Bird Fact Friday — Hybrid Gulls

Adapted from page 189 of Gulls Simplified:

Many gull species are closely related, with their evolutionary divergence fairly recent, and their geographic isolation is not always absolute. In fact, the ranges of some genetically similar species overlap. Because of this fertile combination of genetic similarity and physical proximity, hybridization between similar species currently considered distinct is both likely and problematic.

The offspring of theses hybrid combinations often show traits of both parent species, making identification challenging, or may show the physical traits of one species but some plumage features of the other species. Being themselves fertile, these hybrid gulls may then backcross—that is, breed with either parent species or with another hybrid gull—further muddying the ID picture. Hybrids are not countable as distinct species by any ornithological organization.

The Glaucous-winged × Western Gull has the stocky body and heavy bill typical of Western Gull, as well as the head shape of that species with a bump on the crown. However, the back is gray like that of Glaucous-winged, but the wing tips are too dark for that species. Photo credit: Kevin Karlson

For example, the Glaucous-Winged × Western Gull is the most common hybrid gull encountered in North America, and it occurs mostly on the Pacific coast from California to British Columbia. In certain areas of northern Oregon and southern Washington, hybrids may outnumber pure individuals of both species. Some hybrids resemble Western Gulls,especially in body and bill structure, but show some plumage traits of Glaucous-winged, while others resemble Glaucous-winged in structure and bill shape but show some plumage features of Western Gull.

Gulls Simplified
A Comparative Approach to Identification
By Pete Dunne and Kevin Karlson

This unique photographic field guide to North America’s gulls provides a comparative approach to identification that concentrates on the size, structure, and basic plumage features of gulls—gone are the often-confusing array of plumage details found in traditional guides.

Featuring hundreds of color photos throughout, Gulls Simplified illustrates the variations of gull plumages for a variety of ages, giving readers strong visual reference points for each species. Extensive captions accompany the photos, which include comparative photo arrays, digitized photo arrays for each age group, and numerous images of each species—a wealth of visual information at your fingertips. This one-of-a-kind guide includes detailed species accounts and a distribution map for each gull.

An essential field companion for North American birders, Gulls Simplified reduces the confusion commonly associated with gull identification, offering a more user-friendly way of observing these marvelous birds.

  • Provides a simpler approach to gull identification
  • Features a wealth of color photos for easy comparison among species
  • Includes detailed captions that explain identification criteria and aging, with direct visual reinforcement above the captions
  • Combines plumage details with a focus on size, body shape, and structural features for easy identification in the field
  • Highlights important field marks and physical features for each gull

Bird Fact Friday — the Ivory Gull

Adapted from page 177 and 182 of Gulls Simplified:

The Ivory Gull is a “Dark Horse Gull” or, a gull you are most unlikely to encounter in North America, but should be aware of. Some of these may be found at appropriate times of year in very remote locations that average birders don’t typically visit, while others are rare vagrants whose presence cannot be predicted.

An immature Ivory Gull, photographed in New Jersey. Credit: Kevin Karlson

Smaller than Iceland Gull, Ivory Gull is slightly smaller than Ring-billed Gull but stockier and plumper overall. Ivory Gull is our only pure white gull with black legs and black eyes (thus eliminating the possibility of albinism in other species).

Ivory Gull is often described as an aggressive and voracious feeder—a trait that serves a bird that lives very literally on the edge. It is somewhat pigeon-like on land but wheeling and nimble in flight, with quick wing beats. Mostly solitary and somewhat nocturnal, it is reported to investigate anything red. It is always found near water, even cattle watering troughs if nothing more suitable is around.

This distinctive but rarely seen all-white Arctic gull is typically found foraging around pack ice, where it makes a decent living scavenging the remains of polar bear kills. Vagrants often feed on fish scraps near fishing piers or docks where boats dump their bycatch.

They are rarely away from their high Arctic breeding locations with pack ice, in Greenland and extreme northern Canada. In winter, they are found almost exclusively near pack ice, with wintering areas in the Bering Sea and Labrador Sea to Davis Strait. Occurs casually to the Canadian Maritimes and is accidental south to New Jersey and other scattered locations. There are a few inland records, including Tennessee, with most clustered around the Great Lakes. It is very rare south of Canada.

Gulls Simplified
A Comparative Approach to Identification
By Pete Dunne and Kevin Karlson

This unique photographic field guide to North America’s gulls provides a comparative approach to identification that concentrates on the size, structure, and basic plumage features of gulls—gone are the often-confusing array of plumage details found in traditional guides.

Featuring hundreds of color photos throughout, Gulls Simplified illustrates the variations of gull plumages for a variety of ages, giving readers strong visual reference points for each species. Extensive captions accompany the photos, which include comparative photo arrays, digitized photo arrays for each age group, and numerous images of each species—a wealth of visual information at your fingertips. This one-of-a-kind guide includes detailed species accounts and a distribution map for each gull.

