RAy is a very special oystercatcher. RAy and I both hang out at a nearby beach and I’ve been following his doings for the past 4 years — at least those I’ve had the chance to see, since neither of us is at the beach all the time. I call him RAy because he bears a red-and-white plastic band on his left leg that reads “RA”. He also wears a more typical metal band that has much more information but those are only readable when a bird is in hand: captured or dead. Fortunately, the lettered color band was enough information for me to track down who he is. After submitting my observation to the North American Bird Banding program (more detailed account in this Daily Bucket), I eventually received an email in December 2013 from Ruth Milner, the local WDFW Wildlife Biologist who banded him:
"Thanks for photographing and reporting the Black Oystercatcher. This is a male who was banded with his mate on Iceberg Island in May 2009 as part of a winter movements study. It’s good to know he’s still around and that his red band is still readable."
Iceberg Island is an offshore rock half a mile from this beach! He’s a local. Oystercatchers in Washington don’t migrate.
Oystercatchers are monogamous over many years so it appears that sometime after the pair were banded RAy lost his mate. I was joyful to see him with a new mate later that winter and he was with her all of 2014 (and I saw them together except during the breeding season, when they never come to this beach for the duration) and into the following spring (winter 2014-15).
After the usual summer absence RAy returned to forage on the beach in the fall alone again and was solo most of that winter (2015-16). Death, divorce? No way to know. In late winter he was joined by another oystercatcher and the pair were together until the summer breeding season. They — or more accurately RAy and another oystercatcher, possibly the same mate — returned that fall (story) and were together through last spring (winter 2016-17).
Each fall I have hoped RAy might successfully breed and raise a family. It’s not easy, even on offshore rocks like Iceberg Island away from people, dogs, traffic, raccoons. When you nest on the ground, out in the open, by yourselves, predation loss to mink, otters, gulls, ravens, crows or eagles can be very high.
So it was a huge thrill this year to finally see him with a juvenile!! This was on August 23: RAy, Ms RAy, and a pale-beaked, pale-eyed youngster making their way down the beach. The parents were very alert and protective.
I’ve seen plenty of juvenile oystercatchers, but never a particular family like this so I watched with fascination as the parents fed the youngster. Oystercatchers around here eat limpets, chitons and clams mostly, either prying attached mollusks off a rock with their flat strong beak, or jamming their beak like a knife between the shells of a clam and cutting the muscles holding it closed. There’s a learning curve to these skills.
The next day I went out again at low tide, and the family was there again, this time working the bedrock for limpets. The youngster did a lot of standing around, even though limpets are easier to pull off a rock than digging up a clam.
The family strolled down the beach, crossing paths with a Lesser Yellowlegs. Almost always shorebirds of different species ignore each other. Another oystercatcher would be an interloper and get driven off.
The tides were high for a week or so and I didn’t see the oystercatchers. They are “obligate intertidal” foragers, requiring accessible safe shorelines, and have to cease hunting at high tide. I often see them sleeping at such times. Besides their limited nesting habitat it’s the other reason oystercatchers are not numerous. There are only about 10,000 Black Oystercatchers and most of them live in Alaska and British Columbia. A recent survey (2006) counted about 500 oystercatchers in the Salish Sea, which included 108 breeding pairs.
On September 8, I coasted down the hill to the beach, and seeing a couple of people walking along the beach with a dog out in front, I figured the family would be long gone. Shorebirds hate dogs, who tend to chase them for fun. But when I caught sight of big black shorebirds further along I cycled like mad to get out in front of the walkers. Throwing down my bike by the side of the road I angled onto the sand intercepting the dog and blocked his way. Fortunately he was an slow old dog, and easily distracted (sniffing my butt lol). The oystercatchers calmed down — they’d started up their distinctive pre-departure screeching call — and continued on down the beach. I stood there obviously watching and photographing, and the walkers had the kindness to veer the other way.
It was all worth it — this time there were four oystercatchers! RAy and Mom were accompanied by two juveniles!
Most of the times since then the oystercatchers have been at the beach I’ve seen the whole family there. They often split up into pairs of one adult/one juv. The parents dig up Purple Varnish Clams one after the next (there seems to be an endless supply of them!), deftly splitting them open and allowing the youngster to pull the soft clam body out. The kids are quite eager, take possession of the morsel aggressively, sometimes turning their back on mom or dad, taking the food to the water to rinse (?).
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It’s mostly peaceable amongst the family although there are times when one youngster will chase the other off. I have no way of knowing which is which.
Occasionally the parents will feed on their own, or try to. Here’s RAy hot-footing down the beach away with a clam for himself.
Sometimes the oystercatchers appear in different combinations: one parent with both kids, one parent/one kid, one parent alone, two parents/one kid. When I sent Ruth the Wildlife Biologist some photos and an update on the new family I asked her about the first configuration I saw. She said the parents will leave a youngster hidden elsewhere for a while, resting.
The intertidal zone is a rich foraging site for many birds. Some go further onto land, like killdeer and crows. Others can swim offshore too, like gulls and ducks. Most other shorebirds, like sandpipers and dunlin, migrate to take advantage of abundant seasonal food sources in a variety of habitats, but oystercatchers can only use this very narrow strip, all year long. I see them sharing the space with other birds, and it’s interesting to observe the dynamics between them.
Even master hunters like oystercatchers pause in their feeding now and then, although they come to this beach specifically to fuel up. Occasionally I’ll see them grooming or resting, but rarely sleeping.
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The kids were likely hatched in June after a month of incubation, and fledged in early August. They are proficient flyers now — I can’t tell the difference between them and the adults at a distance. Besides flying from one end of the beach to the other, I see them flying in from the direction of Iceberg Island and off that way too after a feeding session. They make quite a racket when they fly. I usually hear them before I see them.
Flying, grooming, talking and resting they have gotten good at. Feeding, not so much. It’s been months since they hatched and the parents are still doing the heavy lifting on providing food. They spend a lot of time poking around in the rocks but mostly eat what’s found by Mom and Dad. Ruth the biologist said by the end of October the youngsters will have figured out how to feed themselves and often join with other oystercatchers in flocks over the winter. In past winters I’ve seen RAy and his mate still visiting this beach by themselves rather than flocking up. I wonder if they’ll follow that pattern this winter now they have a family. I’ve read that young oystercatchers stay with their parents until the following breeding season, at which time they’ll be driven away; Ruth said that’s true of our local birds too. I have much to watch for this winter, different from the last few years since I’ve known RAy.
Winter is coming to the Salish Sea. That doesn’t mean much in terms of temperature, but it does affect when oystercatchers can forage. The highest tides are in daylight hours in winter, as compared to low tides for much of the day in summer. The beach will look more like this as fall settles in, much less intertidal to forage in. My moments to see the oystercatchers will become fewer, and the sky more often grey.
The weather has turned in the past few days here. We’re getting rain finally, it’s cooled way down and it’s quite breezy. There will still be sunny days now and then, even in winter, but I won’t be seeing the oystercatchers in bright warm sun, relishing the abundant clams and such in the broad sandy intertidal at low tide. I hope these two youngsters become skilled at feeding themselves soon. I’ll never know who they are once they become independent, but I will always know RAy, for as long as he continues to grace this beach.
Black Oystercatcher pages at:
Birdweb
US Fish and Wildlfe Service
Pacific Wildlife Federation
Note: I’ll join you in the comments a bit later after I wake up (not an early bird).
And as always, please add your birding observations for the week in the comments!