Nest Checks, New Hatchlings and Nets

My last nest check revealed I have 73 pair so far, with a total of 84 gourds offered.  I continue to be amazed at the resiliency of the purple martin, especially since the Great Horned Owl persists with her attacks.  As an added challenge this year, I've also had a problem now with the Barred Owl attacking my tree swallow and bluebird housing.
But for now, back to my GHO update.  On the morning of April 30th, I became quite alarmed to see the GHO has, after 3 years with these cages, now figured out how to get up and inside to perch on the inside arms of the rack.

After 2 days or mourning and feeling sorry for myself, I decided to cowgirl-up and my husband and I designed a "cargo net" style bottom which would balance the need of the purple martins to both exit quickly when a hawk attacked as well as serve to keep the GHO out. With the mandatory requirement of it being "quick release" so that I could continue with nest checks, we purchased some polypropylene rope, zip ties, quick release clips and some garden stakes.  The first 'net' picture you see below has 14x12" holes in it - I can always adjust the size of these holes if the owl gets through, but since the owl's wingspan ranges from 36"-60", I'm hoping I don't have to change these.  The 4 long ropes are crossed by 6 shorter ropes, tied together using zip ties at each crossing.

I've put together the video below to show other landlords how the netting is connected to the cages and how it quick releases for nest checks.  I made a mistake in the video - the rope is called, "polypropylene".  :)

For the round racks, a different approach was used to the the netting.

While the owl has definitely made my nest checks a little more time-consuming, my husband has always helped me come up with ideas to enable me to keep doing them. Given the heat & humidity we experience here in Missouri during the summer, it's imperative that I know the ages of the kids, because inevitably, I will have a few nestlings that will either get knocked off porches or they will jump and I need to know in which nest to put them back.
New "pinkies"!

Photo taken by my friend, Lu Ann Coons at her colony site here in Missouri.

It was very apparent the nest in the video below had just started hatching.  While it's tempting to help remove the shells from the little, adorable nestlings, because their skin is still so delicate and could be still attached to the shell, I never 'help'. I let Nature take its course - the baby will be stronger for it and I avoid damaging him/her.

The FOB - Part 3

When the weather warms, so do I.  With outside temperatures reaching 60 degrees this past weekend, I came down with "I-must-get-outside" fever and I finally put the finishing touches on my owl cage.  I am feeling so much better about this upcoming purple martin season, but I think I will refrain from my usual taunts that tempt fate such as, "Bring it on, Mr. Menacing-Evil-Martin-Eater".  You know, just in case he does decide to bring it on.  And something really bad happens.  So, I'll just nicely say, "please don't bring it on".
At a minimum, I know I have made it more difficult for him to easily access my systems and prevented him from playing volleyball with my gourds.  Hopefully, that will encourage him to hunt elsewhere.  Time will tell.
Altogether, I estimate we have added less than 30 pounds of hardware; that includes the fencing, the aluminum brackets that extend out over the corners, the cross brackets to support the top, and the entrance hole covers.
My plan right now is to lower the cage and maneuver inside for nest checks.  If that isn't realistic, I may have to cut off a foot of the vertical wire so I can more easily slide in & out of each section.

The cage will ride up and down with the system.  For now, I have left the full 4' of length on each side, but if maneuvering in and out becomes a problem, I may cut off at least 1' from the bottom. From this angle, you can see the brackets that span from corner to corner, providing both support and a place to anchor the top wire to keep it from flopping in the wind.

There are ten 4"x4" entrances cut out on each side and have undersill trim has been placed on the bottom of each entrance to cover up the sharp nibbins left by the wire cutters.