An essential field companion for North American birders, Gulls Simplified reduces the confusion commonly associated with gull identification, offering a more user-friendly way of observing these marvelous birds.

  • Provides a simpler approach to gull identification
  • Features a wealth of color photos for easy comparison among species
  • Includes detailed captions that explain identification criteria and aging, with direct visual reinforcement above the captions
  • Combines plumage details with a focus on size, body shape, and structural features for easy identification in the field
  • Highlights important field marks and physical features for each gull

 

Luke Hunter on Carnivores of the World

Covering all 250 species of terrestrial, true carnivores, from the majestic polar bear and predatory wild cats to the tiny least weasel, Luke Hunter’s comprehensive, up-to-date, and user-friendly guide, Carnivores of the World, features 93 color plates by acclaimed wildlife artist Priscilla Barrett that depict every species and numerous subspecies, as well as more than 400 drawings of skulls and footprints. Features new to this edition include revised and expanded species coverage, a distribution map for every species, 25 new behavioral illustrations, and much more. Detailed species accounts describe key identification features, distribution and habitat, feeding ecology, behavior, social patterns, reproduction and demography, status, threats, lifespan, and mortality. An introduction includes a concise overview of taxonomy, conservation, and the distinct families of Carnivora.

What’s new in the second edition?

The text has been completely revised for the second edition, with new data and observations published since 2011 to update and improve the original text throughout. By way of one example, most reproductive data for the Andean Bear in the first edition had been collected from captive animals, but the first population-level information from long-term research on the species in the wild (in Peru) was published in 2018, and has been incorporated in the book. Similarly, some species which were very poorly known at the time I wrote the first edition have since been the focus of at least one dedicated research effort, providing much better information for the new book; examples include the Bush Dog, Fishing Cat and Narrow-striped Boky.

A major addition in the new edition is the inclusion of 9 new species delineated since 2011, largely as a result of recent genetic analyses. Perhaps the most dramatic example is the African Wolf, formerly believed to be an African population of the Eurasian Golden Jackal.  The new book covers numerous cases where one species has been re-classified into two or even three, e.g. European, Asian and Japanese badgers, Northern and Southern Oncillas, and Mainland and Sunda Leopard Cats.

Finally, the IUCN Red List category indicating degree of endangerment has been revised for most carnivores, I provide a new assessment of Population Trend for each species, and the second edition includes distribution maps for every species based on the most recent IUCN Red List population data.

It is surprising that so many new species have been described since the first edition was published. How did these discoveries arise?

All new species in the book arose largely as a result of advances in genetic technology which has made very powerful and cost-effective analyses widely accessible to researchers. It has allowed geneticists to look with ever-increasing resolution at the differences between populations which, in some cases, turned out to be a so-called “cryptic species.” The same process has also revealed cases where populations formerly considered to be separate species (based mainly on appearance) actually have minor genetic differences, subsuming two former species into one. For example, Grandidier’s Vontsira is now regarded as a distinct population of the Broad-striped Vontsira. Whereas the first edition included accounts of 245 species, edition 2 covers 250 species, nine of them newly described.

To many readers, uncovering new species by genetic differences probably does not have the same excitement as news of an entirely unknown animal never before seen by scientists being discovered in a remote corner of the globe. Do you think the new species in the book are as interesting or even valid?

The question of validity is an interesting one; even geneticists debate the degree of genetic divergence indicative of two distinct species (versus lower-level delineations, for example, indicative of sub-species). There is the genuine danger of a ‘gold-rush’ in which researchers rush to publish new discoveries based on relatively minor distinctions between populations: there are already examples in the scientific literature. I took a conservative approach in the book, and included only those new species supported by strong published evidence and that are generally accepted by relevant authorities e.g. the International Union for Conservation of Nature Species Survival Commission (IUCN SSC) Specialist Groups devoted to carnivores.

Even with that, the question of validity remains a moving target. I believe that any newly discovered genetic distinctions must reflect other significant biological differences, such as in morphology, ecology, distribution and especially in reproductive isolation, the classic (some say old-fashioned!) defining characteristic of species. This is not always well understood, even for some of the new species included in this new edition. In an introductory section on the 13 families of terrestrial carnivores, I list other cases that I consider borderline or questionable; these are not treated as full species in the book but some may eventually be recognized as such with better data and analyses in future. This is a story that will continue to unfold.

Priscilla Barrett’s artwork is superb, with many species which have never been so accurately and beautifully painted. What was it like working with her?

Priscilla is an exceptional collaborator. With her zoology background, she brings a scientist’s rigor to the process. She draws on her vast collection of reference material- photos of museum skins and samples, sketches and notes from the field- and we also used hundreds of recent camera-trap images, supplied by colleagues from around the world, including of many species or forms that have otherwise never been photographed in the wild. The result is art that is not only beautiful but also highly accurate; viewing Priscilla’s carnivores, I always feel a surge of recognition, that she has captured the true essence of each species.

