Fourteen secrets of a Portuguese bird guide

IMG_7240 IMG_7241 DSC03499 DSC03456 DSC03429 DSC03424 IMG_7205 IMG_7233 IMG_7295 IMG_7292 IMG_7248 IMG_7253 IMG_7219 IMG_7223 There are many reasons to bird Portugal. We were lucky to have Bernardo Barreto as our guide. As always with birds, we learned more about life than just about birds.

  1. Look under every bridge, into every thicket, and at every rock pile.
    1. The black-headed weaver shyly nests in a small colony just over the rice field irrigation ditch nearly covered with vegetation, but visible from the bridge.
    2. Across the cork forest by the pond we saw a European kingfisher glint past.
    3. Two little owls peered out of a collapsed stone shed, just visible.
  1. A bird that was there last visit is likely to have remained.
    1. The collared pratincoles were still feeding their babies in the dry field.
    2. The red-rumped swallow babies had fledged but were still flying about the tiled home.
  2. Consider the tide, the light, and the wind.
    1. When the tide went out we saw the blue-winged stilts, lesser black backed gulls, black-headed gulls, purple herons, greater flamingoes, European spoonbills, redshanks, black-tailed godwits, dunlins, curlew sandpipers, Kentish plovers, and green sandpipers in the mud flats.
    2. With the clear light of early morning we saw a golden eagle soaring.
  3. Check every bird in a flock.
    1. First we saw only pallid swifts in the morning light over an old breached dam on the Gaudiana, but then we saw a few rare white-rumped swifts.
    2. Lesser black-backed gulls were less common on the marsh than were the black headed gulls. A careful scanning revealed a curlew sandpiper, and a green sandpiper.
  4. Remain at each place at least half an hour for the shy birds to be revealed.
    1. We had nearly given up at the spot where a rufous bush robin had been sighted above a pond when out he came, singing, hopping, and spreading his long, patterned erect tail.
  5. Eat an excellent lunch.
    1. If possible lunch at Cecília’s, in tiny Alcaria Ruiva, on pork and clams, garbanzos and hare, grilled black pig, or sardines, with home grown tomatoes, Alentejan wine, espresso, and aguardiete, at least for your clients, and hope Cecília will also sing for you.
  6. Never guess the identity of a bird.
    1. Not all birds can be known. Some are too young, too similar, too hidden, or too far away.
  7. Don’t stop pointing out new individuals of species you have already seen.
    1. It is hard to understand a bird at first sighting. Only after seeing many do their posture, their habitat, their flight pattern, and their sociality become clear so later they can be identified at a glance. We saw buzzards, woodchat shrikes, European bee eaters, rollers, red-legged partridges, house martins, carrion crows, little egrets, cattle egrets, and many other birds over and over, finally getting them down easily.
  8. Describe the behavior, ecology, migration, and invasion status of each bird.
    1. The common waxbills are numerous and noisy, invasive from Africa as are the less common yellow-crowned bishop, or black-headed weaver.
    2. We saw few endemics, perhaps the Iberian gray shrike, probably no surprise for the dry, rolling Alentejan plains, or the estuaries.
    3. Many species flock together and some are social nesters like the lesser kestrels and the European bee eaters.
  9. Look at that griffin vulture roost from many different angles on different days.
    1. We never did see a griffin vulture, but it wasn’t for lack of trying. We saw the guano stained cliffs from far to the west, from far to the east, and from far to the north. We spent many minutes staring at the skies around the roost. We heard the story of the dead sheep with many griffin vultures kept back until another more dominant species numbering only two had their fill.
  10. Never count on seeing a bird later if it might be seen here.
    1. We sneaked, engine off, car doors left open, up to see the first European bee eaters at their colony, finally spying three, though deeper into the Alentejo they were common and we probably saw over a hundered.
    2. With our binoculars we followed the first Montague’s harriers across the marsh, but later saw many.
  11. Point out conservation efforts and actions.
    1. There are platforms for the storks on the electric towers and spinning balls where they should not venture.
    2. The electric wires have tassels or colorful wire loops at intervals so birds don’t crash into them.
    3. City hall in Mértola has boxes for nesting lesser kestrels.
    4. Some of the salt pans are maintained just for the birds.
    5. Three enormous private farms are joined to conserve the great bustard.
  12. Appreciate the rare surprises. They are always likely to involve behavior.
    1. At the edge of the marsh a booted eagle pounced on a rabbit, sitting on it for minutes before soaring off with its furry prey.
  13. Look for the rare feature, water in the plains, solid ground in the water, sun in the forest, shade on the prairie.
    1. We stopped at a drying depression before reaching Mértola with maybe a thousand cattle egrets, a hundred little egrets, 50 carrion crows, 10 spoonbills, a coot, 3 little grebes, a stork, 30 black-winged stilts, 2 common sandpipers, 1 green sandpiper, 5 little ringed plovers, a gray heron and 5 house martins flying around.
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Birding from Lisbon, Portugal

