June 30

     For those of you who have been following along, welcome to day 112 of the season. For those of you who are new to the blog, welcome to day 112 of the season :)  I have been seriously slacking on blog entries lately. There is just so much going on that by the time I enter data into the excel sheets every night it is after midnight.  I will attempt to give you all a synopsis of where things are at with the project. 

     Up until 10 days ago, there were 19 boxes where I had confirmed the presence of either eggs or young.  At this late point in the breeding cycle it is very unusual to encounter "new" boxes where so called "floaters" ( males/females that arrive very late in the season at boxes with the intent of beginning very late breeding) actually initiate successful breeding. Interestingly enough, within the last ten days I have discovered 2 more boxes where kestrels have just begun egg laying with a third box a strong possibility as well. That would bring the total number of successful boxes up to 22. I have boxes where the young left the box 10 days ago and now also have boxes with 3 eggs in them. That represents a 60-70 day window of breeding activity. That is similar to year's date ranges and has been a totally unexpected finding for this area.  To date there have been 34 nestlings banded with another 15-20 to be done in the next day or two. As pictured above, the nestlings are banded with both a metal federal leg band and colored plastic bands as well. The metal federal band has a unique number stamped into it that identifies every bird. Each nestbox has a unique color band pattern assigned to it that identifies the nestling's natal nestbox.  That unique color pattern is permanently assigned to every successful box. The only way to read the number stamped into the federal band is to recover the bird in your hand. The idea behind color banding is that in the future the color banded birds can be identified at a distance without the need for actually having them in your hand. It ideally increases the reporting of color banded birds in the usual instances where trapping is not possible. In reality, the color bands can be very difficult to detect in the field. It is had been moderately helpful to me in identifying birds not in the hand, but has resulted in no reports by other birders, etc. out on the field who might be seeing these birds. 

     This summer I also have a senior from the University of Connecticut who is doing her honors thesis work based on telemetry that is being carried out on some of the birds in the program. The basis of the telemetry work is to try and determine the post fledging dispersal patterns of the young. We really have no idea where the young disperse to once they leave the natal area.  Since the American kestrel is a threatened species in Connecticut, knowing where their critical stopover points are in migration and which corridors they may be using ( ex. the Connecticut River valley, etc.) when leaving their natal area is important information needed to help make informed decisions to aid in their recovery in the state. To date we have outfitted 4 nestlings with the tiny backpack radios. Our goal is to have 10 nestlings outfitted with radios.  Anything we learn about their movement once they begin leaving the natal area will be more than we know now..which is virtually nothing.  

This picture shows a 27 day old nestling with her radio backpack on. The only part visible is the thin antenna projecting out from the backpack. 

 An important step in the banding process is sexing the nestlings. That is most easily accomplished by examining the color of the primary feathers. The blue/gray coloration of these primary feathers identifies this bird as a male.

The brown coloration of the primaries on this bird identifies her as a female.  If the nestlings are younger than 14 days old it can very difficult to sex them since the primary feathers have not yet begun to emerge at that point. This female is approximately 18 days old. 

     The total number of box visits made by me so far this season is 948. Total miles traveled to date this season= 4,714. 

June 20

16 day old nestlings

Very fierce falcon wannabe 24 day old nestling

     a full box of 5 nestlings 20-24 days old with prey remains (song sparrow) left in the box by the adults

a close-up of the song sparrow left in the box by the adults

Annie and I with the first nestling this year to be outfitted with a radio transmitter for telemetry purposes

     After a little bit of a lull waiting for the young in the earlier boxes to develop enough to be banded, things are starting to pick up. Twenty-three nestlings have been banded to date. The broods have contained either 4 or 5 nestlings, which is the norm. You can see from the photos that the development of the young progresses very rapidly. The changes in appearance in the nestlings as they develop is remarkable. That is evident when you look at the photos of the nestlings above. The ideal age window for banding is 16-18 days old. If you remember from previous posts, this is calculated by dating forward from the appearance of the first eggs in the box. It is not always an exact science, but it can get you close. There are times when, for many reasons, one can be surprised upon opening the box. What you expect to be 16 day old nestlings looking at you can, in fact, be birds that are barely able to lift their head or birds that are nearly ready to jump out and join the big, bad world. Speaking of which...............I don't think I have mentioned this in other posts, but the expected mortality of first year birds is as high as 80%. Imagine thinking about the fact that, after all this work since March 8, probably only 1 out of every 5 nestlings will survive to breed next year. It is not something I tend to dwell on much. From the photos it is also obvious that the youngsters need a little help in the keeping their bedroom clean department. Actually, the center area of the box where they spend most of their time huddled is actually quite clean. Like many nesting raptors, these young are programmed from birth to back up to the outside edges of the nestbox and squirt their feces in an outward direction away from the center of the nest. This results in having the inside walls of active nestboxes completely covered with whitewash. One of my favorite jobs every March is opening the boxes to scrape off all the whitewash of the walls of the boxes. Ina howling, freezing wind it doesn't get any better than that. 

