It’s big, it’s gray and it’s here to stay!

Back in December, we told you about the demise of the crane at East Landing (see It’s big, it’s blue, it’s broken!). This is our main way of getting people and gear on and off the island. The ocean around the Farallones can be very rough, especially during winter storms or high swells and there is no safe place to land a boat. So we use the crane to lift all people and gear up onto the island. Well, after 21 years of faithful service (and constant battering from a truculent ocean) the crane had suffered a great deal of corrosion and needed to be replaced. 

The old crane taking a beating during an early winter storm

Transporting the new crane to SEFI

Replacing a 20 ton piece of equipment on a remote island is no easy task. Biologists are a generally handy group of folks, but in this case, we needed to call in the experts. So the USFWS called up Sheedy Drayage, the company that installed the crane in 1989 and worked out the complicated logistics of removing the old crane, getting it repaired and then getting it back to the island. This required the assistance of the Air National Guard and Aris Helicopters to lift the heavy crane parts and transport them to the mainland for repairs.Then of course they also had to get them back to the island after the repairs had been completed.

Aris Helicopter preparing to hoist crane parts into place

Of course, getting the new crane back to the island was only the first step. The tricky part was getting it re-assembled and installed at the landing. This required good weather, perfect timing, great balance and a whole lot of rigging to temporarily secure the various parts until everything was safely bolted together in its proper place. To most of us this would seem a Herculean task, but for the intrepid crew from Sheedy and the experienced pilots from Aris, it was just another day at the office. 

Gently dropping the new stiff leg into place

Hooking up the parts as they are dropped into place

When the crane disappeared from the island in December, many of us worried that it would be many months to a year before it could be reinstalled. But, thanks to the tireless effort of USFWS personnel, efficient work by Sheedy, tremendous assistance from Aris and the Air National Guard, and lots of good luck, the new and improved crane was returned to the island in mid-March. This one looks a little different. It is galvanized to help prevent the corrosion that caused the eventual demise of the old crane, but it works just the same.

New Crane installed and ready to use

Needless to say, island residents are extremely happy to have the crane back, allowing us to safely and efficiently conduct landings, even in rough spring conditions. We would like to thank Zach Coffman, Gerry McChesney and Mendel Stewart of the US Fish and Wildlife Service, Al Pietrocelli and the crew from Sheedy, the Air National Guard, Aris Helicopters, the National Park Service and all those who contributed in one way or another to making this immense project happen.

Sheedy crew at East Landing
All photos in this post are courtesy of Zach Coffman, USFWS

A Spring Transition

Blowing so hard even the gulls can't stand up!

According to my oceanography textbook, the spring transition is when weather and ocean conditions shift from predominantly winter conditions to spring/summer conditions and marks the beginning of the upwelling season. Winter is typically dominated by southerly winds, frequent storms and rain. Whereas spring and summer are typically dominated by strong north/northwesterly winds, clear skies, and more arid conditions. The wind often blows so hard during the spring that it is difficult to walk around. (see A Mighty Wind posting from April 2009).

This shift is extremely important for biological productivity in the waters around the Farallones. The strong northwesterlies drive the process of upwelling that brings cold nutrient rich water to the ocean surface and, coupled with abundant sunshine, spurs on the production of phytoplankton that forms the base of the food chain.

On the Farallones, however, the spring transition is more than just a change in the winds. The whole island is transformed to make ready for the next wave of wildlife (and wildlife biologists) to inhabit these rocky shores. The elephant seals have finished their breeding season, the last pups have been weaned and the adults have departed the island in search of food to recover the fat reserves they depleted during the long winter fast. Along with them went the winter crew. After spending the last 3 ½ months diligently caring for the island and its wildlife, they have returned to mainland to write up their findings, pursue other interests and prepare for next year. The abundant rains during this past winter have produced a lush blanket of vegetation covering the entire island. The Farallon weed (Lasthenia maritima) is in full bloom and taller than we have seen in many years. 

