author and lifelong birder
Here is the story of a species of bird that has flourished on continents where it was introduced during the 19th century while at the same time suffering serious decline in its native Europe. In North America, there were close to 200 million European starlings …
Across North America, there are about 50 native species of shorebirds, not including occasional rare visitors, and in Europe these birds are called “waders” because that is what they do. I first saw waders as a teenager at Spurn Point in the north of England …
One of my favorite species of birds is the surf scoter, a sea duck that is abundant during October through April along the North American west coast as far south as central Baja (Mexico), after breeding in the boreal forests and tundra of Alaska. It also winters on the east coast from Nova Scotia to Florida. While not native to Europe, a few vagrants are blown off course or become disorientated and finish up wintering as far south as the UK. It was one of these vagrants that I witnessed at Spurn Point back in the early 1960s which supposedly was the first surf scoter ever seen there.
Surf scoter Range Map
These large, stocky birds, are 19 to 24 inches (50 to 60 cm) in length and are often are seen in flocks during winter on North American estuaries and marine waters close to shore. They usually are closely packed and may take off as a group if disturbed. Even in summer, the species appears as an occasional summer resident in California and can be seen around river mouths and near harbors. Consequently, what was rare for me in the UK is now commonplace in California.
Flock of surf scoters
However, one of their risks where I live is oil spills. The recent October 2021 Huntington Beach spill in southern California is an example even though the spill was reduced to only 25,000 barrels by the time it was over. Deceased birds in that spill have been identified as the American coot, black-crowned night heron, brown pelican, two species of cormorant, western and California gulls, Northern fulmars, several shearwaters, and a red-footed booby. Fortunately, no surf scoters were reported. Birds that survived their oiling included ruddy duck, snowy plovers, sanderling and western grebes. However, avian casualties are notoriously difficult to calculate. For example, the April to September 2010, 87 day Deepwater Horizon spill, that released over 200 million gallons of oil into the Gulf of Mexico, is estimated to have killed over 100,000 birds, even though only 8,200 carcasses were collected.
Huntington Beach oil spill
When birds become oiled, their outer feathers clump together and are no longer able to repel water which percolates into their inner down feathers, causing hypothermia. The bird may then die of exposure, sink and drown, or if the bird makes it to land, becomes vulnerable to predators because it cannot fly.
Surf scoter impacted by the Cosco Busan oil spill
The November 2007 oil spill in the San Francisco Bay of an estimated 53,000 gallons, caused by the Cosco Busan hitting the San Francisco – Oakland Bridge, created a much greater impact because it occurred where and when there were hundreds of thousands of migrating and wintering birds. 27 species were affected, and an estimated 2500 died, with many more than that likely left to perish elsewhere. The surf scoter was top of the impact list, with an estimated four percent of its wintering population in the Bay Area being lost as a result.
Surf scoters are members of the sea duck family that includes eiders, goldeneye, bufflehead, Harlequins, and mergansers. Their first name comes from their habit of foraging in ocean surf, whereas the origin of the word “scoter” is unknown. Male adult scoters are unmistakable when seen on the water, with velvety black plumage, a conspicuous white forehead and nape, and a large swollen, irregularly-shaped, multi-colored bill (orange-yellow, white and black). The species is sexually dimorphic (exists in two distinct forms), with the female possessing duller brown feathers, slightly darker above than below, and sometimes pale patches of plumage on the cheek and nape. The female’s bill is dark grey.
The surf scoters’ diet includes mollusks, crustaceans, some plant material, small fish, herring spawn and aquatic insects, which are caught by diving and using their specially adapted bill.
Surf scoter breeding
Population numbers are not well understood but generally are believed to be in decline. For example, in 1987, around 30,000 birds were estimated as wintering in the San Francisco Bay, whereas that number has fallen to around 3,000 in recent years. Even so, rough global estimates estimate around 500,000 individual birds, but with numbers falling. Reasons for the decline are unclear but probably includes global warming that is reducing the size of their breeding grounds, increased development in urbanized estuaries, contamination and pollutants affecting reproduction, invasive species affecting the food chain, and individuals falling prey to bald eagles, river otters, orcas, and sea lions.
