A pair of Cooper Island Black Guillemots. Image Credit: George Divoky
A pair of Cooper Island Black Guillemots. Image Credit: George Divoky
In a breeding season and field season that has been a tough one for both the Black Guillemots on Cooper Island and the investigators studying them, today was a day of celebration as morning nest checks revealed that the oldest nestling on the island had departed for the sea during the night.
The first fledge of the year is always exciting since it is an important benchmark in our field season, which begins with recording the owners of nest sites and continues with observing the dates of egg laying and monitoring the hatching and subsequent growth of nestlings. While it is the parent birds who get all of the credit for a successful nesting season, we cannot help but feel some satisfaction having monitored daily the details of their three-month reproductive cycle. Additionally, and certainly now with the recent decline in the size of the colony, a fledged chick provides hope for the future. With sufficient luck, in three years the chick that fledged last night will return to Cooper to join the breeding population.
So we congratulate the proud parents White-Black-Gray, a bird fledged from Cooper Island in 1995 who has bred here since 2000, and Blue-Blue-Yellow, an immigrant (likely from one of the large Russian colonies) who had been breeding on the island for the past twelve years.
We are hoping that in the next few days their now independent fledgling will be joined by its sibling and a good number of the 50 birds that remain in nest sites.
This field report is part of an ongoing series titled Arctic Change centered around George Divoky’s 44th field season studying Black Guillemots, sea ice, and climate change on a remote Arctic island off the coast of Alaska. To donate and support Divoky’s work on Cooper Island, visit the Friends of Cooper Island website.
A parent brings Arctic cod to their hungry chick waiting at the nest. Image Credit: George Divoky
Hatching is finally over with one very late egg hatching today after having been incubated for 34 days; 28 days is normal. The oldest nestling is 16 days old; the chick is gaining weight and doing well like all of the other 45 nestlings.
While the main pack ice is well offshore, the Marginal Ice Zone, where ice covers from 18 to 80 percent of the ocean’s surface, extends south to the entire Alaskan Beaufort Sea coast, including Cooper Island. The seascape visible from the north beach now has widely scattered floes, some with rather high vertical relief breaking the horizon, in a nearly flat calm sea. This differs greatly from what was present last year when the first week in August had no ice visible with large swells breaking on north beach. More importantly, last year at this time the sea surface temperature was well above 4 degrees Celsius while this year it is less than 2 degrees Celsius. The guillemot’s preferred prey, Arctic Cod, are typically found in waters from -2 to 4 degrees.
A Multisensor Analyzed Sea Ice Extent (MAISE) image shows why George is seeing ice off of Cooper Island. Image Credit: National Snow and Ice Data Center (NSIDC)
The ice and water temperature conditions are ideal for the parent birds provisioning. Arctic Cod has comprised well over 90 percent of the prey being fed to chicks this year. The two oldest chicks, hatched on July 21, weighed 35 grams at hatching and now weigh 275 grams and 245 grams – the larger of the two experiencing an almost seven-fold weight increase in a 15-day period. A growth rate that rapid requires readily available prey that is both abundant and high energy, as well as two dedicated parents to return to the nest site with a fish every hour. Similar high growth rates are occurring at other nests.
This condition of the nestlings could not be more of a contrast with early August last year. Then, there was widespread mortality of younger siblings as parents could only find enough prey to maintain a single nestling. Arctic cod were absent for much of the nestling period with sculpin and juvenile sand lance comprising most of the prey. Guillemot parents turn to these alternative prey only when Arctic Cod are not available. Sculpin, with their large bony and spiny heads, are hard for nestlings to hold and swallow. They are frequently rejected with numbers building up in nest sites as the young wait for a more preferable fish.
Blob sculpin, bony fish guillemot chicks struggle to consume, lay uneaten in a nest case. Image credit: George Divoky
For the moment our daily nest weighing and measuring of guillemot nestlings has been a very positive experience. However, based on what we have seen in the last decade, we know that conditions can change rapidly in August. A strong south wind could move the ice well out of the guillemots’ foraging range or warmer waters could move eastward from the Chukchi and drive away Arctic Cod. We also know that larger and older nestlings are more able to survive changes in prey availability and that the current high growth rates will allow more individuals to survive to fledging.