The marine terrace and hill in spring bloom

But most importantly to those of us now on the island, the spring is when the seabirds return to the island to set up nesting and begin breeding. Over the next six months, the seabird crew will dedicate our energy to studying the population trends, survival, diet, and reproductive success of the 13 species of seabirds which call these rocky islands home. More than a quarter million seabirds breed on the Farallones each year, including approximately half the world’s population of Ashy Storm-petrels, the world’s largest breeding colony of Western Gulls, and the largest colony of Common Murres in California with approximately 250,000 birds!

Common Murre breeding colony on Shubrick Point

Cassin's Auklet with nest box

So far, things are looking good. Cassin’s auklets have already begun breeding in good numbers and the other breeding species have returned to meet up with their mates, re-establish their territories and begin the process of nest building. Although we are in the midst of an El Niño, the effects seem to be minimal on the Farallones so far. We may even have a new breeding species on the island this year. A pair of Common Ravens has been present on the island for the last few months and has recently been observed gathering nest material. Raven’s haven’t bred on the Farallones since 1911! It will be interesting to see what effect these intelligent predators have on the seabird colonies.

Common Raven carrying nesting material

An Intertidal Journey

This past week, PRBO biologists hosted special visitors to the island - a team of scientific experts on plants and animals that inhabit the intertidal zone. The Gulf of the Farallones National Marine Sanctuary, a program of NOAA, has been conducting surveys of the South Farallon Islands' intertidal zone every year since 1992. This long-term monitoring provides valuable baseline information on species composition and richness in a relatively pristine area.

Documenting species composition in permanent plots.

The intertidal crew includes biologists from the Sanctuary, the California Academy of Sciences, and Tenera. They inventory invertebrates, take photographs for archives, and document algae cover in permanent plots at 6 sites on SEFI and West End. Surveys are conducted 3 times per year, weather permitting of course.

Working conditions in the intertidal zone can be rough, especially during winter storms.

This year, 5 new species were documented. Moreover, a black abalone (Haliotis cracherodii) was sighted here for the first time since 2000. Black abalone, once the most abundant species of abalone in California, is now perilously close to extinction due to past overfishing. It is currently federally protected under the Endangered Species Act. The South Farallon Islands are at the northern extent of its range.

Black abalone, an endangered species, was documented here for the first time in 10 years.

The intertidal crew included Dr. Rebecca Johnson, an expert on opisthobranchs from the California Academy of Sciences (you can link to the Academy's Rocky Shore Partnership blog here). These marine molluscs, also known as nudibranchs or sea slugs, have reduced, internalized, or completely lost their shells over evolutionary time. Their brilliantly luminous neon colors in distinctive patterns serve as a warning to potential predators - many are foul tasting. But their warning colors also make them some of the most beautiful animals inhabiting the oceans.

Horned Aeolid (Hermissenda crassicornis), one of the more common nudibranchs on the Farallones.

Clown Dorid (Triopha catalinae)

The intertidal zone is one of the harshest environments on Earth. The zone is exposed to the air at low tide and underwater at high tide, and is continuously pounded by the surf, which on the Farallones can be very rough indeed. The plants and animals are well-adapted to their extreme environment. The relative lack of pollution and absence of human trampling on the Farallones allow biologists a glimpse into the structure of an intertidal zone comparatively free of direct human impacts. This crucial information is yet one more reason why the Farallones are such a tremendous resource to our understanding of the ocean ecosystem.

Plants and animals compete for space in Jewel Cave, one of the loveliest tidepools on SEFI.

Strawberry anemones in Jewel Cave.

Chitins, urchins, anemones, and sea stars dwell amongst sponges and algaes.

Farallones in Bloom

The wildflowers are in full bloom on the Farallones and due to abundant rainfall this year they are particularly prolific. While the native maritime goldfields (Lasthenia maritime) and marsh and sticky sand spurry (Spergularia spp) continuously sported a few flowers throughout this wet winter, in the past couple of weeks the island has truly burst into color. The goldfields are knee-high in some areas of the marine terrace.

Maritime goldfields (Lasthenia maritime) is the dominant plant on the Farallones.

