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.
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