Beyond each individual piece of art, each plate benefits from Priscilla’s very intuitive sense of design. The process started with her sketching rough lay-outs to decide the poses for each species or form, and how each interacted with the others on the page. Once we had decided that a plate worked, she painted all of the components. It has been very rewarding for me to come to understand how that process produces complete plates with both balance and life.

Field guides to mammals are becoming more common. Do you think this reflects greater interest in watching mammals?

Two colleagues who recently published a review of mammal-watching put it nicely when they said ‘Mammalwatching today is arguably where bird-watching was a century ago.’ That said, the same paper notes how mammal-focused tourism has increased dramatically in the last couple of decades, not only for the large charismatic species that every safari-goer to Africa wants to see, but increasingly for small and often difficult-to-see species requiring specialist guides and local knowledge.

Amateur mammal-watchers have also contributed to scientific discoveries including the first documented record, with terrific photos, of the virtually unknown Pousargues’ mongoose in Uganda since the 1970s, and the first records of Pale Fox and Rüppell’s Fox from northeastern Ethiopia; I referred to both papers for the second edition. I also had access to many dozens of trip reports written by mammal-watchers since the first edition. There’s little doubt all this reflects an increase in mammal-focused tourism, a trend that I am sure will continue. And one, I hope, that helps foster the growing demand for more and better mammal-focused field guides!

 

Luke Hunter is one of the world’s leading authorities on wild carnivores. His books include Wild Cats of the World and Cheetah. He lives in New York City.

Bird Fact Friday — the Great Black-Backed Gull

Adapted from page 155 & 158 of Gulls Simplified:

This very large, menacing-looking gull (it truly is the largest gull in the world) has a big, squarish or oval-shaped head and a heavy bill. This barrel-chested gull is typically noticeably larger and always chestier than Herring Gull, with a larger, broader head, thicker neck, and distinctly heavier bill. Dull pink legs are long, thick, and set at midspan, accentuating the bird’s barrel-chested appearance.

Adults have a dark charcoal to black back and a white head, while immature birds are spangled or granite patterned with gray, white, and black upperparts and a white head. This contrasting pattern stands out among the brownish-gray immatures and gray-backed adult ranks of Herring Gulls.

Great Black-backed is a fairly sedentary gull, spending much of its time loafing on the beach, resting on the water, or standing atop an elevated post or light fixture. It walks somewhat reluctantly, with a waddling sailor’s gait. This species generally dominates other gulls when food is available and frequently displaces other gulls from prime perches. It is often found with other large, white-headed Gulls, especially Herring Gulls. Much smaller Ring-billed Gulls go out of their way to avoid any interaction with this species.

Great Black-backed Gull is typically the largest and huskiest gull on the Atlantic
beachfront or Great Lakes shorelines, or anywhere else it is found, since it is the largest gull in the world. Photo credit: Kevin Carlson

A consummate kleptoparasite (stealer of another’s food), Great Black-backed often robs cormorants, other gulls, and seabirds of fish and other food items. This species is also highly predatory. It is known to harass diving birds, such as coots (which can’t stay underwater very long), to exhaustion and then grasp the debilitated bird by the head, killing it outright or, failing that, drowning its victim. Kevin [Karlson, co-author of Gulls Simplified] once saw an adult Great Black-backed kill and swallow whole a Northern Flicker that had been sitting exhausted on a beach in New York during fall migration.

This is a fairly common gull that is typically found on Atlantic coast beaches, where it is a resident species, as well as on the Great Lakes, where it is also resident and increasing in numbers. Lesser numbers are found south to Florida (mostly on the Atlantic coast), where it is also increasing.

Gulls Simplified
A Comparative Approach to Identification
By Pete Dunne and Kevin Karlson

This unique photographic field guide to North America’s gulls provides a comparative approach to identification that concentrates on the size, structure, and basic plumage features of gulls—gone are the often-confusing array of plumage details found in traditional guides.

Featuring hundreds of color photos throughout, Gulls Simplified illustrates the variations of gull plumages for a variety of ages, giving readers strong visual reference points for each species. Extensive captions accompany the photos, which include comparative photo arrays, digitized photo arrays for each age group, and numerous images of each species—a wealth of visual information at your fingertips. This one-of-a-kind guide includes detailed species accounts and a distribution map for each gull.

An essential field companion for North American birders, Gulls Simplified reduces the confusion commonly associated with gull identification, offering a more user-friendly way of observing these marvelous birds.

