Tuesday, January 31, 2006

Resurgence of the third major breeding site on SEFI

In recent years, the two major breeding sites on SEFI have been Mirounga Beach and Sandflat. Mirounga Beach is a small cobblestone beach with space for about 30 cows, and is also the seal's main point of access to the island. Sandflat is uphill from Mirounga Beach, situated on a rocky plateau about 3 meters above sea level. When the Farallon elephant seal colony reached its peak in numbers of breeding animals during the early 1980s, it was not uncommon to have cows also breed on the Marine Terrace above Mirounga Beach and Sandflat, an area covered in soil and plants. However, when the Farallon colony diminished in later years, cows only bred at Mirounga Beach and Sandflat (apart from some stray animals that tried raising their pups on tide-washed pocket beaches in gulches).

Now, for the last two breeding seasons cows have resumed breeding on the Marine Terrace in numbers (picture above), choosing this roomy, plant covered area that requires a longer trip overland from the sea. This year the Marine Terrace breeding site has almost doubled the number of breeding animals over last year as ever more cows are attracted to this site.

Click on the picture below to watch a full length video of an e-seal birth on the Marine Terrace.

And this change has well paid off for those animals. The pup mortality rate is 0 % so far (compared to 56% at Mirounga Beach, and 23% at Sandflat), and the Marine Terrace has produced some of the fattest and healthiest pups on SEFI. Every cow has enough space to raise her pup in peace, so the often-observed inter-female territorial fights of Sandflat rarely occur. No pup was bitten by another cow because it trespassed on its neighbor (a bite to the head is the most frequent cause of pup mortality), and the Marine Terrace alpha male, Don, has kept disturbances by subadult males to a minimum so the mothers have ample time to concentrate on feeding their pups.

So, every pup on the Marine Terrace has gained an enormous amount of weight in a surprisingly short amount of time. Here is a picture of our biggest pup on the terrace, 28 days old today, which means he is about to get weaned, and he's now bigger around than his mother.

It seems like such a good situation, zero mortality, fat pups, you may wonder why haven't cows moved up to the Terrace earlier? It may be that there was a shortage of bulls. Cows depend on the beachmaster to keep inferior quality males from harassing and mating with them, so if no large, quality bulls are available to rule the Terrace, cows will likely stay under the aegis of an established beachmaster. As populations wax and wane, the demography and age-structure of the populations change, and this can affect the population as a kind of feedback. PRBO Conservation Science is a leader in wildlife population biology, making use of our long-term data to understand the factors that cause an animal population to increase or decrease. This is crucial information for managers and policy-makers, because conservation dollars are scarce, so our efforts must be directed towards the most influential segment of the population at risk.

Monday, January 23, 2006

Meet the Weaners

Weaner is the term we use for a weaned pup. When a pup is born it is small and wrinkly, weighing about 80 pounds. Like human infants, elephant seal pups spend most of their time eating, sleeping, and crying. Pups nurse for about 28 days before being weaned. During this time the mothers eat nothing; they metabolize blubber to survive and to produce rich milk for their pups. As a pup grows fatter and fatter, its mother becomes ever skinnier. Finally the cow mates with the alpha bull and returns to the sea to find food, leaving her pup behind to fend for itself. A chubby, healthy weaner weighs about 200 to 250 pounds at this point. Currently we have five weaners on our beach.

First, there is Weaner 01 (she won't receive a real name until she returns as a cow ready to have her own pups). Weaner 01 was born on December 8th, 7 days earlier than any pup previously born on the Farallones, and 8 days earlier than the second pup born this season. As she was the first weaner, she suddenly found herself all alone after her mother left. She handled her abandonment quite well. She quickly found a nice spot on the outskirts of the colony, far enough away that she wasn't getting harassed by other mothers, but near enough that she could still watch what was going on in the colony.
Recently, all the weaners have begun to move around and explore the areas around the beach.

Weaner 01 is beginning to molt her black lanugo fur in exchange for a nice new silver one. Notice the bald patches on her head and sides where the old fur has been lost. With her old coat, she will also lose the number, which was stamped on her fur with Clairol blonde hair bleach when she was a pup so that she could be identified as the pup of Cow 01, named Giovanna. Clairol generously donates this product each year so we can harmlessly mark the seals to keep track of them all . The numbers are molted off with the fur.