The prey delivered to the young consists mostly of insects, with the occasional meadow vole or small songbird tossed in for good measure. In my experience, it is the males who tend to deliver the largest prey items to the box. They don't show up often.......maybe once for every 40-50 visits by the female, but they deliver the goods when they do. The last picture today shows Annie and myself with a 28 day old male who has been outfitted with a radio transmitter for telemetry purposes. I don't have the time to discuss this topic now, but will cover the telemetry aspect of our work this year in a future post. I'm hoping to get to that post written fairly soon so I don't get chastised in Latin again for not posting more frequently :)         

June 7

An explanation of incubation timing, etc.

     Our vendor fair was a total washout today so we left to come early. I will take this opportunity to follow up on yesterday's post.  The typical clutch of kestrel eggs contains 4 or 5 eggs. Once the female begins laying she will lay, on average, one egg every other day until she is done. Once all the eggs are laid, it will be 30 days until the eggs hatch and then 30 more days for the young to fledge. This easy math makes the calculations for when banding should occur, etc. pretty easy to figure out.  The young should ideally be banded somewhere between the ages of 15-18 days old. At that age their lower leg bones are adult size so there are no concerns about their legs growing larger and having the bands becoming overly tight. In addition, beyond the age of 14 days old the primary wing feathers and other areas are developed enough to be able to accurately sex the birds. 

     Now, let's hit the rewind button a bit. The reason I spent so much time going into the nestboxes during April and early May was two-fold. First, it was necessary to keep the starlings out. Secondly, I was waiting to see the first eggs in the boxes so that I could then calculate the best day to go into the box to band the young. For example, let's say that on April 16th I went into a box and found 2 eggs. At that point I would add 2 days for every additional egg that would be laid up to a maximum of 5 eggs. That takes us to April 22nd. I would then add 30 days to bring us the the hatching date. That would be  May 22nd. I would then add 5 days to bring the young up to an assumed age of 5 days old. So after waiting 41 days from the time I found the first two eggs, I would go up into the box. At that point I would be able to fine tune the exact final banding date, wait for that date and band the young. The math is not as exact as I portray it to be in this post. Sometimes egg laying can be delayed, incubation times can vary, etc. but it's usually pretty close. If you band them too young, you may not be able to determine the gender of the bird. If you band them too old, you run the risk of having them leave the box too early and prematurely fledge. That puts them at very high risk.

     I hope this rather long-winded explanation helps others to understand the level of vigilance that is required if one is to to study and truly understand the dynamics of American kestrel populations. It is important to note that this is day 89 of my kestrel season and there is still a long way to go. Fascinating stuff.  In the next 10 days I will be doing pre-banding visits at many, many boxes. I will keep you posted on what I find.  

June 6, 2103

First young birds of the year :)

     Hello everybody- I'm sorry for the absence of recent posts, but this is a very busy season for my bird photography business.  My wife and I are leaving for vendor fairs that will run from tomorrow morning (Fri.) until Sunday evening. That, coupled with continuing long days in the field, have made it difficult for me to find the time for posting. I have confirmed eggs in 22 boxes. There may be another box or two that end up having eggs in them, but at this point in the season what you have now is probably what you will end up with. The starlings have been absolutely swarming some of the boxes that I had high hopes for so, for the first time since I have been running this project, I am actually closing those boxes up for the season. Above is a picture from yesterday that shows the young that were in the first box that had eggs this year. The typical clutch size for kestrels is 4-5 eggs.  There are four healthy young in this box, approximately 8-10 days old. If you look closely at the right front corner of the box, you will see an egg in the box that is obviously infertile. The adults have long since stopped incubation. 

     Timing is everything. I am now conducting what I call pre-banding box visits. The young should ideally be banded between the ages of 14-18 days old. At those ages their legs have reached adult size and the primary feathers have developed fully enough so that the birds can be accurately sexed. The question is- How do you know when they are at that age without being able to see them?  The only way to know is to go up into the box when you predict that they are 5-10 days old, have a look and then fine tune your final banding date from that. I will give a more detailed explanation of incubation/hatching/banding timing in my next post. I've got to run now, but there will be more posts coming as soon as I can find the time. 

May 20

The Dance Still Goes On........

     I sometimes think of this period in the season as "the dance". It kind of reminds me of all the drama that used to surround a high school dance. You know...stuff like "Who is going with who?", Where did those two disappear to?", "Are those two REALLY serious or is it just for show?"  You know, that kind of thing. I now have eggs confirmed in 20 boxes, but there are still quite a few that are still a toss up as to what will happen. Just in the last two days I have had single males arrive at boxes that haven't shown any kestrel activity since early April. Whether they find a mate and stay at these boxes is anybody's guess. One interesting fact is that between the 3 boxes that are just now getting some kestrel attention there have been a total of 28 starlings removed from them. This is just the kind of unpredictability that keeps me going. After removing 14 starlings from one of these boxes over the last two plus months you would think I would just take the box down. Then, lo and behold, a male shows up. Go figure. 

