Farallon Islands

Cassin's Known-age /  by Michael Johns

One of the more exciting projects we conduct on the Farallones is the Cassin's auklet known-age study, which was first initiated in 1983. The birds are known-age because they are banded as checks, and once those chicks recruit into an unoccupied nest box we can gather valuable information on mate selection and retention, changes in breeding performance with experience and age, and signals of individual quality; all of which help managers better understand how individual contributions lead to population level changes. The work involves checking the contents of over 400 nest boxes distributed across the island, and taking various measurements of adult birds like bill depth, wing chord, and weight, which are used to determine body condition and sex. 

Photo taken through Point Blue Conservation Science | USFWS

April Showers /  by Michael Johns

This spring has been dominated by unsettled weather. We've been receiving a steady stream of moisture from the south, with descent downpours occurring every week. The weather makes for some dramatic early morning scenes, and has also been keeping the yellow flowers of the Farallon weed around for a little bit longer. 

Photo: Point Blue Conservation Science and USFWS

50 Years of Bands /  by Michael Johns

It's been 50 years since scientists from Point Blue Conservation Science (then Point Reyes Birds Observatory) began a continuous monitoring effort on SE Farallon Island. Some of this work includes banding certain species of seabirds to learn more about their movement patterns, survival and mortality rates, population status, and individual breeding behavior and success; all important information guiding management decisions and tracking the potential effects of climate change. Point Blue has amassed an impressive sample of banded birds since work first started in 1967, totaling nearly 125,000 individuals as of 2016. The graphic below illustrates the total bands put out by year and cumulatively since 1967 for 8 target species. 

Navigating With The Sun /  by Michael Johns

One of the easiest ways to study basic life-history and behavior of seabirds is to outfit them with devices the passively record data for you. The tricky part is getting those devices back in order to download and analyze those data. So far this season, we have recovered 19 geolocator tags that were secured to the legs of Cassin's auklets breeding in artificial nest boxes last year. These tags are designed to be very small and light, and have zero affect on the breeding performance and survival of birds that carry them. Geolocators record ambient light levels experienced by the bird as it flies around it's environment. These light level recordings are later used to estimate roughly where the bird was twice a day throughout the deployment period, using the timing of sunrise and sunset (which varies depending on longitude) and the duration of day-length (which varies by latitude). The photo above shows a row of tags calibrating in the sun on SE Farallon Island. 

Noting The Weather /  by Michael Johns

For roughly 50 years now, researchers on the Farallones have recorded daily island weather observations that include the wind intensity and direction, air temperature, and sea conditions. And for roughly 50 years the instruments used to collect these data haven't changed much. This long time series of direct weather observations provides information on meteorological and oceanographic patterns that impact the productivity and success of species that breed on the island, from short-term phenomena such as El Nino, to long-term trends associated with climate change. Recently, strong gusts from the Northwest have been tipping the anemometer needle beyond the 30 knot mark, a good spring wind to drive the upwelling.

Watching The Sea /  by Michael Johns

Well, I'm back on the Farallones for another seabird season, and so begins another series of stories from the field. I've decided this year to briefly describe all of the different projects we do out here during the summer. From simple tasks such as taking the weather, to complex tasks like keeping track of 400+ Cassin's auklet nest boxes. To kick off this series, I choose one of my favorite morning rituals, "sea watch". Every morning, the designated sea watch person (Katie in the case of the photo above) sets up a 50x spotting scope on the front porch of the PRBO House where we live, orients it southwest over the marine terrace, and watches the sea for a standard 5-minute period. The idea is to count any pelagic species other than the ones that breed on the island that pass through the fixed field of view, to get a sense of long-term changes in the timing and abundance of seabirds that use the waters around the Farallones. 

