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On 24 July 2009 I returned to the Western Kingbird nest site that we profiled in our 18 July piece entitled, "At the Nest: Western Kingbird Photo Essay." As expected, three recently-fledged nestlings were found clustered together on the utility wire just a few meters from the nest shown in that post. I spent more than an hour enjoying the show as the youngsters made numerous short flights on uncertain wings and returned to the wire with all manner of clumsy landings. All the while, the two adults came and went in an effort to supply enough food for these three appetites with wings.
At first, the young kingbirds remained rather stationary on the wire. They chipped and chattered incessantly, as if their parents needed to be reminded that they were hungry. They also preened and stretched their stubby wings often and occasionally flapped their wings hard enough to briefly lift off the wire.
After several rounds of feeding, the adults began landing about 10-15 meters away from the juveniles. The adults would then chatter loudly and flutter their wings. This seemed to be a signal, for each time they engaged in this routine, one or more of the young kingbirds would take to the air and fly over to join the adult. By the time I left, the young birds were moving about almost continually and venturing farther and farther away from the nest site. According to the homeowner (a Schwan's customer of mine), the birds moved across the road later that evening and never returned to the wires near the nest.
Of all the behaviors I observed, I was most fascinated by the pugnaciousness of one of the young birds. At one point, a molting Brewer's Blackbird flew in and landed on the wire not far from the three youngsters. Kingbirds are aptly named because they rule their domain. They are absolutely fearless when faced by potential predators and other intruders and highly aggressive in defending their territories, nests, and young. Shortly after the blackbird landed, one young kingbird took flight and attacked the blackbird, flushing it off the wire and causing it to leave the area. It was quite impressive to see a young bird--which was perhaps a day or two out of the nest and barely flying--go after a much bigger and older bird...and emerge victorious!
The nearly two hours (two visits) I spent watching this family group was both entertaining and educational. All fledgling birds seem to possess a certain charm, thus it's hard to resist watching them come of age. It seems a wonder that these birds, which were fuzzy, partially-feathered nestlings a week earlier, are now fully-feathered and flying about. During the latter visit, it was clear that I was there on the day when this family was poised to leave the nest area. That process seemed to unfold right before my eyes. I returned again on 30 July 2009 and, as I expected, the family of Western Kingbirds had moved on. In the coming weeks, the three young kingbirds will complete their molts and with full wings and longer, more perfectly-shaped tails, they will embark on their first fall migration.
All photos taken by Dave Irons
Every once in a while we find ourselves in situations where we ask, is this really happening... to me? Yesterday will certainly not fade from memory quickly. There I was, diving into another day of plotting out features and functionality for the upcoming website release, and a Great Blue Heron walks into the BirdFellow office, unannounced. Our office is in a waterfront cabana at the east end of Oswego Lake, a few miles south of Portland, Oregon where, ironically, the Great Blue Heron is the official city bird. Close-up views of waterbirds are a daily occurrence, but this is the first bird to actually come in for a visit.
Once inside, the juvenile heron made a break for the kitchen and then dropped its payload in front of the dishwasher. Perhaps embarrassed by its bad manners, it headed for cover in the back room. Oh no, I thought, is there more? Quick, where is the heron diaper when I need one?
I grabbed my iPhone and nervously tracked it into the bathroom. Phew, at least we're in the right place now, I thought. But, wait! The lid is down. Startled by my approach, the bird hopped around anxiously, so I decided to back off. Within a few moments, the heron walked out of the bathroom and into the back office. I approached it again and this time it took flight. My mediocre "flight shot" skills were of no use as I was completely frozen by the sight of this huge bird--with a six-foot wingspan--flying around in a 10 x 12' office space. I had to scramble out of the way as the bird flew up and over the desk and lamp. Quickly, I decided to outflank the fowl by hiding in office supplies. Camouflaged by the fax machine, I had time to consider my next approach. How am I going to get this bird out of here?
But then, as if the Persian rug was as natural as a flooded meadow, it confidently walked towards to the door, back outside, and took flight. As I watched the bird fly across the bay, I thought to myself, does anyone else who is watching this Great Blue Heron fly right now know that it just whitewashed the headquarters of the only birding social media company for 900 miles?
