Monday, August 31, 2015


A good day for birds at the bluff. California gulls as usual, enjoying the company of Heerman's Gulls.
Heerman's Gulls are pretty, with their dark gray plumage and red bills. They migrate up from Mexico at this time of year.
Elegant Terns accompany them. That crest of feathers gives them a jaunty, almost punk look.  

Friday, August 28, 2015

Sleeping giants

Summer vacation draws crowds of visitors to Piedras Blancas to see the elephant seals. In August, adult and subadult male seals are on the beach.

Seals are on the beach year round, but as migratory animals with an annual cycle, they are always coming and going. There are fewer seals on the beach in summer than other times of the year.

The seals come and go individually. They don’t live in a group in the ocean, so they make their way back to Piedras Blancas on their own schedules. A large male may lift his head out to announce himself, perhaps inviting a sparring match. Fighting isn’t serious at this time of year, with no females around. Male seals are usually willing to take on a challenger.

These are the biggest, the grand bull seals, weighing as much as two and a half tons. This is a seal worth seeing. Their pendulous trunk-like noses, technically proboscis, give them their name.

They come to the beach to molt their skin at this time of year. Circulation to the hair follicles of the old skin stops, and it simply peels off. Blood flows to the new skin underneath. Research on harbor seals using thermal images show that the new skin gets much warmer as blood flows to it to help it grow.

The seals’ short, stubbly fur looks nearly black when it’s wet. As the sun dries it, it takes on a lighter brown color. Elephant seals weren’t hunted for their fur, the way otters and fur seals were. They were hunted for their blubber, used for lighting oil and machinery lubricant. The invention of electric lighting and lubrication alternatives from petroleum helped save them.

Sea otters, whose fur has as many as a million strands per square inch, rely on their fur for warmth. Those long, waterproof hairs and soft underfur trap air, keeping their skin dry and insulating them against the cold water. Sea otters are creatures of the surface, diving down to the bottom in shallow waters, as far as they can go in one to four minutes. Elephant seals are creatures of the deep. At 1,000 feet and deeper, the pressure would squeeze any trapped air out of their fur. As in so many other ways, elephant seals are adapted to their environment and the niche they occupy.

Males being naturally competitive, they may spar with each other, on the beach or in the water. Mostly, they sleep. Awake or asleep, they may hold their breath for ten or fifteen minutes, apnea. That’s normal for them. As deep divers, they are accustomed to holding their breath. Typical dives are 20 to 30 minutes, but dives of an hour are typical, and dives over two hours long have been reported. When they are on land, each breath expends moisture and energy. Taking fewer breaths, called sleep apnea, is a problem in humans but for elephant seals on land, it conserves energy.

Watch one or two individual seals to see how long they go between breaths. Ask a blue-jacketed docent to show you a sample of shed skin. They are on duty every day.

Tuesday, August 18, 2015

Humpback whales join the seals

John FitzRandolph reports on a young humpback whale in San Simeon Cove:

This story could develop into the North Coast’s marine mammal mystery of the year, and it could prove to be among the most treasured wildlife encounters witnessed here in many years.
For 24 consecutive days (as of Tuesday, Aug. 4), a juvenile humpback whale has been dining on anchovies, sardines and other small bait fish in the San Simeon Cove.

Why has this whale lingered for so many days in the Cove? If there are ample schools of bait fish in the Cove, why aren’t there other whales feeding there as well — as there have been in recent weeks?

Read the rest of his story here.

So this story about humpback whale songs caught my attention: NPR reports:

Read more here:
Humpback whales don't just sing songs — they compose with the whales around them, singing a song that evolves over time. Scientists didn't know that until they started recording whale sounds in the 1960s and spent years listening. The evolution of this "culture of listening" among researchers is the focus of Morning Edition's weekly summer series, Close Listening: Decoding Nature Through Sound.
Katy Payne, a researcher in acoustic biology at the Cornell Lab of Ornithology, and her husband, Roger, were the first scientists to realize that the intricate and eerie calls of some humpback whales are actually songs. At a recent visit with Katy in a Cornell sound studio, we played this archived recording of the first whale they ever heard, and she recognized it right away:
"It's the voice of a male humpback whale off shore of Bermuda, in 1964," Katy explained. "It was recorded by a Navy engineer."

Read or listen to the rest of the story here.  

Wednesday, August 12, 2015

Hawaiian Monk Seals

We don't see these rare and endangered seals in California, but their plight concerns us all. John Platt writes about them on Motherboard:

Fans of “The Walking Dead” know it doesn’t take much to start a species-ending apocalypse.

A bite. A scratch. A sneeze. One opportunity to pass a pathogen to someone else and the race toward extinction begins.

That fictional scenario is scary enough, but for some species the reality is even more terrifying—and more likely to happen sometime in the not-so-distant future.

