow satellite tagged pups at Team Ellie, Cal Poly’s elephant seal research team, led by Associate Professor of Biological Sciences Heather Liwanag.

TMMC Needs a New Site

After 20 years at the Morro Bay site, behind the power plant, TMMC needs to find a new location for its SLO operations. Vistra Corp has other plans for the site. TMMC is asking the public to send any leads on possible commercial properties that could be TMMC’s new SLO County home.

They need enough space for the office and fish kitchen indoors, and outdoors, cages for rescued animals. Storage for various supplies and gear. Convenient access for rescue trucks and vans. Parking for volunteers and staff.

With changing ocean conditions, more marine mammals may need TMMC’s rescue in the future. Currently, warm ocean conditions are fueling a bloom of toxic algae in Southern California, with some sea lions affected by domoic acid toxicity along the Central Coast. During 2024’s DA outbreak, TMMC rescued more than 200 animals within a two-month period.

DA typically affects sea lions rather than elephant seals, due to differences in what they eat. Sea lions feed on the fish that eat the algae and bioaccumulate the toxin.

“We have to change as the ocean is changing,” he said.

TMMC is tapping every agency and real estate broker in the area. If you have an idea, send it directly to the email set up for property suggestions, slo@tmmc.org.

“Our eyes and ears are open,” Rulli said. “We will take any leads.”

Christine Heinrichs is SLO At Large Member of the Monterey Bay National Marine Sanctuary Advisory Council. Her elephant seal column won first place from the National Society of Newspaper Columnists in 2024.

 

 

 

Tribune elephant seal coverage

 The Tribune used AI to compile a list of stories about elephant seals over the past year or so. It's posted here. 

Just Animals on YouTube

 I recorded a YouTube video with Elle and Guy Schwartz. Fun, and another way to tell the world about elephant seals. 

Weaned pups are fat!

 Growing up Elephant Seal

Elephant seal pups are only a month or two old, but they are being weaned, their first big step to independence. They go from birth weight of around 70 pounds to 200 pounds – or more – in that first month.

They are loud! Visitors hear them as soon as they get out of their cars at the Piedras Blancas viewpoint parking lot. Listen for all three distinct calls: the squawking of the pups, the barking of their mothers, and the bellowing of the bulls.

These fat pups are molting their black neonatal coats. They are ready to wean. Their mothers are thin compared to their fat pups. (Chrisine Heinrichs photo)

Weaner pods

Look for them in groups, called pods, on the beach. Weaner pups are easy to recognize. They are fat, even roly-poly. They were born all black, but they shed that black coat in their first molt. Now they are countershaded, light on the belly and dark on the back. Many marine animals have that color pattern, helping camouflage them from their predators.

Weaning is a major transition in elephant seal life. Pups go from gaining weight fast, 200 pounds or more of blubber in a month, to metabolizing that blubber to sustain them for eight to 12 weeks.

No food now

Long fasts, periods of not eating, are a feature of elephant seal life. Their mothers didn’t eat for the month they nursed the pups. Bulls on the beach may not eat for 100 days. This is the pups’ first fast.

As the mothers come to the end of lactation, they are at their thinnest. Their blubber has been metabolized into milk, feeding those chubby weaners. Neither they nor the bulls have had anything to eat since they arrived on the beach.

Females come into estrus as they wean their pups. They are then ready to mate with the bulls. That’s when the bulls get competitive. Earlier battles were over territory. Now, they battle over breeding. 

Look for bulls raising their heads to stare at each other. One or the other will make a move, and one may back off from a fight. It’s called dominance interaction, displacement. From the viewing area, visitors can see which bull is dominant. 

If neither backs down, they’ll battle. The loser may leave the beach entirely, finding another beach to recover. Deaths are rare. Both live to fight, and breed, another day.

Weaners stay out of the way of the adults, who are still in the drama of breeding. Mid-February is the height of the breeding season, but it will continue through March. X-rated.

Swim School

It’s not all sleeping in the sun. Weaners have developmental tasks to accomplish to prepare for their first migration.