The cart path overgrown with maritime goldfields.

Sticky sand spurry (Spergularia macrotheca)

One of the rarest and arguably most beautiful native flowers on the South Farallon Islands is the seaside daisy (Erigeron glaucus). This lovely low-growing spreading plant has curled, velvety leaves, bright yellow centers, and lavender petals and grows mostly on rocks on the north side of Little Lighthouse Hill and on the path to the murre blind on Shubrick Point. We found this specimen blooming on the rocks above the new copper Sea Lion Cove blind.

Seaside Daisy (Erigeron glaucus)

It's a Superweaner!

Most female elephant seals nurse their own pups exclusively until weaning, and are fiercely protective of their pups - with good reason, as the main cause of pup mortality on Sand Flat is being bitten in the head by other cows. However, some cows that lose their pups will adopt orphans and raise them as they would their own. Occasionally, some lucky pups are suckled by two mothers or are adopted by a pupless female after being weaned by their own mother. They are known in the elephant seal world as "double mother suckers", or "superweaners." These weanlings can grow to be twice the mass of normal weanlings!

Below is a movie of a superweaner on Sand Flat. The cow, named Robin Robertson, either stole this pup after losing her own, or she may have accidentally switched pups with another cow and ended up with a pup older than her own. He is so old that he has already molted most of his black pup fur, yet he continues to nurse. We have two additional superweaners, both adopted by cows from Mirounga Beach who lost their pups in the mid-January storm.

The Farallon Arboreal Salamander

The only native terrestrial vertebrate inhabiting the South Farallon Islands year-round is the arboreal salamander, Aneides lugubris. The Farallones population is considered a sub-species, A. lugubris farallonensis, but is closely related to arboreal salamanders at Point Reyes peninsula. The Farallones were connected to Point Reyes 10,000 years ago when sea levels were much lower.

Aneides lugubris farallonensis.

On the mainland, this species is associated with oak woodlands. It is described as arboreal because of its unique ability and propensity among salamanders to climb trees: the enlarged toe tips and prehensile tail is adapted for climbing, and individuals on the mainland have been found in tree cavities as high as 60 feet above the ground!

However, trees are in rather short supply here on the Farallones - so what gives? Although its common name suggests that this salamander lives in trees, it is actually found mostly under rocks and logs and in crevices and burrows, and its arboreal tendencies may be somewhat overrated. Seabird burrows cover almost the entire Southeast Farallon Island and, together with the many rocks, provide abundant cover for salamanders.

The arboreal salamander has a prehensile tail to facilitate climbing.

One herpetologist noted that "this curious genus [Aneides] is furnished with by far the most powerful dentition of any existing salamander..." Given that the arboreal salamander is the biggest species of its genus, these guys have especially large and powerful teeth, and have even been known to bite the unsuspecting PRBO biologist!

Arboreal salamanders are lungless salamanders (family Plethodontidae) that breathe through their skin. This renders them sensitive to changes in water or air quality, making them good indicators of ecosystem health. PRBO biologists initiated a long-term monitoring study of the Farallon arboreal salamander in 2006.

In the dry season from May to October arboreal salamanders retreat to burrows deep beneath the ground where they guard their eggs and hatchlings and wait for the rains to return. They are only active near the surface during the winter rainy season. When at the surface they are strictly nocturnal, emerging at night to forage for beetles, isopods, and other insects. During the day they remain in stone walls and crevices and under rocks and boards.

Coverboards are placed in pairs along the path from the PRBO house to North Landing.

We placed more than 100 permanent cover boards along the path from the PRBO house to North Landing. We check under the boards for salamanders every 2 weeks from November to May, the period of greatest surface activity. When we capture a salamander, we measure and weigh it, check for eggs (you can see eggs through their skin), and take photos of its spot patterns. Each salamander's spot pattern is unique, so we can individually identify them using our photo database.

A biologist measures a Farallon arboreal salamander.

Each salamander has a unique spot pattern, allowing biologists to individually identify them.