We've decided to make a contest out of permanently titling this piece. We invite you to offer up your own creative headline (keep it clean) for this episode and post it as a comment to our website. We will choose the top three, the winner will see their entry become the ongoing headline for this article. The top-three entries, as determined by BirdFellow staff, will also receive BirdFellow.com wearables provided their posting includes their name and a usable e-mail address.
A half century ago, seeing a Western Kingbird in Oregon's Willamette Valley was a rare treat. Even in the drier southern reaches of that valley--around Eugene, Oregon--G.W Guillion (1951) reported encountering no more than 1-2 per year. Over recent decades, Western Kingbirds have become an increasingly common sight in this section of the Willamette Valley (Scheuering 2003). In the narrow valleys and pasturelands that reach into the foothills of the Coast Range southwest of Eugene, one can now expect to encounter a nesting pair of kingbirds every mile or so. While most clutches of Western Kingbirds fledge by the end of June (Gamble and Bergin 1996), some local adults can still be found feeding rapidly growing nestlings well into July. I encountered such a nest on 17 July and spent several minutes taking pictures and observing the comings and goings of the two adults, as well as the in-nest dynamics of the youngsters.
One of the expected things I noticed about the nestlings was an apparent pecking order. As seen in the image above, the middle bird (from my viewing angle) seemed determined to keep its head held higher than those of the other two birds. During the entirety of my visit, it had its neck craned out so that the tip of its bill would be higher than the bills of the other two birds. It kept up this behavior even during the long intervals between feedings. When one of the adults returned with food, this bird seemed particularly aggressive in its effort to get fed. From my vantage point, it was difficult to see which nestling was being fed and in what order.
According to Gamble and Bergin (1996), adult kingbirds feed just one nestling per nest visit. I suspect that bird craning its neck was getting fed with greater frequency than the other two. It appeared to be further along in in its development, both in terms of size and feather acquisition. Notice that the yellow on its underparts looks completely feathered with little exposed down. Conversely, the barely visible nestling to the left of this bird remained hunkered down in the nest and was not observed holding its head high and bill open like the others. It seemed to be a bit smaller than its siblings. Based on their feather development, these birds likely hatched about 10-13 days before this observation and this species typically fledges about 16 days after hatching (Gamble and Bergin 1996).
While the hatchlings were working things out in the nest, the adults came and went in a highly routinized manner. One adult would assume a "lookout" position on the wire about 2-3 meters from the nest, while the other adult was off capturing insects to feed the young. The lookout bird sat rather stationary, always in the same spot, only occasionally reversing its position on the wire so it would be facing the opposite direction. It remained unagitated and silent even when I was present. After several minutes of calm the lookout bird would suddenly start chattering, hovering, and frenetically hopping about on the wire and within seconds the feeding adult would come flying in to the nest. After the feeding adult filled the bills of a nestling, it would sit on the lip of the nest for a few seconds.
Satisfied that the youngsters were fed and that the feeding adult could now assume the lookout position, the lookout would leave its post and head off to hunt insects. As soon as it flew off, the feeding adult quickly moved into the same lookout position and waited quietly until the next exchange. I watched this exchange routine several times and in each case the lookout adult would commence its chattering before the other adult came into view. On one occasion I was able to spot the feeding adult almost immediately after the lookout bird started chattering and it was still over 50 meters away from the nest. Whether the lookout's chattering is a response to a visual or audio cue, I don't know, but the lookout would usually start chattering a good 5-6 seconds before the other adult arrived at the nest.
Like most young birds, these kingbird nestlings display bright yellow at the corners of their gapes and the insides of their mouths are bright orange-red (see image below). Many sources explain that the bright yellow gape mostly serves as a target of sorts for the feeding adult, particularly at low-light nest sites. Studies further suggest that the bright gape coloration may trigger the feeding instincts of the adults. Similar research also showed that if the gape color was reduced or artificially altered, birds with the brightest yellow gapes were fed more frequently (Dan Gleason pers. comm.). Other sources suggest that the intensity of the red/orange inside the mouth may be an indicator of the health of the nestling and may also affect the amount of food that the adults allocate to each nestling (Saino et al. 2003).
