A Dependency on Glass

As some of you may or may not know, we seabird biologists here on SEFI tend to spend a lot of our time working in the various blinds around the island. For a quick description on the different blinds around the island, check out this blog post from 2007. What do we do in these blinds? Well, the majority of the time we are looking through binoculars or spotting scopes at a number of different Common Murre and Brandt’s Cormorants breeding subcolonies. We record individual attendance at nest sites, we assess nest condition (for the Cormorants; the Common Murres don’t have nests), we check to see if there are eggs or chicks present, and of course, we spend a long time trying to read the tiny metal and or plastic bands that are on the birds legs. Thankfully, all of this can be accomplished from the safety of a well secured small wooden box perched atop a precipice which ensures that we do not flush any of our feathered friends from their respective roosting spots. 

The view of Corm Blind from the water: our safely secured box on the cliffside. Photo RJ Roush.

How are we able to do all this from a far distance away? With the use of our trusty scopes and binoculars, of course! Well, I’m sure some of you are thinking, “So? What’s the big deal?” And herein lies my point du jour: we are in a great debt to those glass objects which allow us to visually cover great distances. We often fail to acknowledge this awesome tool we have; we take it for granted. Without the small piece of technology that is the lens—allowing us to magnify images 10-60x and beyond—reading bands on some of these species would be downright preposterous. 

An unusual upside-down view of West End from the lens of our spotting scope. Photo RJ Roush.

               As I sat up in the Corm Blind one chilly evening, I started mulling over a scenario in which we would have to read a metal band without the use of any kind of glass. First off, you would need to ditch the blind all together. The relative comfort that the blind offers is nice and all, but you can’t read a band with the naked eye from a few dozen meters out. This means you need to get close to the bird, very, very close. The numbers printed on the bands for the Brandt’s Cormorants are roughly size 22 font in a word document and the Common Murre numbers are closer to size 12.

               Our number one priority is to not disturb the birds while studying them. After all, what good is getting a read on a band if the individual wearing the band abandons it’s nest site? So, we need to get close enough to read the band number without flushing the bird. A simple concept, but these birds are very observant of their surroundings and are quick to fly off if they see or hear something unusual and an odd biologist walking into their colony would clearly count as something unusual. So, we turn to stealth. Not the ninja kind of stealth where you hide in the shadows—there aren’t many human sized places to hide—no, you will need to hide in plain sight of the birds. The easiest way I can think to do this is to move extraordinarily slowly. We’re talking molasses in the Arctic slow; glacially slow. I can picture it now. Crawling along on the lice-ridden (Cormorants are known to harbor countless lice in their nests), muddy ground for the better part of a day to read a few digits on a single band. You are the sea-soaked soil which the birds sit on; you are the Farallon Weed which covers the island; you are nothing more than a stone that happens to be on the move.

               Your normal field work clothes, though thoroughly covered in dirt and bird excrement, will simply not work, either. The birds will likely take notice of a strange humanoid shaped object advancing toward their home. The Brandt’s Cormorants are unlikely to let you join the party unless you are wearing the correct attire, so a disguise is of utmost importance. Now, I have thought about sewing together a cormorant suit for just such an occasion, but after further consideration, I decided that would be ridiculous. So, instead of a human-sized Cormorant, you will need to do more than just think you are the soil, vegetation and stones of the island, you will need to don them as a carefully crafted cloak to conceal your identity. In other words: camouflage.

So, how are we doing? Covered head-to-toe in Farallon Weed and soil and the like, crawling slower than slow towards a birds nest with the intent of reading the size 22 (hopefully) or size 12 font engraved on the metal band around it’s ankle over the course of hours or perhaps even days. Now that would be some serious dedication to the seabirds. I, for one, am wholly overwhelmed with gratitude for the fine glass that we utilize whilst on the job. As both a budding bird biologist and a photographer, I pay homage to the tools that I and my peers use on a daily basis on the island. 

A few of the "tools" that I use on a daily basis on SEFI. Look at all that glass! Photo RJ Roush.

These few items allow us to not only gather the all-important data which helps us better understand the organisms and the systems which they interact with, but it allows us to bring these creatures closer to us. It allows us to see them up close, to observe them, and when taking photos, to share their beauty with countless others.

Much thanks to you, glass.

Taking photos of wildlife at sunset. Photo credit to Emma Kelsey

words by RJ Roush

What do gulls eat?

Western Gulls.  Photo: RJ Roush

‘Much that is good and all that is evil has gathered itself up into the Western Gull.
…cruel of beak and bottomless of maw…this gull asks only two question of any other living thing: First, “Am I hungry?” (Ans. “Yes”) Second, “Can I get away with it?” (Ans. “I’ll try).’ 

So wrote naturalist William Leon Dawson in The Birds of California in 1923, and a brilliant demonstration of that bottomless maw is found in the SEFI Gull JuJu Archive.  The Archive, cherished for posterity in a tin box in our data room, is a random collection of strange and interesting objects brought to Southeast Farallon Island by gulls.