Some of that blubber will become muscle as they tussle around the beach. They lose their baby teeth and get their permanent teeth, so they can hunt their own food. The better to eat fish with!

Pups aren’t born with much ability to swim, so this transition time is when they go from beach to ocean. They venture into the surf to practice diving, swimming and holding their breath. Weaned pups learn to hold their breath for around six minutes, some as long as 12 minutes. That will help them stay underwater and dive deep enough to catch food. They are on their own now.

Weaners may be splashing around during the day when visitors see them, but they do most of their practicing at night. Most will leave the beach on their first migration by the end of April.

Watch a video on the Friends of the Elephant Seals YouTube channel.

How to weigh a weaner

Cal Poly’s Team Ellie, led by Associate Professor of Biological Sciences Heather Liwanag, has been weighing weaners at this stage of their lives since 2018.

It takes a team to weigh a weaner! Team Ellie has the equipment and training to get it done, and collect data to understand the elephant seals. (Kenzie Davidson photo under NMFS permit 27514-01)

They mark potential pups to weigh when the pups are about two weeks old. They mark the pups with a letter-number code, using hair dye.

Pups are still nursing at that point. They stay with their mothers until the mother weans them. Weaning is abrupt: the mother simply leaves the pup on the beach, mates with one or more bulls, and swims back into the ocean.

The team keeps track of the now-weaned pups by the dye-marks. As team members re-sight them after they are weaned, and no longer with their mothers, Team Ellie takes their equipment down to the beach to weigh them.

Weaners are generally mild-mannered, but they are wild animals. Dr. Liwanag and Team Ellie members, who have trained to work with these animals, corral them into a canvas bag they had specially designed to be the right size and shape for weaner weighing. It’s snug enough to safely keep their front flippers next to the body and let the back flippers hang out. Except for a hole to breathe through, the weaner’s head is inside the bag. Keeping the eyes covered helps keep the pup calm for the five to ten minutes while it’s being handled. The pup can’t poke its head out.  

“That's where the bitey bits are!” Dr. Liwanag said. A 300-pound weaner can give a nasty bite.

Once contained, the whole weaner, bag and all, is hooked to an industrial scale suspended beneath a 10-foot tripod. Each seal gets two white flipper tags, one in each rear flipper. White tags designate the Piedras Blancas rookery, and double tags indicate that this seal was weighed. Team members measure how long the seal is, and how fat it is, around the underarm girth. These procedures were approved under NMFS permits 22187 and 27514, a California State Parks Scientific Collections Permit, and by the Institutional Animal Care and Use Committee at Cal Poly.

The weaner on the left has its first countershaded coat. The one on the right is molting its black newborn coat. (Kate Riordan photo under NMFS permit 27514-01)

Weaners typically weigh between 220-330 lbs.

Data analysis can increase understanding of how weaner weights relate to overall population trends at Piedras Blancas.

“The population has been fluctuating at the Piedras Blancas colony in recent years,” Dr. Liwanag said. “Comparing weaner weights between years will give us further insight into the health of the population, which may be approaching its maximum population size at this breeding site.”

The Bill & Linda Frost Summer Undergraduate Research Fellowship will support an undergraduate student next summer to work on the data.

Weaners or Weanlings?

Weaned pups may be called either weaners or weanlings. Weaners is an earlier name, perhaps sounds more comic. Weanling is more formal, sounds more scientific. Weaner seems to me to fit these seals, at a roly-poly stage of life.

“I would definitely still call it weaner weighing!” said Dr. Liwanag.

Docent training

If you love those seals, you could be a docent. Hearst San Simeon State Park is recruiting volunteer docents for spring training. Docents become informal educators and wildlife interpreters to visitors to the viewpoint.

The application deadline is March 2. Apply here Meet the State Parks interpreters who lead the program at in person interviews in San Simeon during the first two weeks of March.

The training is professional, and includes reference materials and mentoring. Training includes independent study assignments, two virtual sessions and two in-person sessions. After training, docents are mentored individually three times on site at the bluff.