     I now have eggs in 7 boxes which are in their first year of the project (they were put up last Oct./Nov) but also have had no activity at all in 7 boxes which have been historically very successful boxes year after year. I am at a complete loss at to why this is happening. 

     Also of note is the fact that the first eggs laid this season will be hatching in about 15 days, yet I still have a number of boxes with paired birds who have not begun laying eggs and other boxes with single birds that haven't even found mates yet. Some of these late starters won't have young hatching until early August. That confirms my finding from last year that the window for egg laying in my project area can be up to two months long-or longer. 

     This is day 73 of monitoring for me. It definitely becomes increasingly difficult over time to get that ladder off the car and climb up to set yet another starling trap, but I have too much invested time-wise now to just stop. Due to the cold weather delay this spring, this season is turning out to be especially long and drawn out, but if this was easy everyone would be doing it. I was hoping for 30 boxes with eggs this year, but it is obvious now that I will fall short of that goal. That's OK. 

      Some stats:

-number of starlings eliminated to date= 81

-number of miles traveled to date= 3,476

-number of box visits= 802

-number of boxes with eggs= 20

-of 46 adults banded so far this year, the number who were originally nestlings from this project= 1

-this is day 73 of monitoring boxes for this season

May 11

Happy Mother's Day Eve

     Why start a kestrel post with Happy Mother's Day?  I think it is fitting to do that because I have not yet mentioned a very, very important partner in my kestrel work and that is my wife Janet. It has now been slightly over two months since I began the nestbox monitoring for this season.  During that time I have spent 46 of those days entirely in the field from sunrise until dark closely monitoring the boxes in my project. This is at the height of spring's renewal when there is so much to be done around the house and in the yard as the weather slowly warms up.  During these last two months my wife has stacked our firewood, hauled and stacked mounds of brush, done all the lawn mowing, turned over and planted many of the gardens, run the leaf blower for hours on end, brought up all the deck furniture from the basement, etc., etc., etc. and never once uttered a complaint about my near total absence while all this was going on. Every night when I got home, she would ask all about my day and inquire about which boxes, etc. I would be checking tomorrow. Only Janet can fully appreciate the joys and heartbreak that I have encountered during these last two months. Without her patience and understanding, there would be no Northeast Connecticut Kestrel Project. There would just be dozens of kestrel boxes filled with fat, happy starlings.  I cannot begin to thank her enough for her patience and support.......and I am far from done. It will be at least another 3 weeks of very intense monitoring before I can be certain of which boxes will have eggs and be on their way to producing healthy nestlings.  There is still lots (hopefully) of nestling banding on the horizon as well as the telemetry study that I will be collaborating on with the University of Connecticut. That study will involve harnessing 10 nestlings in  my project area with tiny transmitters a day or two before they fledge. There will be much more to come on that work as it unfolds. 

     By the middle of next week I should I have a fairly accurate count of which boxes have eggs. Until then I am working hard to keep 9 boxes starling free that MIGHT end up occupied by roaming, unattached kestrels that are in my area (we call them "floaters"). I am definitely running out of time though. With some boxes already having full clutches of five eggs, it is obvious that the vast majority of kestrels who will be setting up shop in my project area have already done so. We'll all have a clearer picture of where things stand a week from now.  

May 6

A Tale of Two Boxes

    To illustrate just how unpredictable and resilient the American kestrel can be, I thought I would share with you the story of two of the boxes in my project to date.  

     The first box is brand new this year (put up last November before the ground froze). It was put up with a second box in a very promising section of habitat which consisted of mostly evergreen nursery stock mixed with some patches of barren, weedy ground-perfect.  Early in March there were kestrels present off and on at the farm, but it was obvious that they were just moving through. I saw my first kestrel in the vicinity of the box, a male, on 4/12. Up to that point, I had removed only 1 starling so I thought things were looking up. Unfortunately, soon after 4/12 the starlings really began showing an interest in the box. From that point on, I began eliminating starlings about every other day with no sightings of kestrels near the box. When I arrived on the morning of 4/27, I was shocked to see 3 large farm tractors, one tractor trailer, 2 large irrigation rigs and about 12 farmhands all working within 15 feet of the box. This went on for days. Amazingly enough, there was a starling peeking his head out of the box when I showed up later that day so I dealt with him (he was the 7th starling that had been removed from that box), but at this point I had totally written off the box, after 45 days of persistence, as a failure for the season. Six days later, on 5/3, I showed up after the farmhands had left. All the equipment was still there. There were no signs of starlings or any other avian activity. Just out of habit, I figured I should go into the box just to see what was going on. When I opened the box I was looking at two kestrel eggs. I almost fell off the ladder. At some point in the previous 5 days the kestrels had adopted the box, despite all the craziness around it and laid 2 eggs. Unbelievable. 

