Saturday, February 27, 2016

Deformed Pine Siskin

This is our second Pine Siskin with a deformed bill. The first, seen at Davis Mountains State Park, was clearly an injury. Its upper mandible was missing.

This one, from our trip to South Llano River State Park today, is of a less obvious cause. It appears to be a growth defect with both mandibles growing too long and curved downward. When we first saw it in full profile, we had the strange sensation of being in Hawaii seeing a honey creeper. Either the lower mandible has continued to grow even longer (that is not a tongue) or the corresponding extension of the upper mandible has broken off.  The bird was feeding at the thistle seed feeder but I was not able to establish whether it was able to pull seeds through the mesh or just feed in the tray.

Brown-Crested Titmouse

While chasing the Olive Sparrow at South Llano River State Park today, we saw many Black-Crested Titmice. One, however, had a strangely colored crest. The upper half of the crest was not black but a rich chocolate color. This is not the normal hybrid pattern for Tufted x Black-crested which has a dark gray crest and a chestnut forehead. This bi-toned crest is something I have never seen or heard described. After doing an internet search, Danielle did find this post on TexBirds.

Danielle posted a similar question on TexBirds. To date, the replies have suggested that it is some alternate form of hybridization.

Chasing an Olive Sparrow

After some pictures were posted on Facebook, we decided to chase an Olive Sparrow that has been frequenting one of the bird blinds at South Llano River State Park. This bird is normally seen in South Texas, especially in the Rio Grande Valley. Here is a map of the sightings recorded on - the yellow circle is the state park. This is the furthest north that the species has been recorded and it has been seen there on multiple occasions.

We decided to do this as a day trip, leaving Georgetown a bit after 6AM and arriving just at 9AM. This park has four bird blinds. They all have well designed features for the birds to forage around but are all very frustrating for photography. The viewing huts have windows (which you can't photograph through) and no good places for setting up a camera-tripod. Complaining aside, we headed over to the Agarita Blind and settled in.

We got our first glimpse of the sparrow soon after. This type of sparrow behaves much like a Towhee, foraging on the ground in the undergrowth at the edge of the clearing. During our 6 hour vigil, we saw it a half dozen times but it never came out in the open for more than a few seconds. From the posted pictures, others had had more luck with the bird perching on one of the decorative stumps.

We did manage to get a couple of photos that show the field marks. The Olive Sparrow is a medium sized sparrow with a very low contrast body with no patterning on the back or wings. It has a light gray breast and a pale olive wash on its gray back and wings. This is the only sparrow with this olive coloration so it is a pretty distinctive marking. The head has two narrow rufous crown and eye stripes and a broken white eye ring around a red eye. All in all, it looks more like a miniature, pale Green-Tailed Towhee than it does a sparrow.

Sunday, February 21, 2016

New Nestbox Studio

As nesting season approaches, I have rebuilt my nest box with an eye toward better integration of the cameras. I also made two copies of the box, and installed one on each side of the property. One labeled "J" and one labeled "K" after the last names of the neighbors on either side of us!

As you can see, the house is still patterned off of the standard TB-1 plan from the Texas Bluebird Society that I used last year.  I have made a couple of modifications. Apart from using pine to reduce cost, I increased the roof size to 15" x 11" in order to mount a camera under the eave. Last year I had it out on a outrigger pole fastened on the roof. I am using my original Hawk Eye Nature Camera from Birdhouse Spy Cam at this location. I screwed on some stiff plastic sheets to provide rain protection for the camera. I also widened the front and back sides of the box to create an external camera bay on the left side. Finally, I added a corrugated plastic top to help reflect sunlight during the summer. This was a tip I got from the Bluebird folks.

On the inside of the house, I mounted some spare plastic-coated hardware cloth for a "ladder". Departing from the normal design plans, I cut a hole in the side of the house so that I could mount the internal camera such that it will show the nestlings from a side angle. This is the new Hawk Eye HD Nature Camera. It has a much wider field of view and twice the resolution. It also has better color saturation but that probably will not make much difference inside the house where IR light dominates.

Here is the same camera from the back side. You can see from this image that the main nest box cavity is the same size as last year. The extra width is used as a "technology bay" to allow quick access to the camera and cabling while still providing weather protection. The Plexiglas plate that you see slides down out of the way along the grooves.

A detailed view of the top of the house shows the plastic heat shield and the crisscrossed fishing line used as a House Sparrow deterrent. There are also runs on either side of the entrance and two long lengths hanging down from the front corners of the roof. This use of monofilament is another trick from the Bluebird community. I have seen this work on my own nest box last year.

Here is the full elevation view. The pole is a 10 foot length of 1" metal electrical conduit. This pole is potted into a short 100 pound concrete pier, 12" in diameter and 8" high. A short piece of 3/8" rebar which transfixes the bottom of the pole locks it in place.  I did not bury the concrete pier but simply leveled it with some patio sand, a bit like a garden umbrella stand. Using a dolly, I can easily move the assembly to relocate it as needed and it is pretty solid in the wind.

