Thursday, May 26, 2016

First Martin Visitation

Within the first week of putting up the purple martin house, I trapped and removed three house sparrows from the colony using a spring-loaded trapdoor device. The starlings proved not to be a problem. Unable to enter though the starling-resistant holes, they soon gave up and left. This past week, I have been wrestling with a pair of sparrows that keeps building nests but is aware of and avoids the spring door.

May 26 - This morning, about a month after deploying the gourd rack, I was excited to see that a pair of adult martins was checking it out. From the picture, I think a ASY-M and SY-F. I went out, lowered the house, and disarmed the trap. When I put the house back up, the martins came right back. However, I was shortly dismayed to see the male house sparrow dive bomb the female martin and harass her towards the ground. I am not sure what my next step is to remove the sparrow which seems to have mentally claimed the whole colony.

May 28 - Looks like this pair did not stay over last night. I have to assume the aggressive neighbors were not to their liking .... Actually, I am not sure what they are doing. No sooner had I posted the update, but the martins came back and hung out in their gourd for an hour. In the evening, I once again did not see them come to roost for the night but did see a number of martins feeding overhead and towards the river.

May 29 - Again, I never saw them return before dark last night. This morning, three visitors. I think it is the original two plus another arrival which I have not been able to see closely enough to determine if it is another female or an SY male. A female went straight for the same gourd as before. No materials brought in yet. Late morning, I spotted the female bringing a green leaf to the nest. All of this activity is in the gourd with the decoy bird above it. Looks like the third bird is a SY male. It has strong blue head and blue breast feathers

All three birds visited the colony periodically during the day. After having been gone for several hours late afternoon, the came back soon after 7pm when my automated "Songbird Magnet" came on to play martin noises. I am fairly sure the dawn song that this device plays in the morning attracted the first set of martins. They only stayed a quarter of an hour before going back out for more feeding. Late in the evening, I saw the pair perched up on our antenna pole. I did not see if they went into the houses after that.

May 30 - Stormy night and rainy morning. Three martins out for dawnsong. Came and went from the colony during the morning. Unlike the two males, the female has some difficulty in exiting the gourd through the Excluder II holes. She has to get some leverage and give several pushes. I saw the female bring in one more green leaf. Again, all were gone most of the heat of the day. The House Sparrow pair, however, diligently works on building the nest all day. I gave up on the trap door. Every time, I placed it in a gourd, they moved to a new one. During the evening, I watch about 8 Purple Martins, 6 Chimney Swifts, and 4 Common Nighthawks foraging in the air overhead, mostly over the river. My pair came in several times to rest on the antenna pole. I saw them circle down, burbling, and land on colony at 8:25pm. As usual, the female lands on the porch and the male on the perch rods above. They stayed for 5 minutes and then entered their gourd together. I did not see the SY male return to the colony.

May 31 - Found pair on antenna perch at 7:30am. Stormy afternoon. Fewer martins and swifts tonight. Nest check at 8pm found another green leaf. Pair landed again in evening at 8:10pm. An SY male (same one?) circled around them attempting to land on antenna. ASY male seemed to chase it off. SY male engaged in some aerial interaction with another martin and the pair drifted off to the south and did not return. Pair entered gourd at 8:30pm.

June 1 - Yay, the Purple Martin pair in the gourd which I have now labelled "A" have produced one egg. Unfortunately, the House Sparrow pair in gourd "B" also laid an egg today. By the way, these gourds are labelled sequentially with "A" facing NNE, "B" facing NE, all the way back around to "L" facing N. I am having a hard time finding labels that stay stuck to the polyethylene gourds. Anyway, not sure if destroying the sparrow nest will trigger a destructive behavior by the male on the martin nest so I am leaving it alone for the moment. During the morning, I saw the male also bring in a green leaf. Looks like they brought a bunch in during the day. Before bed time, we had another group of 3 martins that made close passes to the pair including one that attempted to land with them. None landed on the rack however.

June 2 - And then there were two ... the martin pair produced a second egg as did the sparrows. I tried to addle the sparrow eggs quickly by shaking them. Ended up cracking one of them and discarded it. In the evening, I missed the 8:30 fly-in. However, at 8:55, I did see a pair of screech owls on the power line in front of the house staring at the rack. I had hoped to attract owls in the past but now that I have martins, not so much. We have owl guards above the upper gourds, however screech owls are pretty small and could get past. Forum reading indicates that these may not be a big risk to the martins and the SREH holes should keep them from nesting in the gourds.