    The second box was in a very similar area of habitat in the town of Ellington. Unlike box #1, this box had almost no starling issues all season long and was being regularly visited by the a pair of kestrels since 4/8. One day I ran into the farmer who informed me that a "little wood cutting" was being done on that parcel and he hoped that it wouldn't bother the kestrels at the box. A couple of days later I stopped over to check out the situation. Within 25 feet of the box there were 2 enormous wood skidders dragging whole trees and brush to a 300 HP chipper that could take trees up to 23 inches in diameter. They were being fed into the chipper by a huge excavator. There were three tractor trailers waiting to be loaded with chips that were lined up wheel to wheel within 10 feet of the box. The "little wood cutting" turned out to be 30 acre clearcut. This went on for four full days. It is hard to put into words what I felt after seeing that 47 days into my kestrel season. After all the equipment was finally moved out, I looked in the box and saw that the kestrels had obviously abandoned it. Two days later a starling was peeking out so I took care of him. Two days ago I visited the box and saw no activity at all. Determined not to repeat my rookie mistakes from the past, I took NOTHING for granted and went into the box. After I lowered it, I looked inside and saw a female kestrel crouched in the corner looking back at me. It remains to be seen if she will stay and lay eggs there, but it was a very, very emotional moment for me. What amazing birds. 

      Total miles driven this season to date= 3,011   Total number of box visits to date= 704.

     

April 30

     First eggs of the 2013 season!! Pictured above are the first kestrel eggs I have seen this year.  I decided that starting today I had to make another swing through and check the inside of every single box in my project, regardless of what I THOUGHT was going on with any one particular box. I have been "missing in action" for the last three days because I had to attend an artists' fair where I was displaying/selling my bird photography. Most readers of this blog are probably not aware that in addition to being a kestrel researcher I am also a professional bird photographer (www.onthewingbirdphotography.com) 

     Sooooooo......what price did I pay for taking three days off from nestbox monitoring? How about the first 9 boxes I checked yesterday (Monday) had starlings in them! All of those boxes were starling free on Friday. By Monday they all had starling nest material in them with two of them actually having starling eggs in them to boot. On my rounds today I also discovered that I have been guilty in the last couple of weeks of making a real rookie mistake. I had four boxes where, for the last 10 days or so, I have regularly seen pairs pf kestrels either on or around the boxes. At these particular boxes, there has been absolutely no outward evidence of starlings using them. As I said earlier, there are certain times during any kestrel season where it is imperative to actually go up into each and every box in my project to accurately assess what is going on. When I did so today, I discovered starling nests, some with multiple eggs, in every single one of those four boxes. I had mistakenly assumed that the kestrels had "adopted" the box (therefore no need to check any further) when, in fact, the kestrels had either been migrants who were using the boxes as hunting platforms or were birds interested in adopting the box, but discouraged from doing so because of the starling presence at them.  Not once in the last 5 or 6 visits had I detected any outward signs of starling activity. The kestrels have now left all those boxes and I can probably chalk those boxes up as failures for this year. The window for new birds moving is rapidly closing. NEVER assume anything when working with kestrels. 

     On a brighter note, of the 31 boxes I checked today, five had eggs (one with 5 eggs in it) and many more showed positive signs of imminent egg laying. I hesitate to give actual numbers at this point.  Very soon I will be revising my previous estimate of active boxes downward by quite a bit. Many previously active boxes now appear to have been abandoned, but this is a very tricky part of the season to figure out, so we'll have to wait and see.   

     More on this tomorrow. I've got lots of data entry that I have to get to before I fall asleep at this keyboard.

     

April 24

Better to be safe than sorry...............

     A couple of weeks ago I was parked alongside the road with my binoculars out checking a nestbox in a neighboring field. Out of my rearview mirror I noticed a local town police car come up behind me very slowly and proceed to go past me very, very slowly. For a couple of years now I have thought about the attention I must drawing to myself as I repeatedly drive slowly past houses with my binoculars, spotting scope and/or camera out-often stopping near houses to gain the best view of a particular box that I don't have field access to. The fact that my car has no exhaust system (got ripped off in a cornfield 3 weeks ago), is usually covered with either mud or cow manure, and the occupant, after 10 hours of checking boxes, can look more than a little sketchy got me to thinking that I should take some measures to identify myself to help allay any suspicions that might be out there about my behavior.  Now each side door has the magnet sign that you see pictured above. I also will be going in person to the police departments in every town that I work in to identify myself, give them my license plate number, and a description of the car.  I don't take this lightly. In this day and age, I can certainly understand why there might be questions about who I am and what I am up to. 

     It has now been 46 days since I officially started checking boxes for the 2013 season. The next 2 weeks are probably the biggest roller coaster ride that a kestrel researcher goes  through all season.  Boxes that have had absolutely no sign of kestrel activity end up having kestrel eggs in them while other boxes that have shown the repeated presence of pairs of kestrels for a week or more end up, for some unknown reason, to be abandoned ( I have never had them abandoned with eggs in them).  New boxes that might have been erected only a week or two ago now have kestrels sitting on top of them while boxes that have been successful for two or three or four years running have no birds interested this year (yet...............)  Go figure. All bets are off until you finally see eggs in any given box. We're getting there, but I haven't seen any eggs yet.