Weaner 17 is the biggest and chubbiest of our weaners. His mother did a great job of fattening him up- and she did it in only 21 days! That's a full week less than average. Recently, he has been hanging around the tripod we use to weigh pups, as if challenging us to to get him on the scale. We've already determined that this year's pups are 10% heavier than last year's indicating that the cows fed very well while gestating these pups. Last year's pups were smaller because feeding conditions for cows were not so good. Cow elephant seals feed in very deep waters beyond the continental shelf, primarily on squid. The cows may be in such good condition due in part to the unusual numbers of deepwater Humboldt squid in the area last year. Here is another example of how our marine wildlife studies tell us about parts of the ocean otherwise inaccessible to us.

Weaner 20 has recently discovered a puddle along the edge of Sand Flat and seems to enjoy playing in it- at least until somone bigger comes along. Weaners often get pushed around by bigger seals, which is just about everybody else on the beach. When Weaner 20 gets chased out of the puddle, you can hear him letting the whole beach know how unhappy he is. Pup tantrums are not uncommon as the weaners learn to cope with the hardships of life without Mom. The weaners must learn to swim and eat before their blubber reserves are depleted, so a fat pup produced by a fat cow might have a better chance of surviving these early months. Your donations to the Farallones Science Program of PRBO will help us better understand these amazing animals, and the oceans we all depend on for survival. The ocean dominates this planet, and is the primary engine of global climate, so knowledge of the ocean is crucial in these days of accellerating global climate change.

Weaner 21 is the smallest of our weaners. Here you can see him with Weaner 17 behind him. Click on the photo to watch them playing. Weaner 21 was abandoned by his mother, Schnitzel when he was two days old. He was lucky though and quickly adopted himself a new mom, First Cow, and brother, Pup/Weaner 20. Cows whose pups have died or been stolen may adopt a new pup later on, but most cows do not adopt a new pup when they already have one to raise. First Cow, however, allowed Pup 21 to hang out with her pup and after a few days even began to nurse him. She has done a great job of raising both pups, further evidence of the great condition these cows are in this year!

Weaner 28, the daughter of Drip and granddaughter of Faucet -if she comes back as a cow, we are considering naming her Splash- is the youngest of our weaners. She is also the second largest- almost as fat as Weaner 17. She spent her first few days of weanerhood all by herself, far from the other weaners. It looked almost like it was too much trouble for her to drag her big body around on her small flippers, but recently she too has begun to explore and meet the other weaners.

These early weaners were lucky. They were born before the beach became crowded and had plenty of space and time to sleep and nurse in peace. Now Sand Flat, our main pupping beach, is much more crowded and chaotic. The photo below shows Sand Flat on January 22nd. The pups there now are frequently interrupted by their mothers squabbling with other cows and are often squished between other seals in the cramped conditions. These interruptions mean less time suckling each day, and slower development, but mom has to defend her pup or it could be killed by another seal. We have many pups now on Sand Flat and five other colonies around the island so there are many more weaners to come!

Thursday, January 19, 2006

The Farallon Factor strikes again!

Sea and weather conditions out here are always unpredictable and can change rapidly. Supply boats often have to be rescheduled because of storms, high seas or simply the wrong wind direction to do a safe landing. This unpredictable Farallon Factor always has to be taken into account when planning anything in a place that is still ruled by nature's forces. So, when this morning's boat was cancelled because the conditions for a North landing were too rough and the SAFE boat outboard motor was still non-functional, this was nothing out of the ordinary. The Farallon Factor had stranded the film crew and Refuge manager Joelle Buffa on the island for a day longer than planned. As you can see from the pictures below, the Ocean Futures Society crew was not idle, but used the extra day to get more gorgeous footage of the island's wildlife. Even the interns had their 10 seconds of fame. Keep your eyes open for the Farallon segment in the show "America's Underwater Treasures" on KQED sometime in October.
Fabien Cousteau and the camera team, down at the elephant seal beach.

Some extra footage in the kitchen of PRBO house, setting for Farallon Iron Chef .