Bernardo Barreto picked us up in his dark Ford at 7:30 from the Hotel Berna. We drove northeast out of Lisbon, crossing the Tagus on what might be called the third bridge, upstream from the 25 April bridge, half closed for a film shoot. The Saturday was cloudy and cool, but we knew it would not rain.

The first bird Bernardo identified for us was a zitting cisticola, a warbler with a wren-like tail at an angle to its body as it flitted in the dead reeds of the estuary. Its little body was vertically striped brown on tawny in a beautiful way just between the delicate wing shoulders. Would we ever have figured it out without Bernardo? Perhaps we would have because we had lots of chances to see it skitter and to hear it zitting.

Lisbon tourists take the yellow boat tour. They see the castle on the hill and wander the Alfama. They make take in some melancholy Fado, reminiscent of US country music. They eat grilled sardines or a soupy seafood rice dish. They go to the Calouste Gulbenkian and stare back at Rembrandt, or wonder what that Lalique dragonfly would look like in their hair. They squeeze into those open air taxis to see the sights before heading up to cool Sintra or down to the Algarve and its English beaches. But how many take the time to find a local birdwatcher willing to show them Portugal and its birds? How many spend the night across the river in Alcochete and eat eel or black boar and frothy green wine from a tap in Victor’s, a place so local they try to insist they are full, ineffectually denying our insisted upon reservation?IMG_7188

We saw several exotic birds well established here, common waxbills in post breeding flocks, a glorious yellow-crowned bishop weaver and a pair of black-headed weavers shyly nesting in a small colony of woven ball nests tucked down in the vegetation of an irrigation canal. I try to think fairly of the exotics, for after all, isn’t that what we are, pushing all across the globe and breeding like starlings, now with noisy flocks of teenagers? But of course Portugal is a place our species has been a lot longer than St. Louis is. It also has those hot dry summers that Jared Diamond says favored the growing of heavy seed crops and civilization. It felt good to be in this part of the cradle of humanity and witnessing the climate that let us store and thrive.

I could keep this to being a story of only exotics and ponder the noisy abundance of the waxbills in contrast to the sparseness of the weavers. I could relive those moments when I first saw the bright yellow male cautiously dropping deeper in the gloom as the dull female stood forward, yet both meters down from their precious green ball of young, hanging over the water, visible not to the cars driving past, but only to the birder stopping to check for just such a small colony. Don’t worry, still birds, we’ll leave now. You will be undiscovered until Bernardo or João brings another carload of eager birders.

But there were other birds not yet returned to African wintering grounds, or already back from northern breeding grounds and these were well worth seeing. As always, it is behavior, even the snippets one sees on a driving birding trip, that attracts me most. Feeding, nesting, and hanging out with mates are the commonest acts one sees and this trip was no different. Less compelling is the bird sitting there looking at you as you look at him, desperately matching eye circle or wingbar to the drawing in the book.

The white storks had huge stick nests on platforms high up the electrical lines sparking power into Lisbon. These towers had platforms for storks, as many as five of them, and slow spinning groups of three small spheres to keep them away from the dangerous areas of current.

The collared pratincoles were motionless on clumps of newly plowed field, but their less cautious and uncollared babies screeched for food anyway. They tied with the lapwing perhaps for most elegant bird.IMG_7197

As we finally left the northern estuary for the cork tree meadows, sighting a booted eagle stopped us, rabbit in talons. She sat on the bare mudpan, attracting flybys from carrion crows before soaring high with her soft prey.