     Since I started on March 8 I have done 608 box visits.   Total miles traveled so far this season= 2,512. 

April 22

End of Another Great Day Afield

     

     I took this photo at the end of another 12 hour day yesterday. The moon was beautiful. The starlings are now very driven to find boxes and get the nesting process underway. Keeping the boxes clear of starlings for the next 10-14 days is going to be increasingly time-consuming. I think I set a new record yesterday and today by eliminating 10 starlings. The box pictured above had 3 starlings eliminated from it in one day. As soon as one was eliminated, another one would move in within the hour. I deal with this by setting a starling trap, continuing on my circuit, and then circling back at regular intervals to see if the trap has been sprung. Most of the boxes that are going to be successful now have paired kestrels at them, but to help ensure that some remaining empty boxes become populated with kestrels it is imperative that starlings be kept at bay. At three different boxes today, I had starlings looking out of the nestboxes with kestrels perched not more than 50 yards away indicating that they were interested, but apparently unwilling to evict the occupants themselves. On 2 different occasions I have seen kestrels kill starlings in the vicinity of boxes, but my experience is that this is rare. The kestrels generally prefer to just move on. 

     Following is some data from this season to demonstrate that this is not simply paranoia on my part. 

     Aborn Farm Box

     4/1  starling eliminated

     4/7  starling eliminated

     4/13 starling eliminated

      4/16  male kestrel at box

        4/18  female kestrel at box

         4/20   pair of kestrels at box

Laughlin Road  west box

4/17   starling eliminated

4/18   starling eliminated

4/20   starling eliminated

    4/21   pair of kestrels at box

     Would these boxes ended up having kestrels using them if I had not intervened at all with the starlings? My answer, based on my experience, is a resounding no. I do realize that there are researchers out there who feel that these situations need to be left alone to run their course to see if, in fact, the starlings do successfully outcompete kestrels for available nestboxes. I am not inclined to allow nature to run its course every season in these types of situations. Left unmanaged, these boxes would just have been starling factories. With kestrels threatened in Connecticut and in steep decline elsewhere in the Northeast, I am unwilling let the starlings have their way.

     

           

April 19

First Egg of the Season........Sort of

     We are about one month into the season now and things are running about 2-3 weeks behind last year.  Last year at this time 14 boxes already had kestrel eggs in them. So far this year I have not found one single kestrel egg in any of the boxes. I have been into over 40 boxes in the last two days so I have not checked them all (63 total boxes) but so far no kestrel eggs.  I did, however, find my first starling egg (pictured above) in a box today. I usually stay ahead of the starlings and never let things get to this stage, but this box never showed any evidence of starling use so I left it alone. This is a perfect example of why it is so important to periodically go into all boxes to assess what is actually going on. During my latest rounds of box checks I have found 31 boxes with well formed "cups" or depressions in the shavings which is a very good sign. Not all of those will probably end up with eggs, but a very high percentage will.  There are still about 5 or 6 boxes with no cups formed that are historically successful boxes so we'll see how this all shakes out.

     Total number of box checks to date = 507     Total miles traveled so far = 2,087

     

April 16

     Well, we are about one month in to the season now. Every year I arbitrarily designate the "beginning" of the season as March 15.  At this point in the season, some boxes have pairs at this time that have actually begun laying eggs while other boxes have not shown evidence of any kestrels visiting them at all.  Up until now, most of my box visits have consisted mainly of binocular views from a distance looking for the presence of either starlings or kestrels on, in, or near the boxes. 

     After a month of no discernible activity at some boxes, it is now important that I actually climb the ladder and go into all of those "dead" boxes to see if there are any clues inside as to whether they have actually had any visitors or not. This is very, very time-consuming, but necessary. Today's box visits represent the entire gamut of what you might find when looking into boxes that appear to have had no visitors.  One "dead" box I visited today was full of grass and typical starling nesting material. I had never seen starlings at this box, but they obviously had entered the box and spent time there. I dumped everything out, refilled the box with shavings and moved on. Another box was completely untouched with the shavings looking as pristine as the day I put them in there. Another box had a well defined depression in the center of the shavings. I call this depression a cup. The presence of a cup-shaped depression in the center of the shavings is a sure sign that kestrels have entered the box and begun preparing the shavings for egg laying. I had never seen a kestrel anywhere near this box in the last month, but the signs were definitely there. It is actually not that surprising if you think about it. I only spend perhaps 10 minutes every other day watching any particular box. Given that there are 12 hours of daylight every day it is easy to see how their movements can go unnoticed by me during my rounds.

      The next 4 or 5 days will be spent going into every box that has shown no apparent activity. The birds are still moving into the area, so this becomes a very active, interesting time of the year for kestrel nestbox managers.

