Banded Brant at Dungeness Bay - Photo: Bob Boekelheide
The Story of Brant
by Bob Boekelheide
February 2021
Late winter is a critical time during the annual cycles of many birds. After surviving difficult conditions through a long winter, at some point birds must transition over to their need to prepare for the next nesting season. As winter turns to spring, they must fatten up for migration and undergo physiological changes that kick-start their bodies for reproduction.
It turns out that March and April are the peak time of year when we see Brant in coastal waters along the Strait of Juan de Fuca. We of course have Brant here throughout the winter, such as those we tally on the Sequim-Dungeness Christmas Bird Count (Figure 1), but their numbers swell in March and April as more arrive from wintering areas further south.
Picture the annual cycle of Brant in western North America. The great majority of the West Coast population nests at the Yukon-Kuskokwim Delta in western Alaska, along with some on the North Slope of Alaska and even a few that nest way up in the Canadian Archipeligo as far as Prince Patrick Island. Prince Patrick Island is way up there. After their chicks leave the nest and grow stronger, adult Brant undergo a complete molt, in which they become flightless for a few weeks as they drop their old flight feathers and grow new ones. After molting, nearly all the West Coast Brant fly to a place called Izembek Lagoon near the tip of the Alaskan Peninsula, where they eat like mad and prepare for migration to their wintering areas.
The fall migration of Brant is truly incredible. More than half of the Alaskan population flies non-stop from the Alaskan Peninsula to winter in Baja California, at places like San Ignacio Lagoon. Brant have been reported covering this 3000-mi distance in as little as 55-60 hours, which means they fly an average of about 50 to 60 mph straight for almost three days. But some Brant do not fly all the way to Mexico. Some fly shorter distances to other locations on the West Coast, to places like Humboldt Bay and here in the Salish Sea. Apparently there is trend for some Brant to not leave Alaska at all, instead remaining at Izembek Lagoon all winter.
Banded Brant at Dungeness Bay - Photo: Bob Boekelheide
After surviving the winter, most Brant make shorter flights during spring migration instead of one long one, stopping several times along the Pacific Coast on their way north. One of those sites is right here at Dungeness Bay, where the sound of their chatty voices increases in late winter. They voraciously feed at these locations, trying to keep their bodies in good shape for the upcoming nesting season.
Like other geese, Brant are largely vegetarians. What makes Brant stand apart from the other geese, however, is their reliance on particular species of marine plants and algae for much of the year. Their principal food in non-breeding habitats is eelgrass (Zostera marina), along with sea lettuce (Ulva) and other algae. Maybe not coincidentally, their spring migration through the Salish Sea also coincides with the late-winter herring spawn, when herring attach their sticky eggs all over blades of eelgrass, algae, and other substrates. This means that Brant feeding at herring spawns might ingest a double dose not only of eelgrass but also of high-protein herring eggs.
Brant feeding at 3 Crabs - Photo: Bob Boekelheide
These herring spawns are a big deal. I've been lucky to witness several herring spawns in California, Washington and British Columbia, where birds and marine mammals gather by the thousands to gobble up scrumptious herring roe and the fish themselves. One of the last great herring spawns in the Salish Sea occurs on the east side of Vancouver Island in the Strait of Georgia, ranging between Comox and Nanaimo. Right there in the thick of the feeding flocks are Brant, scouring the beaches and sandbars picking up eelgrass and attached herring eggs. The Canadians even have a Brant Festival at Parksville around this time, to celebrate their spring arrival. There used to be sizeable herring spawns in Dungeness, Sequim, and Discovery Bays, but according to the WDFW they are now tiny compared to their former selves.
As part of the Three Crabs Restoration Project, between 2014 and 2018 OPAS volunteers counted Brant and other birds three times each month within a specific area at Three Crabs beach. Figure 2 shows the annual cycle of Brant tallied on these surveys, based on the average high counts of Brant for each calendar month. You can see that our highest counts occurred from February to April, timed to the window when Brant are migrating north to nesting areas. Most of the eelgrass that Brant eat at Three Crabs beach is already broken off from where it grows on the bottom of the bay, then it washes ashore in windrows on the beach. This gives the Brant a concentrated food source in shallow water right by shore.
Here on the north Olympic Peninsula people typically see Brant feeding right on shore at places like Three Crabs, Jamestown, and Ediz Hook, but in reality Brant often feed quite a ways offshore on floating eelgrass and algae. As the tides move back and forth in the Strait of Juan de Fuca, tidal fronts and convergences concentrate floating mats of algae and eelgrass, providing feeding opportunities for Brant sometimes miles offshore. Since 2016, OPAS has cooperated with WA Dept of Natural Resources and Port Townsend Marine Science Center to conduct monthly bird and mammal surveys in the Protection Island Aquatic Reserve, a 96 sq-km body of water surrounding Protection Island. Figure 3 shows the annual cycle of Brant in the PI Aquatic Reserve, based on their densities recorded during these cruises. Once again, the highest densities of Brant in the PI Aquatic Reserve occur in March and April, the exact time that Brant migrate north. On these surveys we sometimes see long lines of Brant feeding up to 10 miles offshore, gobbling up eelgrass floating at the surface.
Figure 3 also shows an interesting pattern of higher densities offshore in November, then a drop in densities during December and January. Is this real? Researchers found a similar pattern at Padilla Bay, near Anacortes, WA, where they suggested that some Brant arriving in November used Padilla Bay to refuel, then continued migrating further south for December through February. This may also occur at Dungeness, although curiously the same pattern did not appear with the data from Three Crabs. Why not? It may be because daytime tides are so high throughout November and December that Brant are less likely to be onshore at Three Crabs beach in those months.
It's not uncommon to see Brant with leg bands in Dungeness Bay. During OPAS's Three Crabs study we found several banded Brant that we reported to the USGS Bird Banding Lab (see attached certificate). The banding reports revealed that researchers banded these Brant at two primary locations, either at the Yukon-Kuskokwim Delta in western Alaska, or at the mouth of the Colville River on the North Slope. It's mind-boggling to imagine the vast territory covered by these Brant as they migrate back and forth to and from Alaska.
Like swans and other geese, nesting pairs of Brant typically stay together all year, and young Brant remain with their parents through their first winter. Adults are extremely faithful not only to their mates, but also to both nesting and wintering areas, returning year after year to the same locations. In addition, Brant are quite long-lived -- the oldest Brant on record was at least 29 years old, although it is likely that very few reach this old age. Consequently, the Brant you see feeding at Three Crabs beach have probably been there before and will return again next year. If you see a banded Brant, try to read the bands and report the information to the Bird Banding Lab.
How many Brant are there in the world? Researchers believe the entire Pacific Coast population is likely less than 200,000 birds. The population on the Atlantic side of North America may also peak out at about 200,000. The European population is probably about the same size. This means the entire world population of Brant is probably less than the human population of Seattle, WA. When you see big flocks of Brant it might seem like there are a lot of them, but there really aren't that many. This makes it even more important to give these birds lots of space while they're feeding on beaches, keeping your dogs on leash and minimizing disturbance.
Many of the interesting facts about Brant contained in this story came from Birds of the World, an on-line resource available through Cornell Lab of Ornithology. I highly recommend that all bird aficionados subscribe to Birds of the World, both for the information and to support the Lab of Ornithology.