Tuesday, December 24, 2019

Avian Dinosaurs: Bald Eagles at the Sacramento National Wildlife Refuge

Sometimes I am reminded that the dinosaurs never actually went extinct. They were decimated certainly, and their present-day species don't look all that much like their ancient ancestors, but there are occasional clues to their dinosaurian past. The claws of a Bald Eagle (Haliaeetus leucocephalus), for instance. We were at the Sacramento National Wildlife Refuge just before Christmas, and saw several of birds at close quarters.
How close are the birds to the dinosaurs? Dinosaurs are classed as reptiles, but the reptiles we know today, the lizards, snakes, turtles, and crocodiles, were separate evolutionary lines in the Permian and early Triassic, before the dinosaurs even arose. The crocodilians are the closest of these ancient relatives, but they were already on their own evolutionary path during the Jurassic and Cretaceous periods when the dinosaurs were dominating the terrestrial habitats of the planet.
The birds on the other hand developed from the dinosaurs, descending from small theropod carnivores similar to the Velociraptor or Deinonychus, monsters made famous in the Jurassic Park movies. Evidence has emerged in recent decades that many dinosaurs may have in fact sported feathers (which are modified scales). Many bird embryos support teeth that are later resorbed during development.
In any case, that's what I was thinking about as we came across at least three Bald Eagles while traveling the auto tour route at the Sacramento Refuge. There were a couple of immature individuals and one adult. They were accustomed to automobiles passing by so they didn't retreat as we passed by, enabling me to get a zoomed view of their claws.
One juvenile was still hanging out with mom, while the other was on its own. They were a sight to see in the rain (that's why they all looked a little scruffy; they were generally soaked).

Sunday, December 15, 2019

The Wonderful Woodpeckers of the Tuolumne River

One of the constant joys of birdwatching along the Tuolumne River along the Parkway Trail is the variety of woodpeckers who are almost ever-present along the walkway. Eight species of woodpecker have been reported in Stanislaus County. I see three of them on a constant basis, and I've seen two more species on rare occasions. The three I have yet to see are the Yellow-bellied Sapsucker (very rare in our area), the Lewis's Woodpecker, and the Hairy Woodpecker.
Often the first one I will see or hear will be the Acorn Woodpecker (Melanerpes formicivorus). A small colony of three or four of them live in a dead cottonwood tree near the west end of the trail. I often hear their distinctive call before I see them. They are usually busy hiding their precious acorns in the tree trunks, and spend a lot of time guarding their stores. Their faces make me think of clowns.
I often hear a chirp - chirp - chrrrchrrrrchrrrrr in the trees above the trail, high in the oak trees. It is a Nuttall's Woodpecker (Picoides nuttallii) which is about as close to being a California endemic species as a bird can be. They range just into the northern part of Baja, along with all of four sightings in Nevada, and a single sighting in Oregon. Although they are strongly associated with oak trees, they don't consume acorns. They are more interested in gleaning bugs from the furrows in the trunks of the trees.
The third of the common woodpeckers on the Tuolumne River is the Northern Flicker (Colaptes auratus). They look less like "normal" woodpeckers, and behave differently in many ways as well. For one, they spend much of their time foraging for ants and beetles on the ground. I almost always hear their piercing call before I see them.
The "rare" woodpeckers, the ones I only see occasionally, include the Downy Woodpecker (Picoides pubescents), and the Red-breasted Sapsucker (Sphyrapicus ruber). I've only seen the Downy Woodpecker a half-dozen times in the past two years, and the Sapsucker only once, back in October. Across the entire county, there have only been a dozen or so reports of the Red-breasted Sapsucker this year (and none at all of the Yellow-breasted variety).

The sighting of Downy Woodpecker this morning was what got me thinking about how often I see woodpeckers along the Tuolumne Parkway Trail. I didn't get a clear picture this time, but I've included a picture from a few years ago. The Downy (and similar Hairy) Woodpeckers are similar to the Nuttall's Woodpecker overall, but the Nuttall's have bars across their back while the others have a vertical white band.

We've seen 116 species of birds on the Tuolumne trail this year. If you are patient (and willing the climb the stairway), it's a great place to practice your birdwatching skills.

A Well-Hidden White-Breasted Nuthatch on the Tuolumne River

One of the most elusive of the birds I search for on the Tuolumne River. It's not that they are rare. They're found throughout our county on a regular basis. And many savvy birders hear them before they find them, because they can be noisemakers. But I never seem to spy them on my daily walks, even though I know they are there, up in the big oaks along the river. It was June before I saw my first one of the year, and until today I hadn't seen one since September.
I've been running across all kinds of interesting birds over the last week or two, with three species reported for the first time ever (three kinds of ducks passing through the area), and a very rare winter visitor, a pair of Hooded Orioles. Today was a nice surprise, as I heard an unfamiliar ruckus in the oak tree. After a few minutes, I spotted the White-breasted Nuthatch (Sitta carolinesis) working its way down the trunk of the oak tree.