Even so, they are a delight to watch as they congregate together, bob as black specks on the water, plunge head-first to catch their prey, and fly short distances to improve their foraging success. Sometimes they are not alone.
It should be noted that there are two other types of scoter resident in North America, the black scoter and the white-winged scoter. Both are nearly circumpolar in their distribution north of the Equator, and in Europe there is also the common scoter and velvet scoter. Until 2009 the Eurasian common scoter and the North American black scoter were considered the same species but are now recognized as separate species. Similarly, the Eurasian velvet scoter and the North American white-winged scoter have been considered the same species.
The black scoter adult male is all black and characterized by a bulbous bill that is mostly yellow. The female looks like a female surf scoter, but with more extensive pale areas on its cheeks and neck. The white-winged male is mostly silken black with large white patches on its wings, an orange-red bill, and a white comma-shaped patch around the eyes. The female is dark brown, lighter below, with two smudgy white facial patches and white wing patches.
Additionally, it is not unusual to have other species of duck mixed in with flocks of scoters. Two species of duck that are primarily black and white, and might cause confusion, are the goldeneye and bufflehead. The goldeneye is medium sized, has a much smaller bill that is blackish in color, has an iridescent green head, a white spot behind the bill, and its neck and underparts are white, unlike the dark feathers of the scoter; females have a warm brown head and a yellow spot at the end of their bill.
The male bufflehead is conspicuously white and black, with a white chest and flanks, an iridescent purple-green head and throat, and a large white patch on the back of the head. The female is brownish with a single white patch on the cheek.
Finally, do not confuse scoters with the much smaller American coot that is dark brown, other than for its white bill tipped in black. Also, it prefers fresh-water lakes, ponds and rivers rather than marine water.
American coot
Spurn Point
Hopefully, we will spend more time in the future studying and increasing our knowledge of these spirited sea ducks, and protecting their numbers. Progress has been made with establishing procedures for oil spills. Much has been learned as a result of several major spills: the 1967 Torrey Canyon disaster off the coast of southern England that released 25 to 35 million gallons of crude oil; the Amoco Cadiz incident off the northern French coast in March 1978 that released nearly 60 million gallons, killing an estimated 20,000 birds; the Santa Barbara catastrophe of 1969 that spilled up to 4.2 million gallons of oil; and the Exxon Valdez 1989 incident that leaked about 11 million gallons of crude oil.
In chapter 5 of She Wore a Yellow Dress, I describe my first date back in 1965 with a fellow Hull University undergraduate who became my wife. She curiously asked about my favorite hobby, and when I said it was bird watching, she wanted the …
One of the very few families of birds that remained constant when I moved from England to California in 1979 was the family of terns. I regularly saw Sandwich, Arctic, common, black, and little terns during my visits to Spurn Point in Yorkshire, and during …
This is a memoir of a COVID-invigorated Bird Spotter and his July 2021 journey from Half Moon Bay to the pinnacles of the Southeast Farallon Islands, and waters beyond, in search of pelagic birds: puffins, shearwaters, storm-petrels, and albatross.
My thanks go to Alvaro Jaramillo who organized the trip, the crew of the New Captain Pete who took us on the journey, the bird spotters who saved me the effort of using my bird book, and my daughter for her 2021 Father’s Day gift and willingness to accompany me. During the COVID pandemic, I have revived my childhood hobby of birdwatching, but with over 850 species inhabiting the United States, recognition is a very challenging task. Too often, birds disappear before you have time to identify them, so I am still gathering expertise.
The purpose of the trip was to learn how to recognize new Californian pelagic species and to refresh my memory on those pelagic species I had encountered at Spurn Point in England, during the 1960s. Here was an opportunity to travel with experts.
The journey involved an early morning departure, the sky was overcast, the sea was heaving, there was a chilly wind blowing onshore, we were warned of sea sickness once we left the harbor, and told that we would be on board for 10 hours. I had struggled earlier in the morning to decide how many layers of clothing to bring so that I would remain warm but not hot. The boat’s destination was to be a cluster of inhospitable, rocky peaks, about 35 miles from Half Moon Bay, known as the Southeast Farallon Islands, and afterwards we would visit the edge of the continental shelf, several miles to the west. I wondered what might happen.