This post was updated on August 11.
This field report is part of an ongoing series titled Arctic Change centered around George Divoky’s 44th field season studying Black Guillemots, sea ice, and climate change on a remote Arctic island off the coast of Alaska. To donate and support Divoky’s work on Cooper Island, visit the Friends of Cooper Island website.
Cooper Island Black Guillemot in May 2017. Image Credit: George Divoky
Cooper Island Black Guillemot in May 2017. Image Credit: George Divoky
Nature, when observed or monitored for any extended period, typically provides a predictability that is reassuring in its consistency and sufficient surprises to keep one engaged.
For over four decades, my first task after I set up camp was a census of the Cooper Island Black Guillemot colony. This year was an excellent example of this balance of the expected and unexpected.
Colorful bands make it easy to identify familiar birds and newcomers (without bands). Image Credit: George Divoky
Since the 1970s, the majority of the birds breeding in the colony have had, in addition to a numbered metal band, a unique combination of color bands allowing identification with binoculars of individual birds. My census of the colony consists of recording the number of occupied nest sites and the color band combinations of the individuals occupying each site. This allows me to determine the birds who survived the winter since last year’s breeding season and whether they have retained the same nest site and mate.
Black Guillemots, like most seabirds, have high annual survival of adult birds and high mate and nest-site fidelity. On average 90 percent of the individuals breeding on Cooper have returned the following year with mate and nest-site fidelity over 95 percent. With loss of breeding birds so uncommon and changes in mate and nest site so rare, past censuses consisted primarily of confirming last year’s pair was again occupying a particular nest site. For the small number of nests where one member of a pair did not return, there typically was a new recruit already occupying the vacancy by the time of my census–either a bird banded as a nestling on Cooper Island or an immigrant, indicated by its lack of any bands.
In the past, the high survivorship of breeding birds meant that some of the individuals I resighted each June were ones I had seen for over 20 years, and in many cases had known since I had weighed them daily as a nestling. The resightings of these individuals as adults provided an annual touchstone that was an important part of both my emotional and scientific connection to the colony.
My initial census of the colony this year was unlike any in the past. The loss of breeding birds over the winter was the highest on record. Nearly one-third of the 170 birds that bred in 2017 not returning to the colony in 2018.
As mentioned in an earlier post, many of the 50 pairs that had eggs this year (down from 85 in 2017 and 100 in 2016) consisted of widowed birds that both lost a mate over the winter. The decrease in breeding population was exacerbated by the paucity of previously nonbreeding birds present to recruit into the breeding population. Some established breeders widowed over the winter are the sole occupants of their nest sites. Even pairs that did survive the winter have shown much lower mate and site fidelity than I have observed in previous years.
The disturbingly high percentage of birds lost to overwinter mortality comes as a major surprise but a simple percentage fails to capture the full impact of what I experienced during this year’s census.
George’s “Cover Girl,” featured here on a December cover of Audubon Magazine, didn’t return to Cooper Island this year. Image Credit: Peter Mather for Audubon
Many of the individual birds I have known for decades were among those absent from the colony. Most notable was Yellow-Gray- Green, a 21-year-old female banded as a chick in 1996 and breeding on Cooper since 2001. She was featured on the cover of last winter’s Audubon magazine. Another individual absent this year with an even longer history on the island is White-Gray-Blue, who fledged from Cooper in 1989 and bred on the island during 23 years of rapid environmental change including of decreases in sea ice, warming ocean temperatures, increased polar bear nest predation and major shifts in prey availability.
While examining this year’s colony census at the level of the individual bird, versus a review of declining numbers is disheartening, it also provides some reasons for optimism–a rare feeling this field season.
