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.

Entangled seal eludes help

 He resisted and escaped from those who would free him

In October, Friends of the Elephant Seal docents saw a seal with an entanglement around his neck on the beach at Piedras Blancas. He was at the far south end, difficult to observe. But that plastic was cutting into his neck.

“It’s always really tough to see these cases come up in the rookery,” said Aliah Meza, operations manager for San Luis Obispo Operations in Morro Bay.

Response begins

The Marine Mammal Center responded by sending observers, to determine how to help this deal in distress. When he moved to the north beach in the first week of November, observers got a better look. It was a plastic packing strap.

On Monday, November 4, the seal was easily visible on the north beach. I got some good photos, and encouraged a visitor with a long-lens camera to take some photos and submit them to TMMC.

A young family visiting, with two young daughters, were concerned abut the entanglement. The father offered to scale the fence and go down and cut it off.

I cautioned that it’s more difficult than it looks. He’s a pretty big seal. TMMC estimated he weighs around 260-330 pounds. It’s also illegal. Better to wait for the trained rescuers.

But I assured them that everyone at the bluff is concerned, and will take action to help that seal.

Better information makes better plans

Clearer photos of the entanglement help TMMC staff to make a plan that stands the best chance of success. The TMMC team went out with their own camera, to assess the beach surroundings.

“Once we got those details, we wrote up our plan,” Meza said. The plan was approved by the National Oceanic and Atmospheric Administration, giving them permission to go onto the beach and attempt the rescue from this human-caused threat.

Photo by Laurie Miller, c The Marine Mammal Center

Approaching a seal to remove an entanglement is tricky. First, it must be safe for the team members to make an approach. It has to consider the animal’s safety as well as the people’s safety.

“You never know what a wild animal is going to do,” she said.

Fall juvenile haul-out is a good time of year for a rescue. Fewer animals are on the beach, and those that are there are smaller, younger seals. No aggressive bulls.

“That minimizes the potential risk to other animals,” she said. “We have to consider all the contingencies that can happen.

Photo by Laurie Miller, c The Marine Mammal Center

The plan takes shape

The team was ready to go on Wednesday, November 6. By then, the seal had moved back to the south beach.

“Circumstances change daily, hour to hour,” she said. “We had a detailed plan for a different location. We had to think on our feet. Our field response team is very well trained.”

The team included three rescuers on the beach and others on the bluff, to monitor safety and take notes and photos.

They planned to confine the seal behind herding boards, then use a hook knife attached to a pole to cut the strap. They wouldn’t have to sedate the seal to immobilize him. That gets more complicated, requiring a veterinarian to oversee the process, and monitoring until the seal is fully awake.

“The animal is so large, we can’t put it in a carrier and remove it to our hospital,” she said.

It only takes one cut. But plastic is tough, and this seal was having none of it.

“He was pretty alert,” she said. “He was too active, and returned to the ocean.”

They’ll try again

Rescue attempts often don’t succeed on the first try. The plan for this seal is in place with NOAA approval, so the TMMC team is ready to go if anyone reports him on the beach.

Entangled seals can be fdifficult to identify from the bluff. Check the photo to see where he is.

If you see him, call 415-289-7325 and give the reference number 3348 to identify this seal.

As soon as the seal comes back to the beach, they’ll try again to remove the strap, before it causes permanent damage to organs. As it is, this seal will have a scar from it forever.

“These entanglements show the interconnectedness of humans and oceans,” Meza said. “It’s important for us to prevent single use plastics from entering the ocean.”

TMMC has more information about ocean trash on its website, https://www.marinemammalcenter.org/science-conservation/conservation/ocean-trash

 

 

 

 

All Hail, Returning Heroes!

 
When will the first bull arrive?

Friends of the Elephant Seal holds a contest every year, to guess when the first bull will arrive for the breeding season. Submit your guess here. Enter the First Bull contest here! (mailchi.mp)

The prize is the satisfaction of guessing right, and being praised by FES members and elephant seal admirers. Which is the main point, and the most fun!

Surfing in

The arrival is typically quiet, as a bull surfs in on a wave. He’ll galumph a few times onto the beach, then slump down. His huge body, supported by buoyancy in the water, now feels the weight of gravity. Transition to living on land is difficult.

The remaining seals on the beach are juveniles who haven’t yet departed after their fall haul-out. The arrival of mature bulls usually clears nearly all of them off the beach.