Drink more cork  IMG_7202  ! These trees are harvested only every 9 years, by hand as the outer layer is peeled to the russet cambium and a number is painted on indicating the year of harvest. Only the bottom 4 meters or so of trunk is cut, making the trees look like they have entered on some sort of tree diet that involves carrot consumption. Older trees nearing harvest with numbers like 8 from 2008 are black barked, the thick cork cracking and fissuring in places. We passed a cork factory and an outlet mall, but nowhere to buy a cork trivet as a souvenir.IMG_7214

The penultimate sight of the day was a colony of bee eaters, brilliantly colored, improbably level flights. We could only see abandoned holes in the sandbank. Apparently the active ones were on the cliff on our side, which we did not approach. Nor did we approach the lone hoopoe, apparently on assignment for bird watchers, complete with a languid crest lifting.

The day ended where some of the best birding for us began, on mud flats, tide out, could be Bolivar flats in Texas with the spoonbills, herons, godwits, mallards, and coots. But the species were largely different, and the little fishing boats contrasted with the Galveston cargo boats.IMG_7223

You know I won’t tell you how many species of birds we saw. I have to wonder why you even want to know. You are not asking how many families of birds I saw, or even what the total count of individuals was, just what that great year, big day, birding challenge number was. What I will tell you is that birding, feeling the wind, watching the tide, seeing the estivating snails was the best day in Portugal yet.

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Mexican-Ecuadoran secrets of the tufted jay, Cyanocorax dickeyi

Don’t you wonder why birds are where they are? Have you been on one of those guided birding trips where you hop in and out of the van spending ten minutes here, or five minutes there, to see the most birds you can in a precious, expensive day? It can seem like birds are like plants and occur in exactly the same place from one visit to the next. Your guide knows just what those patterns are, just the way you know what birds come to your feeder. But why are the birds where they are?

Some birds are native, where we think they evolved. How do we know this? Well, lots of reasons, but one of the most compelling is that in the tree of life that covers that species, there are related species close by, perhaps on the other side of a mountain or other barrier, or in slightly different habitats. But what about a bird whose nearest relative is over a thousand kilometers away? How did it get there? This is the mystery of the tufted jay.

chara-pinta-tufted-jay-3If you are lucky enough to find a nest, or a nice acorn crop, the noisy, social tufted jays are probably hard to miss in their forested habitat, a tiny stretch of Pacific mountains in western Mexico, more specifically the Sierra Madre Occidental between about 1500 and 2100 m elevation where Sinaloa, Durango, and Nayarit join. This is one of those birds where it pays to know the scientific name, Cyanocorax dickeyi, because it has been called the tufted jay, the painted jay, or, in Spanish, chara pinta. But I digress.

If you look at where tufted jays fall in the tree of life and from that infer where they occur, you would choose Ecuador. So what are they doing in western Mexico, in a different habitat from their nearest relatives and so, so far away? Paul Haemig makes a compelling argument that this is a case where humans intervened, carrying the birds from coastal Ecuador all the way to the metal-rich mountains of western Mexico in pre-Columbian times before any European had pulled out a New World life list. After all, birds were important to the first people of our continents. So were feathers. Captured birds were common in cages and in commerce. Why not bring this fabulous jay from Ecuador to Mexico?

The next step in this story is to visit the evidence that pre-Columbian people did travel from coastal Ecuador to this part of western Mexico. These data are in the hands of the anthropologists. Clothing, ceramics, metallurgical techniques, tomb shapes, designs, language and even simulations of ocean currents all point to this linkage, so the birds had a natural, most likely, human mediated path to these remote and initially inhospitable mountains.

But was there enough time for Cyanocorax dickeyi to evolve the differences it has from its likely ancestor, Cyanocorax mystacalis? After all the Mexican bird lives at different altitudes, has different coloring and who knows what different behavioral, physiological and other differences. I think the answer has to be yes, though the details of the story are likely to be fascinating.

All in all, it makes me want to go back to these remote Mexican mountains, a place I have not been since I was a small child. There I could witness the colorful jay, a living reminder of human travels.

Selected references

Anawalt, Patricia Rieff. 1992. Ancient cultural contacts between Ecuador, West Mexico, and the American Southwest: Clothing Similarities. Latin American Antiquity 3:114-129.

Bonaccorso, Elisa et al. 2010. Molecular systematics and evolution of the Cyanocorax jays. Molecular phylogenetics and evolution 54:897 – 909.

Haemig, Paul D. 1979. Secret of the painted jay. Biotropica 11:81-87.

Kittelson, Meredith, and Cameron Ghalambor. 2014. Tufted Jay (Cyanocorax dickeyi), Neotropical Birds Online (T. S. Schulenberg, Editor). Ithaca: Cornell Lab of Ornithology; retrieved from Neotropical Birds Online: http://neotropical.birds.cornell.edu/portal/species/overview?p_p_spp=514956.