Among those who have experienced the combination of beauty, grace, and utter fearlessness of Western Kingbirds, this species generally ranks high on their list of favorite birds. Kenn Kaufman was so enamored with this species that he used it in the title of his book "Kingbird Highway." In chapter one he describes how this species instantly became his "favorite bird" shortly after his family moved west to Wichita, Kansas. For Kaufman, the fact that this bird had "Western" in its name signified that he must be in the West.
If one has the good fortune to live or at least travel in western North America during the spring and summer months, this species is a common sight. Whether they are heard chattering overhead, seen perched on a fence wire, building a nest on utility pole, or teed up on big sagebrush, Western Kingbirds are a source of joy for those of us who inhabit their range. They are no longer a surprise when I find them near home, yet I'm thankful that they have become a more common part of my local avifauna.
Gamble, Lawrence R. and Timothy M. Bergin. 1996. Western Kingbird (Tyrannus verticalis), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/227.
Guillion, G.W. 1951. Birds of the southern Willamette Valley, Oregon. Condor 53:129-149.
Kaufman, Kenn. 1997. Kingbird Highway. Houghton Mifflin Co. New York, NY.
Saino, Nichola, Roberto Ambrosini, Roberta Martinelli, Paola Ninni, and Anders Pape Moller. 2003. Gape Coloration Reliably Reflects Immunocompetence of Barn Swallow (Hirundo rustica) Nestlings. Behaviorial Ecology Vol 14 No. 1:16-22.
Scheuering, Rachel White. 2003. Western Kingbird. Pp. 395-397 in Birds of Oregon: A General Reference. D.B. Marshall, M.G. Hunter, and A.L. Contreras, Eds. Oregon State University Press, Corvallis, OR.
Today I opted to ignore the looming glacier of bird projects, bills to pay, and New Yorker magazines that I've yet to crack, and instead joined Diane Pettey for trip east of the crest of the Cascades into central Oregon. Diane was interested in trying to track down a Least Flycatcher and a Northern Goshawk family that were frequenting the same area near the town of Sisters (we'll refrain from providing exact locations for raptor nests). She was hopeful of getting pictures of both species as she moves ever closer to reaching her goal of photographing 500 species of birds in the U.S.
We met at my house at 5AM and headed east, bopping along to vintage Tom Petty tunes and chatting about a variety of topics as we made the 100+ mile drive over Santiam Pass. We took a semi-quick detour into Sisters for some snacks and caffeinated beverages. It was the weekend of the annual quilting show and the quilters were out in force. I'd never heard of this event, but Diane forewarned me that Sisters would be a zoo. "At 7AM on a Saturday?" I asked. "Yep" The main street--U.S. Hwy 20--was blocked off at both ends of town and every third vehicle seemed to be county sheriff's deputy, so after parking a few blocks away, we made our way towards the venerable Sisters Bakery.
As soon as we turned the corner onto the main drag, it was apparent that the line at the bakery stretched out the door and several bodies down the sidewalk. In under 30 seconds we decided that we were more interested in birding than the various pastries at the bakery, so we headed back to the car. Thankfully, we happened upon the Sisters Harvest Basket about halfway back to the car. Located at 110 Spruce St., this small health food store has a nice assortment of healthy beverages, fresh-brewed coffee (critical), and a basket of granola bars and other goodies at the front counter. I refilled my travel mug, grabbed a blueberry smoothie and a Tazo Brambleberry, and selected what was advertised as "the best granola bar ever" from the basket by the cash register. I have to admit, it was pretty darn good, full of various grains, nuts, seeds, dried fruits, and honey. Diane chose a gluten-free brownie to go along with a similar array of beverages. She gave me a taste, and it was infinitely better than many "full-featured" brownies I've had. Now that you're hungry, it's time to go birding.
As chronicled in "Nest-o-rama: Woodpecker Wonderland Festival 2009," published in this journal on 12 June 2009, summer is always a great time to visit the varied conifer forests in Oregon's central Cascades. Today we returned to many of the sites that I had visited during the first weekend in June. Nests that were then under construction or full of nestlings are now quiet, as the majority of this season's hatchlings have fledged and are beginning to find their way in the world. Most of these hatch-year birds are still highly dependent on their parents, thus the forest is currently alive with the sounds of begging juvies.
