Tuesday, May 26, 2015

Titmouse Chicks Develop

This is a continuation of our monitoring of the Black-crested Titmouse pair in our nest box.

May 26 - In the evening, I grabbed another color image of the nestlings at 3 days old. Note that along the crown, back, and wings, dark patches are developing where feathers will grow. They look like centipedes attached to the chicks. The female seems to have spent longer periods of time away from the nest box today.

May 27 - Watched an episode on video where female brought fed a large worm to one of the chicks which later regurgitated it, spending nearly 30 minutes trying to expel the worm from its mouth.

May 28 - This morning, on her first departure, the female removed the large snake skin piece from the nest box. This evening, another still shot of the chicks shows that the older ones have feather patches on their foreheads and dorsal line as well as further development on the trailing edges of wings, plus more differentiation between the eye globe and the place where the eye opening is.

May 29 - Some interesting developments today. First, we saw one of the larger chicks making repeated thrusts, trying to push itself out of the nest cup. You can see this in the infrared image below. Second, the female has started removing larger fecal sacs from the nest box rather than consuming them on the spot. Finally, we are seeing new details on the developing chicks, In the color picture, you can see further feather growth, scales and claws on the feet, and a more definite eye slit and ear hole.

May 30 - Last night, the female spent stayed away from the nest box again. Her last feeding was around dusk. Overnight temperature low was 70F, compared to 66F past few days. Perhaps she thought it was too warm to brood on the nest. She returned at 07:00 with another large caterpillar and did diaper duty, eating at least three smaller fecal sacs and then leaving with a larger one. Feeding arrivals have continued at about 10 minute intervals again. My necessary weed-whacking in the vicinity of the nest box did not interrupt feeding arrivals though when I made my closest and noisiest approach, she did stay in the nest longer than usual.

The largest chick shows wing development as it pushes out of the nest cup. In the video snippet it shows early preening behavior.

Progress shot shows obvious feather growth

Looks like mom is sleeping elsewhere again tonight. Seems that brooding is over for this batch of chicks. We watched a video on-line in which a Tufted-Titmouse family was filmed with a webcam. In that sequence, we saw the male participating in feeding both the female as well as the young. No idea what happened to the male of our pair. Are Black-crested different in that regard or did the male get killed early on?

May 31 - Morning feedings today consisted of much larger food items including moths and legged insects. She has some trouble getting them oriented correctly to go down.

This evening's progress image shows partially open eyes on the two oldest chicks and continued wing development. Tomorrow was the day we expected the eyes to open.

June 1 - Regular feeding cycles again today. During the heat of the day, the chicks seem to be spreading themselves out to cool down. They try to stretch their necks far out of the nest cup. Eyes on the two oldest chicks were partially open as of yesterday. Images and video highlight how much of a developmental gap there is between the chicks that hatched on May 23 and those that hatched on May 24. There seems to be more than one day's difference in growth, probably because the larger chicks receive more food or (possibly) because those two eggs received extra incubation before the other eggs were laid, though we can't be sure that the eggs that hatched first were laid first. 

The infrared video shows that the bigger chicks are succeeding more often at getting fed.

June 2 - First round of the inevitable today. Overnight, the smallest of the nestlings died, most likely due to not getting enough food. The mother actually hauled the body off at around 09:00. That is pretty impressive. I feared that I would have to go out and remove it myself.  

This video shows the largest nestling testing its wings and highlights the huge size difference between the first two nestlings and the later ones. You can see how the larger chicks rise up to get food, so much so that the smaller chicks are almost invisible. Their mouths are certainly no where in range of the mother. I see no evidence of older chicks bullying the younger ones. It seems to be purely a matter of reach.

June 3 - Based on lack of breathing, it looks like another one of the two smaller chicks died overnight just after 05:30. The remaining small one is hardly attempting to open its mouth when the mother arrives. I assume it will not last the day either. Last night, we inserted a remote temperature probe into the nest box to get an idea of how hot it gets. Heat might be a stress factor but simple starvation seems more likely. Over the course of the day, the temperature in the box peaked at 93F, not much higher than the external peak temperature of 92F. This is some relief as our readings indicate that this is still a safe temperature.

At 17:45 I could see the third chick still moving its head and having labored breathing. By 20:00, there was no motion at all. Every on-line resource we read indicated that we should remove the dead nestlings. We were concerned that we are close to the time frame in which we need to stop disturbing the nest to avoid premature fledging. Since the female had made no attempt all day to remove the chick that died overnight, we chose to step in and remove both the dead chicks after the female had stopped visiting the nest for the day. Surprisingly, the older two did not react much to my pulling the bodies out from under them. I think that this is past their normal "bed time," so they were not expecting a feeding.