Moore, Robert T. 1935. A new jay of the genus Cyanocorax from Sinaloa, Mexico. Auk 52:274-277.

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Scissor-tailed flycatchers at Mount Doom in Missouri

OLYMPUS DIGITAL CAMERAScissor-tailed flycatchers (Tyrannus forficatus) are highly uncommon in Missouri, but there is a pair nesting right by Mount Doom and yesterday we saw them flying in the distance, against the rocky nuclear waste site. The bird guides do not put these lovely Texas Hill Country birds in Missouri, except for with a rare bird dot, but here they were. First one, then the other flew low, then up onto a telephone pole. The birders with this Audubon-sponsored outing told me that they had a nest earlier in a precarious stem, now destroyed. Others online said there was still a nest with eggs which we did not see. I guess this is the advantage of an active community of birders.

I was glad to see these Texas favorites, but prefer to think of them back in Texas, soaring over the natural granite and gneiss around Llano, or over the limestone outcrops around San Antonio. These great flycatchers remind me that every bird is an individual. Every migration path is particular, taken by many, but flown separately. The terrain is a mosaic, with cerulean warblers here, not there, though the habitat looks identical. Pine warblers were in these pines at Busch Interpretive Center last year, but not this year. The collective knowledge of hundreds of St. Louis birders tells us where and when, then shares it on MoBirds for all. Or you can wait for a St. Louis Audubon Society field trip and learn for yourself.

Are you wondering about Mount Doom? IMG_5357   So was I.  Is it the reason for this large and lovely natural area around Weldon Springs, so close to St. Louis?  After all, how bad could it be when there is a high school right in its shadow. Turns out, it is about as bad as it gets, horrible waste, horrible actions on all sides, towns destroyed, and then it was buried. Is this a good solution? Would it be the solution today? What should be done if you have a munitions factory, nuclear waste, and all kinds of problems like that? They got the contaminants out of a quarry, came up with a plan, then executed it. The result is what the birders call Mount Doom and the government calls The Weldon Spring Site. Is it good or bad? Well, life is much too complicated for those terms. I don’t know enough about the whole thing except to know it is finished. We should keep gathering careful data on the people around there and think hard about what waste we generate, for once we have it, there are are no easy answers. I’m reminded on a much smaller scale of the paint factory on the shores of Lake Waban, on the Wellesley College Campus. There the remediation was a complex mix of removal, burial, and isolation.IMG_5349

But what about those flycatchers?  Why do they have such long tails? Do they suffer from edge-of-range effect here?  I found one interesting study by Laura González-Guzmán and David Mehlman, published in Ecology Letters in 2001 (volume 4, pages 444-452). They talk about several interesting points. One is that there are sink and source habitats. A sink habitat is one where young disperse to but then fail to breed, so the place sucks in naive organisms without ever exporting any. Such places are likely to be more common on the edges of ranges where conditions might be marginal. Our Mount Doom location would be a sink if the birds that come there could never successfully breed. I hope that is not the case, but do not know.

Even if they could breed, an edge-of-range habitat might be unsuitable in more subtle ways. One way biologists have of getting at this is to look at how symmetrical the birds are. The argument goes that bilateral organisms like us will be symmetrical if we have developed under good conditions. Symmetry has been argued as a trait important in mate choice, even in humans. If you wonder about it, just take a piece of paper and cover the left then the right half of any person’s face. Generally you will like one half better than the other and some people have more difference between the halves than others.

What does symmetry mean for scissor-tailed flycatchers?  Well, Laura and David found in the literature that young scissor-tailed flycatchers do not return to their natal lands to breed, but once they start breeding somewhere else, around half of them stick with that locations. This means they could tie birds to breeding grounds and ask about their symmetry. They measured museum specimens, so these birds had seen their last breeding season. (People used to kill birds and put them in museums all the time, but that is the topic of another entry.) Only measurements of the tail feathers showed patterns of variation with location in the range, in ways not predicted at first. Their main finding was that males showed greater asymmetry towards the center, not the edge of their range. This implies that higher quality birds, the symmetrical ones, made up more of the edge populations. Of course, in the denser central populations there were plenty of symmetrical and asymmetrical birds.