Getting photos of a Northern Goshawk topped our list of priorities, so me made that our first stop. Within seconds of stepping out of the car we could heard the strident cries of a young raptor about a hundred yards or so into the woods. We hastily gathered up our bins and cameras and headed off in the direction of the calls. We readily located two fully-feathered juvenile goshawks perched in plain view about 40 feet up in a dead ponderosa pine. There was no parent around, but we kept our heads on a swivel since adult Northern Goshawks are notoriously aggressive. These youngsters seemed to have little concern about us and they spent most of their energy stretching their legs and wings and persistently screaming for breakfast. We took several pictures and headed off to look for the Least Flycatcher.
We never did find the flycatcher, but during our search we encountered juvenile birds of several species. One of the challenges of birding this time of year is that many of the juveniles look decidedly different than their parents. New birders are often confounded by the first juvenile Dark-eyed "Oregon" Junco they see. They are mostly brown, have no black or gray on the head, and have richly streaked underparts and backs. They look more like a Vesper Sparrow than a junco. Some juveniles put their parents to shame when it comes to appearance. One such bird is the Townsend's Solitaire. Adults sport a uniformly medium gray plumage that is marginally enhanced by two buffy patches, white outer tail feathers, and a conspicuous eye ring. Conversely, a juvenile solitaire is among the most beautifully patterned birds you will ever see (see below).
Though some juvenile birds look dramatically different than adults of the same species, most look like duller and sometimes fluffier versions of their parents. During their initial days and weeks out of the nest, young birds are typically found in close proximity to their parents, which helps in the identification process. In the case of songbirds, juveniles tend to sit still and call persistently until the adult returns. On the other hand, adults that are feeding young will be frenetic as they move about in search of food for their offspring. Young songbirds often sit with their heads tilted back, beak agape, and quiver their wings when the food-carrying adult comes into sight. The squeaky wheel gets the grease. Juvenile birds also tend to be much more confiding and approachable and, as evidenced by this piece, a lot easier to photograph. You may occasionally hear veteran birders refer to such birds as "dumb juvies." Apparently, fear of humans is learned and not innate.
Many of the juveniles we saw today bore no resemblance to their apparent parents. They were Brown-headed Cowbirds. Juvenile Brown-headed Cowbirds are often close to double the size of the adult birds that are observed feeding them. Cowbirds evolved to follow the massive herds of native grazing animals (bison, pronghorn etc.) that once roamed the North American continent. Since they were always on the move, they did not build their own nest. Instead, they laid their eggs in the nests of other, generally smaller, birds. Once hatched, young cowbirds quickly out-grow the young of the host species, which gives them a competitive advantage when it comes to getting fed. In many cases, by the time the nestlings fledge, only the young cowbirds have survived.
With white settlement came the cutting and fragmentation of the continent's formerly contiguous forests, which historically were not inhabited by cowbirds. Cowbirds had been restricted to short grass prairie habitats, but they quickly infiltrated the newly-created edge habitats and agricultural lands, and now pose a serious threat to several woodland species. Today, without any particular effort, we found no fewer than five different species of adult birds either feeding or being followed about by juvenile Brown-headed Cowbirds. These included: Yellow Warbler (a common host species), Warbling Vire0 (another common host species), Cassin's Vireo, Dusky Flycatcher, and Dark-eyed Junco. We observed two separate pairs of adult juncos feeding young cowbirds. One pair was attending to two cowbirds and none of its own young, while the other was feeding one cowbird and one young junco.
As the title of this piece suggests, today was about juvenile birds. The species discussed above are but a small sampling of the young birds we observed on this day. There is no time of the year when there are more total birds living in the Northern Hemisphere. Many will not survive their first migration. Many more will fall prey to predators on their wintering grounds, or in the case of waterfowl and upland game birds, be taken by hunters. As mentioned above, young birds are approachable and in many ways endearing. Now is the time to get out and enjoy the bounty of the breeding season.
All photos taken by Dave Irons
Seven words ... that’s all it took.
The songs of a Bewick’s Wren filled my ears and images of the White-headed Woodpecker and Lawrence’s Goldfinch, seen earlier in the day, were still fresh in my mind as I sat in a hotel room in Kernville, California during the autumn of 1999, celebrating the recent release of my second and third books. And yet, my mind was already jumping ahead in search of a topic for the next book.