Now if I could just find that elusive Red-breasted Nuthatch!

Wednesday, December 11, 2019

At Least He Isn't Lonely...A Second Hooded Oriole This Winter on the Tuolumne River!

The other day I posted about what I thought must be the loneliest bird in all of California. There was a male Hooded Oriole (Icterus cucullatus) hanging out near the oriole nesting site on the bluffs above the Tuolumne River, and they are not supposed to be here in the state right now. Literally all of them migrated to Mexico and Central America many weeks ago, and there have been no sightings of any in the state in the last month except for three birds in the far south part around San Diego.

So I was on my walk today and of course I was watching out for the Oriole and much to my surprise, there it was. Except something was different...it didn't have the prominent black chin patch that distinguishes the mature males. The one last week did. I can now say there are TWO Hooded Orioles in Central California, and they are probably hanging out with each other (the site was only a few yards from where I saw the other one last week). This one is either a female, or an immature male. I don't know why they are still here, but I've developed a complicated hypothesis...

I've been seeing all the "traditional" Christmas movies this week, "National Lampoon's Christmas Vacation", "Elf", "Home Alone", "Die Hard", and so on, including the great classic (biting my tongue as I say that) "Christmas with the Kranks". If you aren't familiar with the premise, the Kranks were going to have their first Christmas without their daughter (who was in Peru), so they decided to skip Christmas and take a cruise in the tropics. Their daughter decided to come home, and hilarity ensued (sort of).

Regarding these two Hooded Orioles, I see kind of an opposite situation. I imagine I heard this conversation between them...

"Look, EVERYONE is migrating to the tropics for Christmas. They ALWAYS do, and it's a long way, and hard and dangerous. I think we should just stay put and skip Christmas this year."

"I don't know, Luther. There must be a reason everyone goes. But okay, if you think it's a good idea"

Four weeks later...thirty degrees and foggy outside.

"Luther, if you ever have a feather-brained idea like this again, keep it to yourself..."

Does anyone have a better idea?

Wednesday, December 4, 2019

The Bird That Shouldn't Be There: Hooded Oriole on the Tuolumne River

Today's walk along the Tuolumne River was extraordinary. I got there just as the latest storm ended, so there were no people on the trail, but lots of birds were enjoying the respite from all the hikers and exercisers. I counted 29 species, including one bird seen for the first time on this stretch of the river, a Bufflehead. There were also some that I haven't seen in a long time, including the first winter arrival of the Common Goldeneye, a flock of Northern Shovelers, and a Green Heron. It was actually kind of astounding.

But nothing surprised me more than the bird I saw on the top of the bluff at the east end of the water treatment plant. At first, I only saw the shape, and I thought it might be a mere Mockingbird, but something about it made me flip on the camera and take a closer look. I saw the bright yellow breast, the black chin, and my jaw dropped. It was a Hooded Oriole!

To understand just how odd this is, is to realize that the Hooded Oriole (Icterus cucullatus) is a bird of the tropics, and we are at the northern end of its range here in the Central Valley of California...in the SUMMER. They all migrate to Mexico and Central America for the winter. Literally all of them. There have been just three sightings of Hooded Orioles in California in the last 30 days, and all three were in southern California.

I don't know the story of this particular bird. It was hanging out just a few hundred feet from the palm trees where some Orioles nested last spring, so this could be one of the individuals that I photographed many times last summer. Maybe it was injured in some way and wasn't able to join the migration. Or maybe it just missed the bus. But in any case, I saw a bird today that shouldn't be there. Which explains the poor quality of the picture: I barely had time to focus before it flew away.

Sunday, December 1, 2019

Red-Necked Grebe in the Siuslaw River Estuary at Florence, Oregon

Thanksgiving is not one of the times that I expect to see a great many birds. I'm usually traveling through the Cascades and Siskiyou Mountains in winter-like conditions, and this year was no exception. But then I arrive at my destination on the Oregon coast at Florence, and I have better luck. Florence lies along the estuary of the Siuslaw River. A lot of birds winter in the region where temperatures are more mild. The waters of the Pacific moderate the local conditions.
I saw some interesting birds over the holidays, but the last night I was watching the gulls and Buffleheads near the marina when I saw I different bird. I got pictures and realized I had come across a new bird for me, a Red-necked Grebe (Podiceps grisegena). It's a bird I have little chance of ever seeing back home. The last time anyone saw one in my county was in 2008.
Red-necked Grebes breed far to the north in the Arctic, but spend winters along the coast as far south as the LA/San Diego coast. They eat fish, amphibians, and invertebrates.

The Siuslaw River rises in the Coast Ranges of Oregon and flows 110 miles to the sea. The river is not particularly large, but it has a huge estuary that is influenced by the tides as far upstream as 26 miles. The lower river has miles of wetlands that provide critical habitat for birds and other wildlife. It is one of few Oregon rivers that is undammed, but logging has had a huge effect on the health of the river.