The authors interpreted this to mean that the weaker, less symmetrical birds stick around in the center of their range, but in those areas are likely to have poorer territories. In a study like this there are a lot of conditional statements. But the bottom line is there is a pattern, so further work could see if the inferences drawn from this pattern are supported.  What it means for our pair or two of scissor-tailed flycatchers on Mount Doom is that they are likely to be symmetrical. I just hope they succeed in nesting sometime and are not a sink, for I love these birds.

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Birding the California coast at Coal Oil Point, Santa Barbara

Walk the same route over and over so you can get to know the common birds for that place IMG_4709    and notice the rarer ones. Here is a walk I took for three weeks while working at the Kavli Institute for Theoretical Physics.IMG_5176

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whimbrel

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Anna’s hummingbird

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black phoebe

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snowy plovers

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willets at low tide.

Out the door onto the mowed grass of West Cottages, UCSB housing, where the California towhees scratched, hopped back, peered down, showing their russet rumps, then repeated. A dull western bluebird perched on the wall, its mate nearby in an oak. White-crowned sparrows stayed closer to the bushes as they foraged in the grass. One caught a cricket and swallowed it, head first, spiny cricket legs sticking out last.
Out on the road, I looked down to the lagoon where the great white egrets and black-crowned night herons lurked. Out in the high tide lagoon were Western grebes, buffleheads, ruddy ducks, and mallards. But I did not turn that way. I turned towards the beach.
I imagined students crafted the signs telling of vernal pools and coastal scrub here at Coal Oil Point biological station. I took the narrow path that hugged the wooden fence keeping us up on the cliff and out of the dunes. A rabbit dashed across the path, improbably small in the scrub. An Anna’s hummingbird male perched squeaking high on an agave stalk. A black phoebe dipped its tail, then flew off its perch and out over the dry meadow.

No researchers occupied the labs of Coal Oil Point early this Sunday morning, but a yellowthroat darted into the lusher bushes along the building. A song sparrow sang a buzzy variant of the song I know so well from Michigan. A surfer parked his bike and walked down the bluff into the waves, already wearing his wetsuit.
I went down the rough path carved into the bluff up to the rising high tide. Pacific and California gulls flew off the point. A group of willets pondered the surf. Three pelicans flew past, a constant reminder that we almost lost them to pesticides. A lone wimbrel walked across the dunes.

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marbled godwits

There were no sanderlings in this high tide. I walked on down the beach towards the outlet of the lagoon. There I saw them, nestled like rocks in the clumpy dunes. Snowy plovers fluffed themselves out as they waited for the tide to recede. I took their photo and turned around, not continuing to the monarch wintering grounds, for the lagoon was filling. The slough was open.

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brown pelicans

My run would have to be on the bluff-top trail, so I went back up, causing 3 California quail to dash across the path. I ran a modest mile, stopping for the view at the point and the high tide waves crashing across the rocks. I had finished listening to Lonesome Dove and had moved on to Streets of Laredo.

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white-tailed kites

On my run’s return, I saw two white-tailed kites perched in a dead snag high over the coastal scrub.
There is no end because there is no beginning, just the tide peaking and withdrawing, the foam blowing and subsiding, the surfers paddling, then riding, and the never-finished shorebird hunt for food in the wet sand.

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2012 in review; much more to come to SlowBirding in 2013!

The WordPress.com stats helper monkeys prepared a 2012 annual report for this blog.

Here’s an excerpt:

600 people reached the top of Mt. Everest in 2012. This blog got about 9,500 views in 2012. If every person who reached the top of Mt. Everest viewed this blog, it would have taken 16 years to get that many views.

Click here to see the complete report.

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Bald eagle swoops in for the kill – and misses

American Bald Eagle fall mating ritual

Image via Wikipedia

Currents of shore birds lifted above the Brazoria National Wildlife marshes on a cold February day. Thousands of sandpipers, dowitchers, yellowlegs, stilts, and ducks fled the hunting bald eagle. A blue-winged teal flew across the marsh, now high, then low, with the eagle in pursuit. This one teal had become the target and was fleeing for its life. It was likely to succeed because it was fighting for its life, while the eagle was simply fighting for its dinner, as Richard Dawkins put it so clearly in The Blind Watchmaker. The other reason the teal was likely to live was that this was a second year eagle, mottled white on its breast. It was clearly still learning when to give up the chase and move on. I wouldn’t exactly say it was toying with this duck, or that one, as it coursed across the marsh, but the eagle didn’t seem to be too serious either.