This was my second visit to Kernville--the first coming in April 1997. During that visit, local birders had reacted to me in the same way birders do wherever I travel. “I’ve never met a black birdwatcher before.” This seven-word reaction is often among the first words I hear when I meet other birders for the first time.
Having spent the first 25 years of my career working for the federal government, I had an opportunity to visit some of the most scenic areas of the United States. I lived a biologist’s dream life, working at National Wildlife Refuges and National Forests across the country.
Those seven words followed me wherever I went. I’m not sure what caused me to think of those words while sitting in that Kernville, CA, hotel room. But as I began to ponder those words, I began to ask the question... “Why?” Not too long after that, I realized that many other people and organizations were starting to ask the same question: “Why?” As in, why don’t we see more minorities visiting National Parks and National Wildlife Refuges, going birdwatching, or simply enjoying nature?
Soon thereafter, and with encouragement from Kenn Kaufman, Ted Eubanks, and Paul Baicich, I began work on a research project that would ultimately become my latest book, Birding for Everyone. The purpose of Birding for Everyone is to encourage minorities to develop an interest in nature, albeit through bird watching.
Since releasing the book in April 2008, I’ve spent the last 15 months touring the country and introducing the study of birds and the enjoyment of nature to children. I am living the actual vision that came to me in Kernville in the fall of 1999. Cleveland, Ohio; Boston, Massachusetts; San Francisco, CA; Pittsburgh, PA; Atlanta, GA; Columbus, OH; San Antonio, TX; Ithaca, NY; and the list continues. Despite meeting hundreds of young children during this tour, the feeling never changes: each time I have an opportunity to talk to just one young boy or girl and tell him or her about nature and birds, I know that the end result of that encounter may last a lifetime for that child.
I know this from personal experience. You see, when I was in the sixth grade, I did not read books (except whenever the library teacher gave me a book report assignment). That same teacher noticed my apparent dislike for reading and asked why I did not read any of the thousands of books that were in the school library. When I told her none of the books interested me, she simply replied with another question: “Okay, so what does interest you?”
When I told her that I enjoyed chasing the butterflies and looking for crayfish and spiders in my back yard, I saw a smile come over her face ... the kind of smile adults give a child when they know they’ve figured out exactly what the child wants. She went over to the book shelf, retrieved a book, and handed it to me. It was Jack London’s Call of the Wild. I began reading it and immediately discovered that it painted a picture of a world that I never knew existed but, strangely enough, had always been searching for.
Reading that book caused me to create a vision of what I wanted to be as an adult: a biologist. I envisioned myself living in Alaska and studying wolves. Once formed, I carried that vision everywhere I went. It was as strong as ever when I began to prepare my college applications at the beginning of my senior year in high school.
The Travel Begins
Two life-changing events occurred before I was 20 years old. The first was the grade school library teacher who taught me how fun it was to read, thereby introducing an inner city youth to nature. The second occurred during my sophomore year of college, when my school advisor told me I had to take a course called Ornithology.
When I began learning about birds, I found my thirst for knowledge knew no limits. The more I studied birds, the more I discovered about this Earth we live on. For most people, the arrival of spring is merely a date on a calendar. However, for birders, the arrival of spring is marked by the appearance of their first American Robin or Louisiana Waterthrush.
I left Pittsburgh, Pennsylvania traveling west to Ames, Iowa to attend college at Iowa State University. By a stroke of good fortune, I got the opportunity to work for the U.S. Fish and Wildlife Service and the Minnesota Department of Natural Resources at the end of my sophomore year. Upon graduation, I accepted full employment with the U.S. Fish and Wildlife Service and began a journey that would involve me criss-crossing the country as my career began to flourish.
Mound City, MO; Bemidji, MN; Carbondale, IL; Dover, TN; Hayward, WI; Vermilion, Alberta (Canada); and San Francisco, CA. Each new location brought a new job, new life experiences, and a whole new list of birds. The Bachman’s Sparrow in Kentucky; the Northern Gannet in Illinois; the Snowy Owl in Tennessee; the Fork-tailed Flycatcher in California; the Sprague’s Pipit in Canada. At each new location I would hear those seven words: “I’ve never met ...”