The juveniles have rested on the beach since September. Time now for them to go on their second migration of the year. They will forage and grow bigger, become more mature. Females may enter the breeding population, getting pregnant for the first time. Young males will return next year, with the oldest joining the mature bulls and taking a place in the dominance hierarchy.

Bulls bellow

After the shock of arriving on the beach, bulls announce themselves. They are among the loudest animals on earth. They need to be. A bull needs his threat vocalization, also called a clap-threat or a belch-roar, to intimidate opponents far and wide. The threat can carry around 75 feet, over the background noise of wind and waves. I’ve heard bellows echoing farther than that, an eerie call as darkness covers the beach. At a recent evening event at the Piedras Blancas light station, the elephant seal calls added to the sense of being in a strange other world.

A bull will raise himself up, his chest shield thrust forward, holding himself up on his flippers, open his mouth and let ‘er rip. Each bull has an individual call, identifying him to other bulls. If they’ve fought before, no need to fight again. They establish themselves in the dominance hierarchy. They can remember who beat who for years.

As the elephant seals have increased in numbers, bulls’ calls have become more complex. This may have happened because of the larger numbers, and the need to identify themselves as individuals.

Dominance

Only the dominant bulls, the beachmasters, get to breed, so there’s a lot at stake. By the peak of the breeding season in January and February, around 235 beachmasters will reign over harems of 30-40 females at Piedras Blancas.

The bulls are at their largest physical bulk now, after months of feeding along the North American continental shelf. They’ll need it to get through to March without eating.

Bulls stop feeding when they leave their foraging grounds and head south for the breeding beaches. They’ve been eating fish and squid, gaining as much as 28 pounds a day, since they left the Central Coast in August and September. They need enough blubber to survive 100 days or more, to the end of the breeding season. They are huge now, but will get thin over the coming months.

Look for long noses and big pink chest shields on massive bodies. They surf out onto the sand, their massive weight now subject to gravity instead of supported by water. Welcome to life on land!

Every bull on the beach is a survivor in a tough world. Only about one percent of male pups born reach breeding age. Surviving is essential, and those tough enough and lucky enough will have two to four good years to breed.

Surviving isn’t enough to guarantee breeding, though. They jockey for dominance and breeding rights. Two thirds of the bulls, the less dominant ones, don’t get to breed at all.

Why they fight

Early arrivals find enough beach to separate them, but they fight to establish the dominance hierarchy. It’s relatively stable, but always subject to change. As new bulls arrive, and bulls move from beach to beach, any beachmaster may be defeated.

The dominance hierarchy dictates breeding rights. Males fight for dominance and to defend their harem of females. They arrive looking for a fight and it only gets worse.

Size is an advantage, but not the only factor.

The alpha bull, the beachmaster, is frequently challenged by other bulls. He can lose a battle and lose his place in the dominance hierarchy. A deposed bull may fall so low in the dominance hierarchy that he loses all breeding rights that season.

Beachmasters are vigilant about chasing other bulls away from the harem, but it’s a constant challenge. All bulls are focused on mating, regardless of their status in the beach hierarchy. Lower ranking bulls sneak around the harem and try to mate with females. They sometimes get away with it.

Fights can be brief encounters, an exchange of threats, or they can be violent struggles that go on for half an hour or more. Bulls may start fighting on the beach and continue fighting in the water.

They rear up and rip and tear at each other. The chest shield provides some protection, a calloused area that bleeds but is not life-threatening. Wounds can be severe, but immediate death is rare. Some bulls may escape to the sea and die of their wounds later.

King Tides

King Tides are the highest tides of the year. They are predictable, happening when the sun, moon, and Earth align to exert the greatest gravitational pull on the ocean. This year they will occur on the mornings of November 15-17 and December 13-15.

California Coastal Commission invites the public to submit photos that illustrate how far the water reaches on those tides. Photos must be dated and timed, taken as close to high tide time as possible.

Check out the places that have been photographed in the past. https://coastalcomm.maps.arcgis.com/apps/MapSeries/index.html?appid=f5652282f2c84e3194a8f1e4af9e15ba  Plan your photography for those and locations that haven’t been photographed on those dates. There are gaps north of the Piedras Blancas elephant seal viewpoint (one of my photos from last year); between Cambria and Morro Bay; and south of Los Osos. Think about areas that are subject to flooding and erosion, and places where high water levels are obvious against familiar landmarks such as cliffs, rocks, roads, buildings, bridge supports, sea walls, staircases, and piers. https://www.coastal.ca.gov/kingtides/ 

Visiting the Viewpoint

The arrival of the full-grown bulls heralds the most exciting season at the rookery. The parking lot has been maintained in good condition. Friends of the Elephant Seal docents are available every day to answer questions.