  • Provides a simpler approach to gull identification
  • Features a wealth of color photos for easy comparison among species
  • Includes detailed captions that explain identification criteria and aging, with direct visual reinforcement above the captions
  • Combines plumage details with a focus on size, body shape, and structural features for easy identification in the field
  • Highlights important field marks and physical features for each gull

 

Bird Fact Friday — Western Gulls

Adapted from pages 143-146 of Gulls Simplified:

A large gull with an overall stocky, robust profile, Western Gull is about the same size as Herring and Glaucouswinged Gulls, but adults show a darker, charcoal-gray back. The large head supports a stout, bulbous-tipped bill (smaller and straighter on some birds) and a curious bump or peak on the head (just above the eye, or sometimes above the nape)  that makes the head of Western Gull more convex (rounded) than the overall thinner head and drawn-out face of Herring Gull. The bill of Western typically appears thicker, shorter, and more bulbous tipped compared to Glaucous-winged’s longer, straighter bill, with the exception of some smaller Westerns that have slender bills. Standing birds with neck retracted often appear to slouch. When birds are standing, wing tips extend well beyond the tail and are often elevated, leaving a slight gap between wings and tail.

Western mixes freely with other gulls, especially Glaucous winged, and is often found where humans concentrate. It feeds primarily by scavenging over ocean waters for marine invertebrates. Its large size and bulky profile result in dominance over most gulls in its range. A Western Gull standing atop some elevated point on an ocean pier is a typical and iconic image. In the wave zone, it typically forages alone. 

Western and Ring-billed Gulls, adult. Photo credit: Kevin Karlson.

Two subspecies exist in Western Gull, with subspecies occidentalis occurring in northern California and farther north, and subspecies wymani occurring in southern California and farther south. Southern-breeding birds have a slightly darker back than northern ones, but recognition of this shading difference requires a good amount of study and exposure to both, and birds in the broad overlap zone show intermediate gray shading.

A common and highly coastal West Coast gull, the default dark-backed gull of the West Coast. Breeding range is from the central Washington State coastal zone south to the coastal zone of the central Baja California Peninsula, Mexico. Winter range includes the breeding range and smaller areas north to the Canadian border and south to the southern tip of Baja, as well as the northern Gulf of California.

In winter on California beaches, Western is typically the most numerous gull species. If you are standing on a California beach and you are looking at a large, dark-backed gull, STOP; you are most likely looking at an adult or 3rd winter Western Gull. Western Gull also frequents landfills, harbors, lakes, and rivers. No other large, charcoal gray–backed gull typically occurs within its range along the Pacific coast.

Gulls Simplified
A Comparative Approach to Identification
By Pete Dunne and Kevin Karlson

This unique photographic field guide to North America’s gulls provides a comparative approach to identification that concentrates on the size, structure, and basic plumage features of gulls—gone are the often-confusing array of plumage details found in traditional guides.

Featuring hundreds of color photos throughout, Gulls Simplified illustrates the variations of gull plumages for a variety of ages, giving readers strong visual reference points for each species. Extensive captions accompany the photos, which include comparative photo arrays, digitized photo arrays for each age group, and numerous images of each species—a wealth of visual information at your fingertips. This one-of-a-kind guide includes detailed species accounts and a distribution map for each gull.

An essential field companion for North American birders, Gulls Simplified reduces the confusion commonly associated with gull identification, offering a more user-friendly way of observing these marvelous birds.

  • Provides a simpler approach to gull identification
  • Features a wealth of color photos for easy comparison among species
  • Includes detailed captions that explain identification criteria and aging, with direct visual reinforcement above the captions
  • Combines plumage details with a focus on size, body shape, and structural features for easy identification in the field
  • Highlights important field marks and physical features for each gull

 

Bird Fact Friday — Sabine’s Gull

Adapted from pages 69-70 of Gulls Simplified:

A small, trim gull that is smaller than a kittiwake or Mew Gull and most commonly seen in flight over ocean waters (less commonly found sitting on beaches with similarly sized gulls). In flight, Sabine’s appears short bodied, with broadbased, angular wings and a fairly long, uniquely forked tail. 

The bold tricolored upper wing pattern (black, white, and gray) is somewhat similar to that of other species but is distinctly bolder on Sabine’s and thus more visually grabbing. Stiff, shallow, steady wing beats reveal flashes of the bird’s wedge-like white wing patch. Flight is overall lofting and buoyant, but not as nimble or tern-like as that of Bonaparte’s Gull.

Sabine’s forages mostly by swimming and snatching prey from the surface of the water while at sea, and it feeds in shallow pools at breeding sites by stirring up aquatic invertebrates by stomping the substrate with its feet (see Sabine’s Gull 1). It does not respond to chum as readily as kittiwakes on pelagic birding trips. It also hovers and plucks prey from the surface. When foraging on beaches, Sabine’s walks nimbly.

This small, smart-looking, Arctic-breeding gull with a deep charcoal hood going blacker at the collar and front of the face is unique. Photo credit: Kevin Karlson.

In migration, birds resting on the water gather in tight (typically small) clusters. Sabine’s is fairly tame while on the water, allowing close approach by boats before flushing. On West Coast pelagic trips, Sabine’s Gulls are usually seen in small groups. In the interior, single birds are the norm, and these may mix with Bonaparte’s Gulls.