My census found that a number of birds fledged from Cooper in recent years recruited into the breeding population this year, starting what I hope will be a long and productive career as breeders. These birds, and their young–the fledging chicks we hope they produce later this summer–provides one both with optimism and motivation to maintain the long-term study. As Hannah Waters pointed out in her excellent article in Audubon magazine, the guillemots are going to have to adapt and evolve for the colony to survive in a rapidly warming Arctic.
The hope that this year’s first-time breeders and their young will find a way to maintain the colony during the major changes occurring in the Arctic allows me to maintain a positive attitude as I continue to monitor this year’s breeding season.
This field report is part of an ongoing series titled Arctic Change centered around George Divoky’s 44th field season studying Black Guillemots, sea ice, and climate change on a remote Arctic island off the coast of Alaska. To donate and support Divoky’s work on Cooper Island, visit the Friends of Cooper Island website.
A lone Black Guillemot and sea ice off Cooper Island. Image Credit: George Divoky
A lone Black Guillemot and sea ice off Cooper Island. Image Credit: George Divoky
Black Guillemots and sea ice off Cooper Island. Image Credit: George Divoky
Mandt’s Black Guillemots. Image Credit: George DIvoky
George Divoky frets–with good reason. In 2016, CNN Correspondent John D. Sutter called him the man who is watching the world melt. The description is as distressing as it is apt.
George sends us regular dispatches from a small field camp on Cooper Island, about 25 miles east of Utqiaġvik, where he has studied a colony of nesting Mandt’s Black Guillemots for the last 44 years. Since his work began in 1975, the research has morphed into one of the longest-running studies of seabirds, sea ice, and climate change.
Guillemots look like small penguins headed off to a fancy party replete with ice sculptures and all-night dancing. Unlike other seabirds that migrate out of the region seasonally, they live out over the frigid waters year-round, only returning to land to breed and fledge their young–this makes them an excellent indicator of how climate change is impacting the Arctic.
Weather delayed the start of this research season in early June. While warm temperatures in the Arctic have made headlines in recent months, unusually late snow and ice kept the guillemots from reaching their nesting boxes until mid-June; the first egg was laid on June 24.
His communications are tinged with an effort to buoy spirits–I’m guessing his own more so than ours. This week, the bad news came first: a 29-year-old female died. He wrote that she had been banded during the first George Bush administration. (While many humans rely on a simple Gregorian calendar, George’s memories appear to be synchronized according to a timeline rooted firmly in geopolitics.)
Bad news was followed with happy; two siblings from the 2014 cohort returned and recruited partners for breeding.
Otherwise, it’s been a stormy week on the island. On July 20, he wrote that the wind was finally dying down. A bad week for the infrastructure, the camp’s weather station was blown over and part of the heavy-duty WeatherPort tarp separated from the frame, which caused a number of things to get wet. On Wednesday he saw record high rainfall for that date.
Egg laying hit an all-time low this year, with fewer breeding pairs than any previous year.
He’s asking questions about how changing ice conditions will impact these seabirds – his seabirds. In his most recent field report, he spoke at length about the relationship between the guillemots and nearshore sea ice. The location of the sea ice impacts how far parents will have to fly to access suitable prey for their chicks. Increased travel time means greater energy expended by parents – for seabirds that live predominantly out in open waters, it’s all about balancing resources and energy. The presence or absence of sea ice combined with the temperature of the ocean waters impacts the availability of Arctic Cod, the small nutritious fish the guillemots prefer.
George hopes the slowly departing nearshore sea ice will keep ideal prey in foraging range for the seabirds. He wrote, the cod is “urgently needed for the colony to reduce its current population decline.”
A MODIS image from July 11; snow and ice are cyan color while clouds tend to be more grayish. Image Credit: NASA Worldview
A MODIS image from July 16; snow and ice are cyan color while clouds tend to be more grayish. Image Credit: NASA Worldview
David Douglas is a research wildlife biologist for United States Geological Survey (USGS) Alaska Science Center; he and George are frequent collaborators. This week he emailed the MODIS images displayed above and wrote that Cooper Island was pretty well surrounded until July 16 when the persistent ice immediately around the island broke up and melted.