Check the live webcam to see what’s happening on the beach. https://elephantseal.org/live-view/  Maybe today’s the day to drive up Highway 1 to see the seals. Highway 1 is open only as far north as Lucia Lodge. It remains closed due to the Regent Slide between Lucia Lodge and Esalen Institute.

Bring your camera.  Always open, always free. One of the spectacular advantages of California’s Central Coast.

 

Fall Haul-Out

 

Fat seals rest, safe on the beach

In the fall, young seals get the beach to themselves. Away from the bellicose bulls and the touchy adult females, they rest on the beach. It’s Juvenile Haul-Out.

It’s the interregnum between the bull dominance, on the beach to molt during the summer, and returning for the winter breeding season. Juveniles left the beach in the spring, after they joined the adult females on the beach to molt their skin. The young seals have been at sea since May, feeding and adding blubber. They are fat now, their smooth skins filled out.

They will fill the beach until late November, when the bulls start arriving for the breeding season. Not all the seals are on the beach the entire time. They come and go. It’s a good time to see seals of various sizes and levels of development. They are too young to have a full trunk-like nose, but some have the beginnings of one. They are all elephant seals, on their way to maturity.

This young bull is about six years old, judging from the size of his proboscis (nose).

Survival Success

Every seal on the beach is winning the survival marathon. Elephant seals are in constant danger of being eaten by white sharks and orcas.

The smallest are the Young of the Year, last year’s pups returning from their first migration. Of the 90-95 percent that survive to be weaned and enter the ocean for their first four- to six-month migration, less than half survive to return to the beach in the fall. They may be no fatter than when they left, and may have even lost weight, although they may have grown a little longer.

The challenges are great. Each seal must learn, on its own, to hunt food in the dark, cold ocean at 1,000 feet and deeper. Starting out, they have so much blubber that they are buoyant. It takes energy to swim down to find the fish and squid that are their prey. As they swim, they develop more muscle.

Although they practiced holding their breath and diving before they left the beach, out in the ocean they have to hold their breath longer and dive deeper. As they migrate, they get better at it. By the time they are two years old and have made four migrations, they are as good as mature seals.

Evading predators

They have evaded their predators, swimming back to the surface only briefly, through the “lightscape of fear,” to catch a short breath and then dive down again. Rising to the surface though the range of their white shark and orca predators is the most dangerous time for them.

Young seals stay longer at the surface than adult seals. They may need to take time to process the food they caught while they were diving. Longer time at the surface may have accounted for the batteries running out on Monarch, the Cal Poly seal who swam all the way to the Aleutians last year on her first migration. The research team is adjusting the batteries they use for the coming year to account for the greater time the young tagged seals spend at the surface.

Arriving on the beach is triumph enough. Those survivors include seals that will someday breed successfully.

Larger seals are relatively older. I saw some six-year-old males this week, estimating by the size of the nose. Bulls are fully mature at eight years old, so these have some growing and maturing to do before they join the breeding population.

More of the seals on the beach are male than female. Females mature earlier than males, with most having their first pup by the time they are four years old.  

Migration

Seals probably rely on a suite of senses to find their way from California north to Alaska and back again, which UC Santa Cruz researcher Roxanne Beltran describes as “astonishing navigational feats.”  They have some sense of direction, even when they are under water. They likely use some combination of geomagnetic, celestial, acoustic, or olfactory cues to find their way.

Young seals are adjusting their migratory schedule. As they mature, instead of returning in the fall, they will return to the beach in December and January, for the breeding season. As juveniles, they avoid the hectic threats of that season by hauling out in the autumn months.

Sharks

These fat young elephant seals attract white sharks. White Sharks migrate toward the California coast from as far away as Hawaii. The Farallon Islands, Tomales Bay and Monterey Bay are more active feeding sites, but shark-bitten elephant seals are often on the beach at Piedras Blancas.

Scars show severe wounds that the seals somehow survive. Blubber doesn’t have a rich blood supply, and I like to think that it doesn’t have many nerves, either.

This seal survived a devastating attack. 

The sharks store up oil in their livers as they feed on the elephant seals. Sharks will take an elephant seal any time throughout the seals’ range, but juveniles are especially preyed upon in the fall in the Farallon Islands. Sharks attack full-grown bulls around Año Nuevo in December and January.