I looked over at our students, standing on the low dike bordering the marsh. They were cold, for a couple of hoodies were about as much as they could imagine. They huddled in two groups, slightly separated, but tight within the groups, sheltering from the wind. All 11 pairs of binoculars were pointed skyward. Most of them had never seen a wild eagle, let alone one that might catch a duck. I hoped I was witnessing an important event in their lives, one that would be told tonight back in their Rice University colleges, Wiess, Sid, Baker, or Jones, and again in other years, perhaps whenever they visited a marsh, or sat around a campfire.

This is one of the joys of teaching, being there when the spark begins. Eagles hunting ducks cannot be scripted the way the quiz we were about to give can be. I suppose we need the quizzes, for we need to generate a little focus, but I’ll take the hunting eagle any day.

I’ve seen many eagles over the years. I’ve seen them sitting in the trees along the Yampa River near Steamboat Springs. I’ve seen them flying low over Pilant lake at Brazos Bend State Park. Two weeks ago we saw two bald eagles in trees overlooking the Mississippi river, near Alton, on the Illinois side. Last week, in February 2012, three years after the Brazoria eagle, I saw 4 eagles, all second year, from the Missouri River Runner Amtrak train bringing me home to St. Louis from Kansas City, where I had been to give a talk at Avila University. But enough about rivers and their motionless eagles. What is known about hunting eagles?

Bald eagles, scientifically known as Haliaeetus leucocephalus, in the Accipitridae, are meat eaters who are happy with carrion, but also catch their prey. Joseph Buchanan and James Watson (2010) watched bald eagles in Oregon and Washington. They found that eagles could catch their prey on the wing. They also found that eagles could predict exactly where a duck would surface, and swoop down to catch it just in that moment of interface between water and air. They saw western grebes and buffleheads meet their end in this way at Eld Inlet, off Puget sound, in Washington. They also reported a clumsy kind of cooperative free-for-all as mostly immature eagles hunted herring gulls. I can’t imagine gull would be a meat of choice, but they were abundant at the study site. The description is detailed. Here is a piece of it: “At 08:31 the 2 Bald Eagles abruptly discontinued their pursuit of the gull and began to attack another Herring Gull. Two other sub-adult Bald Eagles joined the attack almost immediately. The chase began at 30 to 50 m above water, the height at which most of the gulls were soaring. The eagles made at least 40 approaches of the gull until 08:34 when the gull dropped down to fly within about 10 m of the water, where the eagles made at least 40 more approaches.” The story goes on, ending with the eagles giving up, though other attacks were apparently successful.

Adult gulls flee hunting eagles successfully, but in some places the eagles find gulls that cannot leave so easily. Glaucous-winged gulls nest in groups in Barkley Sound, British Columbia. There, White, Heath, and Gisborne found indirect evidence that they preyed on chicks, and forced the gulls to put more time into vigilance, time taken away from foraging for the chicks. Indirect evidence means they did not see an eagle taking a chick or egg. What they did see was eagles hanging around the colony, something that peaked in late June, with about 4 eagles seen per visit to the 45 gull colony. The gulls were more likely to take flight when eagles were around and more of the gulls were vigilant, looking around, presumably for eagles and other predators. The investigators found that 89% of the gull nests were empty by 6 July 2005, though they could not rule out the impact of a storm. This study is highly suggestive that eagles are bad news for nesting gulls, but it cannot rule out other causes of the gull behavior. The eagles peaked when the chicks were young, so the increased vigilance behavior could be because of the eagles or it could be a correlate of something else. This happens commonly in science, and we must be careful to understand exactly what we know and what we do not know. This study indicates the researchers are onto something that warrants further study, not something completely understood.

Eagles eat a lot of other things, from fish to carrion. They migrate, making it likely their food varies by location. There are a lot of other interesting things they do, at the nest and away. But I’ll leave those for another time. For now, I’ll just remember the Texas eagle chasing a duck and the Missouri eagle high in a tree over the river.

Buchanan, JB & Watson, JW 2010. Group hunting by immature bald eagles directed at gulls. Northwestern Naturalist 91:222-225.
White, AF, Heath, JP, & Gisborne, B. 2006. Seasonal timing of bald eagle attendance and influence on activity budgets of glaucous-winged gulls in Barkley Sound, British Columbia. Waterbirds 29:497-500.

CC 2.0 license, Eric Frommer: Haliaeetus_leucocephalus_-Skagit_valley-8.jpg

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