When I started this Dawn Chorus I was focusing on some of my favorite summer migrants, the grosbeaks. However I also want to pay tribute to our dear friend and loyal Choruster martyc35, who died a week ago. So this Dawn Chorus has two parts.
Part 1 GROSBEAKS
Days are shortening in the Pacific Northwest and my favorite summer migrants are flowing southward. Some have gone already (like Rufous hummers, Olive-sided Flycatchers, Swainson’s thrushes), some are still gathering themselves (like all the swallows) and some are just about to depart, like the grosbeaks.
In the lowland Western United States we have two kinds of grosbeaks: Black-headed and Evening. They both appear in spring. The former migrate here from Mexico, the latter from who knows where? Range maps show them as here year-round but they must wander freely.
I make a point of reporting my First of Year sightings of them on eBird. I never understood why these two grosbeaks are in completely different sections of the eBird list (and my field guides) until I did a little reading. Turns out “Grosbeak” simply means “fat beak” from the French grosbec, coined in the 17th century. That strong fat beak is well suited for cracking open hard seeds.
However not all fat-beaked birds are grosbeaks, nor are all grosbeaks especially fat-beaked (like the Pine Grosbeak). The term is just loosely descriptive, not taxonomic, meaning grosbeaks aren’t necessarily very closely related, the way swallows or woodpeckers or flycatchers are. Modern DNA analysis has grouped all these birds according to their evolutionary relationships, so now the term grosbeak is just an artifact of the era when animals were named by their looks.
Another oddity: that distinctive fat beak doesn’t mean these birds focus on big hard seeds. Much of their diet is caterpillars, insects, berries. There are plenty of berries ripening in the woods around here right now, like salal, which are great for packing in calories for migration. But when there is a hard nut to crack, grosbeaks can exert a lot of crushing force.
There are two different bird families that contain grosbeaks. In the United States, our grosbeaks are either —
in the Cardinal family (Cardinalidae):
- Black-headed grosbeak
- Rose-breasted grosbeak
- Blue grosbeak
(Cardinal family fat-beaked birds that AREN’T grosbeaks? Cardinals, Pyrrhuloxia, and Painted Buntings)
or the Finch family (Fringillidae):
- Evening grosbeak
- Pine grosbeak
Did you know?
—> The Rose-breasted and Black-headed are east/west ecological equivalents, but the Blue grosbeak is more closely related to buntings.
—> Black-headed (and Rose-breasted) Grosbeak diet is not primarily big seeds. Throughout most of the year, over half of their diet is made up of insects. Their huge beaks allows them to eat large grasshoppers, crickets and other insects that have tough exoskeletons, as well as snails.
—> By singing a "male" song, the female Black-headed Grosbeak can trick her mate into thinking a rival male is nearby, forcing him to stay closer to the nest.
—> Black-headed Grosbeak is one of the few birds than can eat monarch butterflies, despite the noxious chemicals that the monarchs accumulate from their milkweed diet. Black-headed Grosbeaks eat many monarchs on their wintering grounds.
(thousandoaks.wbu.com/… Wild Birds Unlimited)
Grosbeaks go through a lot of molts, so I’m lost when it comes to telling who is who aside from the adult male. In spring when they arrive, it’s pretty clear which are adult females, and in summer the begging birds are juveniles. Other than those, I’d really need to get some close looks and do some reading to differentiate females from juveniles of both gender.
Black-headed grosbeaks are abundant and reliable breeders where I live. There’s a variety of conifer and deciduous trees in my neighborhood, plus they enjoy my birdfeeder and birdbaths.
According to the Breeding Bird Survey, the population of Black-headed Grosbeaks in Washington has increased significantly since 1966. They benefit from some human activity on the breeding grounds. Suburban development and logging generally increase the amount of broadleaved vegetation in the coniferous-dominated Pacific Northwest, and the increasing numbers of orchards in eastern Washington has provided more habitat as well. Development creates habitat to some extent, but increasing urbanization reduces available habitat. Black-headed Grosbeaks are not found in typical suburbs, but in more outlying areas that are still semi-rural. These birds need a certain density of big deciduous trees. ww.birdweb.org/...
They arrive in May and I hear their singing for the next couple of months before the juvenile wailing starts in July. By the end of August they’ll all be gone. Already I’m hearing fewer and fewer juvs begging. The BH grosbeak song sounds a lot like a Robin’s but more lively and melodic.