The Travel Continues
Upon leaving the federal government after a 26-year career, I spent several years running a global travel business. During that time, I led birdwatching and natural history tours to exotic lands in foreign countries, including such places as Costa Rica, Mexico, and South Africa. In addition to these beautiful destinations, I led tours in the United States (e.g., northwest Tennessee, southeast Arizona, the Upper Texas Coast, and coastal California).
While riding in a safari vehicle in South Africa, my clients and I drew alongside of two wild animals in the Kruger National Park. I vividly recall feeling as though I needed to pinch myself to ensure I was not dreaming. I realized then that my reading of Jack London’s Call of the Wild had led me to this time and place: here I was, just four feet away from two male African lions! The next 15 minutes were spent observing these lions at this incredibly close distance, creating an experience that will forever be etched into my memory.
Less than two years after that once-in-a-lifetime experience in Kruger National Park, I published my book, Birding for Everyone. Many people ask me why I wrote the book. That answer is quite simple: you see, our nation’s population is becoming more ethnically diverse and in less than a generation we will find that various minority populations will collectively make up the majority of the people living in this country. Yet, we know that minorities are disproportionately under-represented among people who are birding, visiting National Parks, or simply enjoying nature. Those beautiful places that you and I take for granted – be they Yellowstone National Park or the Florida Everglades – may not be available for our grandchildren to enjoy if the majority of the voting public does not express a strong interest in nature. It is my vision that Birding for Everyone will be the catalyst to encourage many youth and young adults of this and future generations to begin a study of nature through birds.
In April 2008, Birding for Everyone was delivered to my office from the publishers – the culmination of the most significant creative process I had engaged in during my lifetime. Within days, my phone began to ring. Individuals and organizations wanted me to come speak to their group. And I began to travel.
The message is simple: Nature is here, and it is for everyone to enjoy. Just as one book changed my life and allowed me to travel the world as a result; it is my hope that my book, Birding for Everyone, will change the lives of many thousands, if not millions, of readers.
As I write this, I see that my last two weeks have been an adventurous period in my life: I was in Boston to film a TV show for children; then I spent two days in Pittsburgh to film a segment with five young birders for OnQ Magazine; and now I am on a plane headed for California where I will meet more young birders.
My future plans are just as exciting. By the fall of 2009, I will have created a non-profit organization – the International Institute for Bird Watching. This organization will function to fulfill my purpose, which is to share my ever-expanding awareness and enthusiasm for nature, the world’s natural wonders, and the persistence of vision with audiences that resonate with (or benefit from) those experiences.
I see many more journeys coming up. Care to join me? I hope that you can.
[John C. Robinson is an award-winning ornithologist and wildlife biologist who has introduced thousands of people all over the world to the joys of bird watching for over 30 years. His latest book, Birding for Everyone, encourages minorities and inner city youth and young adults to become bird watchers. Visit www.onmymountain.com for more information. You may also hear John C. Robinson speak at two very important conferences in September: Breaking the Color Barrier in the Great American Outdoors (23-26 September 2009 in Atlanta, GA) and Diversity in Outdoor Recreation: The Many Faces of Conservation in Toledo, OH on 26 September]
I was birding “El Tanque,” just outside of La Paz, Baja California Sur, Mexico. The afternoon was glorious. The warm tropical sun upon my skin combined with a gentle cooling breeze for the perfect temperature; better yet, I was surrounded by throngs of shorebirds and waterfowl. The weather, amplified by the accumulated fatigue of several days of hard birding, sent me into a nirvana-like trance. I simply stood at the water’s edge, an accidental smile upon my face, gazing absent-mindedly at the avian abundance before me. My mind was still rather unfocused when a group of Magnificent Frigatebirds drifted in off the bay, readying themselves for a drink and a bath (see Bathing with Frigatebirds in the April 2009 BirdFellow archive). The photographer within me finally stirred, re-engaging my brain.