June 3 - As I was leaving in the morning, I noticed another SY male on the "E" gourd. Same as I saw one before. From the plumage comparison to the image above, it might very well be the same one but I am not positive. As expected, three eggs now in the nest. The pair did not come back this evening by dark. They hung around at 8pm, but then left as a storm approached.

June 4 - All three martins were active at 9:30 when I went out to check. The SY male was looking into various cavities including the "A" and "B". It got a good thrashing by the male house sparrow. At my 4pm nest check, I found 4 martin eggs in "A" but still two sparrow eggs in "B". I saw several martins high overhead at 7:30pm but was not home for the usual return.

June 5 - They are still laying. This afternoon, I found five eggs. As I worked in the yard, I noticed that the female spent more time in the gourd but often just on the inner porch looking out. I observed two SY males investigating gourds this afternoon.

After seeing some horror pictures of rat snakes that had bypassed the commercial predator guard, I fabricated a variant of the snake guard designed by Chuck Abare. It consists of a skirt of bird netting pinched between two disks of cedar board. The disk is split down the middle and hinged so that it can clamp onto the pole (using two clasps) and can be removed to lower the rack. I did not not need to fasten a worm clamp to the pole to hold up the disk as described by Chuck. The premise is that the snake will attempt to slither through the netting and become entangled in the process.

June 6 - Still only 5 eggs this evening in "A". The martin pair will have started incubating yesterday, consistent with more observations of the female in the nest. Based on average stats, hatching is likely to begin on June 20 and the earliest fledging on July 16. Likely fledging is from July 22 to 26. The sparrow nest in "B" had three eggs and a lot of feathers lining the nest cavity. We pulled them out and coated with vegetable oil as an addling technique and put them back. Did not have time to let them dry first.

June 7 - No change. I did a quick nest check without disturbing the leaf cover over the eggs. Nothing looked disturbed. Female fled as I was bumping around to bring the rack down. Not sure how to let her know a bit more ahead of time.

June 9 - No change on nest check. Saw female watching out the front porch. Also saw a sub-adult male on the "E" gourd in the morning. This evening I was able to speak with the martin landlord a few streets over. He has problems with owls and hawks ripping into his metal house.

June 10 - No change on nest check. Observed once this morning and twice this evening the SY male trying to attract the paired female including waiting on her porch and poking its head into the gourd. These efforts seem to be timed for when the ASY male was away. The younger male actually looks to be a bit bigger.

June 11 - Still incubating. This afternoon I saw three other martins visiting the yard, swooping around the rack and trying to land up on the antenna. The SY male still thinks he can succeed at courting the paired female - very odd. The temperature has risen sharply this week and I decided that I really should have put vents on the gourds earlier, so now is the time before there are nestlings. There are mixed reports about how effective these are but they can't hurt. I brought down the rack and detached one gourd at a time and modified it. I did several other gourds first to practice the technique before I did the one with eggs...yikes. To start, I opened up the hatch and put in a plastic bag to catch shavings. Using a 1" forstner bit, I drilled a hole in the stem of the gourd on the side opposite the entrance. I applied some silicone sealant to the threads of a 3/4" PVC elbow joint that is threaded on one end and slip-fit on the other. I then pressed in and screwed the fitting in snugly, spreading out the sealant.

June 14 - Still incubating. No change to the contents of "A". Female is in the gourd most of the time. For better or worse, today I changed up the sparrow issue. I disposed of the nest and three previously addled eggs from "B". I then set door traps on "B" and the next-door lower gourd "D". I left the upper "E", which the SY male lands on alot fully open. I then put clothespins across all of the other holes to block them. The fear here is the the possible revenge actions. However, I have not seen much action in and out of "B". I think the sparrows know the eggs are not viable. The male has been probing all of the other cavities.

June 18 - Still incubating. No change to the contents of "A".  As described in a separate post, I installed a camera in gourd "A". Hopefully, I will bother the nest less frequently as a result. Both due to some additional heat generated by the camera and due to a mini heat wave we have started feeling, I jury-rigged a sun shade for gourd "A" by zip-tying a piece of aluminized insulation wrap onto the owl guards. In this picture, you can see both the final camera assembly covering the access port and the tent. Late morning, I observed a group of additional martins, possibly all SY males, circling around the colony. Just in case any decided to probe spare holes, I move the clothespins again, covering the traps in "B" and "D" and leaving open several on the top level, "A", "C", "E", "K". The tenacious little house sparrow has not yet found a mate but still centers his attention around "E".

June 19 - This morning I was able to watch the overnight video coverage. The male never came into the gourd during night. I was surprised how much time she spent preening, of the type to remove parasites rather than to straighten feathers.