The juvenile wail is pretty distinctive too, different from the Crossbills and other finches that are also around right now. Macaulay has audio clips of it but I can’t embed them. Here’s one:
This YouTube video is labeled “practicing adult song” but it sound very much like what I’m hearing outside right now as the fledgling BH grosbeaks beg:
These stunning birds are much less common around my place than the Black-headed grosbeaks. Some years I don’t see them at all. When they do appear, it’s in late spring, and if they nest nearby I’ll see fledglings in summer. Evening grosbeaks are irruptive throughout the year, following food supplies. I never see them in winter, which is too bad since that’s when they flock in large numbers, I understand.
Evening grosbeaks eat many kinds of insects and larvae as well as a wide variety of seeds.
Did you know?
—> Evening Grosbeaks like to eat wild cherries, but unlike other birds, they only eat the pits. After removing the fleshy fruit, they crush the slippery seeds with special pads in their “gross beak.”
—> So favored are cherry pits that Evening Grosbeaks sometimes seek out the pits voided by American Robins.
—> The Evening Grosbeak was named in 1825 based on erroneous accounts that they became vocal and active only “at the approach of night.” This erroneous belief persisted for years, and the name is still a misnomer. How Did the Evening Grosbeak Get Its Misleading Name? William Cooper, an ornithologist at the Lyceum of Natural History of New York got wrong information from a friend about its behavior and used that to name the Evening Grosbeak (in fact they sing throughout the day, not in the evening). John K. Townsend, an early naturalist in the Pacific Northwest, debunked that description in 1836 in a letter to JJ Audubon but by then the name had stuck.
—> Evening Grosbeaks seem to delight in snipping off the twigs of Sugar Maple trees and sipping the sweet sap.
sacramento.wbu.com/...Wild Birds Unlimited
Evening grosbeaks used to be a Western bird, but they’ve spread east:
Evening Grosbeaks were formerly restricted to the western United States but have expanded their range eastward across the country. This expansion is credited to the planting of box elders and other seed- and fruit-bearing trees across the northern prairies, as well as the presence of bird feeders. As is the case with many irruptive, nomadic species, it is difficult to determine the true population of Evening Grosbeaks. For example, considerable variation in the numbers wintering in the Washington lowlands may reflect either changes in population or merely varying migration.
The other grosbeaks that occur in the U.S. are found in the East, the South and the North. Brief “snapshots” are below; I hope Dawn Chorusters in their ranges can add personal experience with them and other photos.
In the east: Rose-breasted Grosbeak
range: From the Rocky Mts eastward. In the US, summer breeding migrant or seen in migration
diet: During breeding season, eat a lot of insects, as well as wild fruit and seeds. Fall migration and on their wintering grounds eat various invertebrates and plant material.
In the south: the Blue Grosbeak
range: summer migrant, in southern U.S. only
diet: feed mostly on insects (especially grasshoppers and crickets), also eat other invertebrates such as snails, along with the seeds of wild and cultivated grains
In the north and mountains: the Pine Grosbeak
range: northern boreal forests of Canada, Asia and high elevations
diet: Nearly 100% of their diet is made up of buds, seeds, and fruits from spruce, pine, juniper, birch, mountain ash, maple, box elder, crabapple, blackberry, ragweed, and burdock.
Part 2 FAREWELL to martyc35
Our good friend Marty was a tough old lady but at 87, after a series of hospitalizations for major organ failure this past year, she made the decision to halt dialysis and die at home peacefully in home hospice care. Marty was a regular cheerful presence at the Dawn Chorus, expressing support and appreciation for everyone’s bird observations. More about Marty’s life here: The Daily Bucket - martyc35 has flown.
Marty loved all birds but she had a special fondness for Osprey. Beautiful, fierce, fabulous fishers — osprey have intensity of spirit even we humans can feel, just watching them. Like grosbeaks, osprey are summer migrants, and will depart when their bebes are ready to make the journey down south.
There are no osprey nests on the island where I live (that I know of) but a pair nested annually on a light fixture in Anacortes that remained from an old industrial site by the shore. I used to stop whenever we went over to the mainland to see the nesting progress. A development company bought up the site several decades ago, and last year began clearing it for new construction. Their plans included tearing down the osprey nest, to the sorrow of locals. Imagine my delight when I learned they’d set up a pole earlier this year on the edge of the site with a starter nest. And that the pair (probably the same birds) adopted it this spring. The last time I was on the mainland, July 27, I checked it out. Bonus: I can get much closer to this one! There were two nestlings, pretty far along. Osprey fledge in August around here.
Marty would have been tickled by how their story has turned out.
Some pics of the nest a couple weeks ago:
What’s your birdy news of the week?