Visualizing Effort on SEFI /  by Michael Johns

As the name would suggest, long-term datasets take a long time to develop. Not only does it take a continuous supply of resources to support the work, someone has to physically go out every year and collect the data. To visualize the time investment and sheer number of people required to collect 50 years of seabird and marine mammal data, I designed this circular bar plot, illustrating the extreme commitment by some and small contributions by many over the years. It depicts the total number of days spent on Southeast Farallon Island (SEFI) by current and former staff and interns of PRBO (now Point Blue Conservation Science). Each concentric circle radiating from the map of SEFI in the center represents an additional 500 days of service, with Pete Warzybok in the lead at over 2,000 days! To keep the plot from getting too cramped, I narrowed the number of names displayed to just partial or full PRBO associates with more than two months spent on island, so this plot excludes many more island residents affiliated with various agencies, contracts, and universities, as well as people with brief stints – sorry if that applies to you. The graphic was created entirely with the ggplot2 package in R, aside from the border and line below the title that were added later in Photoshop. A high resolution 16 x 20 .png file of the graphic can be downloaded here: DOWNLOAD FILE 

Data Into Art /  by Michael Johns

R is an open source statistical computing and graphics platform, where tasks are implemented through a coding language entered by the user. The flexibility of R is limited only by the collective ability of its community of users to dream up new functions and functionality; which means its potential is basically limitless. It has become the environment for researchers to carry out statistical analyses and produce publication-ready figures. 

Inspired by some cool new plots floating around the internet that mimic Joy Division's "Unknown Pleasures" 1979 album cover, I created the above image of Southeast Farallon Island using a new R package developed to better visualize changes in distributions over time. The image depicting the the change in elevation across a range on longitude for each line of latitude was produced with the packages ggplot2 and ggridges, using a dataset containing elevation information of the island at equally spaced points of lat and long. An example of using R for more than just stats and figures, creating something that could even pass for art. 

Download this .asc file and use this code to recreate the above image in R. 

Here's another way of looking at the same dataset using geom_polygon in ggplot2, where each polygon is colored by latitude. This shows the vertical relief of the island from the perspective of the waterline, looking north. The tallest peak at just over 100 meters is the top of Lighthouse Hill. The second largest at just below 75 meters is Maintop, which is separated from the main island by a very narrow channel. 

Seasonal Visitor /  by Michael Johns

I'm told that at least one barn owl is a commonly observed winter resident on the Farallones, possibly feasting on seabirds in a inconspicuous location during the summer months and emerging once the noise of the breeding western gulls subsides in the fall. This owl was regularly roosting on one of the three trees on the island outside my bedroom window before I left for Fairbanks.

It's August /  by Michael Johns

Change is in the air on this wind swept heap of rock. Warm moist air from the south has been pushing the fog offshore and replacing it with rolling waves of stratus clouds, creating some contrasting pastels in the morning light. To provide a bit of context for this photo, on the left is the "PRBO House", where we live and work. On the right is the "Coast Guard House", an identical twin to the PRBO House used sporadically by the Fish and Wildlife Service when on island. 

Catch Of The Day /  by Michael Johns

Part of the work we do includes monitoring the diet of several seabird species that serve as indicators of fish populations in the Gulf of the Farallones. This involves sitting in arm chairs near nesting areas or in blinds with a pair of binoculars and watching birds fly in with bill loads of fish. Species such as pigeon guillemots and common murres deliver a single fish held in their bill with every foraging trip, so we can identify the type and size of each prey item fed to the awaiting chick. Earlier in the season, we were seeing a lot of juvenile rockfish in their diet, and it turns out pinnipeds like to take the adults too. This Steller's sea lion was seen tossing a vermillion rockfish at the surface, shredding it into more manageable pieces while the western gulls snatched up the smaller bits. 

Natural Fireworks /  by Michael Johns

We do a fare bit of night work out here on the Farallones, from banding Ashy Storm-petrels to access population trends to netting Rhinoceros Auklets to collect diet samples. On this particular night, on our way back to the house after conducting cave surveys for an endemic cricket species, we noticed the waves in Maintop Bay were giving off tiny flashes of bright blue-green light. It was bioluminescence, a natural emission of light produced by living organisms, in this case by microscopic phytoplankton called dinoflagellates. The agitation of the surf causes them to give off this glow, lighting up the shoreline with a natural display of fireworks. Although not visible in this photo, I can assure you the sparkling waves evoked several "wows". 

History /  by Michael Johns

Southeast Farallon Island has an eclectic mix of old structures from the days of the Russian fur trade, the Gold Rush, and the lighthouse keepers families, that have been repurposed for modern use. This old stone building for example now serves as our wood shop, or "Carp Shop" as we like to call it. 