Studies like George’s will help scientists to better understand the ramifications of long-term warming and less sea ice for wildlife in the region. Impacts to wildlife will directly affect the lives of the people who depend on subsistence fishing and hunting for survival.
Warming Arctic conditions have persisted with 2018 reaching record lows for sea ice extent, according to a report published by NOAA and University of Alaska Fairbanks’s International Arctic Research Center.
Late ice formation and early retreat in the Chukchi and Bering Seas impacted local communities by making travel for subsistence hunting and fishing dangerous and, at times, impossible. Storm damage and erosion was worsened by exposed shorelines, left unprotected by a lack of sea ice. Island villages and coastal communities experienced flooding and property damage as well. You can read more about the storm impacts here and here.
The report attributes late and minimal ice coverage to warmer temperatures, particularly over the last four years. Increased temperatures combined with stronger storms helped break up weaker ice.
In 2018, there was less sea ice in the Bering Sea than any year since 1850, when commercial whalers began recording this data. Experts agree, loss of sea ice is a result of climate change. Continued warming creates a feedback loop where warming temperatures melt ice; without a reflective snow and ice covering, the ocean absorbs more of the sun’s warming rays and temperatures continue to rise.
Sea ice since 1850. Image Credit: NOAA and University of Alaska Fairbanks International Arctic Research Center (UAF-IARC).
As for future winters, what can people expect to see if warming continues at current rates?
“Communities need to prepare for more winters with low sea ice and stormy conditions. Although not every winter will be like this one,” concludes the report, “there will likely be similar winters in the future. Ice formation will likely remain low if warm water temperatures in the Bering Sea continue.”
And for George’s seabirds? How many birds will successfully fledge this year? How many will return next?
We’ll just have to wait and see.
This piece is part of an ongoing series titled Arctic Change centered around George Divoky’s 44th field season studying Black Guillemots, sea ice, and climate change on a remote Arctic island off the coast of Alaska. To donate and support Divoky’s work on Cooper Island, visit the Friends of Cooper Island website.
George collecting data at nesting case in 2015; the cases were added once polar bears became regular visits on the island. Image Credit: George Divoky
George collecting data at nesting case in 2015; the cases were added once polar bears became regular visits on the island. Image Credit: George Divoky
The Cooper Island Black Guillemot colony experiences a major decrease in breeding pairs as long-term decline accelerates.
As of July 6, egg laying ended at the Cooper Island colony and the number of breeding pairs is the lowest it has been in four decades. Only 50 guillemot pairs have laid eggs, down from 85 pairs last year, 100 pairs in 2016 and 200 pairs in the late 1980s.
Cooper Island breeding pairs over the years; it is important to note that the number of available sites has not decreased as the population has decreased, meaning some environmental factor has likely been decreasing the population. Image Credit: Jenny Woodman
A primary reason for the decline was increased overwinter mortality, with almost one third of the last year’s breeders failing to return to the colony. The long-term average for overwinter mortality is ten percent. Also contributing to the decline was a paucity of recruits to occupy the vacancies created by the mortality. Many of this year’s pairs are composed of two birds that lost mates over the winter. All recruitment that did occur were of birds that had fledged from Cooper Island. Immigrants used to constitute the majority of birds recruited into the breeding population.
A potential reason for the high mortality is the lack of sea ice in the area traditionally occupied by Cooper Island guillemots in winter. The unprecedented lack of sea ice over the Bering Sea shelf likely forced birds to occupy the ice edge in the Arctic Basin north of the Bering Strait, where prey resources may not be as abundant.
The 15 geolocators recently removed from returning birds will allow determination of the winter distribution.
The number of breeding pairs also declined due to the number of pairs maintaining nest sites but failing to lay eggs. Nonbreeding by experienced birds and established pairs has been extremely rare on Cooper Island but this year there are 20 such pairs. The presence of such birds, unable to initiate clutches after occupying a nest site, is an indication that overwinter or spring conditions caused both a decrease in the condition of returning birds as well as increased mortality.