This localized Arctic breeder is fairly common during migration in fall, primarily in offshore northern to central Pacific coastal North American waters; very rare along East Coast in fall. Winter records are extremely rare in North America, with only a few instances of birds remaining until January. Subadult (1st winter) birds typically remain in southern waters until their 2nd year. 

This handsome, mostly pelagic gull breeds in Arctic and subarctic regions but winters in tropical seas off western South America and southern Africa. In North America, it breeds in coastal tundra of western Alaska, the North Slope, and islands of the Canadian Arctic Archipelago, which are far from most human population centers. It also breeds in northern and central Greenland.

There are numerous records of Sabine’s Gulls in the North American interior, mostly in fall, and regular records in the Great Plains and Great Basin regions (Gulls of the Americas, Howell and Dunn, 2007). Fall migration is from late July through October; spring migration is from March through May (occasionally into June).

Gulls Simplified
A Comparative Approach to Identification
By Pete Dunne and Kevin Karlson

This unique photographic field guide to North America’s gulls provides a comparative approach to identification that concentrates on the size, structure, and basic plumage features of gulls—gone are the often-confusing array of plumage details found in traditional guides.

Featuring hundreds of color photos throughout, Gulls Simplified illustrates the variations of gull plumages for a variety of ages, giving readers strong visual reference points for each species. Extensive captions accompany the photos, which include comparative photo arrays, digitized photo arrays for each age group, and numerous images of each species—a wealth of visual information at your fingertips. This one-of-a-kind guide includes detailed species accounts and a distribution map for each gull.

An essential field companion for North American birders, Gulls Simplified reduces the confusion commonly associated with gull identification, offering a more user-friendly way of observing these marvelous birds.

  • Provides a simpler approach to gull identification
  • Features a wealth of color photos for easy comparison among species
  • Includes detailed captions that explain identification criteria and aging, with direct visual reinforcement above the captions
  • Combines plumage details with a focus on size, body shape, and structural features for easy identification in the field
  • Highlights important field marks and physical features for each gull

Bird Fact Friday — Franklin’s Gull

Adapted from pages 44-46; 49 of Gulls Simplified:

This small, gregarious, petite-billed, and blackheaded breeder of the western interior suggests a smaller, stockier Laughing Gull, with a shorter, straighter bill, shorter legs, and conspicuously shorter, round-tipped wings. Franklin’s also has a rounder head with more prominent white eye arcs and boldly patterned black outer wings with large white spots (mirrors) near the tip of the outer primaries (adults). Franklin’s are agile gulls, able to hop over obstacles and perch on cattails.

During the breeding season, they hawk insects over marshes, and in migration often forage on tilled agricultural land. When foraging for aquatic insects on lakes, they behave like a swimming phalarope, plucking insects from the surface. In some locations, migrating flocks may number in the thousands. Franklin’s Gulls forage on beaches, inshore waters, lakeshores, and dry or flooded fields, and they nest in freshwater marshes. They are often found in small homogeneous flocks, but inland they may mix with California Gulls. In migration on the Gulf coast, they often roost and rest with Laughing Gulls.

Adult, non breeding Franklin’s Gulls. They are typically 13.25-15 inches long, with a wingspan of 33-36 inches. Photo credit: Kevin Karlson

Common in appropriate habitats, it breeds for the most part in small to very large colonies in inland marshes and lakes on the prairies, in the Great Basin, and in the northern Rocky Mountains. 

Breeding colonies may number in the hundreds, or as many as twenty-five thousand pairs, which occurred at the Lake Alice National Wildlife Refuge in North Dakota in 2000 (North Dakota Game and Fish Department website, 2017). 

During migration, Franklin’s is common to abundant from August to October through its main migratory corridor south through the Great Plains, and also along the Texas lowland coastal areas from mid-October through November (Gulls of the Americas, Howell and Dunn, 2007). Migratory  flocks at this coastal Texas location can number in the many thousands, and Kevin witnessed a flock of over six thousand birds at South Padre Island, Texas, in early November 2003. Migration through the interior is often spread out, with migrating birds widely dispersed until larger numbers gather at nighttime roosts on bodies of water. Winter range is primarily coastal regions of western South America.

This species has experienced a notable decline over the last fifty years (78 percent) according to North American Breeding Bird Atlas data, but population numbers and concerns vary according to individual research papers.

Gulls Simplified
A Comparative Approach to Identification
By Pete Dunne and Kevin Karlson

This unique photographic field guide to North America’s gulls provides a comparative approach to identification that concentrates on the size, structure, and basic plumage features of gulls—gone are the often-confusing array of plumage details found in traditional guides.

Featuring hundreds of color photos throughout, Gulls Simplified illustrates the variations of gull plumages for a variety of ages, giving readers strong visual reference points for each species. Extensive captions accompany the photos, which include comparative photo arrays, digitized photo arrays for each age group, and numerous images of each species—a wealth of visual information at your fingertips. This one-of-a-kind guide includes detailed species accounts and a distribution map for each gull.