I reused the predator baffles from last year. These are formed from 8" stove piping parts and topped with heavy duty meshing. The camera cabling runs down the pole inside the baffle to the ground. There I re-purposed a length of thin garden hose, splitting it lengthwise, to create a protective "cable loom". I ran this along the ground from the nest box to the observatory where the network video recorder is installed.

The security monitor display shows the view from the four cameras with labels to remind me what I am looking at. As before, the images from the cameras are clear but have very low color saturation. I am toying with the idea of mounting a small LED light in the box on an external switch to get color images of the nestlings.

So far a couple of Carolina Wrens and Carolina Chickadees have investigated the boxes but without going in. I have also had to evict a few wasps and ants. The taller pole is making these housekeeping chores more challenging.

Saturday, February 20, 2016

Afternoon at Pedernales Falls Blind

We spent this afternoon at the bird blinds at Pedernales Falls State Park. No rarities to chase, just a relaxing time taking pictures. I logged 23 species on eBird, though nothing out of the ordinary. Northern Cardinals definitely dominated the scene with at one point 20 of them perched in the tree over the water feature.

My best images were of this pair of ladderback woodpeckers (click for more awesome feathery details)

However, the most fun was watching a Canyon Wren hunting around the big rocks and piles of wood.

Here is a slide show of some of the images we took, some are mine, some are Danielle's:

Sunday, February 14, 2016

Valentines Day Flycatcher

This morning was attempt number two to find the presumptive Hammond's Flycatcher at Dickenson's River Bottom near Lake Granger. This bird is normally restricted to pacific and mountain states with migratory paths crossing into far west Texas. There have only been a few sightings east of Midland. This individual was first recorded on Feb 5 by Colton Robbins. Since then, it has been a draw for local birders.

We first tried yesterday morning, arriving at 8:30 which was apparently not early enough. Not a wasted trip though as we saw several dozen species at what is a new location for us. This morning we got there at 7:15. Danielle had an initial spotting of the flycatcher at 7:30 but not long enough for us to get a positive identification but enough to be fairly certain it was not the Ruby-Crown Kinglet which has a similar face as shown below.

Ruby-crowned Kinglet
With the help of Bryce and Rob Hardway we relocated the bird got a more extended view at about 8:00 as it flitted from branch to branch for the next quarter hour. After that, we lost it altogether. This species is a first for us.

This bird is a small member of the Empidonax genus, all of which look very similar. Sibley's lists the primary field marks as short narrow dark bill, distinct olive vest, long primary wing projection, and short narrow notched tail. To be honest, I am taking the word of the more experienced birders as I would not be able to make a definitive call.

Hammond's Flycatcher
The day's birding at the location also netting me a very brief view of a Pileated Woodpecker flying between trees across the river. This is another rarity here.

Thursday, February 4, 2016

Dawn Alignment of Planets

For the first time in over a decade all of the bright solar system objects are visible in the sky at the same time. Even my Pebble watch is celebrating the event. With the moon approaching crescent and a forecast of clear skies, I dragged myself out at 5AM this morning in the below freezing weather to do some imaging of the planets. Earlier in the week I had scouted some sites that afforded a low southeast horizon with minimal light dome in that direction. This was to give me a better chance of imaging Mercury which is easily washed out. I chose a spot northeast of Georgetown on CR-150, about 20 minutes from home.

Since I do not have a fish-eye lens, I had to resort to creating a mosaic using my widest lens, a Canon EFS 18-55mm f/3.5-5.6 IS. I set up a tripod with a Vixen Polarie tracker to allow me to take longer exposures without star trailing so that I could keep the ISO low. I spent a half hour or so setting up, aligning the tracker and taking test shots. I used Astrophotography Tool to focus the lens and capture the images. Without using a computer, it is nearly impossible to get critical focus with this lens.

The final mosaic below consists of three frames, the first centered on the moon, the second on Spica, and the third on Regulus. I took an additional image of the eastern horizon with the tracker turned off to get the trees in focus. Each frame was taken with the Canon 7DII set at ISO-200. I decided to not create spiky stars so left the lens wide open at f/3.5. Each frame was exposed for 120 sec. The images started in the east at 6:15AM and progressed westward ending at 6:25AM. There was a fairly narrow window of time when Mercury was above the horizon muck but not yet washed out by the dawn light.

I used Photoshop to align the frames into a mosaic, performing a bit of distortion on the center image to align stars along the joins. Using adjustment layers, I tweaked the exposure, gamma, and color balance of each frame to get a smooth transition. The adjustments were especially necessary because the lighting conditions changed noticeably between the first and last frames. I added labels to show the position of the planets and nearby reference stars. At the left of the image, you can make out the Milky Way and a number of star clusters.

To see the image in detail, navigate here and use the viewer to zoom in and pan around. You can also navigate here and see a version with all of the constellations labelled stretching along the zodiac from Sagittarius at the left to Cancer at the right.

As another processing attempt, I rotated the image vertically, and cropped off the uneven borders. I use the Photoshop plugin GradientXTerminator to help reduce some of the sky glow gradient. I also used the Photoshop plugin StarSpikes Pro 2 to give the brightest stars a bit of extra punch. The planetary symbols took a bit of hunting. I found them in the DejaVu Sans font.

My brother-in-law, Ross Cunniff, braved the cold Colorado dawn to create some interesting images.