Eggs will begin hatching in the third week of July and one has to hope fledging success will be high.
This field report is part of an ongoing series titled Arctic Change centered around George Divoky’s 44th field season studying Black Guillemots, sea ice, and climate change on a remote Arctic island off the coast of Alaska. To donate and support Divoky’s work on Cooper Island, visit the Friends of Cooper Island website.
Pigeon Guillemots are a coastal species that are locally common, meaning they are common in areas suited to their needs. You won’t spot them on sandy beaches, but in places with rocky outcrops and where they like to nest in inaccessible rocky crevices. To Lindquist, this speaks to the different survival strategies adopted out here: Common Murres nest in large colonies, seeking protection as group; Cassin’s Auklet's are nocturnal and nest in burrows; and, Pigeon Guillemots use the rocky crevices for protection while breeding. Image Credit: Julie Chase/ACCESS/NOAA/Point Blue
Pigeon Guillemots are a coastal species that are locally common, meaning they are common in areas suited to their needs. You won’t spot them on sandy beaches, but in places with rocky outcrops and where they like to nest in inaccessible rocky crevices. To Lindquist, this speaks to the different survival strategies adopted out here: Common Murres nest in large colonies, seeking protection as group; Cassin’s Auklet’s are nocturnal and nest in burrows; and, Pigeon Guillemots use the rocky crevices for protection while breeding. Image Credit: Julie Chase/ACCESS/NOAA/Point Blue
The Western Gulls are residents of Farallon Islands and they’re quite abundant. Unlike the other birds out here, they forage in the wild, but they also come very close to human activities and interact with people. Western Gulls are much less isolated than the other species studied on the islands. Image Credit: Julie Chase/ACCESS/NOAA/Point Blue
Kirsten Lindquist is the ecosystem monitoring manager for the Greater Farallones Association (GFA); she is also the birder for this ACCESS cruise. She’s awestruck by ocean creatures that live in such extreme environments. Image Credit: Julie Chase/ACCESS/NOAA/Point Blue
Common Murre are ubiquitous here, nesting by the thousands. While cruising through the area, we’ve encountered large rafts of them floating out in the open and the cry of a father Common Murre searching for his baby chick can be heard frequently. Image Credit: Jenny Woodman/ACCESS/NOAA/Point Blue
The Cassin’s Auklet live offshore, you won’t see them as they are not a coastal or near-shore species. They come on land at night to breed and nest in burrows underground. The rest of the year they live out in the open ocean. They are fans of krill, the small shrimp-like crustacean that lures so many critters to the region. “Since Auklets are a lot more abundant than Blue Whales, we can use Cassin’s as indicators,” says Kirsten Lindquist, birder on this ACCESS cruise. They are underwater flyers; some birds swim with their feet and keep their wings retracted underwater. Using their wings, Cassin’s and Common Murres fly underwater. Image Credit: Point Blue Conservation Science
Rhinoceros Auklet are similar to Cassin’s Auklet in foraging and nesting, but they are less abundant in the area. They eat fish, not krill, primarily what’s available. Juvenile rockfish are the preferred food choice, but they will eat larger anchovies, which can be problematic because they may be too large for chicks to consume. Image Credit: Farallon Islands Foundation
Click on the captions to expand and read more.
The sound is deafening — a symphony composed of 350,000 seabirds screeching and calling to each other. Ask a table full of scientists in the mess hall what it sounds like when you first set foot on the Farallon Islands and they answer in unison: cacophony.
The islands are home to the largest nesting colonies of seabirds south of Alaska.
Competition for real estate on the Farallons is minimal because each species has different needs. Pigeon Guillemots nest in rocky crevices and talus slopes, while the Common Murres find safety in numbers, perched atop steep cliffs and outcrops by the thousands. Rhinoceros and Cassin’s Auklets come on land at night and burrow underground to lay their eggs.