The expert bird spotters on board quickly reported shorebirds they had identified, even before I had drunk my coffee and the vessel had passed beyond the fog horn at the entrance to Pillar Point Harbor. During late May, 2021, an experiment was begun using sound baffles to lessen the noise of this fog horn, without jeopardizing marine safety, as the authorities responded to resident complaints that the warning signal, given off every 10 seconds, is too loud. Some people argue the noise keeps them awake at night whereas others claim it lulls them to sleep!! Having used a local hotel the night before, I would vote with the former.
Brown pelicans at half moon bay
If you ever want to see brown pelicans, this is the place to visit. There were hundreds along the harbor walls, roosting, preening themselves, communicating with their neighbors, waiting for food, or simply watching passing traffic. Other species identified by my colleagues included a black oystercatcher, wandering tattler, double-crested cormorants, and on the water, pigeon guillemots, common murres, and a pair of marbled murrulets. The occasional Caspian tern, the largest tern in the world, circled above with its head down, before plunge-diving into the water for its breakfast. This was a fine start to the day.
Caspian tern
The birds that caused the most excitement were the two marbled murrulets, about the size of American robins, because of their rarity. Strangely, although it is a seabird that feeds offshore, as well as making use of inshore bays, it nests among the branches of old growth trees from Alaska, south along the Pacific coast, to the Santa Cruz Mountains. Only a single egg is laid, and because of the human destruction of their nesting habitat and their eggs being eaten by ravens and jays, they are now endangered in California. This was a species I had never seen before, and I quietly celebrated as it was added to my life list.
They were no longer present on our return, but other species spotted in the harbor at that time included a ruddy turnstone, surfbird, willets, and a pair of surf scoters.
Marbled murrulet
During the journey to the islands, we quickly lost sight of the shorebirds, and left behind the pelicans that rarely feed more than five miles from shore. They were replaced by hundreds of sooty shearwaters, common murres, and pigeon guillemots. No one spoke of the many gulls we saw except for a comment about a Heermann’s gull that was accompanying several brown pelicans, presumably intending to steal their food.
Heerman’s gull
By now, cameras were in use to capture the important ornithological moments, binoculars were gazing out to sea, looking for something new, and the most serious guests were meticulously noting down the species they had spotted and the population count for each variety. Personal breakfasts were in progress, except when food was grabbed by the wind and blown overboard; the less brave rested in the wind-protected cabin, but so far no one was sea sick. The greatest commotions occurred when we passed spouting humpback whales and sighted Pacific white-sided dolphins.
As we came close to the Southeast Farallon Islands, more and more birds appeared in flocks as they returned to their nesting locations. New species appeared such as Northern fulmars, pink-footed shearwaters, Cassin’s and rhinoceros auklets, and red-necked phalaropes. I recall seeing the first and last of these species many years ago at Spurn Point. It was easy to miss the auklets because of their small size and their habit of diving quickly as we approached them. They are one of very few species that can “fly” underwater. Others include common murres, puffins (a type of pelagic bird), dippers, penguins and gannets.
Curiously, no one mentioned the many gulls flying around, such as Western and California gulls, possibly because these birds are regularly seen onshore.
Red necked phalarope
Probably the most memorable sight of the day for me was observing the about 20 small, dainty red-necked phalaropes (slightly larger than a house finch) swimming and spinning on the water. These are very special birds, one of the few species that exhibit reverse sexual dimorphism, with the female displaying the more colorful feathers and being the one that selects the mate. Once she has laid her eggs, she may disappear to find another mate, leaving the original partner to incubate the eggs and to take care of the young chicks.
Even before we arrived at the Farallones – where you are not allowed to land – we sighted our first tufted pelagic bird; a puffin, about the size of a pigeon but twice its weight. It was out fishing but detoured to inspect our boat, using its poorly developed wings that require strong and rapid wingbeats to stay airborne – up to 400 beats a minute. It flew directly towards us staying close to the ocean. More puffins appeared once we were among the Southeast Farallon Islands. They are members of the auk family and are found along open waters, islands, and rocky cliffs of the north Pacific. Population estimates are about 2.5 million birds worldwide. This species is larger than other puffins and each bird has a distinctive white “face mask”, with golden head flumes during the breeding season. Once it finishes breeding, it spends up to eight months out at sea and is rarely seen at this time.