We hope that Fabien, Chuck and Rick enjoyed their prolonged stay on The Farallones!

Tuesday, January 17, 2006

Cousteau arrives..... via North Landing

Today was an extraordinary day, first, because Fabien Cousteau of the Ocean Futures Society and his film crew came on the island to film part of a special on National Marine Sancuaries, and second because they did not arrive as is usual via East Landing.
As we told you in an earlier entry, Farallon equipment only functions properly in the marine environment for so long before the Farallon Factor renders it unusable. So it came as no great surprise when our previously trustworthy Honda 50 outboard motor on the SAFE boat quit working yesterday. We were unable to fix it on such short notice, so without a functioning SAFE boat we could not use the East Landing.

Because of the importance of always having functioning landing facilities, the island has not just East Landing, but a second landing on the North side of SEFI.
When Superfish tied up on the North Landing buoy this morning with captain Mick Menigoz at the helm, we were poised and waiting with the zodiac to take Cousteau and his crew aboard. Mick is a valuable member of the Farallon Patrol, the volunteer group of skippers who donate their time and vessels to keep the Farallon Science Program fed and resupplied year-around. We always need more help in resupplying the island, so if you are interested in joining the Farallon Patrol, please contact us.

Here are Sandy and Michelle securing the boat while the equipment is unloaded. Landings are always difficult procedures on the Farallones, and due to the rough seas that predominate many landings are cancelled or postponed. Today's landing went well, but the weather is deteriorating for North Landing, and it looks like the film crew might be staying a few days longer than expected.
After the landing was successfully completed all we had to do is hook on the zodiac to the new jib crane and pull it up to the landing platform 15 feet above (this time using human instead of diesel power). The boat then gets stowed away in the boathouse until the next time when weather or the Farallon Factor make North Landing the more suitable landing site.
In the meantime, Cousteau and his film crew are filming our precious and fragile biological resources. Public access to the Farallones is severely restricted, so the Ocean Futures Society film crew are bringing the island to the public through their HDTV programs. Los Farallones blog is also bringing the island to the public, so you all can see and appreciate the magnificence of the Farallon National Wildlife Refuge, and understand the hard work and perseverance necessary from PRBO Conservation Science biologists when we study the island's seabirds and seals in order to understand the ocean's workings. If you like what you see, please support PRBO Conservation Science's Farallon Program.

Sunday, January 15, 2006

The Murres Are Back

The Murres (Uria aalge) have returned to the Farallones. This penguin-like seabird is the most numerous of the twelve species that breed here on the largest seabird colony in the contiguous US. This species was decimated by an egg company that stole the eggs each year during the gold-rush era for sale to California's growing human population. With the end of egg collection, and the protection of the Farallones as a National Wildlife Refuge by president Teddy Roosevelt, the species has recovered somewhat, but is still below pre-egging numbers. Every summer, these beautiful birds raise a single chick on crowded colonies like this one on Shubrick Point. When the chicks are old enough to swim, their fathers take them to sea to teach them how to fish for themselves. The mothers disperse to fatten up in preparation for the next year's breeding effort.
After a few months apart, the adults reconvene on the Farallones on certain days when the winds and weather are just right. Murres form lifelong monogamous breeding pairs and breed each year at the same nest site, so these winter reunions are when they come together after months apart at sea and reacquaint themselves with each other and their nest sites. They also raft up into huge feeding flocks all around the island where they feed by flying underwater after their prey of juvenile rockfish, sardines, and anchovies.

The extremely productive waters of the Gulf of the Farallones provides a bounty that supports a richness, diversity and abundance of marine animals on the Farallon Islands that is unrivalled in the contiguous United States. It is hard to comprehend the riot of life that exists just outside the Golden Gate, in the midst of one of the busiest shipping areas in the country. The wildlife of California's Galapagos is under constant threat from human industry, and Murres are especially hard hit by the oil spills that too often punctuate our datasets. Help protect California's Galapagos, support PRBO Conservation Science today.