Take the Hawaiian monk seal. Once hunted into near-extinction for their meat and fur in the 19th century, only a few hundred monk seals remained when they were finally protected under the Endangered Species Act in 1976. Intense conservation efforts increased that population to about 1,500 in the 1980s, but the seals still face a precarious recovery. The animals frequently die from entanglement with fishing gear and their population has shrunk to about 1,100 today.

Hawaiian Monk seal mother and pup. NOAA photo
The seals still carry scars from that close call with extinction. The species has the lowest genetic diversity of any of the world’s seal species, which means they have a similarly low resistance to disease. The introduction of a virus to the ecosystem could easily wipe out the species, said Charles Littnan, lead scientist for the National Oceanic and Atmospheric Administration’s Hawaiian Monk Seal Research Program.

This is not a theoretical danger.

Around the world, seals and other marine species have experienced several mass die-offs after exposure to morbilliviruses, a group of diseases that include canine distemper and the measles.

“The destructive force of a disease is comparable to nothing,” Littnan said. “There is no reason to believe that if morbillivirus comes and gets into monk seals, and this program isn’t in place, that it will be anything less than catastrophic.”

Read the rest of the story here.

Thursday, July 9, 2015

Green Tie

This could be Green Tie, a seal who was entangled in green plastic packing strip back in 2011. He was energetically tussling with other seals in the surf. The scar looks deep, so he is probably not entangled any more.

Welcome back, Green Tie!

Saturday, June 27, 2015

Good-bye Girls

From my column in The Cambrian:

The crowds thin out in June. Not the people, the seals. The beach that was covered with seals now shows plenty of sand between them. Fewer but larger, the subadult males are on the beach to molt their skin in June and July. The biggest adult males will return in July and August.

Subadult means that they are growing that distinctive elephant seal nose (technically it’s a
proboscis, a long nose), but aren’t fully mature. Their skin peels off once a year, and they spend four to six weeks on the beach looking terrible.
A six-year-old faces off with a seven-year-old
Tap a Friends of the Elephant Seal docent — a guide in a blue jacket — and ask to touch some of the shed skin. They carry samples to share with the public.

The beach is less crowded than the crush of May, when the adult females and the juvenile seals of both sexes rested on the beach for their molt.
There's space between seals in June
 They have now left the beach, swimming off  in their new skin. The juveniles will return in September for their fall rest, but the females won’t come back until January, when they return to have pups. They have set off for an 8-month migration, to eat and grow pups.

They’ll be finding fish and squid to eat in deep waters. Wildlife habitat on land is easy to understand. It’s the woods, the plains, the fields. In the ocean, it’s not so obvious. It’s complex and three-dimensional, with zones of different temperature, density and salinity.

Tracking a seal at sea
Elephant seals’ main foraging habitat is at 1,000 feet and deeper, dark and cold. In this record of 17 hours in one day of a female elephant seal’s life, she spent most of her time around 2,000 feet. She came to the surface only briefly, for two or three minutes, to breathe, get all the oxygen she needed, and dived down again. Dives deeper than a mile have been recorded.

Most of her dives were 20 to 30 minutes. She coasted most of the way, then the jagged line indicated that she was chasing and catching prey. She came back to the surface and breathed rapidly. Her heartbeat was about 100 beats a minute at the surface, as her body flushed spent carbon dioxide and replaced it with oxygen, in her blood and muscles. Because she needs oxygen to sustain her during those long dives, her muscles have oxygen-carrying myoglobin to keep her supplied.

That accomplished, she dived back down, her heart rate slowing to about 25 beats a minute. Her blood circulation became reduced, giving priority to the brain and heart, but letting the muscles and organs rely on myoglobin.

Then there’s that one long dive, over an hour past 4,000 feet. She could have been escaping from a predator, or she could have been sleeping on the way down.

Filling in the blanks
She doesn’t need to propel herself actively downward. Seals can just coast down through the water, like a falling leaf. Seals have to sleep some time. Since they are continually diving and returning to the surface, perhaps they nap on the way down on some dives.

Exactly how she hunts isn’t yet known. Those big eyes indicate that she’s hunting by sight to some extent. When I first learned about elephant seals, that seemed odd. It’s far too dark to see anything at those depths. Light from the surface penetrates only about 650 feet. But some of her prey is bioluminescent. Those squid flash light. Her sensitive whiskers can detect slight movements and help her find prey, too.

While they are migrating, elephant seals are seldom seen by humans. They’re under water, far from human observation. Digital technology allows us to gather data and use it as a route to understanding these complicated animals, which we observe only when they are on the beach, not in the deep-water habitat where they spend most of their lives.

Read more here:

Monday, June 15, 2015

June Gloom

That's what we call the fog that is typical for the Central Coast in June. Fuine my me. I'm no more a fan of the hot sun than the seals are.

They rest peacefully on the beach at this time of year.
The females are leaving, so fewer are on the beach, but subadult males are arriving. They will molt for the next month or so, then the adult males will arrive.

Fewer at the top!

The nose on this seal indicates that he is about five years old.

His nose is starting to grow, but he is not fully matire. Still, he's a good sized seal!