Tufted puffin
The islands are amazing. You are greeted by the unforgettable noises, echoing off the cliffs, of thousands of seals and sea lions, and hundreds of thousands of breeding birds, and you cannot miss the foul smell of their guano. I have never seen anything like it. The islands are home to the largest seabird nesting site in the contiguous United States and the largest colony of Western gulls in the world. Half the world’s population of ashy storm-petrels (another class of bird I added to my life list) is resident here, and more than 400 avian species have been recorded. We entered the relatively calm waters near the islands, and stopped to inspect the wildlife.
Ashy storm petrel
The jagged peaks and craggy shores, and the sea that surrounds them, teemed with life. Even some gray whales swam by. In the distance, there were huge congregations of common murres, pigeon guillemots, and Western gulls, and nesting colonies of Brandt’s and double-crested cormorants. The latter two species had segregated themselves, with the double-crested cormorants occupying nests higher up the cliff. Technically cormorants are not “pelagic” (i.e. do not inhabit the open sea), because of their need to stay close to the land to dry their non-waterproof feathers.
The Southeast Farallon Islands are largely barren, and part of a granite ridge running northwestward that appears above the ocean surface to create this inhospitable archipelago. The granite originated in Cretaceous geologic times, about 100 million years ago, deep under the earth’s surface, apparently in the same magma core that formed the southern Sierra Nevada Mountains (such as Yosemite). This block was torn off far to the south, possibly 300 miles away, and because it was attached to the Pacific Plate, the fragment has slowly drifted north. The boundary between the Pacific Plate and the North American Plate is located a few miles to the east of the Farallon Islands, and is marked by the San Andreas Fault. Estimates are that the islands are moving north, on average, by a little over an inch (3 cm) per year.
These almost inaccessible islands, with sheer cliffs, make you want to discover more about their history. Here is what I found out:
Farallon National Wildlife refuge
Farallon house mice
But it is time for me to return to bird watching and the marine life along our journey. Next, we sailed westward over the Continental shelf, and were greeted by a change of bird species. Most prominent was the appearance of several black-footed albatrosses, yet another pelagic bird! These large seabirds, with long, narrow wings, dark plumage, and a long, thick bill, used for feeding on the surface of the water, were as curious about us as we were of them. They settled on the water close to the vessel as we stopped to take photographs. The birds roam the north Pacific, but nest primarily on the Hawaiian Islands.
Black-footed albatross
During this part of the journey, we also encountered a blue whale, the largest animal known to have existed, as it surfaced to breathe while eating. There were also several lone mola mola, or sunfish, that we passed, flapping their bodies while lying on their sides near the water’s surface. These strange-looking fish have a truncated body with large head that is equipped with long dorsal and anal fins.
Thus my outing came to an end. It seemed a lengthy journey back to the harbor, with the same sequence of birds that we had spotted earlier, but in reverse order. As soon as cormorants began to fly close to the boat, and brown pelicans reappeared, I knew we were close to land, even though I could not see it. The cormorants were in convoy, flying low over the water, and the pelicans were out fishing. The temperature had risen, my clothing had turned out to be perfect for the weather, the sea swell had almost disappeared, the wind had dropped, and the sun was fighting its way through the high clouds.
I reflected on my birding achievements. I was now able to distinguish between sooty shearwaters, common murres, and pigeon guillemots, without reference to my bird guide, and a more proficient birder on board confirmed the accuracy of my identification.
Sooty shearwater
All in all, the outing accomplished its purpose of sharpening my knowledge of California’s pelagic birds and reintroducing me to species I had been familiar with in the UK. The next stage, as I return to birdwatching, will be to improve my knowledge of shorebirds, such as sandpipers, plovers, oystercatchers, and avocets. There are many species in North America and these birds are often migratory and forage for food at their California stop-over sites during their long journeys between the Arctic tundra and their non-breeding locations in the southernmost parts of South America. We disembarked, I bid farewell to my daughter, who left for San Luis Obispo, and I set off for Marin County. I was relieved that I had not experienced seasickness and pleased that the COVID pandemic had caused me to return to my childhood hobby of birdwatching.