April 14

     There was a very significant push of kestrels through my area today which, given the fairly strong NNW wind that developed this afternoon, was a bit of a surprise to me. I always expect to see larger numbers of birds passing through when  the winds are favorable from the S or SW.  Today I got to thinking that perhaps the NNW winds don't necessarily encourage the birds to move through but, rather, holds them up a bit, concentrating them over prime food sources and making them more visible.  Today I had at least 6 kestrels hover hunting in one 15 acre parcel off of Middle Road in Ellington for most of the afternoon. 

     Since my last post, I have trapped 4 more birds, none of which were banded. It is interesting to me that 2 weeks earlier there was a higher percentage of recaptured birds that were previously banded locally. For the last five days or so, all of the birds trapped were unbanded. This seems to suggest that local breeders MIGHT (I emphasize MIGHT) move into my study area earlier than other migrants. The strike against this possibility is that if these recent migrants are still moving on, one would think that since they have to cover more ground to get to breeding areas north of here, they would have had to get an earlier start-making them among the very first captured birds. There is so much we just don't know. My sample size is way too small to make any decisive judgements on this, but it will be something I will be watching closely as we accumulate more data over the years. 

     The other trend I have noticed this season is that active starling investigation of the kestrel boxes has, until the last three days or so, been way behind last year's pace. In the last three days there has been a noticeable increase in the number of starlings occupying boxes, but overall it is much, much less than last year at this date. So far this year I have  eliminated 13 starlings. Last year at this time the number was over 40.  

     For those of you who have been following along, you probably have some sense of just how much time this takes if you want to do more than just produce more kestrels.  My daughter Jennifer, an Excel whiz, has been a huge help to me this year. I now have a very large spreadsheet that is allowing me to much more easily track what is going on. The flip side of that is my last 4 year's excel sheets were very poorly designed. Every night I try to spend at least an hour re-entering data from the last 4 years into the new format. So, a typical day involves being out in the field 10-12 hours a day, coming home and entering all the data from 20-45 box visits (plus trapping data) for the day and then working on the previous year's data to make it more accessible. Oh yeah......trying to keep up with my journal (blog) entries as well.  

    Miles traveled this season =1,669   Number of box visits to date this season = 431

     

April 11

       Kestrels are continuing to move into the project area at a steady pace.  There are now kestrels in the vicinity of 24 nestboxes.  The conventional wisdom with nestbox proximity has often been to place the nestboxes no closer than 1/2 mile to existing nestboxes. When I find a promising large ( 30+ acres) area of prime contiguous kestrel habitat I often like to put up 2 boxes in that area to give the birds a "choice" if/when they begin exploring the site. Last year, purely by happenstance, I actually had 2 boxes that were a mere 300 yards apart both have kestrels successfully breed in them. This lead me to pursue what I now call my practice of saturation. I have now started adding second, and even third boxes, to large areas of prime habitat that have had kestrels successfully breeding there in the past. 

     My practice of saturation was validated again today when I spied a male kestrel on top of a box in the same field where there is already a pair of kestrels established at a different box in the same field. It remains to be seen if that second male will be joined by a female, but it is an interesting observation nonetheless. 

This picture shows 2 successful boxes from last year 297 yards apart.   

This picture below shows the 2 boxes I observed today. They are 325 yards apart. The north box has a pair at it and the south box was where the male was seen today.

The picture below shows the most extreme example of saturation that I have attempted to date. I have observed birds at box boxes this spring, but it currently impossible to tell if there are actually two different pairs at work here. In a couple of weeks I will be going in to the boxes to do an egg check. That will tell the story. These boxes are 149 yards apart.

    If I continue to have success with this practice of saturation it could have significant implication for other kestrel researchers out there who are keeping their boxes 1/2 mile, or further, apart. We'll see. 

April 9

     The above picture shows you what kestrel eggs look like. No.......this picture was not taken this year, but quite soon I should be able to post a picture of the first eggs laid this season. One thing I have learned from this project is that the window for nesting and egg laying is much wider than many originally thought. The graph below (the yellow text is hard to read, but I'm too lazy to fix it...long day) shows the range of egg laying dates last year. The window was nearly 2 months long. So while a box or two probably now have eggs in them, many boxes have not even seen any birds yet. The typical clutch size is 4-5 eggs.

     Some facts to date. 15 adults have been trapped, 7 of which were recaptures. At some point I will summarize all the recapture data, but that won't be until late summer. As of today, 20 boxes have had birds in the vicinity-some pairs, some not, but it is important to note that this does NOT mean that all 20 of those boxes will have breeding birds in them when all is said and done. Good sign though. There are still many historically "good" boxes that haven't had birds at them yet. I find it very interesting that so far this season only 11 starlings have been eliminated. Last year at this time, over 40 had been eliminated. I have some ideas on this, but that will be a topic for later in the season when the starlings are no longer a factor. Miles traveled to date=1,447   Number of box visits=363

April 7

     Surprise, surprise!!  With almost 60 boxes to check and clean out every year you are bound to have a surprise encounter every now and then. Usually it is just field mice or squirrels but last winter, while taking a box down in South Windsor, I found this gray screech owl staring back at me when I opened the box up to clean it out. He allowed me to reach in and gently pick him up and seemed pretty content to just look around before finally flying off. 