The time commitment for docents is three or four, three-hour shifts a month. Docents are asked to commit to at least one year of service. Most stay for years. I’ve been doing it since 2007.

Further information here. Call State Park Interpreter Monica Rutherford at (805) 460-8762 with questions.  

Bulls visit other beaches

Bulls visit other beaches

Watch your step! That pile of driftwood may be anelephant seal

Elephant seal bulls are washing up at San Simeon Cove, Washburn beach, and Moonstone Beach in Cambria. Unwary visitors may find that what appears to be driftwood is actually a live seal.

They are subdominant bulls who have been chased out of the breeding beaches. They find refuge on quiet stretches of sand, Bachelor Beaches, where they can rest and heal their battle wounds.

Some call them losers, but I reject that. Any seal that lives long enough to be a contender is a success.

This young bull beached himself at the far north end of Hearst San Simeon beach.

Stay back, and keep dogs on leash

Friends of the Elephant Seal docents expand their presence to Hearst Memorial Beach at San Simeon Cove during the winter months, to help out as Winter Guides. The goal is to protect both sides from each other: avoid any threats to beachgoers, and let the seals sleep without harassment by people or dogs.

The seals are already exhausted and demoralized from losing beach battles with other bulls. 

Two bulls rested at the north end of Hearst Beach in the past week. One slept most of the time. The other went back and forth between the surf and the sand. Perhaps he was considering whether he’s ready to take another try on the breeding beach.

Epic battles 

More pregnant females arrive and give birth at the main rookery at Piedras Blancas every day. The beach is crowded, and bulls’ tempers, competing for breeding dominance, are short. Often, several battles are going on simultaneously on the beach.

Docent Mary Forbes was among the group who witnessed an exceptionally vicious battle last week. After a lengthy battle, one bull was so seriously injured that he was unable to lift his head or move onto the beach. 

Weakened and unable to defend himself, another bull came over to beat on him. He was eventually saved by a wave that surged over him, helping him escape into the ocean.

The first winner, such as he was, retreated to nurse his own facial and nose lacerations. 

Docent Michael O’Bannon, after observing the seals for years, speculates that bulls retreat when their proboscis gets injured.

The soft tissue of the elephant trunk-like proboscis is vulnerable. Bulls bump chests and rip and tear at each other with their teeth. They have big canines.

Beachmasters at the top

They fight for dominance, chasing other bulls away. The most dominant bulls, the beachmasters, have breeding rights with the females, usually a harem of about 30 at Piedras Blancas. Researchers estimate that only about one percent of males born ever get to breed. So there’s a lot at stake.

Females nurse their pups for about a month, then come into estrus, like dogs that come into heat. The mothers who gave birth in December are beginning to become receptive to mating.

It’s a tough time for the bulls. Dominant beachmasters have to be vigilant. Less dominant bulls are ready to challenge their position. When a beachmaster is defeated, he loses all status, drops to the bottom of the hierarchy. He may be one of the bulls that retreat to other beaches.

Beachmasters are subject to “sneaker” bulls, who hang around the fringes of the harem. They seem to camouflage themselves among the mothers, who are busy with their pups. They are attuned to the beachmaster, waiting for his attention to be diverted by a direct challenge. As he galumphs across the beach in battle, the sneaker bull moves forward among the females and tries to mate.

Females typically bellow and complain, but the beachmaster may be too deeply involved in the battle to respond. 

Pups carry on

In the midst of this conflict, pups need to nurse to gain weight and grow. They may get separated from their mothers. They may starve if they can’t find each other and reunite. Pups separated from their mothers may find another mother willing to let them nurse. About 80 percent of pups nurse on more than one mother before they are weaned.

Not all pups survive, and mothers sometimes fight over a pup. O’Bannon witnessed two mothers fighting over a pup. Both mothers tried to keep the pup, picking it up with their teeth to keep it away from the other.

No Solomon appeared to mediate their struggle, but the pup survived and was later settled and nursing.