For thousands of years, domesticated pigeons have been an integral part of human life. Egyptian hieroglyphics and stone carvings in Mesopotamia (now modern Iraq) indicate that these birds were domesticated at least 5,000 years ago. Over centuries they have been kept as symbols of prosperity, …
It was the summer of 1954 when my childhood hobby of birds’ egg collecting came to an end. The British government implemented the Protection of Birds Act, 1954 that forbid me to take wild birds’ eggs, and at the same time, protected adults and their …
During the 1950s and 1960s, as a young birder in the north of England, I ignored the rather common, drab and inconspicuous-looking birds known as house sparrows and tree sparrows. Both are Old World species, distributed across Europe and Asia, and rarely migrate significant distances. The house sparrow forages for grain and seeds and household scraps, whereas the tree sparrow’s diet includes fruits and invertebrates. There was a third kind of “little brown bird” that I could see furtively skulking among the hedgerow, that I called a hedge sparrow. However, later in life, I was told it was not a member of the sparrow family, and I should call it a dunnock.
Eurasian dunnock (not a hedge sparrow!)
The house sparrow appears in my novel She Wore a Yellow Dress, in particular in Chapter 23, titled The Cockney Sparrer. Back then, in 1968, I worked at Ford in Dagenham, and the cockney people who I now worked with were supposed to chirp like sparrows and move around in groups like sparrows; hence their nickname of sparrers.
Unfortunately, it seems that these birds suffered due to their closeness to humans. Today, while the house sparrow population has stabilized, during the 1977 to 2006 period, their numbers declined about 70 percent, and the tree sparrow population fell by 93 percent. Agricultural change, pollution, the wider use of pesticides, more cats, less availability of waste food, and maybe even diseases, caused these reductions.
The Great Sparrow Campaign, China in 1958–1961
Another example of the decline in sparrows happened in China during 1958. The country implemented its Great Sparrow Campaign to cull the tree sparrow population because it was believed the bird was contributing to the declining yield of farmers’ crops. Several million birds were slaughtered. What was not realized was that the tree sparrow eats locusts, and because of the culling of sparrows, these insects multiplied, invaded the fields, ate all the vegetation they could find, and caused an even greater reduction in food supplies. The outcome was the Three Years of Natural Disasters during which tens of millions of Chinese died of starvation.
Once I moved to the United States, there was a dramatic change in the number and varieties of sparrows I could see, although there were still a few Eurasian house sparrows. Th Eurasian species was introduced deliberately into the United States, when eight pairs were released in Brooklyn, New York in the mid-1850s. These birds flourished and rapidly spread across the 48 lower states and parts of Canada. They arrived in California during 1910, and by the 1940s, it was estimated there were about 150 million house sparrows in North America They became regarded as pests because of the food they ate and the displacement of native species that they caused, such as robins, chickadees, and bluebirds. As in Europe, their numbers declined dramatically and the current population is estimated to be around seven million. Even so, the worldwide number of house sparrows is put at close to half-a-billion.
Where have all the sparrows gone?!
The highly active Eurasian tree sparrow also made its way to North America but was less effective in broadening its range. It was brought from Germany, with a dozen or so released in St. Louis during 1870. The species took hold but were restricted geographically because of the more aggressive and adaptable house sparrow.
Now I need to comment on North America’s species of native sparrow that I have come to know since moving to the San Francisco area. They comprise some 35 to 50 species, including several that do not carry the sparrow name, but for now, let me focus on the California varieties. Here we have the white-crowned sparrow (resident along the coast but with migrants inland during winter, and recognized by their distinctive zebra-like black and white head feathers ). Then there is the golden-crowned sparrow (a winter visitor with a golden stripe on its crown, bordered by black). Thirdly, there is the resident rufous-crowned sparrow (with a rufous crown, grey face, grey underparts and rust-colored stripes on its back); there is the song sparrow, the most widespread and most common resident in California, typically seen close to water (and usually singing its heart out from a perch); and then there is the chipping sparrow, a summer resident that migrates mostly to Mexico for winter (crisp and cleanly shaped, frosty-colored underparts, bright rusty crown and black line through the eye). Last but not least is the Eurasian house sparrow that I have already mentioned.
