#olrog's gull

[bestgullpoll]

Round 2, Side A: Match 28

[Image ID: Two pictures of gulls. The left is a Heerman's gull standing on sand. The right is an Olrog's gull standing in water. /End ID]

The Heermann's gull (Larus heermanni) is found along the west coast of the United States, Mexico, and southwestern Canada. They typically measure 46-53 cm (18-21 in) in length and 104-115 cm (41-45 in) in wingspan. They have a grey body, dark grey wings and tail with white edges, black legs, and red bill with black tip. Their head is white in breeding plumage. They eat mainly small fish, as well as marine invertebrates, lizards, insects, and carrion. They have an unusual "backwards" migration, nesting in the southern part of their range and migrating northward during nonbreeding season. About 90% of their ~150,000-pair population nest on the single island of Isla Rasa in the Gulf of California. This makes them vulnerable to catastrophic weather events, so they are listed as near threatened by the IUCN.

The Olrog's gull (Larus atlanticus) is a large gull that lives along the Atlantic coast of southern Brazil, Uruguay, and Argentina. They typically measure 50-60 cm (20-24 in) in length and 130-140 cm (51-55 in) in wingspan. They have white underparts and head, black back and wings, yellow legs, yellow bill with red and black tip, and white tail with black band. They eat crabs, giving them the name gaviota cangrejera or "crab-eater gull" in their native range, as well as molluscs, fish, and insects. They are listed as near threatened by the IUCN.

Heermann's gull image by Dick Daniels

Olrog's gull image by Cristiano Crolle

[ethanm8n]

Gulls

March 19, 2024

“I was mugged by a gang of seagulls” reads the title of a Tripadvisor review for Granville Island1. “When I came outdoors [a] gang of seagulls attacked me and stole part of my lunch.” Anyone who has eaten a meal outside of the Granville Island Public Market will understand this frustration. Seagulls watch like sentinels from rooftops, above benches and dining tables, on the lookout for a loose pizza slice; grey-coloured seagulls beg near sitting diners, screeching incessantly. Some seagulls patrol the skies above, while others choose to stay close to the ground, walking around on webbed-feet, waiting for loose food items and handouts. It would be easy to overlook these birds as a nuisance—rats with wings, to quote the pelican from Finding Nemo. They may be kleptoparasites, stealing food from other animals, including lunching humans and unsuspecting tourists. But seagulls are so much more than just ratbirds. In the Salish Sea region, they humble the proudest of birders trying to make an ID. (Is that light grey-mantled gull with darkish grey wingtips a Western x Glaucous-winged Gull hybrid or a darker Glaucous-winged Gull? Does the slightly smaller, petite head indicate hybridization with a Herring Gull, or is it a female of another species? Is its eye colour dark or pale? How about the colour of the orbital rings?) Their increasing reliance on urban breeding grounds (e.g. rooftops) serves as a litmus test for habitat degradation, and also gives researchers an opportunity to study how fauna adapt to urban living. How does the diet of an urban dwelling Glaucous-winged Gull Larus glaucescens differ from one that spends its time in more remote areas? Do urban seagulls lay more or less eggs than their counterparts? What is the survival rate of their young in to adulthood? Researchers have been hard at work answering these questions2. One recent study flew drones above buildings in Victoria to study nest sites of Glaucous-winged Gulls, a wonderful example of new technology opening up more avenues for scientific inquiry3.

Before going further, I need to address a misnomer. Gulls belong to a diverse group of birds in the family Laridae, from the circumpolar, all white Ivory Gull Pagophila eburnea, to the grey-bodied Lava Gull Leucophaeus fuliginosus and coal-black backed Olrog's Gull Larus atlanticus in South America. (Melanin—the pigment responsible for skin colour in humans—is what gives darker tones to feathers. It helps resist sun bleaching, which is why gull species's upper bodies trend towards darker tones closer to the equator4.) The Heermann's Gull Larus heermanni is a true pelagic (literally “ocean”) species, individuals spending their days hunting for fish, rarely going inland. Then there is the California Gull Larus californicus, which breeds inland of the Western United States; and the Ring-billed Gull Larus delewarensis, prolific in most of North America, but rarely straying beyond coastal waters5. This is why you will almost never hear birders refer to seagulls as such. Many gulls are generalists, found in urban centres, prairies, rivers and lakes, landfills, open oceans and coastlines. Calling them seagulls would be a disservice to their enterprising nature, breeding on every continent, including on the fringes of Antartica. Many of these species have adapted to living in rapidly expanding human-made habits. We can conflate this success with the annoyance conjured up in many people's minds when they think of these birds: Their pervasiveness; their loud squawking; the mess they make with their guano; and their proclivity towards thievery. Perhaps the things humans find so irritating about gulls are actually what we hold most in common. But I digress. No birder or ornithologist worth their salt is going to call you out for saying seagull instead of gull. (If they do, they will bring it up benignly.) Gulls as a label in itself is taxonomically ambiguous, pertaining to several genera within the Laridae family while excluding terns, skimmers and noddies. Instead of splitting feathers over vernacular, try learning about local gulls in your neighbourhood (if you have any.) Download an app like Merlin or Audubon for quick reference if you stumble upon an interesting bird. Your local gull species may not have the vocal acumen of a Song Sparrow Melospiza melodia, nor the fantastically coloured plumage of a Wood Duck Aix Sponsa. For me at least, I find tremendous enjoyment in watching a second winter Olympic Gull walk past me, a collage of grey and brown and white; or seeing a first winter individual staring at me with those deep and dusky eyes, its first grey scapulars developing, like ash on a dirt road. Gulls are full of personality. I observe them trying to snatch fish from cormorants; pulling up worms from park grass; standing on volleyball pegs and tidal rocks, heads tucked in behind their backs and bodies rotating side to side as if to lull themselves asleep. Even the seemingly normal, mundane, sometimes irritating aspects of life can offer up wonders if you are patient. Gulls or otherwise.