Final Light /  by Michael Johns

Summer weather offshore of Central California typically falls into three categories: wind, fog, or both. This often catches tourists off guard, where people expecting a warm July whale watch outside the bay end up wearing shorts and a t-shirt on a 5-hour long cruise in cold pea soup fog. Occasionally, however, the fog vanishes and the wind subsides, setting the stage for a fleeting phenomena of pleasant weather. On these rare clear evenings, usually towards the end of summer and into fall, lofty stratocumulus clouds paint the sky brilliant shades of sunset colors during the final minutes of remaining light. 

They Grow Up Fast /  by Michael Johns

After a two week hiatus from the island, I arrived yesterday to the signs of change. The landscape on the Farallones is now significantly drier, the gulls less intense in their areal assaults, and many of the seabird species we monitor now have chicks big enough to leave the protection of their parents and start life as individuals. The common murre chick pictured here is close it 3 weeks old, and will soon follow the male parent through a busy colony, past a dense pile of hauled out sea lions, and over a steep cliff into the sea. Thousands more murre chicks will do the same, in nightly mass fledging events that take place just after dusk. These chicks will then be reared by the male at sea until they are big enough to fly and forage on their own, bringing the chick to the fish instead of the fish to the chick. 

Stormy Netting /  by Michael Johns

The wind has finally dropped and the moon is close to new; prime conditions for working the mist net. We've started a third round of Ashy Storm-petrel netting to put out more bands for a long-term mark-recapture study, and PIT tags for a graduate student's PhD work. Last night we opened the net just after 1030PM to a flurry of activity, catching 6 birds within minutes. Red filters on our headlamps help to minimize handling stress to the palm-sized seabirds, while we record wing chord, brood patch status, mass, and secure the band and tag. The pace slowed by the second hour, forcing us to quit an hour early due to a lack of activity. The night was slow, but the stars and a freak lightning show over San Fransisco kept things interesting until it was time to head back to the house.  

The Other Inhabitants /  by Michael Johns

Along with 13 species of breeding birds, the Farallones are used as a haul out and pupping site for 5 species of Pinnipeds. For those of you unfamiliar with the term, Pinnipeds are the "fin-footed" marine mammals, a taxonomic distinction that describes all of the seals, sea lions, and walrus. Northern Elephant Seals, Fur Seals, Steller Sea Lions, California Sea Lions, and Harbor Seals can all be seen in various numbers and reproductive stages on the island throughout the the year. They offer a visual reprieve from many hours of waiting for birds to stand off their nests and reveal what's brooding underneath. These two massive adult male Steller Sea Lions were occupying the same territory, and likely had just finished an epic battle that must have ended in a stalemate. True Chewbaccas of the sea. 

Eggs, So Many Eggs /  by Michael Johns

Common murres, pictured here, are some of the most devoted parents on the island. Although their mint green eggs are laid on precarious rocky cliff ledges, few are lost given intense parental care and attention. Tucked beneath soft breast feathers and wedged between a pair of webbed feet, common murre eggs withstand driving wind and harsh weather for roughly 28 days before a chick eventually emerges from within. We have been waiting and watching patiently from blinds above the colony for weeks now for this event to happen, with the first hatches scheduled to occur sometime in mid June. 

When Night Falls /  by Michael Johns

Somewhere between four and nine thousand ashy storm-petrels breed on Southeast Farallon Island, roughy half of the world's population. These sparrow-sized seabirds are tiny versions of more familiar open ocean wanderers like shearwaters and albatrosses, and like their relatives they brave extreme oceanic storms in a truly pelagic lifestyle. Ashy storm-petrels only arrive on colony after dusk and depart before dawn, and are almost never seen on island during the day. So in order to study this species, you have to forgo normal working hours and venture out into the field at night. During lulls in the spring winds, we head out just before 10PM to suitable storm-petrel breeding habitats and set up a long wall of fine mesh netting called a mist net. Calls of ashy storm-petrels are played with a loud speaking near the net to attract unsuspecting birds. Storm-petrels caught in the mist net are then measured, weighed, and banded with a small metal numeric leg band before being released; part of a mark-recapture study aimed to arrive at a more accurate estimate of the breeding population on the Farallones. Along with the joys of working with such an incredible seabird species, on clear nights we are also treated to a dazzling display of our own galaxy.