As I positioned myself to capture this frigatebird spectacle “on film,” I noticed that one bird, an adult male, was substantially smaller than the others. I also remembered that identifying adult male frigatebirds could be exceptionally difficult, and worse yet, I had no recollection of the distinguishing marks. I had to choose: take careful notes or bet that I could obtain adequate photos. I picked the latter. Fortunately, the bird cooperated. The one feature I did note carefully before hoisting my camera up was size: its wingspan was 2/3 to 3/4 that of the female Magnificents soaring with it and clearly less than that of the male Magnificent Frigatebirds in the vicinity.
After returning to the comfort of my hotel room, I was quickly ruled out Lesser Frigatebird, which always has white stripes on the axilla (the avian equivalent of armpits, where the underwing coverts meet the body). Male Christmas Island Frigatebirds have an oval white belly patch, thus eliminating that species as a contender (James 2004). The remaining three frigatebird species (Magnificent, Great, and Ascension) are completely glossy black plumage. Magnificent Frigatebird is the de facto identification of any frigatebird in southernmost Baja California, where they are fairly common year-round. However, this bird seemed too small to be of that species. Great Frigatebird is a far less likely species, but far from impossible, as it nests on the Islas Revillagigedos off western Mexico and has been recorded once in Baja California (near La Paz, 19 July 2007, Erickson et al. 2008) and twice in California (Hamilton et al. 2007). This species could occur more frequently in southern Baja, lost amidst the swarms of Magnificents. Notably, Great Frigatebirds average smaller in size than the Magnificent, with the wingspan of adult females Magnificent Frigatebirds averaging about 17% greater than that of male Greats. Adult male Ascension Frigatebirds are, essentially, inseparable from Magnificent Frigatebirds, but this species would seem highly improbable in Baja California: it breeds only near Ascension Island off the west coast of Africa in the South Atlantic, with an estimated population of only 20,000 (BirdLife International Factsheet: Ascension Frigatebird).
Identification of the Midget Frigate: Discussion
The size disparity certainly seemed to suggest that the Midget Frigate might be a Great Frigatebird. However, identification of a super rarity should not be based on one mark alone. So, the question arose, “How else does one distinguish an adult male Great Frigatebird from a Magnificent?” When I returned to the United States, I sent photos of the bird in question to Doug Pratt, Peter Pyle, and David James, all of whom were kind enough to provide thoughtful responses. Each person focused on different marks, but in the end (somewhat to my chagrin), all of the marks are mentioned in Howell (1994). This reminded me that a good friend looks at the literature before they pester their buddies…
Howell (1994) and the three gentlemen mentioned above provided the following marks for separating male Great and Magnificent Frigatebirds:
Body Gloss: The body plumage of Magnificents has a purple gloss vs. green in Great Frigatebird. As with gloss in other species, the apparent color can change with lighting and should be used with caution.
Alar Bar: Great Frigatebirds have a paler/brownish alar bar (that is, a bar on the wing’s upper surface that extends from the bend of the wing towards the body) and male Magnificents don’t. Howell (1994) is clear that he believes that this mark is completely reliable, though he does mention that other authors suggest some variability in both species.
Leg Color. Male Magnificent Frigatebirds should have dark legs, while Great Frigatebirds should have legs that are pink to red.
Axillary Barring: Some gray to brownish barring in axillars visible on close view in Great Frigatebird, absent in all or most full adult male Magnificent.
Identification of the Midget Frigate: Conclusion
Sometimes size does not matter. The apparent diminutive size of the Midget Frigate should preclude its identification as a Magnificent Frigatebird. However, its other characteristics all point to it being a Magnificent Frigatebird: no contrasting alar bars, purple gloss to the plumage, black or blackish feet, and no markings in the axilla. This exemplifies the danger of using a single characteristic for identification.
EPILOGUE: Runt Birds
The question does arise, “How common are “runt” or “dwarf” birds?” The problem with that question is that there seems to be no ornithological definition for either term pertaining to adult birds. One could choose a statistical definition, such as 3 standard deviations below the mean size for a given species (meaning the smallest 0.5%), but that definition also has potential for confusion, as size often varies with population and sex. Even if one were to define runt as being the smallest 0.5% within a population, those smallest individuals might be close enough to the norm as to not be obvious in the field.