The progress pictures we took beforehand show tail feathers and also the two dead chicks.

This next video is a depressing as it documents the last moments I could find of each of the nestlings and subsequently their removal, the smallest by the female and the next two by hand.

June 4 - Two remaining nestlings still doing well. The received regular feedings. Further feather development but nothing distinctively different. The video sequence of one of them performing a more thorough wing-feather preening gives a good view of the head and eyes. After dark, we added a predator baffle to our external camera pole so that we could confidently move it up close to the nest box as we look forward to capturing fledging sometime next week.

June 5 - Continued progress on growth. This is probably the last evening we feel comfortable inserting the iPhone in the vent slot to get a color image. The chicks are acting much more alert to visual stimulus now.

Below, one of the videos shows wing spread out where we see all of the primaries, secondaries, and coverts. Another video shows a feeding sequence in which the chicks stand and flutter their wings. On the menu appears to be a new item - a large spider. Mid morning, while the female was in the nest feeding the chicks, the video captured a second adult titmouse landing on the nestbox, investigating the hole, and flying away.

After dark, I rearranged the cameras again. I moved the big security camera back to get a wide view of the possible tree into which the chicks might fledge. I mounted the second Hawkeye camera 18" away from the nestbox opening to get view of the female or chicks perched at the nestbox hole.

June 6 - Another episode in which the additional titmouse flew onto the nest box while the female was feeding the young. This was repeated three times. We saw snake-hissing from the female in response. The slightly larger nestling is still getting more of the food. I was able to identify 35 feeding arrivals by the female over the course of the day from 06;40 to 19:00.

June 7 - Another very hot day. Temperature in the nest box hit 95F late afternoon. I was able to identify only 29 feeding arrivals today. Both of these seem small. Smaller chick still not getting same amount of food. I observed the larger chick lightly pecking at the beak of the smaller.

There was also a repeat encounter with our interloper adult. This time we got a good mug shot of it. Here is a view of first the mother arriving to feed the chicks followed by the other adult who first comes when the mother is feeding, gets hissed at and then comes back to peer in to the nest box after the mother leaves

Another episode of interest was captured when we got back home today. At 16:54, the video captured the mother arriving at the nest box with a bug. Danielle was throwing a toy for Vali in the yard. The mother waited at the nest entrance watching the dog. Instead of going in, she headed back out, presumably to a nearby tree. A minute later she came back to the nestbox with the bug and did not pause as she entered to deliver it.

June 8 - Chicks are growing fast. They are almost as large as the mother, though not completely feathered in on the backs. Yet another round of the mystery adult at the nest box. There was at least one round where the female brought in a bug so large that neither chick could eat it. She eventually hauled it away.

June 9 - This is day 17 for these two eldest nestlings. In this shot the crest is evident as are the throat feathers.

We are very close to fledging. Today's milestone was that both nestlings got enough hang-time with their flapping to grab a hold of the slats on the inside of the box. One of them took a peek outside the box for the first time this evening at 19:11.

June 10 - Day 18 for the remaining nestlings, the latest day documented in Sialis for fledging of titmice.  Sure enough, today was graduation day. At 13:00 the first nestling had another extended view out the nest box hole. It fledged at 15:25, landing in the tree just next to the nest box.

The second nestling had a quick peek soon after but didn't jump... at least, not then.

My wife, who works from home, says that she checked the nestcam just before 17:00. and realized that one of the titmice had fledged. She went and checked around the box to see if it was on the ground, but she couldn't find it. Coming back inside to check the recording to find out when it had fledged, she caught the second titmouse preparing to jump and was able to watch it fledge live at 17:08. She went back out to see where the bird had gone and eventually spotted the whole family together in a tree in our neighbor's yard. Unfortunately they had moved on before she had a chance to set up the camera to get a shot.

It looks like the mom came back for a feeding at 17:07. Moments after the mom flew back out, the second nestling fledged at 17:08. It flew past the nearby tree and out of camera view. Curiously, at 17:38, the mother came back to the box with food for the chick and found the nest empty, which we think is after the time that Danielle reported seeing the whole family together. Perhaps the mom can't count and wanted to make sure that the nest was empty?

I got home from work at 19:00 and was not able to locate either of the fledglings. We have a definite case of empty nest syndrome!

See my YouTube playlist to watch a complete set of the titmouse videos.

Monday, May 25, 2015

Memorial Day Mammatus Clouds

After the day of severe weather in Austin with flooding and tornadoes, we observed Mammatus Clouds in the early evening.

This is the first time I remember a storm tracker putting a tornado path straight into our neighborhood. Fortunately, we did not get anything severe hitting us.

Saturday, May 23, 2015

First Titmouse Chick

This is a continuation of our monitoring of the Black-crested Titmouse pair in our nest box.