References:

“I Was Mugged by a Gang of Seagulls – Granville Island, Vancouver Traveller Reviews – Tripadvisor.” Tripadvisor, 2011, www.tripadvisor.ca/ShowUserReviews-g154943-d156255-r120159573-GranvilleIsland-VancouverBritish_Columbia.html.

Edward Kroc. “Reproductive Ecology of Urban-Nesting Glaucous-Winged Gulls Larus glaucescens in Vancouver, BC, Canada.” Marine Ornithology, vol. 46, 2018, pp. 155–16.

Louise K. Blight, Douglas F. Bertram, Edward Kroc. “Evaluating UAV-based techniques to census an urban-nesting gull population on Canada’s Pacific coast.” Journal of Unmanned Vehicle Systems, vol. 7(4), 2019, pp. 312-324. https://doi.org/10.1139/juvs-2019-0005

Steve N.G. Howel, Jon Dunn. “Peterson Reference Guides to Gulls of the Americas.” Houghton Mifflin Harcourt, 2007, p. 25.

Birds of the World, https://birdsoftheworld.org/bow

[blauesonnenblume]

Olrog’s gull (L. atlanticus)

Kelp’s gull (L. dominicanus) (oui ils se ressemblent)

Dolphin gull (Leucophaeus scoresbii) (trop mimi tout rouge! pigeon des mers)

Royal tern (Thalasseus maxima)

Magallenic penguin (Spheniscus magellanicus) (bb)

Blue-eyed cormorant (Phalacrocorax atriceps)

Neotropic cormorant (P. brasilianus)

Rock shag (L. magellanicus)

[birdstudies]

September 21, 2019 - Belcher's Gull (Larus belcheri)

Previously classified with the Olrog’s Gull as a single species, known as the Band-tailed Gull, these birds are found along the coasts of Peru and Chile. They feed primarily on aquatic animals, including fish, crabs, and shellfish, as well as carrion and the eggs of other seabirds. Breeding in colonies, their nests are depressions in the ground lined with moss, grasses, leaves, and other plant materials. Both parents incubate the eggs and feed the chicks.

[dendroica]

Olrog's Gull (Larus atlanticus)

The Olrog’s Gull is a threatened endemic species of the Atlantic coast of Argentina. It has a restricted breeding distributional range, small total population size and a rather specialized feeding ecology, consuming mostly crabs during the breeding season. In winter, part of the population may disperse north, reaching Uruguay and Brazil.

(via Neotropical Birds)

[bestgullpoll]

Round 1, Side A: Match 9

[Image ID: Two pictures of gulls. The left is an Olrog's gull standing in shallow water. The right is a slender-billed gull standing on sand. /End ID]

The Olrog's gull (Larus atlanticus) is a large gull that lives along the Atlantic coast of southern Brazil, Uruguay, and Argentina. They typically measure 50-60 cm (20-24 in) in length and 130-140 cm (51-55 in) in wingspan. They have white underparts and head, black back and wings, yellow legs, yellow bill with red and black tip, and white tail with black band. They eat crabs, giving them the name gaviota cangrejera or "crab-eater gull" in their native range, as well as molluscs, fish, and insects. They are listed as near threatened by the IUCN.

The slender-billed gull (Chroicocephalus genei) is a mid-sized gull that breeds around the Mediterranean and northwestern Indian Ocean. They typically measure 37-40 cm (15-16 in) in length and 90-102 cm (35-40 in) in wingspan. They have pale grey upperparts, dark red legs and bill, and white head. Their white underparts frequently show a rosy pink flush. Their pale grey wings are black at the tips with a white leading edge. They have a long-necked appearance. They feed on fish, as well as marine invertebrates and insects.

Olrog's gull image by Cláudio D Timm

slender-billed gull by Dhaval Vargiya

[bestgullpoll]

Best Gull Poll: Round 1, Side A

The gull games have begun! Find the individual poll posts for this batch of matchups linked below. They will run for 24 hours, until May 5, 2023 at 00:00 UTC.

Match 1: kelp gull vs Andean gull

Match 2: lava gull vs black-tailed gull

Match 3: Pacific gull vs Franklin's gull

Match 4: Belcher's gull vs Saunders's gull

Match 5: western gull vs great black-backed gull

Match 6: Armenian gull vs black-headed gull

Match 7: glaucous gull vs yellow-legged gull

Match 8: Audouin's gull vs Sabine's gull

Match 9: Olrog's gull vs slender-billed gull

Match 10: Mediterranean gull vs lesser black-backed gull

Match 11: Iceland gull vs brown-headed gull

[bestgullpoll]

Best Gull Poll: Round 2, Side A

Time for Round 2! Watch out - there's some new competitors in this round! This set of matchups will run for 24 hours, until May 10, 2023 00:00 UTC.

Match 22: relict gull vs Andean gull

Match 23: lava gull vs Franklin's gull

Match 24: black-billed gull vs Saunders's gull

Match 25: Vega gull vs great black-backed gull

Match 26: little gull vs black-headed gull

Match 27: glaucous gull vs Sabine's gull

Match 28: Heermann's gull vs Olrog's gull

Match 29: Mediterranean gull vs brown-headed gull