A good blubber meal gets the sharks through the long winter migration, to the White Shark Café halfway between California and Hawaii. Scientists still aren’t sure why the sharks converge there.

Follow elephant seal and shark migrations at https://gtopp.org/ . Or buy a shark or elephant seal tracking bracelet at the Friends of the Elephant Seal Visitor Center in San Simeon. For $20, you can follow an individual shark or seal on a phone or computer. A docent reported that a 14-foot shark nicknamed Battle Axe was swimming offshore this week.

Digital technology has changed wildlife research. Without it, we would not know where the seals and sharks migrate and how deep they dive.

 

Seal Olympians

 Seal Olympians

Three seals’ long migrations featured in new exhibit

The world’s attention may be on human athletes at the Olympics in Paris, but elephant seal observers are celebrating seal athletes. A new exhibit at the Friends of the Elephant Seal Visitor Center in San Simeon puts three seals on the metaphorical platform, for migrations of more than 6,000 miles over seven months.

The exhibit characterizes them as three human swim champions: Diana after Diana Nyad, Katie after Katie Ledecky, and Trudy after Gertrude Ederle. Diana Nyad is a long-distance open water swimmer who swam from Cuba to Florida in 2013, through stinging jellyfish and sharks. Katie Ledecky is a competitive swimmer who has won seven Olympic gold medals (2012, 2016, and 2020) and 21 world championships. Gertrude Ederle was the first woman to swim the English Channel in 1926.

Kathy Curtis photo

Two annual migrations

Female elephant seals have the advantage over human swimmers, spending 10 months of the year in the ocean. They swim two annual migrations, a short one and a long one. The short migration, about ten weeks, comes after they wean their pups in the early spring. Elephant seal mothers don’t eat while they are nursing their pups, so they lose about a third of their body weight. It’s physiologically draining.

By the time the pup is big enough to wean, the mother is thin. She needs to regain blubber. She leaves the beach in February or March, returning in April or May. At that time, she stays on the beach for four or five weeks to molt her skin. When she returns to the ocean, it’s for her long migration, seven to eight months. The next time she comes out of the water, it will be to have her pup in January.

What are they doing out there?

All elephant seal females spend those months feeding in the open waters of the North Pacific. But some go far west, 3,200 miles west, to feed. Roxanne Beltran’s research team at University of California Santa Cruz documented the long migrations by tagging female seals. One, nicknamed Diana, was tagged twice, and made the same journey twice.

Female elephant seals have to forage almost constantly to gain weight and support the developing pup. Most forage on small fish in the mesopelagic layer, although about 15 percent dive down to forage on the ocean floor along the continental shelf or at seamounts.

They have to gain enough weight to support them in their travels, and to develop a pup and then carry them through nursing the pup for a month. That’s a lot of blubber.

They share the mesopelagic layer with a few other large species: sperm whales, beaked whales, blue sharks, and salmon sharks. Scientists don’t know much about how they all share this ocean resource.

The New York Times recently published an OpEd on the Ocean Twilight Zone.

Season statistics

The exhibit gives these athletes’ stats on their migrations: How far they went, how long they were at sea, how much weight they gained. With one exception, they each did it while pregnant, having a pup every year.

Trudy and Diana spent 223 days at sea. Katie made her trip, to a point 3,436 miles west, and back in only 185 days.

Diana gained the most weight, 448 lbs.  Katie gained 279 lbs. and Trudy gained 293 lbs.

What’s out there?

They all went to the same general location, but probably didn’t interact with each other. Seals are solitary.

“Although there are a lot of elephant seals, maybe 240,000 total, they are foraging in a HUGE volume of the ocean,” Beltran wrote in an email. “so they likely don't encounter each other often.”

Perfect timing

The tricky part is heading back to the beach in time to give birth to the pup. They have to find their way around the open ocean, catch and eat enough fish to gain weight and support the developing pup, and then turn around and find their way to the beach to have that pup. They give birth within five days of returning to the beach.

Beltran’s research team found that the seals have a “map sense” that allows them to know how far they are from that home beach, and how to manage their time, at about 100 miles a day, to get back.

“We found that the seals’ abilities to adjust the timing of their return migration is based on the perception of space and time, which further elucidates the mechanisms behind their astonishing navigational feats,” the academic paper’s summary states.

No one yet knows how they do it. Geomagnetic, celestial, acoustic, or olfactory senses may be involved.