A Seal’s Life

Although conflict and chaos churn across the beach, the seals find enough peace to accomplish their birth and mating season. It’s an exciting time for visitors to view the seals, and enjoy occasional closer encounters on local beaches. 

High tides and surf the weekend of January 10-13 will add more stress. The high-water line will crowd mothers and pups into a smaller area. Waves threaten to wash pups out to sea. Every day brings challenges.

Take lots of pictures, and bring home those stories to tell.

 

Welcome, Winter! The First Pup of the Piedras Blancas elephant seal breeding season

Welcome, Winter!

The First Pup of the Piedras Blancas elephant sealbreeding season

The first elephant seal pup of the breeding season appeared on the south beach of the Piedras Blancas viewpoint on Sunday morning, December 8. Sharp-eyed Kris Clifford noticed the pup on the Friends of the Elephant Seal webcam. https://elephantseal.org/

Mother and pup are resting comfortably on the beach. A substantial bull stood guard some distance away. He bellowed frequently Monday afternoon. A few other bulls slept on the beach in the area, presumably aware of the newcomer and its mother.

That dark dot in the center of the photo.

Naming rights

FES Docent Bill Michelson named the pup Winter. He had the privilege of naming because he won the First Pup contest. It’s an informal lottery, to guess the date when the first pup will arrive. Michelson won, earning the naming privilege and bragging rights for the season.

Harbinger of the season

Winter is the first of over 5,000 pups that will be born between now and February at the Piedras Blancas rookery, which extends from the light station to about a mile south of the viewpoint. Mothers will continue to arrive, one by one. They settle on the beach for a few days and then give birth to their pups.

Seeing a pup born is exciting. Many pups are born at night, as Winter may have been, but daytime births are common.

Look for a female seal digging out a “saddle” by tossing a lot of sand on both sides. That sometimes indicates that she will soon give birth.

Nothing is certain, though. As soon as you’re paying attention to one seal, another down the beach will squirt out a pup.

Gull announcements

As soon as a pup is born, gulls screetch and swoop around to consume the afterbirth. They are the beach clean-up crew. If you miss seeing the moment of birth, you can follow them to see the newborn and mother make their first barks and sniffs to each other.

Pups and their mothers recognize each other by their vocalizations and their scent. That gets established within the first couple of days of life. It’s important, because a pup separated from its mother may starve and die. Maternal separation is the most common cause of pup death.

While all pups are vulnerable, most pups nurse on more than one mother at some time. Later, when the beach is crowded with mothers and pups, some mothers may nurse more than one pup.

Not every pup survives, although over 90 percent of the pups at Piedras Blancas do. A mother whose pup dies may let other pups nurse, or may adopt another pup.

With so many mothers and pups on the beach, any mother and pup may get confused.

One pup per mother

Each mother has only a single pup, about three feet long and weighing about 75 pounds. Mothers nurse the pups for about a month. They pup gains weight rapidly, up to about 300 pounds. The mothers stay with the pup the entire time. They don’t leave the pup to feed in the ocean, so they lose a lot of weight, about a third of their body weight.

It’s good to see Winter’s mother looking fat. She’ll need it.

Above high tide line

Winter is in a good position on the beach, well above high tide line. That’s an important consideration, because King Tides, the highest tides of the year, will reach up the beach this weekend, December 13-15.

Winter can’t swim much yet, and hasn’t nursed long enough to gain much blubber. Without blubber to stay warm, and able only to paddle a little in the water, pups can drown.

Mothers may give birth at low tide, not realizing that their pups may be at risk later. Most of the north beach at the Piedras Blancas viewpoint is inundated with waves at high tide. Some pups born in the few areas behind rocks are safe, but any born on the open sand may be washed away.

Share King Tide photos

You can take photos and submit them to the California King Tides Project. Think about taking photos in areas that are subject to flooding and erosion, and of places where high water levels can be gauged against familiar landmarks such as cliffs, rocks, roads, buildings, bridge supports, sea walls, staircases, and piers.

Taking and sharing photos documents the changes in ocean level and how those changes are affecting the coastline.