Many active birders doubt that truly runty birds exist -- in other words, birds small enough to elicit surprise (or misidentification). Certainly, in birds such as warblers, such individuals would be difficult to detect. Exceptionally small individuals would be more apparent among flocks of gulls and waterfowl. I have seen a rare adult Great Basin Canada Geese (subspecies, moffitti) that is distinctly smaller than its cohorts. In geese, it has been established that poorly fed chicks lead to undersized adults (Larrson and Forslund 1991, Aubin et al. 1993, Leafloor et al. 1998). For instance, Canada Geese breeding on Akimiski Island in James Bay average about 8% smaller (using skull length) than geese breeding on the nearby mainland. Leafloor et al. (1998) raised chicks from both the island and mainland on the same diet and, upon reaching adulthood, chicks from both populations were similarly sized. Furthermore, their size approximated that of wild mainland Canadas. It certainly is conceivable that a small female from Akimiski might, on the wintering grounds, appear to be a runt when compared with its comrades, possibly leading to misidentification.
Here in northwestern Washington, the ratty summering California Gull collection seems to show considerable variation in size. On more than one occasion, I have paused to make sure larger individuals were not Herring Gulls. Once, I saw a bird that appeared so small, I initially presumed it a Mew Gull. Some of this variation may be due to subspecific differences, but I am not sure that explains all the variation I see (or at least think I do). However, without catching or collecting these gulls, it is hard to know how much of the apparent size difference is, indeed, apparent (for instance, caused by posture or extreme feather wear) and not real.
I was able to find almost no documented reports of birds that one might intuitively consider a “runt.” A quick search of the Searchable Ornitholgical Research Archive (http://elibrary.unm.edu/sora/search.php) revealed only one instance: An extremely small adult American Crow among 20 collected in New Jersey; though measurements of the bird in question were provided, no comparison to measurements of the other crows was provided (Kohler 1913).
Final Question: Was this really a runt? As I was discussing wingspan, wing chord, and runtism (runtistics?) with Peter Pyle, he queried, “Could your frigatebird have been a vagrant Magnificent from another, smaller, population?” Great Frigatebirds are known to significantly vary in size from population to population (James 2004, Pyle 2008), but to date the amount of variation in Magnificent Frigatebirds seems unclear (Diamond and Schreiber 2002); so perhaps there is another chapter in this story waiting to be told.
I owe many thanks to Peter Pyle for his incredible willingness to answer my questions, some of which were clever and some of which were stupid. Also, thanks to David James, Doug Pratt, and Dick Erickson for sharing their knowledge and providing stimulating discussions.
Aubin, A. E., A. Dzubin, E. H. Dunn, and C. D. MacInnes. 1993. Effects of summer feeding area on gosling growth in Snow Geese. Ornis Scandinavica 24: 255-260.
BirdLife International Factsheet: Ascension Frigatebird. http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=3844&m=0
Diamond, Antony W. and Elizabeth A. Schreiber. 2002. Magnificent Frigatebird (Fregata magnificens), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology.
Erickson, R. A., S. G. Mlodinow, R. Carmona, G. Ruiz-Campos. 2008. The Nesting Season: Baja California Peninsula. North American Birds 61:644-0646.
Howell, S. N. G. 1994. Magnificent and Great Frigatebirds in the eastern Pacific: A new look at an old problem. Birding 1994:400-415.
James, D. J. 2004. Identification of Christmas Island, Great and Lesser Frigatebirds. Birding ASIA 1:22-38.
Hamilton, R. A., M. A. Patten, and R. A. Erickson, eds. 2007. Rare Birds of California. Western Field Ornithologists, Camarillo, California.
Kohler, L. S. 1913. A runt crow (Corvus brachyrhynchos) at Pompton Lakes, N.J. Wilson Bulletin 83:97-98.
Leaﬂoor, J. O., C. D. Ankeny, and D. H. Rusch. 1998. Environmental effects on body size of Canada Geese. Auk 115: 26-33.
Larsson, K., and P. Forslund. 1991. Environmentally induced morphological variation in the Barnacle Goose (Branta leucopsis). Evolution 45: 235-244.
Pyle, P. 2008. Identification Guide to North American Birds, part II. Slate Creek Press, Point Reyes Station, California.
All photos taken by Steven Mlodinow