This evening we had the first two hatchings. One at 18:50, then next right after at 19:10. This animated snippet of the first chick trying to rid itself of its egg shell helmet is priceless. Both happened while the parents were away. When the female came back at about 19:40, she ate the egg shells to recover the calcium.

June 20 - By this morning, a third chick has hatched, though have not found the spot in the video recording where the female eats that shell. The male has no started making appearances in the nest though he still did not spend the night there. Hard to tell due the angle whether he is feeding but he does lie down and cover them. The fourth chick must have hatched just before 09:45 since I saw the female eat another egg shell at that time. By end of day there was still one egg left visible occasionally under the leaves.

Feedings happened continuously, both parents contributing. Often, one parent stands guard on the inner porch waiting for the other to come back. Evening feedings, however seem to be done only by the female. Presumably, the male has gone off to his normal roosting spot.

Final chick hatched at 20:55 this evening. This is only 26 hours after the first hatching so there will not be too much age span between the chicks. After watching the younger Titmice starve last year, that is a bit of relief.

June 21 - Feedings progressing as usual. None of the chicks seem very energetic about mouthing for food. Just young or too hot? Here is the five-some having a nap

Intensive feeding by the female occurs at dusk when I am sitting in the yard watching. She makes runs about every 3-5 minutes, stopping in the nest only long enough to poke some food in a mouth and grab a fecal sac. She leaves the nest in a very low flight path over the carport, east towards the river. She always returns over house and along the courtyard from the northeast, straight into the nest.

June 22 - Everyone is a bit larger today. I noticed on the camera replace some sort of little bugs on the chicks. Are these possibly mites? Not sure if it is too early for a replacement of nesting materials and, during the evening, it is too much in the middle of prime feeding time to interfere. I am surprised how big of a mouthful the chicks can swallow. Today, several occasions of entire dragonflies swallowed.

June 23 - Size progress image shown. No interesting events observed during the day. In the late evening in IR footage I saw several mosquitoes landing on the female and on the chicks... yuck.

June 24 - This morning, I brought the rack down to close off a gourds "E", "K" on the top level where the sparrows were getting too active and reopened "B", "D" containing the traps. I took the opportunity to put and iPhone into the opening of "A" to get a more detailed picture of the nestlings. This both to see more of the incoming feather detail and also to look for parasites.

June 26 - Very hot day today in the high 90's. Feather detail continues to develop and noticeable darkening of the skin color. The largest of the chicks has pin feathers along the primaries and secondaries poking out. In the evening, I tried some flash photos of the adults landing at the gourd but have yet to process them.

June 27 - Looks like the nestlings are going walk-about. One decided it might get better pickings up near the door. That did not seem to pan out for it. Seemed that there was still better luck in the center.

June 29 - This morning, another three SY male floaters circling around the rack. I think they come for visits from the nearby colonies. The chicks not only have pronounce pin-feathers along the wings but are getting them at the tail. They also have their eyes open more consistently. I am still worried about the amount of food the runt gets - never seems to aim his mouth the right way. I think we are at 10 days for the oldest chicks and 9 days for the youngest.

June 30 - One chick seems determined to hang out next the porch and to try to get on. I hope this second to smallest chick, hiding at the far end in this shot, does not turn into a jumper.

July 1 - We were able to see two of the chicks from the outside of the gourd as they rested their heads on either side of the inner porch.

July 2 - Today was a big big day ... nest change time. Though my video monitoring capture very few critters moving around, I decided to do a 12 day old nest change as recommended. If nothing else, to give me practice before I get a colony with multiple nests.

I decided to do things a bit differently since most of the gourds are empty. Yesterday, I pulled one of the empty ones from the back side down and cleaned it thoroughly and replaced the straw with fresh material. I put down half of the straw, sprinkled 1 tsp of 5% Sevin powder, and then added the remaining straw. This step is controversial. I also threaded some cord through a foam block to plug the front hole. This step is to keep excited chicks from jumping. This proved to be unnecessary at this age.

Late this morning, with Danielle serving as the "press photographer," we went at it. I first detached the predator guards and lowered the rack. I then removed the "A" gourd with the chicks and set it down safely. The camera assembly stayed dangling from the rack. I then mounted the new gourd in its place. I could then quickly transfer the chicks from the old gourd to the new one without the need for an intermediate bucket to store them in. Each one got a closeup mug shot on the way over. Here are a few of the better shots.

This procedure allowed me to completed the transfer in less than five minutes. However, the plan did not go completely smoothly. The first problem was that the loop of cord on the foam got tangled on the porch so I was not able to pull the plug free remotely. I had to lower the rack to fix the design. Second, I forgot to check the alignment of the camera before raising the rack. I had to lower and reset a second time.