Unfortunately, a larger proportion of amphibian species are at risk of extinction than any other group of animals. Salamander populations throughout the world are threatened by chemicals, infectious diseases, and habitat loss. By studying the Farallon arboreal salamanders, we can understand their population dynamics and hopefully ensure a future for this special and unique creature.

A Superlative Creature

Noted elephant seal biologist Burney Le Boeuf once stated, "if you like superlatives, you will love this animal."
Consider this list from Le Boeuf and Laws' seminal 1994 book on elephant seals:

Elephant seals are the largest of the 34 extant species of pinnipeds in the world, and one of the most sexually dimorphic marine mammals - adult males are several times more massive than females.

Alpha bull elephant seal mates with a cow.

Elephant seals are extremely polygynous compared to any other large vertebrate.  One male might mate with up to 200 females, while most males will never mate.

Females fast the entire time while nursing their pups, and the largest breeding males fast for more than one hundred days during the breeding season.  After losing up to 40 percent of their body mass while fasting, females then migrate at least 5,500 km and males at least 11,000 km into the ocean to find food.

A cow aggressively defends her pup while nursing, but her weaned pup must learn to swim and hunt on its own.

Elephant seals dive deeper and longer than any other pinniped, and they spend more time submerged during their long aquatic wanderings than most whales!

Elephant seals even sleep underwater.

No other large vertebrate has come so close to extinction and made such a rapid recovery as the northern elephant seal.  And thank goodness it recovered:  the South Farallon Islands and indeed the world would be a much poorer place without this most superlative of creatures.

 PRBO biologists tag all weaned pups on SEFI and West End for permanent identification.

Molly is Back!

Molly, the brant who hangs out with the western gulls on SEFI from time to time, is back after a several-month absence. Welcome back, Molly!

Peak of the Elephant Seal Breeding Season

The last days of January are the peak of the northern elephant seal breeding season on the South Farallon Islands. Most cows have already arrived and given birth on the rookeries, which echo with the sounds of cows calling to their screaming pups and males bellowing to intruders. We can hear the cacophony all the way up at the PRBO house! SEFI's Sand Flat (pictured on the left), where Rusty is the reigning alpha bull, currently has 73 cows, 52 live pups (9 dead), and 2 weaned pups, including the cow Daniela's weanling. The Marine Terrace colony has 15 cows, 11 live pups (1 dead), and 2 weaned pups, including the cow Shaye's weanling, with Flaccido Domingo the alpha defending this harem. Mirounga Beach, where McHammer is alpha male, has only 4 cows and 2 pups, after last week's massive storms washed out 3 pups and forced 16 cows up to Sand Flat, including the cow Aprile and her pup who are doing fine! On West End, 8 cows and 5 live pups are at Pastel Cave Highlands, defended by Felipe, and 10 cows, 4 live pups (3 dead), and 1 weaned pup are on Shell Beach with Bedlam Boy as alpha bull.

Flaccido Domingo claims the cow Carmen, in a display to a male challenger.

Northern elephant seals are fascinating in their ability to live off their blubber for long periods of time, a critical part of their life-history strategy. Called 'capital breeders' because they feed their pups entirely from their stored blubber reserves, adult females fast the entire time they are nursing their pups, about 30-35 days. 'Income breeders' like California sea lions must leave their pup on the beach occasionally to forage for more energy to maintain themselves and their growing pups. By not having to forage while nursing, the elephant seal cow transfers a great deal of milk energy to her pup in a short time. This allows her to wean the pup quickly and return to sea to prepare for future offspring by foraging on her own without encumbrance. The largest breeding males fast for more than 100 days, allowing them to be vigilant in fighting and defending their harem of cows from other male challengers, and then mating with every receptive female as their reward. Weaned pups live off their blubber for several months while they learn to swim and dive before first heading off to sea to forage.

Rusty bellows a warning to a male attempting to intrude on "his" cows.

Rusty's reward for defending the harem is to mate with >70 receptive females!

Given that elephant seals must live entirely off their blubber while on land, it is no surprise they spend as much time as possible sleeping. Elephant seals undergo sleep apnea (holding their breath) for up to 25 minutes, enabling them to reduce water loss from respiration and to slow lipid metabolism - the only source of water for a fasting seal.