An essential field companion for North American birders, Gulls Simplified reduces the confusion commonly associated with gull identification, offering a more user-friendly way of observing these marvelous birds.

  • Provides a simpler approach to gull identification
  • Features a wealth of color photos for easy comparison among species
  • Includes detailed captions that explain identification criteria and aging, with direct visual reinforcement above the captions
  • Combines plumage details with a focus on size, body shape, and structural features for easy identification in the field
  • Highlights important field marks and physical features for each gull

Bird Fact Friday—Bonaparte’s Gull

Adapted from page 50 of Gulls Simplified:

Bonaparte’s is delicately proportioned overall, with a long-winged profile; a small, round head; and a petite, short, thin, straight, pointy, tern-like bill. In feeding flight, they often impart a potbellied profile when dipping down to the water’s surface to gather food. Initial confusion with terns is not just possible but likely because of their size, physical resemblance, and buoyant flight style. Legs are relatively short compared to those of other North American hooded gulls other than Little Gull.

An adult Boneparte’s Gull, photographed in Churchill, Manitoba around June. This bird is usually 12.3-13.8 inches long, with a wingspan between 30-36 inches.
Photo credit: Kevin Karlson.

In flight, adults show a flashing white triangle on the leading edge of the outer wing, while 1st winter birds have reduced white on the underwing primary tips and black shafts and markings on a white outer wing triangle. Adults have uniformly pale silvery-gray upperparts and white underparts, making the black trailing edge to the outer wing and the black bill stand out.

Bonaparte’s is a small, petite gull with a dainty black bill. This complete breeding plumage is not regularly seen in parts of North America and is seen only briefly at normal migratory locations from April to May. Note the all-black hood (brown in Black-headed Gull), bold white eye arcs, and petite black bill (reddish to black in Black-headed). These nimble gulls commonly perch on elevated platforms, where the pink legs of adults are evident.

 

Gulls Simplified
A Comparative Approach to Identification
By Pete Dunne and Kevin Karlson

This unique photographic field guide to North America’s gulls provides a comparative approach to identification that concentrates on the size, structure, and basic plumage features of gulls—gone are the often-confusing array of plumage details found in traditional guides.

Featuring hundreds of color photos throughout, Gulls Simplified illustrates the variations of gull plumages for a variety of ages, giving readers strong visual reference points for each species. Extensive captions accompany the photos, which include comparative photo arrays, digitized photo arrays for each age group, and numerous images of each species—a wealth of visual information at your fingertips. This one-of-a-kind guide includes detailed species accounts and a distribution map for each gull.

An essential field companion for North American birders, Gulls Simplified reduces the confusion commonly associated with gull identification, offering a more user-friendly way of observing these marvelous birds.

  • Provides a simpler approach to gull identification
  • Features a wealth of color photos for easy comparison among species
  • Includes detailed captions that explain identification criteria and aging, with direct visual reinforcement above the captions
  • Combines plumage details with a focus on size, body shape, and structural features for easy identification in the field
  • Highlights important field marks and physical features for each gull

Bird Fact Friday —The Laughing Gull

Adapted from pages 35-37 of Gulls Simplified:

A flock of adult Laughing Gulls, photographed in New Jersey in May. Photo credit: Kevin Karlson

This lanky gull stands with a horizontal profile and shows black wing tips that are acutely pointed and extend well beyond the tail. A long, slender bill droops near the tip. Long, typically black legs are set moderately forward, with some birds showing dull to fairly bright red legs in the breeding season. The dark hood is replaced by a mostly white head with a dark ear patch and scattered dark markings on the crown in winter. 

On beaches and in the water, they tend to gather in tightly bunched monotypic flocks away from larger gulls. In mixed-species flocks, Laughing Gulls often segregate to one side. Very agile and aerial, this species is adept at snapping insects out of the air and may gather in wheeling numbers over  marshes and uplands when an insect hatch is in progress. They are also a threat to coastal tern colonies and beach-nesting shorebirds, since they can swoop in and grab an egg or small chick before the defending birds can react to their approach. The bird’s loud, raucous (laughing) call is iconic, as much a part of a visit to coastal beaches and marshes as the sound of surf and the tang of salt-laden air. The sound of feeding flocks approaches the level of a din. Breeding colonies are noisy, even at night.

Skilled foragers, Laughing Gulls are adept at plucking food from human hands, whether the morsel is offered or not, and they seem to know all about picnic baskets, potato chip bags, and their contents. Very social and vocal, Laughing Gulls also forage offshore in large aggregations, usually within sight of land, where noisy feeding flocks hover and wheel over schools of baitfish. They commonly pursue other gulls and seabirds to steal food.

While most commonly found on sandy beaches, Laughing Gulls also frequents tidal wetlands, plowed fields, parks, and picnic areas. You may also share your hotel swimming pool with these birds in coastal areas with warm climates as they drop by for a drink or a swim. Though mostly coastal year-round, individuals are occasionally found well inland, most commonly on freshly turned agricultural land, landfills, and the parking lots of food outlets.