May 23 - Its hatching day and Memorial day weekend, perfect timing! Based on the time of the last egg, we had expected hatching to occur sometime over the last two days. The first egg hatched this morning at 09:00. The full hatching only took a couple of minutes.

In this first frame, the egg is just cracked at the top and the chick is pushing out. The mother participated in the hatching by poking and prodding at the egg.

As the chick wiggled a bit, the mother pull the egg shell halves out from under it and ate them both. Readings indicate that she might be re-absorbing calcium or just taking out the trash. That complete, she settled back on top of the nest and brooded some more.

At 10:00, we got another glimpse of the chick, this time begging for food.

At 10:10, the female left the nest and I took the opportunity to slip an iPhone through the ventilation slot to grab a picture without opening the nest box. The snake skin can be seen on the far left edge of the frame. I think that it is a piece of plastic trash that is lying on top of the chick. The female repeatedly tries to get the debris off of the chick but never moves it far enough. This color photo is the first time we have seen the speckles on the eggs; they do not show up in infrared at all.

Below is a link to a short video of the hatching sequence. In it, the female move out of the nest cup when the egg cracks. She then picks at the egg shell, eventually removing and eating each half in turn. At the end of the sequence, she feeds the chick some sort of scrap she picks up out of the nest.

The second chick hatched at 13:25 while the mother was away. Over the course of the afternoon, the first chick received all of the bits of food that the mother brought back to the nest.

There have been two other titmice frequenting the yard and the feeders. One dark crested and one that looks like another hybrid. Our female does not ever go to the feeder but regularly leaves the nest box and heads back away from the house towards the river. I assume that feeder food is not appropriate for the nestlings that probably need a diet of caterpillars. We have seen no evidence of any male helping out with the feeding. From our readings, I had thought that the male would help feed her.

May 24 - Two more chicks hatched overnight, one at 02:04 and one at 07:45 based on when I could see the mother eating egg shells. The video also captured her removing fecal sacs by eating then. She seems to have some trouble gauging the size of food that the chicks are capable of swallowing. On one round, she repeatedly stuffed a piece into one mouth after another, removing it when the chick could not swallow. She finally ate it herself. Here is another quick iPhone-through-the-vent shot at 09:45, an hour and a half before the last egg, isible in the photo hatched.

Mid-morning, something must have spooked the mother just after she came back into the nest. She guarded the entrance with a "snake-hissing" display as captured in this short video clip. Unfortunately, I had moved our outside camera to observe the raccoons that were tearing down feeders so I did not get video of what she was hissing at. Note the chick which was just fed expelling a fecal sac just before the mother begins her display. This is the white bit she picks up when she settles back down.

I grabbed some shots of the female leaving the nest box. These shows the coloration on the light chestnut forehead and pale gray crest which I am still assuming marks this as a Black-crested x Tufted hybrid.

The final chick hatched at 11:12 this morning. It took just over 24 hours for all of the eggs to hatch which is pretty close to the expected range. Here is a rare moment when all five mouths are open at the same time.

This is another iPhone image taken of all five chicks. I find it interesting that the only feathers that they hatched with is the tufts coming out of their crown. It is amazing that in a few weeks, these things will be able to fly.

Here is a very brief video snippet of the five

After the snake-hissing behavior earlier today, we decided up the ante on our house-sparrow deterrents. We put together a "sparrow spooker" to further discourage house sparrows from approaching the nest. On her first return to the nestbox after we installed the spooker, the titmouse did not even notice it and went straight into the box. However, on her second return, she did see it and was, herself, spooked. She made five attempts hovering in front of the box and escaping back to the nearby tree before finally taking the plunge into the hole. This had me concerned, so I kept watching the box. On a later arrival, I saw her once again enter without hesitation. Hopefully, she will adjust to the new decor quickly.

May 25 - This morning I took a slightly longer color video of the nestling with the iPhone. 

This afternoon, we had heavy storms and numerous tornado warnings throughout the Austin area including one that bore down directly on our location in Georgetown. During the worst of the downpour, the female did not stay in the nest box. This surprised me. Is it a coincidence or did she find better shelter somewhere else?

The female made many repeated trips in an out of the nest box with no problem. I think the spooker is no longer a concern for her. Typical  feeding schedule today has been: brood on the nest for 10-15 minutes, leave to forage for 2-5 minutes, return and take 20-30 seconds at most to feed one chick and eat any fecal sac, repeat. She has been taking less time to find food today than previously.

Story continues with chick development.

Thursday, May 21, 2015

Raccoon vs Nut Feeder

Over the past week or so, we have had our bird feeders pulled down off the trees and torn apart. Danielle reattached the feeders with steel cable. Though the feeders now stayed on the tree, the contents were still being emptied. I moved the security cam to point at the bird feeders and found the culprit on video ... a raccoon.