Somewhat rarer are the Lincoln sparrow (winter visitor that looks similar to the song sparrow except it has a buffy-colored appearance); the white-throated sparrow (winter visitor, with a white throat and yellow between the eye and bill); the grasshopper sparrow (summer visitor; brown and tan with slight streaking and a species whose population has tumbled 70 percent during the last 50 years, probably due to habitat loss, pesticides, and brood parasitism); the fox sparrow (winter visitor; rust-brown above and grey on the head); and the savannah sparrow (year round; brown above and white below, yellowish stripe over the eye, and crisp streaking). Occasionally, rarer species turn up such as the LeConte’s sparrow, and with so many species you can be excused from recognizing them all.
Just to add to the confusion, there are several species that are not named “sparrow” but belong to this family. Examples, frequently seen in my backyard, are the black-hooded dark-eyed junco, the all-brown California towhee, and the orange and black spotted towhee. All usually forage on or near the ground, and can be seen kicking up food with their feet.
So where does the word “sparrow” come from and why are North American birds given the name when they are not related to the family of Eurasian sparrows? They belong the “bunting” family, and it is presumed that early immigrants saw “little brown birds”, like the ones back home, and adopted the name “sparrow” because it was familiar to them. The English word “sparrow” is derived from the old Anglo-Saxon word “spearwa”, meaning “fluttering”.
Snow bunting
Just keep things complicated, there are also several species of bunting in Europe. The one I often saw migrating was the snow buntings, and it is one that winters in the United States. Other North America species of bunting include the Lazuli, Lark, Indigo, Painted, and Varied buntings. In the UK, the corn bunting, reed bunting, cirl bunting, Lapland bunting, and yellowhammer (“ammer” means bunting in German) are the family’s representatives.
Inadvertently, we have another Americanism where the American word describes something very different from what it does in the UK. It joins such words as pavement, chips, biscuit, braces, and purse.
Blue-crowned mot mot The first resplendent quetzal I ever saw was on April 5, 1998 in the Monteverde Cloud Forest, Costa Rica. The species is considered by many to represent the most beautiful bird in the world, and although it was partially obscured by …
Growing up in Yorkshire, I called them waterhens (now more usually known as moorhens). They are humble birds, preferring freshwater wetlands, and are sedentary, except that they are joined by birds moving from north-west Europe to winter in the UK. As their name implies, they …
Meet the Eurasian common cuckoo bird and the North American brown-headed cowbird, both brood parasites.
As a boy many years ago in northern England, I pursued a little brown bird called a hedge sparrow, flicking its tail and shuffling through dense bramble undergrowth and along a hawthorn hedge, carefully carrying several furry brown caterpillars in its bill. Today there are about 2.3 million breeding pairs of hedge sparrows in Britain. The dingy-colored bird was about 5 inches/14 centimeters long, and is called by some a “dunnock” because of the Old English meaning of “dun” for brown and “ock” for little.
As the bird disappeared, I pushed inside the thorn-bearing bushes and could see the nest but not reach into its cup-shaped construction because the thorns tore at my skin. Instead of it containing several fledglings, there was only one large barrel-chested chick that was constantly calling for food and already twice the size of the hedge sparrow. I realized that I had discovered a young cuckoo bird under the care of its adopted parents. The common cuckoo, a dove-sized bird, is a migrant to Britain from early April to late July, and winters in Africa south of the Sahara. It enjoys a wide breeding range across Europe and Asia, and while there are concerns for its future in the UK, with an estimated global population of around 50 million, it is not considered threatened globally.
Common Cuckoo Range Map: orange – breeding; green – migration; yellow-wintering
It is one of very few brood parasites among birds that uses other bird species to raise their young by laying eggs in the other birds’ nests, usually birds much smaller than they, such as the dunnock, meadow pipit, robin, pied wagtail and reed warbler. During spring, it is usual to hear in the distance the male’s repeated and monotonous cuck-oo call that it uses to attract its mates for breeding. The adult cuckoo bird has dark blue-grey plumage on its upper parts, and dark barred feathers on a white background below, plus a long, graduated tail and pointed wings. Its general appearance is similar to a small hawk.