     Today the wind changed direction from NNW to S (finally!!) and, as expected, it resulted in me seeing quite a few kestrels moving through my study area today. From their behaviour it was obvious that most were simply migrating through, but I was able to capture three birds, two of which had been previously banded in my project area. One was banded as an adult in 2012 about 4 miles from where I saw her today. Another one was banded as a nestling in 2011 at a box that is 19 miles away. The third bird was banded with a federal band, but the band was never registered with the Bird Banding Laboratory so I will have to contact them to find out the original banding location of that bird. It was definitely not banded at any time during my years on this project. The information that I am getting from the recapture of these banded birds is extremely important. Never before did I have any idea of the origin of the birds that would show up every spring at the boxes. Over time we will learn a great deal about how many local birds return, what percentage of birds that return were originally project nestlings, and what percentage of returning birds are from somewhere out of the project area. It will also be interesting to see if there are patterns of nesting returns and site fidelity that are gender based as well as patterns that may be age class based. All good stuff. 

     Total miles traveled so far this season=1299.  Total  number of box visits to date=308.

     

April 5

     We are now entering the part of the kestrel season which I find to be the most confusing and stressful. It is always very exciting to see the first kestrels of the season beginning in mid- March.  The expectation is that as the weather warms up one would see a steadily increasing number of kestrels showing up at various boxes, but that doesn't appear to be the way it works. As the weather warms, there are times when the boxes that had kestrels very early on appear to have been completely abandoned. We are now in the period where the boxes that have been successful for the last five years appear to have absolutely no kestrel activity whatsoever. In the past this has gone on for a week or two and then suddenly, within the course of 2-3 days, there are kestrels everywhere. It is the waiting right now that is so difficult. Could this be the year when it all suddenly falls apart? Maybe. We'll have the answer to that in a couple of weeks. Right now my number one job is to keep the boxes starling free so when the kestrels do show up there will be no starlings using the boxes. By this time last year I had removed almost 30 starlings. This year so far I have removed only 5. There are any number of possible reasons for this, the most obvious being that the cold spring has pushed everything back-including the arrival of kestrels. We'll see.

     I did have one adult female capture yesterday. She was unbanded. Her weight was 133 grams which is pretty robust for this time of the year. Birds banded at this time of the year that are on the heavy side could possibly be migrants just passing through on their way to breeding farther north. There is a principle called Bergmann's rule  which postulates that species that spend most of their time in colder climates to the north tend to be heavier.  This added mass is thought to help them conserve body heat more efficiently. So far this season, the trapped birds that have been wearing bands indicating they were banded within my study area have been averaging 10-20 grams lighter than the unbanded female that was banded yesterday. It will be interesting to see if the heavier bird banded yesterday does, in fact, remain in this area to breed.  

April 3

     This post will cover both today's and yesterday's activities.  The combined mileage for both days is 266 miles with 66 combined box visits. I thought that the continued very strong NNW winds would be holding up the birds south of us, but there was actually pretty decent numbers of birds showing up-especially today. When the temps really warm up mid-week next week we could be in for quite a push. There are now pairs at 7 boxes with an additional 5 boxes showing single birds in the area. It was always my belief, from the reading I have done, that the males show up first to begin establishing territories with the females showing up 2-3 weeks later. So far that is not the case in my study area. To date I have seen 8 females and 4 males at various box locations. I don't know what that means, but it bears watching as the season progresses. 

     The trapping of adults to date has begun to yield some very important information about site fidelity and the process of box selection early on. One female banded as an adult from the Depot Road box last year has been caught twice already this season at two different box locations. Once at East Road North and once at the Grant Farm. Both of this year's locations are approximately 8/10ths of a mile from the original capture site last year. The female captured today at the Middle Road pole box was, in fact, captured and banded at that very same box last spring. It will be interesting to see if she jumps around or stays put and breeds at the Middle Road box. In the past two days two additional unbanded females have been caught as well as one unbanded male. They are now wearing jewelry and will hopefully provide us information in the future.

      I'm sure you are all wondering what the photo is at the top of this post. Starlings are the major NUMBER ONE problem in my study area when it comes to factors affecting kestrel nestbox success. Even though kestrels are in the mighty falcon family of raptors, they are very wimpy when it comes to ousting starlings from nestboxes. Starlings are very, very numerous in my area and are very aggressive cavity nesters. My number one responsibility for these next 6 weeks is to keep starlings out of the boxes to provide open windows of opportunity for the kestrels to move in. Once the kestrels "adopt" a box, the starlings do not come near it. In the early years of my project, I would merely climb the ladder, scare the starlings out of the box, close it up and hope for the best. It didn't take long to realize that before I even got back to the car, the starlings were often already back in the box. Permanently removing them was the only solution that would work. Since they are not a native species, it is legal to euthanize starlings. The bigger problem was catching them. Above is a trap devised by an elderly gentleman in Iowa that is the only thing I found that would work. The trap in the photo is in the set position. The starlings can not see it from the outside of the box. As they enter the hole, they trip the metal wire you see sticking out which slams the folded back metal plate up against the hole, blocking their way out of the box. After that, they are dealt with accordingly.