While we were at it the parents came back and fussed. Here is a shot with both of them landed on the top perches, the female with a nice dragonfly ready to feed. After getting everything back up and cleared away, it took about 30 minutes for the adults to venture back into the nest. They made a number of fly by passes without committing to landing. The male, especially, took responsibility for investigating. He then perched above the unit on guard when the female finally came in again.

The nest change did give us the benefit of getting some quick macro shots of the nestlings. Here is some feather detail from one of them. It shows some downy feather on either side of the image. In the center are the flight feathers on the wing unfurling from the shaft. Zoom in on the image for more detail.

There were very few mites present, all told. These two zoomed in images are from the first nestling photo in the sequence above. The image on the left comes from the top of the chick's head. It looks like a Ornithonyssus sp., or Bird Mite. The image on the right comes from the edge of the chick's bill. I think this is a Dermanyssus sp. As I was removing old straw from the gourd a half dozen of these got on my hand.

I have to decide whether to bother with the second nest change next week. I suspect I will skip it since there were so few parasites on this first pass.

July 3 - Some of the chicks continue to rest their heads on the inner porch. I am assuming to get fresh air. The three smallest tend to hang out on the side furthest from the camera. Here are two of them peeping out.

July 4 - Today, for the first time, I saw one of the chicks crawl completely up onto the inner porch. It was the little, super-active one that always has its head up on the ledge. We also had wing flapping sessions, both by the larger and smaller birds.

July 5 - Today was a very hot day with a heat index of 107. The nestlings seems to have made it through OK, spending most of the day "bellied up to the bar" to get fresh air. Some excitement today. The usual morning arrival of SY males got interesting when one entered the gourd and started harassing the nestlings. Eventually, our male showed up, dropped off a moth in the mouth of one of the chicks, and the went about aggressively evicting the intruder. I posted a video of this on YouTube.

July 7 - The chicks have gotten more aggressive about getting up on the porch though often fall off trying to flap up.

July 9 - Now, several chicks are to be found calmly perched on the porch, others squatting below. Seems that the adults no longer able to remove the droppings. The floor is now well splattered with them. This morning around 10:00 we had a total of 7 visiting martins. I saw at least two adult males, and possibly one female. Surprisingly, they stayed around for about 2 hours making a number of group landings. In this picture we see the chicks but neither of the parents who were usually guarding the nest entrance.

Much of the feeding is now on the porch with the parents not entering the nest box. This has me concerned as I am not seeing our runt having any luck in getting it head out the entrance. In this shot, I managed to catch the male swooping up for a dragonfly deposit followed by the chick swallowing the prize.

June 10 - Our large group of visiting floater males was back again this morning. Late in the afternoon, we performed a second nest change. At between 20 and 21 days old, today was the final opportunity. It would have been better to do it a day or two earlier but Danielle was not available to help yesterday. Though not strictly necessary since the parasite count was so low last time, I did want to get some follow-up detailed photos of the nestlings. Same procedure as before; we pulled a spare gourd down and prepared it the day before. This enabled a very quick transfer with the new gourd placed in the original location. No playing "where did my chicks go" with the adults! This time, the foam plug trick went smoothly and the full transfer time was less than five minutes including class pictures. Having the video stream is a great way of ensuring the chicks are calm before opening the entrance. After today, no more taking down the rack until this bunch fledges in about a week.

In this first shot, I am taking the old gourd down from the location. The subsequent shots are each of the five nestlings in no particular order. I did not find any parasites this time, though the feathering might make spotting them more difficult.

The Travis Audubon's Society reports that Purple Martin roosting has already begun in Austin. The frist scheduled "Purple Martin Party" was this weekend. I guess our little guys will be fashionably late.

July 12 - Everyone settled in nicely after the nest change. There is a lot of wing flapping going on. All feeding is still at the gourd entrance with jostling for a position at the bar.

July 15 - Spent much of the day outside, while electricians working on the house, trying to get shots of feedings. Makes me appreciate just how fast of a landing the adults make on the ledge as I tried to time the shots. I must have seen 30+ dragonflies get fed over the course of the day along with some moths, beetles, and other odd insects.

I also observed SY males landing on or near the porch. The nestlings seem to know this is not a food source. So far no aggressive attempts to pull the nestlings out.

July 16 - Looking like fully feathered birds. We are now past the earliest fledging and can expect them to leave early next week.

July 17 - This may be my last chance for daytime photos of the nestlings. Here are some close shots of jostling at the entrance. I also posted a short video sequence.