 

Gulls Simplified
A Comparative Approach to Identification
By Pete Dunne and Kevin Karlson

This unique photographic field guide to North America’s gulls provides a comparative approach to identification that concentrates on the size, structure, and basic plumage features of gulls—gone are the often-confusing array of plumage details found in traditional guides.

Featuring hundreds of color photos throughout, Gulls Simplified illustrates the variations of gull plumages for a variety of ages, giving readers strong visual reference points for each species. Extensive captions accompany the photos, which include comparative photo arrays, digitized photo arrays for each age group, and numerous images of each species—a wealth of visual information at your fingertips. This one-of-a-kind guide includes detailed species accounts and a distribution map for each gull.

An essential field companion for North American birders, Gulls Simplified reduces the confusion commonly associated with gull identification, offering a more user-friendly way of observing these marvelous birds.

  • Provides a simpler approach to gull identification
  • Features a wealth of color photos for easy comparison among species
  • Includes detailed captions that explain identification criteria and aging, with direct visual reinforcement above the captions
  • Combines plumage details with a focus on size, body shape, and structural features for easy identification in the field
  • Highlights important field marks and physical features for each gull

 

Dale Dyer on the Art of Illustrating Field Guides

I’ve been drawing and painting birds for books for about 25 years now. It seems like a long time, but it took me a while to get there. When I was a kid, Don Eckelberry was my hero – he was the illustrator for the Audubon Field Guide and the Guide to Birds of the West Indies by James Bond (real, not fictional) – and my dream was to become a bird illustrator. By the time I went to art school, however, I was enthralled by the great painting of the past and was determined to find a way to make great art in the present. Birdwatching and bird drawing were set aside. Perhaps the accompanying studio self-portrait (left) shows the ambition and angst associated with that preoccupation.

I eventually found myself back in the woods, the shore and the mudflats with my binoculars anyway. More than expressing myself, I wanted to express something about the world. I started to teach myself the birds by drawing them.

I’m interested in communicating not only the experience of an encounter with nature, but also a scientific understanding of it. Though I have no formal training in ornithology, I have always had a serious interest in taxonomy and biodiversity. I am currently a Field Associate of the Ornithology Department of the American Museum of Natural History in New York, and have been working in that collection for fifteen years. That is an education in of itself, and I have had the privilege of meeting and talking with ornithologists from all over the world.

A field guide is a portrait of the biodiversity of a region. When the illustrations are designed well, and combined with accurate range maps, biogeographic patterns emerge with special clarity. Thorough review of bird specimens from across Central America, as well as a review of ornithological literature, is what gives me an understanding of what needs to be said, and inspires me to get to the drawing board.

The only way to study geographic variation in a species is by placing specimens from far apart places side by side. A great collection like that at the AMNH gives one an opportunity to study species and species relationships in a way that watching birds in the field can not. Nevertheless, it necessary to combine field experience with museum experience to create a vivid and accurate image of a species.

Over the ten-year course of working on Birds of Central America, I traveled nearly every year. I wish it could have be more – some of my experience with a species feels like just a little taste, and there are quite a few species in the book that I have never seen. Bird illustration, however, requires not only observation and reproduction skills, but research and re-creation skills. I’d love to see them all, but work which requires a lifetime of preparation never gets done. Painting a book requires a tremendous amount of time just sitting in your chair working.

Leafing through a field guide gives one a sense of what exists, what is fragile, what needs to be preserved, and also fills the traveling birder with an excitement in anticipation of what they may encounter. I like making art for books because books are affordable, accessible to all, and because I know how intently birders look at the pictures. No one painting for gallery exhibitions can depend on the kind of focused attention to their work that I get.

 

Dale Dyer  is an ornithological illustrator who has contributed to many books on birds, including Birds of Peru and All the Birds of North America. Dyer, along with his co-author Andrew C. Vallely, are currently field associates in the Department of Ornithology at the American Museum of Natural History.

Galápagos: Animals Interacting

Adapted from pages 172-183 of Galápagos: Life in Motion:

Alpha male Galápagos Sea Lion patrolling his beach, Fernandina Island. Photo credit: Walter Perez.

Galápagos animals strive to cope with their harsh environment. This often means struggling to find food when it is scarce, hiding from predators, and finding a mate. But much of the life of an animal involves dealing with other animals. Sometimes it is necessary to fight, but sometimes play is welcome. Some animals depend on each other through various cooperative mutualisms, while other curious animals keep a careful eye on the humans who have recently arrived in their environments. Animals are intimately part of each other’s environments, and no examination of animal behavior would be complete without understanding these relationships.