Cows, pups, and a bull sleep long hours to save water and energy.

Cows do not eat for 35 days or more while transfering milk energy to their rapidly growing pups.

Weaned pups live off a thick layer of blubber while learning to swim and dive.

Stormy Weather

The Farallon Islands have been pummeled by a series of major storms over the past few days. The massive swells crashing into the island are awe-inspiring and the intermittent heavy rains are filling our cistern with much-needed drinking water to last PRBO biologists the rest of the year.

The huge waves - especially at high tide - wreaked havoc in our elephant seal breeding colony. Mirounga Beach and Log Channel filled completely with water. Just prior to the storms, Mirounga Beach had 16 cows and 5 pups. Once the storms hit, we thought all pups there were washed out. However, yesterday we spotted 2 tenacious pups still alive and attempting to move to higher ground! Many of the Mirounga Beach cows moved up to the protected Sand Flat, bumping up the population on the flat from 50 to 62 cows over just 2 days.

The storms are expected to last a few more days, with a break over the weekend and then more rain next week! Luckily the new blind on the hill overlooking Sand Flat not only hides us from the skittish California sea lions, but also provides us some shelter from the elements while we continue to monitor the elephant seals every day, rain or shine.

20 Orca seen today!

During this morning's lighthouse watch, I saw 20 Orca swimming west of the island, headed southeast.
5 big males were in the group and perhaps 4 juveniles.
Very exciting!

The Battles Begin

The genus Mirounga comprises the northern and southern elephant seals, the largest pinnipeds in the world. Our large northern elephant seal bulls on Southeast Farallon Island weigh up to 5,000 pounds – some particularly massive ones are even heavier. Northern elephant seals are highly sexually dimorphic, with males weighing 3 to 6 times more than the females. While smaller than their southern counterparts, northern elephant seal bulls have a longer nose and more pronounced chest shield of scarred and thickened skin. This chest shield is associated with fighting, and the nose is thought to act as a resonating chamber that amplifies their bellow to warn off other males.

Pink chest shield and large nose on Bubba.

Winter marks the season of bull battles as males compete to dominate the harems of females who have come ashore to give birth, nurse their pups, and breed. Rusty, our alpha bull last year, has returned and is holding the Sand Flat harem again, with 15 cows as of January 3, including Daniela, Kyra, Eone, and Lodi, and 7 pups. Kyra and Eone were both born on SEFI in 1999.

Kyra with her newborn pup on Sand Flat.

Flaccido Domingo is the beta bull on Sand Flat. Time will tell whether he challenges Rusty for the top spot.

Flaccido Domingo is second on Sand Flat, but wary of mighty Rusty.

Speaking of challenging for the top spot, the bull Bubba attempted to do so on December 31, leading to his demise. Rusty killed Bubba in a brutal, hour-long battle in which Bubba got stuck between two rocks in Log Channel Beach. This happened to Nero in 2007, when he was killed by Don Fransisco after getting wedged between the same two rocks.

Rusty and Bubba battle in Log Channel Beach.

Most elephant seal fights do not end in death, but occasionally when two bulls are closely matched, the winner will continue to batter the loser until he is permanently eliminated. The battle was a sobering reminder to PRBO biologists of the realities of nature and that life itself is at stake for these animals. You can view a part of the battle below, but be warned that it is not for the faint of heart.

The harem on the Marine Terrace of Sand Flat is small but growing. There are currently 3 cows and 2 pups, including new cow Shaye. McHammer, not quite a bull, is dominating this harem. He is 9 years old, born and tagged on the Farallons in 2001.

McHammer on the Marine Terrace.

Mirounga Beach has no pups yet, and cows so far have been just passing through. Felipe, nearly a bull, has been seen in Mirounga Beach. Similarly sized Mein Gott is biding his time on Lower Arch Terrace. McHammer, Felipe, and Mein Gott are known as "SA4" seals, or 4th-year subadults. The next step up is a bull.