After decades of observations, scientists have learned a great deal about these creatures, but much of the research only occurs when the birds come ashore to breed in the summer. How do we know about birds that spend the vast majority of their lives out in the open ocean where few humans visit?
Some information is gleaned by sending teams on scientific expeditions like this ACCESS cruise, undertaken via a partnership between North-Central National Marine Sanctuaries and Point Blue Conservation Science. Wildlife observers spend most of each day conducting visual surveys, counting seabirds and marine mammals with a level of precision that is impressive to a non-scientist watching from the sidelines.
At various points each day, the ship stops to collect water and biological samples to understand food distribution in the region. By comparing the visual counts of animals with the samples collected, scientists can help determine predictable locations where food in the ocean lead to birds and mammals aggregating. Identifying where these hotspots overlap with human activity may help reduce negative impacts such as ship strikes and entanglements.
Adding tagging technology to these data sets enriches the picture even more.
A short sample of a time-depth recorder (TDR) dive profile of a single Cassin’s auklet. The different depths and durations of dives can tell scientists about prey availability and dive success. Image Credit: Point Blue Conservation Science
Researchers can combine tracking and dive patterns to show when birds are going to forage and where they’re finding food. The types of dives and how deep they’re going can tell you how deep the prey is, according to Kirsten Lindquist.
Lindquist is the ecosystem monitoring manager for the Greater Farallones Association (GFA); she is also the birder for this cruise and has conducted field work on the islands. “We only know food conditions when they are breeding,” she said.
According to Lindquist, data gathered over the years has revealed details such as clutch size, diet, nesting timing and success, but this information only reflects what is happening during the summer.
In Far from Land: The Mysterious Lives of Seabirds, Michael Brooke writes, “It can be quite rare for observers to see the birds actually feeding. Is this because the birds manage to catch enough food to last, say, a couple of days during infrequent bouts of gorging, or is it because much feeding happens at night when they cannot be seen?”
“How do you tell the story of fledging on into the next spring? Where are these birds going?” Lindquist asks. Breeding season is one window – it’s just a snapshot in time, she explains.
In other words, the lives of seabirds remain a bit of a mystery.
Geolocator (GLS) position estimates of a single Cassin’s auklet over an 8-month period, which made a movement south to Southern California in the winter of 2017-18. Image Credit: Point Blue Conservation Science
Jaime Jahncke, California Current Group director for Point Blue Conservation Science, points out that data from GLS tags on Cassin’s Auklets during the non-breeding season has shown that birds from the Farallon Islands disperse much farther than the scientists on the Point Blue team originally thought.
“A single bird can go as far south as Baja, California and others have gone as far north as Oregon,” said Jahncke. “This makes conservation efforts a real challenge.”
While breeding on the islands the birds are protected by the U.S. Fish & Wildlife Refuge. When foraging, they’re protected within the Sanctuaries. Discovering the birds range is extended after the breeding season puts these conservation scientists in uncharted territories, because they don’t know what threats these birds face beyond the protected boundaries previously studied, said Jahncke.
Elsewhere, observations are also captured in the field by scientists like George Divoky. Each summer, he lives alone on a barrier island in the Arctic with a small colony of breeding Mandt’s Black Guillemots. He visits all the nests daily, weighing chicks and collecting data. In spite of the longevity of his 44-year study, each season seems to bring new insights, especially as the technology aiding this work gets smaller, faster, and smarter.
When unexpected snow and cold in Alaska delayed the arrival of Divoky’s Black Guillemots in June, he looked at previous year’s data from geolocators and determined that they were most likely waiting in nearby Nuvuk and would arrive as soon as their nesting boxes were clear of snow, which they eventually did.
Every spring when the guillemots return, he removes the geolocators to download data about where the birds have been spending time over the winter. In addition to aiding his own research, this data is being used by several graduate students and organizations such as SENSEI (a French research group funded by BNP Paribas) seeking to better understand the impacts of climate change in the Arctic.
