Spring has arrived in Northern California, despite long periods of recent heavy rain. Trees are blooming, birds are singing, its green everywhere you look — truly a wonderful time to be outdoors.
Taking a lesson from the Oroville dam almost-catastrophe, water levels in the Vasona reservoir south of San Jose, CA, have been lowered substantially prior to the next series of storms expected this weekend.
Apparently, fish stranded in some of the back channels of the reservoir became fodder for the local bird life. Turkey Vultures, seagulls, crows, and even a rarely seen Bald Eagle have been spotted feeding on the fish carcasses the past couple of days.
A “venue of Vultures” (I.e., a group of them) were still present picking over the last remains of a few fish this morning.
The weather wasn’t chilly, but when the sun emerged from behind some low clouds, the Vultures immediately began basking, backs to the sun and spreading their wings wide. First one, then another and another…
I have been reading about all the rain falling over most of California, but now I’m seeing the effects first hand. We re-visited our favorite winery in Sonoma this past weekend and found Lake Sonoma overflowing into various tributaries.
However, the flooding here is minuscule compared to the amount of water pouring over the Oroville dam in the foothills of the western slope of the Sierra Nevada mountains.
Thousands of (almost 200,000) homes downstream have been evacuated, but more hard rain is expected next weekend for this rain-soaked and flooded area. From extreme drought to extreme flood, weather fit for neither man nor beast.
UPDATE: water leaving the dam via the emergency spillway was producing too much erosion with the potential for collapse of that wall of the dam. Instead, engineers increased the flow out the concrete spillway today. Great video of the process on Vox: http://www.vox.com/science-and-health/2017/2/13/14598042/oroville-dam-flood-evacuation
My response to the name of this unusual bird, the Common Pauraque (“pa-rock’-hay”) was “pa-what?”. The Common Parauque is a type of Nightjar, like the Common Nighthawks we see and hear on summer evenings in most of the U.S. It’s another of those rare visitors to the U.S., found only in the Rio Grande Valley near the Mexican border, but they are common throughout Central and South America.
Like other members of its family, these birds are active primarily at dusk and dawn, flying over vegetation or along hiking trails, or even perching near where nocturnal insects forage in order to grab them up in their over-sized mouth. In the daytime, they roost on open ground, but their highly camouflaged plumage makes them really hard to detect.
How would it catch insects with that tiny little nubbin of a bill?
With its enormous gape, of course.
Here’s another bird that just barely makes it into the U.S., where it resides in the Rio Grand river valley in South Texas — the Chachalaca. They are related to chickens and turkeys, and sort of resemble them in looks and habits, but Chachalacas, and their close cousins the Guans, and Currasows, make up their own tropically distributed family, the Cracidae.
You almost never see just one Chachalaca — they are highly social, and quite happy foraging either on the ground or in trees.
Highly social birds are often highly vocal, and Chachalacas are no exception. Click on the video to hear a sample of their cackling conversation.
I’m still working through the thousands of images from the 3-day bird photography workshop I attended in Alamo, Texas a couple of weeks ago, and found this series of interactions between a Golden-fronted Woodpecker and a Red-winged Blackbird. No one can say those blackbirds aren’t feisty, pesky, and challenging.
Early one evening just as the sun was setting, we spied a large flock of Long-billed Dowitchers resting on the shore of a large inland lake in Laguna Vista, Texas.
A photographer can only creep up so far on these birds before they take flight, swarming around in a huge circle, checking out the dangers below them, before settling back on the shore again.
The striking thing about whole-flock flights like this is that huge numbers of individuals seem to swarm with organized intent, moving uniformly in the same direction as they whirl, change altitude and direction, and eventually land again. This phenomenon has been well-studied in several species of birds and is most often associated with predator detection and avoidance. How do birds do it?
To make flock flight work, each bird pays attention to 6-7 of its neighbors, following their movements closely, and making quick adjustments when a neighbor changes direction. This type of mass movement has been likened to performing “the wave” in the stands at a football match, but may be happening much more quickly than that.
Murmurations of Starlings have stunned observers and impressed many a videographer, as flocks of hundreds of thousands of birds form ever-changing patterns prior to descending into their nocturnal roosts in urban locations. The video below illustrates this well, as a peregrine falcon hunts for its evening meal within an enormous flock of Starlings in Rome. (John Downer Productions)
I tried out a new telephoto lens (Tamron 150-600 mm) at the Alan Murphy bird photography workshop in Alamo, Texas, and was very pleased with the results. It’s extremely sharp, even at full 600 mm extension, especially when the camera-lens setup is secured on a tripod. However, when zoomed all the way out, there is not much area in the frame, and it’s more likely that parts or all of the subjects will be missing from the image. But I took a chance that at least some of the images might capture the action, and indeed there were a few notable ones.
I certainly learned a lot over the course of the three days that we photographed these birds in action, and one thing that will stick with me is to take chances by zooming all the way in to get really good close-up images.
Taking a rapid series (10 frames per second) of high-shutter speed (1/5000 sec) images of flying birds allows one to see just how birds manage some of their aerial dynamics, like how to land gracefully on a small spot. The test for the birds was to flap-glide-brake from bushes about 25 feet away to land precisely on the edge of a stump feeder filled with delicious suet.
What amazed me was that all five species we observed used the same technique: flap, fold wings in horizontal posture, making them look like a speeding bullet, then brake by spreading wings wide with huge gaps between the flared primary feathers and switching to a vertical posture with outstretched feet. This is the type of flight used by many small to medium-sized songbirds, often viewed as roller coaster, or bounding flight.
Bounding flight like this accomplishes at least two important things: first, it saves energy, 15-20% over the cost of continuous flapping because of the reduced drag during the glide (closed wing) phase; second, it lowers the cost of flying more slowly between closely spaced perches.
Not every approach to the stump was completely graceful, but birds are such adroit athletes, even being slightly off-balance on approach can be immediately corrected.