July 18 - Big excitement today. One day before the expected day, two of the nestlings fledged. One at 7:40 and one at 10:00. During the course of the day, the remaining three were fed at the gourd. In the evening, one came back to the nest at 15:25 but the other stayed outside all night. We saw it hanging around with the female on the antenna and power lines.

We last saw it heading over the trees to the south at dusk. Maybe it went to check out the neighbor's colony.

July 19 - This morning, two of the chicks, presumably the fledglings, left at 8:08, one right after the other. One returned for a spell at 11:42. Two then left one right after the other at 15:01. The final fledging occurred at 15:06 leaving the nest empty for the first time. Hey, didn't I just clean that nest out last week?

When I got home from work, one fledgling was perched on the gourd rack waiting for feedings which didn't come though the female alighted nearby. Despite the dim light, some good poses for the camera.

By evening, four had returned to the gourd for the night. Presumably the one that flew away yesterday has a more independent streak than the others. Here is a video sequence of the fledging.

July 20 - This morning, two of the young left just after 6:30 and the remaining two just before 8:00. There were no visitations to the nest all day. I also did not see the gaggle of SY males visiting the colony this morning. When I got home at 19:00, there were two in the gourd and one on the antenna. As I watched one of the young at the entrance to the gourd through my spotting scope, I could see three or four critters crawling around its head shaped like small termites. I am guessing they were some sort of bird lice. I also saw the female investigating some of the other gourds on the rack, something she has not done up until now. By 20:15, five fledglings were back in the nest and the female was on guard on the antenna after having made a number of feeding runs to the nest.

July 21 - The full bunch spent the night in the gourd until dawn. I am still not sure which birds I was seeing in the images. One bird spent the entire night on the inner porch "on guard". I would have imagined that to be the female except I saw five young in the nest last night at the same time that the female was up on the antenna.

This morning, three left at 6:36; the two stragglers left at 6:38 and 6:42, probably waiting to see if breakfast-in-bed would show up. I did another nest change with the gourd empty. The whole bunch came back at around 18:00 and two young packed it up for the day and went into the gourd. One more came in around 19:15 after various aerial passes with the female. By bedtime, only three young were in the nest.

July 22 - The three left again at dawn, around 6:30 to return again between 19:10 and 19:20. No visitors found on the video. At 19:00, the female was perched on the antenna.

July 23 - Same routine today. An early morning departure at 6:45 and dusk return of the remaining three fledglings after 20:00.

This evening, we went down to Austin to see the dusk arrival of martins at the large roosting site. I assume that ours have not joined yet. I posted more pictures on a separate post.

July 24 - Normal morning departure of three young. Tonight, however, only two have come back by dark.

July 25 -  Another dawn departure of the remaining three. Stormy weather today and into the evening. At about 19:00, a female (ours?) was resting on the "L" gourd porch and poking her head in while a single fledgling had arrived and settled in for the night. On the other hand, we had over a dozen Chimney Swifts circling over the house for an hour.

July 26 - Another 6:30 departure of the lone resident. A quick scratch and stretch and it was out into the cloudy morning.

I was expecting them to be gone for good but, big surprise, this evening at 20:30 we have two in the nest again. I guess they come and they go.

July 27 - This evening, one fledgling came back at 19:40. It played with some of the straw for a bit and then left again at 20:10 and did not come back for the night.

July 28 - So, today marks our first "martin-free" day. No departures in the morning, no arrivals tonight.

July 29 - Again today, no sign of the tenants. They may finally all be headed to Brazil with a fine "so long and thanks for all the dragonflies."

July 30 - This morning, I cleaned out all of the gourds, getting rid of the straw and scrubbing them all out. I left the internal camera in place but put away the temporary external camera.

July 31 - A passing SY-male investigated the "K" gourd in the morning. This evening, we went back to the roost site in Austin for a final send off.

Aug 1 - I saw a pair of martins on the antenna in the morning but they did not land on the rack.

Aug 2 - These fledglings are killing me. I went back and looked at video coverage this evening and on the live feed found droppings in the gourd. Going back over the replays, I found that two fledglings had spent the night of Saturday 30th at the bottom of the now empty gourd. On the following two nights, one fledgling spent the night on the inner porch. It has not come back this evening. I feel really stupid for having cleaned it out prematurely.

Aug 3 - This evening, one of the young came back to the area, circling overhead and many times around the rack. It landed on the "A" gourd porch several times and peered in. It never entered ... naturally, since I had put back fresh straw.

Aug 4 - Repeat of yesterday. Danielle reported the young martin back on the rack today investigating "A" and "B". Again, it never went inside.