 

The Archive.  Photos: Scarlett Hutchin

The gulls don’t often carry things around in their bills for long, preferring to swallow them first and ask questions later, so it’s reasonable to assume that everything in the Gull Juju Archive has probably been swallowed and regurgitated by a gull at least once.  Things like a six inch plastic toy hammer, a baby doll leg, a rubber tortoise, a golf ball, a set of vampire teeth, a collection of large fish hooks and four jelly beans still sealed in a bag inside a plastic Easter egg.  

There are fragments of driver’s licences and credit cards, a key, a few toy cars, a pacifier, Lego blocks, marbles, a balloon that reads ‘happy f***ing birthday’, a drinks stirrer from a restaurant in Newport Beach and another from Denver.

And if none of these were impressive enough evidence of the awesome power of the gull’s gullet, SEFI biologist Pete Warzybok tells me that not only has he seen a Westen Gull catch and swallow a flying Rufus Hummingbird, he has also seen one regurgitate a tennis ball.  Yes, seriously, a tennis ball.

Western Gull.  Photo: Scarlett Hutchin

Pinniped Necropsies on the Farallones

(Warning some photos may be a bit graphic)

PRBO Conservation Science, in collaboration with other agencies, performed pinniped (seal and sea lion) necropsies during the 2012-2013 winter season on SEFI. All carcasses were recovered in a safe manner and with minimal disturbance to live pinnipeds. Aborted California Sea Lion (CSL) fetuses were first noticed on the 24 Feb 2013 and by 15 Mar 2013 a minimum of 85 had been documented. Tissue samples of brain, liver, bile, stomach contents, feces/meconium and urine were collected and tests were run for traces of Domoic Acid (DA); a common cause for CSL strandings. One side effect of adult female CSLs affected with DA intoxication is to abort their fetuses. The placentas of pregnant females act as reservoirs for DA and even if the dams have cleared themselves of DA (through urine excretion), it continues to circulate within the placenta/fetus resulting in abortion. Below is a series of photos showing how one of the aborted fetuses was necropsied and photographed with labels in order to document potential causes of death.

Domoic Acid is introduced via the food web to marine mammals and birds through a variety of intermediaries, including both pelagic and benthic organisms that feed on toxin-producing Pseudonitzschia, an algae and the DA source. High numbers of Pseudonitzschia have often been associated with the end of upwelling events or weak upwelling events during warm years along with low concentrations of macronutrients. In both central and southern California, the occurrence of Pseudonitzschia blooms is also suggested to be tied to shorter term climate events such as ENSO and possibly also to phenomena on time scales of the Pacific decadal oscillation (more on DA and its bioaccumulation can be found here: http://channelislands.noaa.gov/focus/dom.html .)

Depiction of bio-accumulation of Domoic Acid up the food chain. Schematic taken from Channel Islands National Marine Sanctuary website.

Microscopic view of the diatom Pseudonitzschia taken from NOAA.gov

 With that said, all samples collected from the necropsied pinnipeds on SEFI resulted in below detectible levels for DA. In re-evaluating the circumstances and taking into account the recent increase in stranded yearling CSLs in Southern California we believe the cause of the aborted fetuses may be related to lack of prey items. In Southern California large numbers of dehydrated and emaciated sea lions are stranding themselves; causing rehabilitation centers to reach carrying capacity (a link to an online news article with more detail can be found here: http://www.nbclosangeles.com/news/local/Sea-Lion-Pup-Strandings-southern-California-investigated-201503511.html ). Agencies involved in monitoring this population believe that the sea lion’s major food item, schooling fish like anchovies and sardines, are currently absent from the ecological system (link to NOAA website with more details to numbers associated with strandings: http://www.nmfs.noaa.gov/pr/health/mmume/californiasealions2013.htm ). Similarly, if pregnant female CSLs are not able to find sufficient food they may abort their fetuses in response to not meeting the energy requirements needed to carry their pups to full term. We suspect this is the reason for the aborted pups seen on SEFI this past winter season.

Rehabilitation center full of yearling California sea lions that stranded from dehydration and malnutrition. Photo taken from wired.com

Figure comparing live California sea lion stranding over the last 5 years county. Purple bars represent 2013 numbers which are significantly higher than all other years. Figure taken from ecowatch.com.

 Mobile marine mammals are considered to be good coastal sentinels for signaling remote or offshore biotoxin events and by examining carcasses there is increased knowledge of mortality rates and causes which allows for a better understanding of population threats and pressures. Information gained includes complete pathology to investigate diseases and parasites, reproductive biology and life history data, pollution, human interactions and normal biology and physiology parameters. These types of sampling opportunities also help validate and increase understanding and interpretation of data collected from wild populations; especially individuals like marine mammals which are not readily accessible.  PRBO will continue to monitor the CSL population as the pupping season approaches in order to aid management decisions.

Pulmonary "pluck" of an adult California sea lion to examine the trachea, primary and secondary airways of the respiratory system, lungs and heart.

California sea lion heart removed from the thoracic cavity.

Contents of the abdominal cavity in an adult California sea lion. Notice yellow splotches on organs - results from tissue collected also confirmed cancer.