GPS track of a single Rhinoceros Auklet over a 4-day period, part of a collaborative project with Scott Shaffer from San Jose State. Image Credit: Point Blue Conservation Science
Using GPS or Geolocator (GLS) tags reveal different information. The GPS used on a Rhinoceros Auklet from the Farallon Islands offered a very detailed map of where the seabird traveled during one four-day period, whereas a GLS tag helped researchers map the places seabirds traveled from month to month during the non-breeding season. “One is more fine scale movements in a foraging area and one is less fine scale trying to get data over winter,” said Lindquist.
To scientists like Divoky, Jahncke, and Lindquist, technology may hold the key to a deeper understanding of the lives of seabirds where they spend most of their time — at sea.
Lindquist said, “I’m drawn to deep, untouched wilderness and the wild things that make their home there. The ocean has a lot of that close to shore.” She explained that they can leverage the number of years of seabird data and new information from technology to tell the story of the species and the pressures they are facing in a rapidly changing world.
Jenny Woodman, Proteus founder and executive director, is a science writer and educator living in the Pacific Northwest. Follower her on Twitter @JennyWoodman.
Common Murres on Farallon Islands. Image Credit: Point Blue Conservation Science
Common Murres in flight, some with fish. Image Credit: Julie Chase/ACCESS/NOAA/Point Blue
Common Murre are abundant here; many can be seen carrying fish on a return flight to the Farallon Islands, where hungry babies eagerly wait for their next meal. The islands — uninhabited by humans except for a small group of scientists — are nesting grounds for thirteen species of seabirds and six species of marine mammals that breed or haul out on the islands each year.
According to U.S. Fish & Wildlife service, the Farallons host the largest seabird nesting colony south of Alaska with numbers greater than 350,000 in the summer, including nesting Common Murres, Tufted Puffins, Pigeon Guillemots, and Western Gulls.
Just 27 miles west of San Francisco, these rocky islands weren’t always an ideal habitat for seabirds. During the California Gold Rush, a lack of agricultural infrastructure led hungry prospectors and entrepreneurial foragers to the Farallons for eggs, which pushed the Common Murre to the brink of extinction.
Over the years, a combination of exploitation from hunting and foraging to military uses left the island in a state of disarray. Feral cats and nonnative rabbits introduced by previous inhabitants obliterated many seabirds. Oil spills and pollution also took a toll on the habitat, which was established as a national wildlife refuge in 1909 by Theodore Roosevelt. Since the late 1960s, partnerships between U.S. Fish & Wildlife, NOAA, and Point Blue Conservation Science have helped to restore and maintain the Farallons for wildlife and research.
Computer imagery shows the topography of the seafloor of Greater Farallones National Marine Sanctuary and the steep drop-off of the continental slope west of the Farallon Islands. Image Credit: USGS/Woods Hole
We’re here on the second day of an Applied California Current Ecosystem Studies, or ACCESS, cruise. It is part of a long-term effort, now in its 15th year, to monitor and understand the oceanographic conditions, prey availability, and abundance and distribution of seabirds and whales in the region.
The data collected on these cruises, which take place three to five times per year, are used to help inform decision-making and research priorities in Northern and Central California National Marine Sanctuaries. ACCESS is a partnership between NOAA National Marine Sanctuaries and Point Blue Conservation Science.
Seabirds and marine mammals are drawn to the region by a process called upwelling. In the spring, strong winds move across the surface of the ocean circulating and drawing cold, nutrient-rich water from the deep ocean areas that lie below the edge of the Continental Shelf and Slope. This process is part of what makes these waters, according to NASA, “some of the most biologically productive in the world.”
When these nutrients reach the sunlight at the surface, the perfect environment is created for marine plant life — from phytoplankton to kelp forests. The plants, in turn, feed the wildlife.
Krill thrive in these nutrient-rich waters. “Its size is tiny, but its significance is colossal,” Mary Jane Schramm writes. “Krill – a shrimp-like crustacean – forms the basis of the marine food web for whales, seabirds, fish, squid, seals, and sharks throughout the world’s oceans.”