Saturday, May 16, 2015

Another Visit to Murphy Park

Near sunset this evening, we made another trip to Murphy Park in Taylor TX to see the egret rookery. Compared to last year, there were considerably more Cattle Egrets as well as an assortment of Great Egrets, Snowy Egrets, and Little Blue Herons. We did not see any night herons this year.

Cattle Egret
Cattle Egret
Cattle Egret (Danielle)

Snowy Egret
Snowy Egret

Juvenile Little Blue Heron (Danielle)

Great Egret and nestlings
Great Egret and nestlings, Cattle Egrets (Danielle)

Camera Box Invasion

Went to check on the inside of the larger (owl) nest box today after having seen some bugs in the videos.  What a disaster. The leaf material became a nice habitat for roaches of which there were all sizes that scampered out as I removed the litter.  The camera box itself had become a cozy ant nest with hundreds covering every surface. Even ten minutes after pulling the lot down, there were still quite a few die-hard ants remaining. Back to the drawing board on how to set this up. The small nest box has not been a problem because it is more isolated from the ground or any trees.

Sunday, May 10, 2015

Mustang Island May Trip

Below is a slide show of birds from our May trip to Mustang Island and surrounding birding locations.

Wednesday, May 6, 2015

First Titmouse Egg

This is a continuation of our monitoring of the Black-crested Titmouse pair in our nest box.

May 6 - This morning, the female returned to the nest at 06:55 with no materials. She shuffled around the existing pile for several minutes and then settled down, occasionally moving bits around. She appears to have laid the first egg between 07:00 and 07:05 after which she pulled back to quickly look at it and resumed sitting on it and pulling materials around. She left the next box at 07:20 after what seemed to be a "recovery period."

I was surprised that the egg was laid today as the nest had no well defined central structure. I gather that the titmouse has a range on how much of a bowl is formed before laying begins. Sialis has a nice set of pictures of various titmice nests and a good description of the nesting process.

During the course of the day, she made 4 more deliveries of grass and fur at 11:40, 12:59, 14:35, and 15:53. During this process, she ended up covering the egg completely.

At this point, we are expecting eggs to be added, one each morning, until she is ready to start incubating the full clutch. Still no certainty that she will not abandon the nest so we will continue to avoid the area of the yard where the nest box is located.

May 7 - The female laid a second egg this morning between her initial arrival at 06:40 and departure at 07:15. The DVR skipped recording much of the intervening action.

This titmouse is definitely not following my script. This evening, she came back to the box at 20:00 and has not left. She appears to be incubating already with only two eggs. Sialis says that incubation begins after laying the penultimate egg and that three to nine eggs are laid, five to seven being most typical. So, she might lay a third egg, though it might not be viable.

May 9 - There are definitely at least three eggs in the nest as can be seen from this image just before her daily departure this morning.

May 10 - Now up to five eggs, so she is actually still on schedule for one egg a day.This shot taken just after she left the nest at noon. I am still confused as she still seems to be incubating. Is she, perhaps, not really heating them, just resting above them?


May 11 - Still clearly five eggs in the nest this morning as observed at 07:50 after her morning departure.Over the course of the day she left ten times,remaining away between 10 and 15 minutes. Several of those time she returned with additional nesting material, dropping it near the nest cup, and incorporating it later after she had settled her self back down.

May 12 - Still five eggs and continuous incubating except for 10 minute exits. With the new fur and continual scooting around over the eggs, a well defined nest cup has formed.

May 15 - I was surprised to observe that the female spent the entire night from 20:50 to 07:15 away from the nest box. I have also not seen the male since nest building completed. I had thought that he would be feeding her during this time. Is that why she was away ... an unwed mother struggling with a night job? Anyway, today back to the usual routine with eight absences of 10 minutes each.

May 17 - We added a bug attracting light in the yard last night. This morning at 09:00, the presumptive male made a quick landing on the roof of the nest box, flew down to the opening and then flew away. We did not hear any calls between them on the video, though she did react slightly to some noise. The male did not bring any food.

May 18 - Another day of regular trips away from the box with material brought in to augment the nest. At noon, she brought in a large chuck of snake skin. My readings indicate that this material is added to the nest to discourage egg predators. Research has shown that predators such as flying squirrels are less likely to predate a nest with snake skin in it.

May 20 - Another day of brooding and bringing material after her presumed feeding trips. She brought in another big piece of snake skin. Seems that she just about has a full snake in there.

All monochrome images taken with Hawkeye Nature Cam from birdhousespycam.com capturing in infrared mode.

Story continues with egg hatching.