One of the most dramatic interactions among Galápagos animals is fighting—for territory, access to mates, or food. Iguanas are territorial and fight to protect their territory, and their mating success is tied to the quality of the territory they hold. Many instances of fighting ultimately are about mating. Although Waved Albatrosses form mating pairs, additional copulation is common and often a source of skirmishes. Similarly, large male Galápagos Sea Lions will protect their beaches for weeks at a time, preventing other males from gaining sexual access to females.

In the most barren and dry parts of the Galápagos, access to preferred nesting and feeding grounds can mean the difference between successfully raising offspring or not. There are often spirited disagreements over who can lay their eggs and who can feed in a given location. Not every interaction between animals is brutal, however. Galápagos animals play with members of their own species, with other animals, and even with plants and sticks.

Galápagos: Life in Motion
by Walter Perez & Michael Weisberg

The Galápagos Islands are home to an amazing variety of iconic creatures, from Giant Tortoises, Galápagos Sea Lions, Galápagos Penguins, and Ghost Crabs to Darwin’s finches, the Blue-footed Booby, and Hummingbird Moths. But how precisely do these animals manage to survive on—and in the waters around—their desert-like volcanic islands, where fresh water is always scarce, food is often hard to come by, and finding a good mate is a challenge because animal populations are so small? In this stunning large-format book, Galápagos experts Walter Perez and Michael Weisberg present an unprecedented photographic account of the remarkable survival behaviors of these beautiful and unique animals. With more than 200 detailed, close-up photographs, the book captures Galápagos animals in action as they feed, play, fight, court, mate, build nests, give birth, raise their young, and cooperate and clash with other species.

Watch male Marine Iguanas fight over territory and females; see frigatebirds steal food and nesting materials from other birds; witness the courtship dance of a pair of Blue-footed Boobies; go underwater to glimpse a Galápagos Sea Lion pup playing with its mother; and observe a baby Pacific Green Turtle enter the water for the first time. These and dozens of other unforgettable senes are all vividly captured here—including many moments that even experienced Galápagos observers may never be lucky enough to see in person.

Complete with a brief text that provides essential context, this book will be cherished by Galápagos visitors and anyone else who wants to see incredible animals on the move.

Bird Fact Friday—Tinamous

Adapted from pages 28-29 of Birds of Central America:

Drawings of the Great Tinamou (top 4 birds), and the Highland Tinamou (bottom two birds).

Tinamous are short-tailed, terrestrial birds, found mainly in humid broadleaf forest. They are sensitive to hunting pressure and can be difficult to see as they quickly walk away at the approach of an observer. In less humid areas, tinamous can sometimes be located by the scratching sound produced as they walk over dry leaf litter. Most are detected by voice.

The Great Tinamou (Tinamus major) is the most common and widespread.  They are 44 cm tall, and are fairly common residents in lowlands and foothills (to 1800 m). These birds can be identified by their gray legs and white throat, mostly brownish barred with dusky on upperparts and flanks, and are grayish below with fine barring on flanks. Most often detected by voice during early morning or dusk, and sometimes calls from elevated roost site. Individuals, pairs, or small groups can be located by listening for rustling sounds produced as they forage or walk in dry leaf litter. Their call is two to four paired, long, tremulous whistles. First note usually slightly lower-pitched and sometimes repeated two or three times. Second note drops in pitch.

Meanwhile, the Highland Tinamou (Nothocercus bonapartei) are uncommon residents in foothills and highlands (above 1200 m). These are fairly large (40cm) birds, with  gray legs, and dark gray crown and sides of head. The birds’ underparts are cinnamon, becoming brightest on throat and belly, and narrowly and sparsely barred with dusky. They have Dark rufous-brown above with fine blackish vermiculations and variable buff spotting on wings. Some have buff spotting extending to rump and mantle. They are, more often than not, solitary or in pairs, secretive and rarely seen. Most often detected by voice , with a call that sounds like a short, hoarse, low-pitched huh-wowr or unh-heer, which it sometimes repeats steadily.

Birds of Central America
Belize, Guatemala, Honduras, El Salvador, Nicaragua, Costa Rica, and Panama

By Andrew C. Vallely and Dale Dyer

Birds of Central America is the first comprehensive field guide to the avifauna of the entire region, including Belize, Guatemala, Honduras, El Salvador, Nicaragua, Costa Rica, and Panama. Handy and compact, the book presents text and illustrations for nearly 1,200 resident and migrant species, and information on all rare vagrants. Two hundred sixty detailed plates on convenient facing-page spreads depict differing ages and sexes for each species, with a special focus on geographic variation. The guide also contains up-to-date range maps and concise notes on distribution, habitat, behavior, and voice. An introduction provides a brief overview of the region’s landscape, climate, and biogeography.

The culmination of more than a decade of research and field experience, Birds of Central America is an indispensable resource for all those interested in the bird life of this part of the world.

  • Detailed information on the entire avifauna of Central America
  • 260 beautiful color plates
  • Range maps, text, and illustrations presented on convenient facing-page spreads
  • Up-to-date notes on distribution supported by an extensive bibliography
  • Special focus on geographic variation of bird species