Birds of the Bay: Heermann’s Gull
by Bob Shanman
So, two friends were walking along the beach in Hermosa when a large flock of gulls suddenly lifted off the sand and flew right in front of them. “Darn seagulls,” said one friend. The other friend, a birder, corrected him. “Those are not seagulls” he said. “We are on Santa Monica Bay, so it’s obvious that they are baygulls. And if they land on the water, they are water baygulls.”
“Sure” responded the first friend. “Like in saltwater baygulls!”
That’s enough bad humor for one column. Google “gull jokes” for more.
An adult Heermann’s Gull, distinguished by its white head, red beak and black legs, soars over El Porto on to its winter breeding ground in Baja California. Photo by Dave Weldon (Photoshooter.org)
“Seagull” or “sea gull” is a colloquial term for a family of birds ornithologists and birders refer to as “gulls.” Gulls are in the bird family Laridae, from the Greek word “Laru,” meaning ravenous sea bird. What an apt name for these annoying marauders. There are many names for a group of gulls, but most often they are called a flock or colony. Other names are scavenging, a squabble and a screech.
Gulls are found worldwide and are most common along coasts and nearshore waters. Many species do spend time at sea, hence the name. But they are also found far from the oceans, often breeding along the shores of inland lakes and seas. Locally, they typically gather in flocks along South Bay beaches. They eat anything, are excellent scavengers (large flocks can be found near most landfills), and force other birds to give up food they have caught (parasitism). Some gulls are even kleptoparasitic, meaning they will steal food right out of another bird’s beak or pouch, including a pelican’s pouch. As you learn about the gulls, look through the groups on the beach and you will see birds of similar appearance do flock together. Even within mixed groups, birds of the same species tend to congregate with their own.
Around the world, there are about 51 species of gulls. In California, 24 species have been seen over time, and in Los Angeles County, 20 species have been documented, many in the South Bay. Gulls generally breed with their own kind, but interbreeding (hybridization) is common. While this adds to the challenge of identification, it also adds fun to the conversations among birders that take place wherever gulls are found.
Along the local beaches, from fall to mid-spring is the best time to hone up on gull identification skills. The most readily seen species are the Western, California, Ring-billed and Heermann’s gulls. They each have readily identifiable markings. Start with these four, and you will wow your friends with your newfound knowledge and trivia. Most gulls will be gone by late spring, but there are always some who don’t get the memo and hang around all year.
As I write this, it is January 7, so it’s time to get to this month’s birds before they head off for their spring migration. As you stroll along the beach, notice that most gulls are white-headed, white bodied with wings and back (mantle) of varying shades of gray. Many young birds will have mottled plumage (more about them next month). Most have yellowish bills with different markings. Leg color varies from pink or yellow or greenish, except for one. This bird has a white head, and a blood-red bill with a dark tip, a medium gray chest, dark gray wings, and mantle, and black legs. This is the adult Heermann’s Gull, and it is one of the loveliest of all the gulls. Ariving on the South Bay beaches in early August, they are easily recognized by their chocolate brown plumage and black legs and beak.
The reason to hurry out to see them is they are ready to migrate. They are the earliest of the gulls to leave for their breeding grounds. Most adults will be gone by the end of January heading south to their primary breeding area in Baja California. It is one of very few birds that has this reverse migration (heading south in the spring and north in the fall) for breeding.
Heermann’s Gulls are west-coast birds (there have been rare sightings east of the coastal states). They breed on rocky islands off the coast of Baja. There are also several small breeding colonies in California. The world population is about 350,000 birds, and it is estimated that up to 95 percent breed on Isla Rasa off Baja. The breeding season is from March to June. The typical clutch size is 1 to 2 eggs. Both parents brood the eggs and feed the chicks. The young hatch after about four weeks and leave the nest (fledging) after an additional 45 days. By mid-May, most of the young have fledged, and the parents start their northward fall migration heading as far as British Columbia. The first fall migrants (juveniles and failed nesters) begin arriving on local beaches in early June. Fall migration for adults is essentially over by late July to early August. The oldest known breeding Heermann’s Gull was 28 years, based on leg band data.
The recently fledged birds stay on the nesting grounds to fatten up for their first migration. Arriving on South Bay beaches in early August, they are easily recognized by their chocolate brown plumage and black legs and beak. By late fall, their bill is two-toned, pale at the base and dark at the tip. By January, they are molting into their first-year plumage, showing hints of gray. Each year their appearance changes as they go through the annual molt, looking more like adult birds with time. By the end of their third winter here (approaching 3 years old), they are in their first adult winter plumage, with gray flecking in the head, and usually with some black in the otherwise all-red beak. All adults will have the gray flecking the head plumage in winter.
Upon arriving on South Bay beaches in early August, young Heermann’s Gulls are easily recognized by their chocolate brown plumage and black legs and beak. Photo by Bob Shanman
The Heermann’s Gull is one of easier gulls to identify, given its unique coloration and markings. Starting with the beak and feet, it is unlike the other gulls on the local beaches. When looking at any gull, start with the size of the bird, the beak color, shape and markings, and the leg color. Pretty soon, you will be sorting out the three other gulls mentioned above. Have fun, and more about gulls in next month’s column.
Good birding and be safe along the beaches.
Bob Shanman recently retired, after 28 years as owner of Wild Birds Unlimited in the South Bay. He has been an avid birder since 1977. Information in this article comes primarily from “Birds of the World” [birdsoftheworld.org], a subscription/membership service of the Laboratory of Ornithology, Cornell University, unless noted otherwise.) ER