Since my sighting, the number of cuckoos in Britain has declined by over three-quarters to around 15,000 breeding pairs. The reason for the decline is unclear and maybe as much to do with the bird’s more perilous migrations each year caused by drought rather than loss of habitat and decline of food resources. Its hosts remain abundant although possibly due to global warming they now nest earlier, thus reducing the number of suitable nests available for the cuckoo to parasitize.
Curiously, the three cuckoo species in North America (yellow-billed, black-billed and mangrove) are not brood parasites – they rarely lay their eggs in the nests of other species – instead building their own nests and rearing their own chicks. They are less noisy than the common cuckoo bird, often emitting a softer cooing sound.
To find a brood parasite in North America, you have to turn to the stocky brown-headed cowbird, the main obligate brood parasite on this Continent. There is also the bronzed or red-eyed cowbird, but its distribution is limited to along the Mexican border and southwards. Members of the species are songbirds, belonging to the blackbird and oriole family, and the brown-headed variety is abundant from coast to coast in the 48 lower States and southern Canada. They lay their eggs in the nests of birds such as flycatchers, warblers, vireos and sparrows, and are known to have adopted over 200 bird species as their hosts; they are not selective, unlike the cuckoo, and their breeding population is estimated to have increased to 120 million. They inhabit farms, fields and prairies, and centuries ago probably followed the bison herds across the Great Plains to find insect prey flushed up by large grazing animals.
So how do brood parasites on both sides of the Atlantic go about selecting host birds and forcing them to incubate their eggs and rear their chicks? The advantages to the brood parasite are that they are given more time for procreating, finding additional mates and producing a large number of eggs. The typical clutch size for birds is 1 to 5 eggs, with the possibility of additional clutches if there is nest failure.
The female cuckoo annually produces 12 to 22 eggs, usually laying one in different host’s nests and using the same species that reared her. The cowbird is not so picky and is considered a “generalist” when it comes to choosing its foster host. It will lay 30 to 40 eggs each season, one in each host’s nest. Afterwards, the cowbird may remove one or two of the host’s eggs and the remaining ones are left behind. After hatching, it is believed that the begging of the foster siblings results in more food being brought to the nest, allowing the young cowbird to grow up faster. By contrast, the baby cuckoo engages in the murder of its siblings and will eject unhatched eggs and chicks if they have been born. It lifts them onto its back, and after bracing on the sides of the nest, rolls the egg or the chick over the edge to its death. The cuckoo bird is born a serial-killer!
To obtain access to the host nest the brood parasite uses ingenious ways to terrorize its victim and persuade it to raise its offspring. It may wait patiently until the nest owner leaves, and then quickly dart into the nest to deposit an egg. In the case of the common cuckoo bird its appearance resembles that of a bird of prey, with barred underparts and a curved bill, and there is evidence that it uses its outward pretense as a hawk to frighten away the host.
The cuckoo also misleads its host by disguising its egg to look like the host’s egg in color and shape – so the nest owner does not recognize that the egg is foreign. They may also have thicker shells for protection and incubate over a shorter period than the host’s eggs.
Not surprisingly, many hosts do not accept this assault lying down. Some learn to recognize the invaders and go berserk and attack them by landing on them and pecking at them. They may also visually or acoustically recognize the foreign egg and push it overboard, or not incubate it and sometimes abandon the nest altogether. However, not all hosts possess these skills and may simply accept the intrusion and incubate the parasitic egg. Some hosts are too small to push the egg out of the nest and simply build a new nest on top of the old one.
There is no strong evidence that this practice leads to the extermination of host species although brown-headed cowbirds are increasingly abundant and have expanded their range. Springtime trapping is allowed in certain states to control cowbird populations.
An exception to the risk of extermination is the handsome Kirtland’s warbler that came close to disappearing in the 1970’s when, because of loss of habitat as well as nest parasitism by the brown-headed cowbird , its number of breeding pairs fell to 167. The species occupies a small breeding area in parts of Michigan, Minnesota and Wisconsin, and winters in the Bahamas. Because of actions taken to trap the cowbird and plant new Jack Pine forests, the number of breeding pairs is now approaching 1500, and in October 2019 the bird nationally was delisted from the US Endangered Species Act, 1973.