Wednesday, January 11, 2006

Elephant Seal Males Battle for Dominance

Today there was a long, exciting battle between Lloyd and Rusty. Elephant seal breeding colonies are organized into harems of cows, each defended by an alpha male. The males battle for dominance, and the right to claim a harem is hard won, with victory generally going to the larger or fiercer opponent. Lloyd and Rusty are subadult males, not quite ready for the heavyweight title and a harem of their own, but these battles establish ranks and train the seals for the big event when they actually fight for the prize. Here is a video from last year of the bull JD chasing Altamont off the Sandflat and away from his harem of cows. This year, JD was deposed from the Sandflat harem by Nero, and Altamont has a harem on Shell Beach.

Sandflat is currently the largest harem on the Farallones, with around 65 cows at the peak of breeding in mid-January. After the islands were re-colonized in 1971, the largest harems became established on West End at Shell Beach. However, the Shell Beach colony began a steep decline after the intense El Nino event of 1982-83 scoured the access beaches away and left an 8-foot vertical wall in the path of cows trying to breed there. This severe El Nino, along with the 1991-92 and 1997-98 were the three most intense El Nino events in the past 150 years. Over the past 40 years, PRBO scientists have documented numerous impacts on breeding, survival, and diet of marine predators from these and other ocean-climate events thanks in large part to the detailed data we collect at the Farallones. Conservation requires science, and PRBO provides some of the best science in the world.

Tuesday, January 03, 2006

After the storm there was the flood

The big storm that caused so much destruction on the mainland did not leave the Farallones untouched. Because of the heavy rain, the meager soil layer on the island was finally so saturated with water that a lake suddenly formed around the PRBO house. The elevated cartpath had blocked all the runoff, and this was the sight that greeted us when we opened our front door in the morning to go out to the beach.

It wasn't just our house that was threatened with the fate of Atlantis; water all over the island was looking for the shortest route to the sea. Another obstacle in its path, the Pipe Shop near East Landing. The back wall of the shop has sprouted a fountain and the water now runs freely in the Pipe Shop through the back wall and out the front door in a steady stream.

Meanwhile back at the house the water was still rising, the flood alarms for our wastewater system were set off and were screaming over the island. The water also found it's way in the crawlspace under the house. The situation started to get desperate, something had to be done!

So Derek blew up the levee to save the town! Raised in the delta, he was familiar with this crude but effective tactic, the Lodi solution worked like a charm.

With the old drain pipe re-excavated the way for future floodwaters is now free again. The 120-year-old Lightkeepers House survived once more by the ingenuity of the island personel.

PRBO's partnership with the US Fish and Wildlife Service is to monitor the biological resources, and to maintain a presence on the island to care for all its structures and systems. Most of the year, PRBO biologists are the only people on the island and are responsible for keeping the electricity, drinking water, and wastewater all flowing properly. Every structure is over 50 years old, some much older, and all require constant maintenance. Machinery does not enjoy the marine environment, and as such, equipment is constantly breaking down. We are completely off the grid, self-sufficient for our power, water, sewage, and communications. There are no plumbers or electricians to make a house call, we have to fix everything ourselves. Or if we can't fix it, patch it up until the next boat can bring a replacement part, or Jesse, the Refuge's Mr. Fix-it, sometimes three or more weeks down the road. Life on the Farallones is every day a magnificient wild nature spectacle, but the Farallon Factor looms large over our island systems, and it's never too long before we're up to our elbows in grease or up to our ankles in wastewater.

Monday, January 02, 2006

New Year's Storm Pummels The Farallones

Huge swells pounded the island and rain dumped out of the sky, flooding the pipe shop and forming a lake around the house. The new year roared in with a major tempest that blasted the landing with monster waves, and whipped the island with winds so fierce they threatened to blow away everything not bolted down. These extreme conditions are seen nearly every winter on the Farallones, making our field work difficult but also providing us with our water supply. We harvest rainwater each winter to supply all our water needs throughout the year. California's climate is a wet winter and dry summer, so whatever rainwater we can collect from December to March has to last eight months until it rains again. Our rainwater collection system was built for the lighthouse keepers and navy station that used to be out here, and is around 100 years old, but still functions great. When the giant swells slam into the island and I feel the rock tremble under my feet, I can believe the stories those old-timers told that the island is hollow, filled with an enormous 'Lost World' cavern.