Monday, August 31, 2015
Birdwatching
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
From my column in The Cambria:
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:
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.
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:
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.
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.
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.
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 |
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.
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