California sea lion spleen with discoloration and abscessed growth. Results indicated this animal had cancer.

Necropsy on a fresh dead northern elephant seal weaned pup. Cause of death was likely due to being crushed by an adult male.

Life in Boxes and Burrows

         

From March through August, Southeast Farallon is bustling with seabird activity, some more obvious than others.  The presence of the Western Gulls is undeniable, and it is pretty hard to miss the 250,000 or so Common Murres milling about as you approach the island.  But some species here on the island, being more reclusive and mysterious, don’t make their nesting presence as obvious. One such species is the Cassin’s Auklet.  They nest primarily in burrows and rocky crevices underground and come and go from the island only under the cover of darkness.  Luckily for us, they can also be found nesting in little wooden boxes with PVC pipe entrances and shaded roofs, which are scattered around the island, tucked in among the Farallon weed, lavatera and rocks. 

Cassin’s Auklet in a nest box, photo courtesy of Annie Schmidt.

         PRBO researchers began building and installing these artificial nest boxes in the early 70’s in order to provide additional nesting habitat and to make it easier to monitor the nesting phenology, breeding success, and chick growth rates of the auklets. Since then, the use of artificial nest boxes to monitor the breeding biology of burrow nesting seabirds has become a widely embraced technique.  But, for those of us researchers who depend on these nest boxes for our monitoring purposes; it is important for us to know that the boxes are, indeed, providing an adequate environment for the birds nesting within them.  I am here on SEFI to help PRBO and FNWR consider just that.

A Cassin’s Auklet nest box with shade cover.

Environmental temperatures on the Southeast Farallon Island were exceptionally warm during the 2008 and 2009 Cassin’s Auklet breeding seasons.  These anomalously warm temperatures meant that the artificial nest boxes turned into little hotboxes, which was distressing to some of the auklets nesting within.  In 2009, to help mediate this problem, PRBO researchers created shade structures for all occupied nest boxes and started a pilot study to better understand the differences in temperature experienced by the auklets in artificial and natural burrows.  Initial results showed that natural burrows were significantly cooler than nest boxes but putting shades on nest boxes decreased the nest box temperature notably.  Since 2009, all nest boxes with auklets nesting in them are covered in shades. 

The goal of my project is to take this study one step further.  I want to see if the adult auklets in nest boxes are able to control egg temperature when nest box temperatures are elevated, and how this may affect their hatching success.  

Reaching into an auklet home to switch out an egg.

For my project, I put devices that recorded temperature in hollow artificial Cassin’s Auklet eggs.  I then put the artificial egg in the auklets nest for a couple days to record egg incubation temperature.  The goal of the project was to compare the incubation temperature of auklets in different nest types- natural burrows, shaded nest boxes, and unshaded nest boxes.  Once I have chosen the nests where my artificial eggs were to be deployed, I diligently babysat the auklets real egg in a poultry incubator while the temperature loggers were deployed for seven days. 

 

Cassin’s Auklet eggs, safe and warm in the incubator.

I started my study a year ago and successfully made three deployments of egg temperature loggers during the 2012 auklet breeding season.  Based on my results so far, I have found that the eggs in artificial nest boxes are significantly warmer than those found in natural burrows that there is a significantly correlation between burrow habitat temperature and egg temperature.  However, these variations in egg temperature do not seem to significantly affect reproductive success of the auklets.  In other words, the nest habitat conditions in the artificial nest boxes may be warmer than in natural burrows but this doesn’t seem to be having negative effects on the overall breeding success of the birds.  My sample size is small enough thus far that it is difficult to say for sure though.
 

An artificial egg, ready to go inside a Cassin’s nest box.

The artificial eggs and wire pulling lubricant.

Beyond the science, this study has also given me the opportunity to learn about a lot more than just Cassin’s Auklet incubation temperature.  How do you make a fake Cassin’s Auklet egg?  You ask an art student (many thanks to Kat McKinnon and Philip Priolo of the San Jose State University art and industrial design departments!).  How do you incubate a Cassin’s Auklet egg?  You follow the directions for incubating quail eggs in the incubator package instruction manual.  How do you make a fake egg feel realistic enough so an auklet will want to incubate it without interfering with the temperature of the egg?  You fill it with wire pulling lubricant (don’t know what wire pulling lubricant is?  Don’t worry, I didn’t either until recently). 

This project has also given me the amazing opportunity to spend the season participating in all the other seabird studies that are carried out on this SEFI.  I have learned so much and made some wonderful memories out here.

I just arrived on SEFI for my second season deploying Cassin’s Auklet eggs, in which I hope to increase my sample size and get a better idea of the differences in incubation temperature between natural and artificial nest habitats and how the auklets may mitigate for this.  It is our hope that the results of this study could lead to the design and implementation of new and improved nest boxes of the Cassin’s Auklets on SEFI.  In the meantime, I am so happy to be back out here on this incredible island and I look forward to whatever the season has in store!

Emma Kelsey

PRBO research assistant and graduate student at San Jose State University