For more on the common cuckoo bird, I refer you to the first chapter of my new novel She Wore a Yellow Dress. And the next time you are accused of having “gone cuckoo”, know that the term comes from the cuckoo’s incessant and pointless calling that is likened to a person who speaks senselessly, monotonously and without purpose (i.e. stupid, barmy, insane). And if you watch One Flew over the Cuckoo’s Nest, recognize that the title is based on an old children’s rhyme featuring three geese – “One flew east, one flew west and the other flew over the cuckoo’s nest” – an apparent reference to a mental hospital where “crazy” or “stupid” people are sent.
But the main story here is brood parasitism. It seems to be a risky reproductive strategy, but for the European cuckoo and the North American cowbird it works. Whether it is egg mimicry, or physical appearance and call mimicry of the chick, or the host’s inability to reject the intrusion, the practice has continued over time and appears unlikely to end. Of 8,600 living species of bird worldwide about 75 are brood parasites, many of them cuckoos, but also included are the South American black-headed duck, African weaver birds and the honeyguides of Africa and Asia.
Eurasian/common teal bird (male) The first Eurasian or common teal I ever saw was a flock flying south over the sea at Spurn Point, Yorkshire, in England, during the early 1960s, presumably on their way to their wintering grounds around the Mediterranean. Spurn Point …
As a small wader and member of the plover family of birds, the dotterel is known for its friendly, sweet and trusting behavior towards humans. Consequently, it was hunted for sport, was easily caught, eaten by royalty as a delicacy during English Tudor times, and …
Eurasian Red-Backed Shrike
I must have been aged 13 at the time during the 1950s, when looking down near the blade of the spade, I spotted a large round object. It was dirty black, except for a distinctive blue-green patina caused by its copper composition. It was heavy and I noticed the vague outline of an official-looking head. My mother asked me to show it to a curator who worked at the York Castle Museum. He informed me it was a valuable Roman artifact, and asked to keep it.
He wanted to exhibit it, and offered me a stuffed red-backed shrike, inside a glass display cabinet, as an exchange. I accepted. I recall there was a date on the back of the case that read 1908. Despite its age, the bird still possessed its bright russet-brown upper parts, dove-grey head, black bandit mask, white throat and underparts tinged pink. The bird belongs to a genus known as “butcher birds” that impale their prey on thorn bushes, and wait until they are hungry and then eat from their “larder”. I have not seen a living red-backed shrike, only its larger cousin, the great grey shrike.
Eurasian Great Grey Shrike
This exchange was one of many events that caused me to become a lifelong birder. If you read my novel (largely memoir), titled She Wore a Yellow Dress, you will gain a better understanding of my hobby. Each chapter is based on a species of bird that I have seen, and describes my early years of bird watching in the 1960s and 1970s.
During the mid 1950s , when the exchange for the Roman coin took place, these small birds-of-prey (slightly larger but slimmer than a house sparrow) were relatively widespread in the UK, though not common. However, by 1989, the species had ceased breeding in Britain. A 1958 York report that I still possess states that “this bird has declined considerably but at no time during the past 80 years can it be said to be common”.
Today these birds are on Britain’s “red list” of endangered species, with about 250 migrating annually along Britain’s east and south coasts. Habitat destruction (scrub clearance), wet weather affecting the birds’ supply of flying insects, early egg collecting, and the continued catching and caging of red-backed shrikes in other countries have caused the decline.
US Northern Shrike
Here in North America, a place that I moved to during 1979, we have two varieties of shrike – the most widespread is the northern shrike, once believed to be a subspecies of the Eurasian and north Africa great grey shrike. It breeds in remote parts of north Canada/Alaska, and winters in the northern United States.
The Loggerhead shrike is similar-looking, but smaller, and typically is seen across the southern US, although travels and breeds as far north as southern Canada. Shrikes from east North America have a pink to medium-gray rump whereas those from the Interior West display a white rump.
There are also a few vagrant Asian brown shrikes that show up along the US West Coast, particularly during the fall migration, and in 2015, a very rare hybrid red-backed shrike was spotted on the Mendocino coast in northern California.
US Loggerhead Shrike
It seems a shame that my original red-backed shrike was persecuted so fiercely, even though hunting and egg collecting are now forbidden. I still look forward to the day when I will see my first living red-backed shrike, and I have no idea if my Roman coin is still on show at the York Museum.