     Total miles to date=1020   Total box visits to date= 222

April 2, 2013

On the Road Again..............

     This picture shows my 1996 Subaru (262,000 miles) loaded and ready for a day in the fields. Traveled 121 miles today and checked exactly 40 boxes. Two starlings eliminated today. There are now 10 boxes with kestrels in the immediate area, but it is important to point out that does not necessarily mean that the birds sighted now will remain at those boxes and breed. There will be lots of shuffling, disappearances for a week or so, etc. before things finally settle out. The best indicator that a box is going to have breeding birds at it is when you repeatedly see pairs at or around the box. Currently there are 3 boxes with pairs at them. 

    Nestlings have been banded in my program for the last four years, but the problem with banded nestlings is that they have a very high mortality rate-reported to be 60%, 70%, or even higher- and they also have a very low degree of natal site fidelity. The last term refers to the fact that the following year they don't often return to the area where they were raised. These two factors mean that banded nestlings don't often provide very much in the way of hard data when trying to assess return rates, survival rates, etc. Breeding adults, on the other hand, are thought to more regularly return to their previous year's breeding area (maybe not the same box, however). It was with this thought in mind that I began seriously banding adults for the first time last year. I was hoping that by doing this I could shed some light on the very thorny problem of trying to figure out just who is sitting on the top of that box come March.

     Today I was able to capture two adult females and was very pleased to see that the data I was hoping to collect has begun to trickle in. Since this blog is also serving as my personal  journal for the year, I need to be using specific box locations when discussing various situations as they arise. This is not helpful to you, the reader, but is very helpful to my research. Sorry about that. At the Lipton Farm south box I captured a female that was unbanded. Since I did band the adult female that used that box last year, I at least now know that the bird currently at that box is not the same female as last year. The second female kestrel I captured was at the Grant Farm in East Windsor. Interestingly, she was the breeding female last year at a box that is 1.2 miles south of the box where I caught her today. So far, neither female is the same bird who used their respective boxes last year. Good information. Total miles traveled to date=744   total box visits to date=156

April 1, 2013

     Today I checked 9 boxes. For the purpose of this blog, "checking" a box or "visiting"a box could mean anything from viewing the box at a distance through binoculars for 3-5 minutes to actually lowering the box to inspect the inside for eggs, young, or to set a starling trap. One female seen on a box in Mansfield and one starling trap set in Mansfield. I also removed a box that has been located at a local vineyard for the last four years. This box was a classic example of mistaking migrant kestrels that routinely appear at certain locations and then move on for birds that appear to be interested in stopping locally and breeding.  Coastal locations in CT are other good examples of this. Out of the four years the box was up at the vineyard, there was one year where there was breeding, but over 30 starlings were removed from the box over the years with no other evidence of kestrel breeding - despite the presence of male and female kestrels every spring during the late March-mid April period. With statistics like that, I have finally learned that it is better to just pull the plug, no matter how great the potential appears to be. 

    I also erected a new box at a local Christmas tree farm that has limited habitat that is completely surrounded by woodlands, but it is a tree farm and kestrels love tree farms. This time next year, it may join the ranks of over 100 other boxes that have been removed after their honeymoon period is over. 623 miles traveled this season so far.

Saturday, March 31, 2013 

     This is my first blog post.  The last thing in the world I ever thought I would be doing was starting a blog, but there has been increasing interest in my kestrel nestbox project over the last few years so I thought instead of clogging up people's inboxes with emailed updates, I would create this blog that would give anyone who might be interested in what is going on a place to go to find out what is happening with my project. I plan on creating entries after every day that I am afield which means that many times these entries will be on a nearly daily basis. 

This first post will be on the long side because it will summarize what has happened since I began monitoring the boxes on March 8. 

     In the fall I removed 13 boxes that were proving to be unproductive over the last few years. At that time I also erected 15 boxes at some new, promising sites. With the 3 new boxes that I have also erected this spring, the total number of boxes now stands at 57. This spring has been much colder than last spring and some of the early data this spring seems to indicate that the arrival of kestrels to the study area, and the nestbox investigation by resident starlings, is heavily influenced by temperature. By this date last spring 19 boxes had either single or paired kestrels in the immediate vicinity. So far this spring 3 boxes have had kestrels in the vicinity. By this date last spring I had eliminated 20 starlings from nestboxes. So far this spring I have eliminated 1 starling from nestboxes. This spring's numbers are also probably artificially low because I have not visited all 57 boxes with the same frequency as last year. The installation of predator baffles on 45 of the boxes this spring has taken up a great deal of time so overall box check visits are down. From tomorrow on,  I should be able to visit many more boxes per day. Total miles traveled this season to date is 527.  As an aside, I have totally messed up my profile and have no idea how to fix it so you can pretty much ignore that until I figure out how to edit it.