For now, observers use electronic tagging to learn what the seals are doing, and welcome them back to the beach when they arrive in January, in time to have their pups.

August seal viewing

The bulls, fully mature ones and younger ones, are on the beach at Piedras Blancas. They are molting their skin, the annual shedding. FES docents have samples of shed skin for visitors to handle.

Bulls are generally quiet at this time. With no females to fight over, they spend their days resting on the sand.

Monarch's first migration

Monarch’s long journey

One pup returns from a year at sea

Researchers don’t often put electronic tags on elephant seal pups. At more than $3,000 per satellite tag, losses are just too high to risk expensive technology. But in one case, it paid off big time. One tagged pup not only survived, she returned with new and exciting data. 

Photo taken under NMFS permit 27514.

The first migration

Elephant seals are migratory, swimming north along the coastline as far as Alaska and out into the northern Pacific. After pups are weaned, they remain on the beach for a month or so, building up their breath-holding and swimming skills. But they have nothing to eat after their mothers leave them. They live on the blubber they gained while they were nursing. Weaned pups make their first migration alone, without adult guidance. They leave the beach in the spring, and those that survive return in the fall.

Although pups haven’t been tracked on that first migration, the accepted wisdom was that they didn’t get as far as adults, to Alaska, on that first migration. Cal Poly Associate Professor  Heather Liwanag’s research set out to see how far they did go. They learned that while most don’t get that far, at least one did.

Pups tagged at Vandenberg and San Nicolas

Katie Saenger, one of Professor Liwanag’s master's students, tagged five pups at the Vandenberg Space Force Base beach and five pups on San Nicolas Island in April 2023. Their electronic tags allowed the researchers to follow the pups in real time.

Photo taken under NMFS permit 27514.

The researchers chose nicknames for the seals from local wildlife: Frog, Plover, Goby. Monarch’s name turned out to be especially apt. Monarch butterflies are also long-distance migrators.

Tracking that first migration

Nine of the pups stayed conservatively close, migrating along the California-Mexico coast. The team retrieved a device from one at King Range National Conservation Area, near Cape Mendocino in Northern California, and one from Año  Nuevo, north of Santa Cruz. Another was tracked to San Francisco Bay, but the beach he hauled out on in the Farallon Islands was inaccessible to humans.

One of the Vandenberg seals, Monarch, swam north and kept on going. 

Team members and other elephant seal observers watched her progress. Without guidance, pups somehow find their way. They don’t swim across the surface. They dive down and come back up, making forward progress. Females like Monarch may feed along the way, snapping up small fish.

Monarch swims, and swims

Watchers were excited to follow the signals coming from Monarch’s tracking device. She was doing so great! Going farther than previous research led them to believe pups would travel. Go, Monarch!

Her up-and-down zig-zagging indicated that she was finding food in those cold Alaskan waters. Out to the edges of the Aleutian Islands, nearly to Russia.

On October 5, 2023, after six months at sea, she turned south and headed for California. All seemed fine until October 26. Monarch’s transmitter went silent. The bad news for seal pups is, that usually means they met their fate in the jaws of a white shark. Thus goes the cycle of ocean life.

But it wasn’t. The transmitter's battery had failed, but Monarch hadn’t. She was still swimming back. A scientist taking a bird survey saw her on May 12, hale and hearty.

It’s Monarch!

Julie Howar, Senior Marine Ecologist and GIS Specialist from Point Blue Conservation, was performing bird surveys at Vandenberg when she saw two elephant seals wearing transmitters on their heads on the beach. One was this year’s weanling, Aurora, who had not yet left the beach after being tagged in April 2024. The other was a juvenile.

Photo by Julie Howar.

Identifying elephant seals is a challenge. Because they molt their skin every year, dyed marks fall away with the skin. This young seal had no dye marks, but she had a flipper tag that was partially visible. Dr. Howar used her spotting scope to take a photo. She was able to read a couple of digits on the seal’s flipper tag. She reported the sighting to Liwanag.

It was Monarch!

“It was amazing that Julie knew what to look for and reached out to me!” Liwanag said.

Surviving the first migration is significant, since only about half of the pups do. They usually gain little, if any, weight. Monarch went a step better: she gained 73 pounds. The fishing in Alaska was good.

“We were so excited when we figured out it was her,” said Liwanag. “She is the first seal to demonstrate that weanlings can go as far as Alaska, which we did not expect.”