As we zigzag along the coast via predetermined transect lines, this productivity is evident in both the variety and quantity of life seen here.
The expert wildlife observers are armed with details to make each sighting even more exciting. When prompted, Dru Devlin, research associate for Greater Farallones Association, offers up a litany of fascinating details about the Common Murres, which nest on steep, rocky cliffs.
Common Murres on Farallon Islands. Image Credit: Point Blue Conservation Science
The female lays one large blue egg, which she sits on for the duration without nourishment. When the egg finally hatches, she takes off to replenish her strength for whatever lies ahead and the father steps in to take care of the baby chick. (In Far from Land: The Mysterious Life of Seabirds, Michael Brooke points out that seabirds generally only produce one to two eggs per year, which he adds is smart evolutionary strategy, because otherwise the ocean would be full of birds with nothing to eat!)
Murre chicks leave the nest, before they’ve fledged, meaning they haven’t grown flight feathers. When the time comes, the father and chick leap off the steep cliff and into the water below where the little one floats for up to two months, waiting for its flight feathers to come in.
Yesterday, we heard a cacophony of bird calls throughout the day; Devlin explained that we were hearing the father birds calling out to their chicks as they returned from fishing for food. Devlin concludes her explanation by asking me to imagine what it must be like to look for your baby in the midst of rough seas and large swells and I find myself, once again, awestruck by the tenacity of seabirds.
Black-footed albatross in flight. Image Credit: Julie Chase/ACCESS/NOAA/Point Blue
Pacific White-Sided Dolphins. Image Credit: Jenny Woodman/ACCESS/NOAA/Point Blue
In a very short period of time, I’ve seen so much. As a city kid from Philadelphia, my encounters with animals outside of zoos were limited to squirrels and pigeons, so much of these sightings are pretty big firsts for me. While everyone was busy deploying equipment on a side deck after breakfast, I ducked around a corner for a quiet moment and found myself alone with a pod of Pacific white-sided dolphins, playfully lingering alongside our vessel.
Observing these creatures is a rare treat made even better when accompanied by a team of biologists and wildlife experts to explain what I see and fill me with a sense of wonder for new favorites like the uncommon Common Murres.
Spotted Wednesday, July 4:
Common Murres
Sooty Shearwaters
Sabine’s Gulls
Herring Gulls
Brown Pelicans
Cassin’s Auklets
Blue Whales
Humpback Whales
Unidentified Whales
California Sea Lions
Jenny Woodman, Proteus founder and executive director, is a science writer and educator living in the Pacific Northwest. Follower her on Twitter @JennyWoodman.
A pair of nesting guillemots from 2011. Image Credit: George Divoky
A pair of nesting guillemots from 2011. Image Credit: George Divoky
30 nests with eggs–about half of the active nests! In recent years, few eggs have been laid in July, but not this year.
Adult survival is apparently as low as last year (about 75 percent compared to the long-term average of 90 percent). Unlike last year, there are a number of 3-yr-olds that fledged in 2015 and have reached the age when guillemots first breed.
Nonbreeding Peregrine Falcons occasionally stop by Cooper Island and are interested in both Black Guillemot adults and nestlings. This one was caught on a motion-sensitive camera as it hoped a chick might appear at the entrance. Image Credit: Goerge Divoky
While last year’s many widowed birds paired with their widowed neighbors (resulting in the decrease in nest sites) this year new birds are occupying the vacancies resulting from the increased mortality.
Guillemots typically don’t breed until their third year. There are even a few pairs this year with both members consisting of returning Cooper birds breeding for the first time.
Just finished the adult census as a Peregrine kept birds offshore or in sites for 2 days.
Getting the WeatherPort (which is basically a heavy-duty canvas structure, similar to a yurt) set up now — more later.
This field report is part of an ongoing series titled Arctic Change centered around George Divoky’s 44th field season studying Black Guillemots, sea ice, and climate change on a remote Arctic island off the coast of Alaska. To donate and support Divoky’s work on Cooper Island, visit the Friends of Cooper Island.
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