Thursday, February 27, 2014

Downy Woodpeckers at the Feeder

This week, a pair of Downy Woodpeckers has been frequenting our feeder station. I wonder if they are nesting near by.  The first picture is the male, the second is the female. Seeing these caused us to do a bit of research on how to distinguish Downy and Hairy woodpeckers as they look very similar.  The key difference seems to be the size of the bill relative to the head. To me, however, the bills in our pictures look somewhere between the description of the Downy and Hairy. In the end, we measured the feeder to estimate that these birds are only between 6" and 7" long which rules out the Hairy.

Update 2014-03-04 - After an icy night, a Downy Woodpecker and Carolina Wren on the suet feeders. The male Downy showed up just after this female left. I never see the pair at the feeder at the same time.

Sunday, February 23, 2014

Red-Shouldered Hawks Mating

While working in the front yard, I suddenly heard the repeating frenetic call of a hawk. Looking up into the trees across the street, I saw a pair of hawks mating. Not having a camera to hand, I did not have catch any of the action but did get a shot of the female still perched in the tree shortly after the male left the scene. The shoulder patch is not as distinct as I had imagined but the courtship call was unmistakable. This is a new species on our list. Though I am sure we have seen them before, this is the first time I have confirmed the identification. Images taken with Canon 60D / EF 70-200mm f/4L.

Sunday, February 16, 2014

Final View of Llano Eagles

Today is likely our final observation of the Llano Bald Eagle nest for the 2014 season. We tried yesterday afternoon as well but wanted to try again with less back-lighting. We did get this cute image of the chicks looking up at one of the adults.

Trying for better lighting, we decided to catch the "golden hour" at dawn, a real challenge for us. We got up at 5:30 and made it to the nest site by 7:00.  Unfortunately, the nice forecast did not hold out and we had very overcast skies and still no front lighting. We were the second group on site and, by 8:00, there were a dozen birders watching the antics of the chicks. In the photo below, I am in the red jacket. The nest is out of view to the left.

The aerial map below shows our observing position and my best guess of the nest location which is about 80 feet away. The map shows how the eagles have convenient access to the Llano River for fishing and scavenging, a fact not evident from the road.

Here are the chicks. Wow, they have grown since our last visit. They have a full set of primary and secondary feathers and appear ready to fledge in a few weeks. Our understanding is that the chicks were born around Dec 18, 2013 making them about 9 weeks old now. We watched them execute some vigorous wing flapping and one actually ventured a few moments of hang time, letting go of its branch.

Having gotten to the site so early, we were able to see a few rounds of the parents flying in and out of the nest. On one pass, they brought a small fish and the chicks pounced on the meal.

Interestingly, on the rest of the deliveries the parents only brought sticks and twigs, much to the chagrin of the chicks. I wonder why they did this? I can understand holding back on food to encourage the chicks to fledge, but why bother with the extra building material?

The YouTube video below is a composite of three segments we filmed corresponding to the scenes above. We removed the sound since it is mostly noises of cars passing behind us and shutters going off everywhere.

Sunday, February 9, 2014

Owl in Hoxie Bridge

This afternoon, we went geocaching at Lake Granger, a half-hour drive from home.  We picked up various caches along the Comanche Bluff Trail. While searching for a cache on the Hoxie Bridge, we got a bonus ... a close up encounter with an Eastern Screech Owl.  We have heard them many times around our house – they have a very distinctive horse-whinny sound – but have never gotten a close look at one. The yellow circle in the image below shows where this one was roosting for the day.  This is within a few meters of the cache's hiding place. This owl, or another of the same species, was photographed in the bridge's iron works 2 years ago as well.

Here is a picture we took of the owl on the way out along the trail. I estimate it to be about 8" long. I first spotted the tips of its tail feathers dangling down below the beam and went in to investigate, wondering if it were part of the cache container.

We left it to snooze and checked up on it on the way back. It had moved so that its tail was no longer showing.

It was a good day for animals. The owl was at the first cache we found.  Just next to the second cache, we saw a huge opossum, though he scurried out of sight before we got a picture.  Then, just before we got to the third cache, I almost stepped on a nice snake lying motionless across the trail.  At first, I thought it was a plastic snake put there as a joke, since it didn't move. It started to wake up as I moved it off of the trail. It looks like a Rough Green Snake (Opheodrys aestivus), a non-venomous insect eater found near water.

After I moved it off the trail, it slithered away into the greenbriar patch. Greenbriar is a nasty climbing vine that forms brambles throughout the region. I am sure that greenbriar was the inspiration for barbed wire. That stuff would prove to be our nemesis throughout the afternoon; we both got cut up, and I lost my sunglasses at some point while forcing my way through a patch.

Saturday, February 8, 2014

AR1967 Heads Over Horizon

I did not have a chance this week with the weather (freezing and overcast) to see the large sunspot complex AR-1967 until today. It is now about gone over the horizon of the solar disk. The images below are taken with a Lunt LS60T/PS Hydrogen-Alpha solar telescope and an Imaging Systems DMK41 monochromatic video camera.  The first image was created from movie frames at a single exposure. The second image was composited from frames of two exposures, short exposures for the solar disk and longer exposures to capture the details in the solar prominences.

Sunday, February 2, 2014

12V Outlet for Trailer Macerator

This post details the installation of an external 12V outlet on our Jayco 28BHS trailer for use with a Flojet portable macerator pump.  This outlet will save me the trouble of maintaining a separate battery to power the pump.This first image shows where I installed the receptacle, just forward of the gray water drain line and with convenient access to the sewer drain onto which the macerator pump mounts.

The receptacle is a Sierra WH10520 unit intended for trolling motor applications.  I obtained this, and the matching plug, at West Marine. The receptacle is rated to handle the peak 20A that the macerator pump can draw. It has 8 AWG leads, and I purchased 22ft of similar cable from West Marine to route to the battery. This gauge wire gives a 5% drop over 40ft at 20A and a 3% drop over 40ft at 10A. This seemed adequate for the application.

I found a heavy duty angle bracket in the deck-building section of Home Depot and drilled a hole through it to mount the receptacle. I covered the cable with a plastic split loom and attached it along the length of the trailer with wire retention clips, using the existing screws with which the thermal cover is fastened to the trailer frame.

The final exterior attachment point is shown below.  This is just rear of the front-left stabilizer jack.  Here the thermal cover is notched to avoid a cross beam.  I routed the cable up into the space between the thermal cover and the Tyvek insulation barrier.

The cable enters the front storage area through the floor near the back wall -- shown at the bottom right of the image below.  I drilled a hole through the floor plywood and used a sharpened dowel to punch down through the insulation and the Tyvek barrier, meeting up with the cable exit point shown above.

From my previous solar panel project, I had already created a utility panel to mount the solar charger and inverter.  I added another 25A resetable breaker from West Marine through which I connected the external receptacle feed to the main battery lines.