Retrieving the data collection devices

Left to right: Molly Murphy (Cal Poly graduate student), Katie Saenger (Cal Poly graduate student), Kate Riordan (Cal Poly MS graduate), Dr. Heather Harris (TMMC), Liz Eby (TMMC), Dr. Heather Liwanag (Cal Poly), Lauren Campbell (TMMC), Elise Fiskum (Cal Poly undergraduate), Kenzie Davidson (Cal Poly graduate student), Rhys Evans (Biologist, Vandenberg Space Force Base), Jenna Camargo (Cal Poly undergraduate). Photo by Dave Clendenen.

The Cal Poly researchers pulled together a team to retrieve the devices on Monarch’s head and back. Master’s student Katie Saenger led the team, since Monarch is part of her thesis project. Liwanag and graduate student Maria Lopez-Neri joined her, along with veterinarian Heather Harris and veterinary technician Lauren Campbell from The Marine Mammal Center, and Vandenberg biologists Rhys Evans, Nick Todd, and Zia Walton.

“Accessing the beach at Vandenberg is always an adventure,” Liwanag said.

Todd is an experienced climber, skills he uses as an ornithologist specializing in falcons. He guided the group in setting up a rope to help them climb the bluff to the beach.

“The last part is especially steep, and it's best to move down backward -- not quite rappelling, but definitely not just hiking,” Liwanag said. “It is a challenge to get our team and all our gear down the hill (and back up!), especially with our heavy weighing gear.”

Photo by Molly Murphy

Weighing a seal involves a tripod with a scale. The seal is lifted in a tarp to be weighed. Nothing involving elephant seals is easy.

On the beach with the seal, The Marine Mammal Center veterinary team, Harris and Campbell, administered the sedative and monitored the seal while she was sedated during the tag removal. The amount of sedative needed is based on the seal’s weight. Monarch was cooperative enough that the team could weigh her before they gave her the injection. A safe dose calms the animal to allow researchers to handle her safely, without endangering the seal. It’s a delicate balance.

The zip ties were cut. Success! Devices in hand.

Analyzing Monarch’s data

Back at the lab, they downloaded the data. Preliminary results show that Monarch dove as deeply as 600m (2,000 feet), with many dives between 400 (1,300 feet) and 500m (1,600 feet) deep.

“These are impressive dive depths for a young seal pup!” Liwanag said.

Saenger’s master’s thesis project focuses on that first foraging migration of newly weaned northern elephant seals. The paths reported by the tracking devices map out where they travel, which can then be related to ocean factors that adult seals are known to use to navigate, such as sea surface temperature, the ocean floor, including the Alaskan coastal shelf and the seamounts along her return trip, and productivity.

“We simply don't know where these seals go on their very first migration, or how they decide where to go,” said Liwanag.

Other possible influences are whether the seal is born in a new or an established rookery, and whether they are male or female. Adult female and male seals migrate to different places, with different foraging strategies.

“We know the adults have very different migration patterns between males and females, but we expect that these differences may not be as pronounced at this age.” Liwanag said. “So far, we see that there is a lot of individual variation in migration patterns. This makes sense, because the seals have to find their own way with no instruction from anyone. They don't learn from their mom, and they don't travel together.”

Asleep on the beach

After removing the devices, the team watched over Monarch until she recovered from the sedative.

“Monarch moved back near her original napping spot and seemed to be doing just fine,” Liwanag said.

Welcome back, Monarch.

Activities conducted and photos taken under NMFS permits 22187-04 and 27514.

Satellite and VHF tags

The pups get satellite and Very High Frequency (VHF) radio transmitter tags.

The satellite tag is zip-tied to a polyester mesh glued to the seal’s head with marine epoxy.

The satellite tag on her head sends signals to the satellites when the seal comes up for a breath and her head is out of the water. The batteries on Monarch, and other seals in that 2023 cohort, ran out of juice and stopped transmitting. These young seals may be spending more time at the surface than adult seals, running the batteries down. The researchers adjusted for that possibility in 2024 by programming tags to transmit less frequently, extending battery life.

A VHF radio transmitter is zip-tied to polyester mesh on the seal’s back.

“We use that to home in on the exact location on the beach,” Liwanag said.  “We only want to hear that signal when the seal is completely hauled out.”

The polyester mesh patches will fall away as Monarch molts her skin.

“That’s why we hustled down there to retrieve her tags as soon as we could,” Liwanag said. “She was in the process of molting off those patches, and we were worried that the tide might take the tags away if she molted them onto the beach.”