If you're interested in reading more details about the construction of the cage, you can go to these two posts:
The FOB - Part 1: http://kathyfreeze.blogspot.com/2014/11/the-freeze-owl-block-fob.html
The FOB - Part 2: http://kathyfreeze.blogspot.com/2014/11/the-fob-part-2.html
Current migration status shows that the purple martins are on their way with a report showing one in Saint Amant, LA.  Track their migration here on the PMCA site: http://www.purplemartin.org/scoutreport/

The FOB - Part 2

Now that I'm on vacation this week, the continuation of building the FOB has been my highest priority.  I do not want to wait until March and have to be doing this out in the snow!
As mentioned in my last post (http://kathyfreeze.blogspot.com/2014/11/the-freeze-owl-block-fob.html ), I had cut a couple of 18" arms to which I could test-mount the fencing.  It worked, so this past weekend, (and after sending Mr. Freeze back to the hardware store to get the right size nuts that I needed), I was able to cut and drill the rest of the arms and mount them to the gourd rack.
I then remounted all the gourd arms and made sure the nuts were tightened down so the arms would not rotate and allow the gourd to tilt downward.

The extra 18" angle arms are added to help extend and keep the fencing off the fronts of the gourds on the ends.  Holes drilled in the end of each 18" piece will be used to secure the fencing.

I then mounted the 6' aluminum angle arms between the main arms and carefully measured where I would drill the holes that would allow me to mount those without having to cut more metal, yet it would sit securely on the ends without slipping off.  Okay, I lied - I don't "measure carefully" unless Mr. Freeze insists that I need to.  And he said I didn't really need to, so I didn't.  I SWAGged it and it worked out.  I drilled a hole on each end of each arm and mounted them, butting one against the other.

The 4, 6' aluminum angle pieces are strapped down using zipties after drilling a hole in each end.  The pie-shaped top for this section was cut so that there would be no jagged edges.  They may overlap with the next piece a bit, but that's ok.  I'll also cut some 4"x4" holes in the top.

Right now, everything is secured using zip ties to ensure the design will work.  I haven't decided yet what the permanent solution will be.  I want to put this baby into practice and see what or if I will need to change something to accommodate my propensity to move quickly when doing nest checks while at the same time, not having to brush against mite-infested gourds.
I had been dreading facing two other challenges - figuring out how to get the maximum coverage from above without having to do a lot of cutting and what to use to cover the 'nibbins' when I cut out 4"x4" squares.  Today, the clouds parted and it all became clear.  Once I realized that I needed a 45 degree -pie-shaped section of fence and to do that, I needed to "cut two across, down one", I tossed the ruler, the square and the angle-thingy that Mr. Freeze gave me and started cutting.  I now have a roof over the top that will prevent the owl from dropping down inside the cage.  And I can secure it to the 6' angle arms, that I mounted earlier to keep it from floppin' around.

As for the covers of the nibbins in the newly cut 4"x4" openings, I have Mr. John Barrow to thank for that idea.  I am not ashamed to say that yes, I consult with a lot of friends to 'brainstorm' when I don't have a clue how to proceed.  John sent me some suggestions and armed with that information, I went to our local hardware store.  After the laughter died down from my trying to explain what I needed, they helped me find exactly the right material - easy to cut and cheap!  This trim is used to help start siding - commonly called "undersill trim".  I cut out a piece to try it and it snaps right on.  The best part is it doesn't try to rotate or pop off!  My hardware store sold me a 6' length for $2.50.  Yep, nothing like shopping "local"!  Thanks, John!

I have lots more cutting and some fine-tuning to do and I need another roll of the wire to finish, but basically, this is what my purple martins will return home to.  I'm only now starting to feel a lot better about their return next year.

The Freeze Owl Block (FOB)

Finally!  For a couple months now, the weather has been too hot to go out and start the cleanup of all the gourds and housing.  This past week has been much cooler and, feeling more secure that the mites and other creepy crawlies have drifted into their winter slumber, I ventured out to start the cleaning process.  With dirty gourds removed, Mr. Freeze is now more willing to help with the implementation of the new owl block whose plan has been changed countless times and under much discussion for months.
Mr. Freeze's 5 points of resistance were:
1. Wind.  Well, we do get lots of it here in Missouri.  My response was, the materials are lightweight and plenty of holes (ie, minimal surface area to catch wind).
2. Weight.  My response was again, the materials are lightweight and it's a 3" pole.
3. Our view.  We bought this property specifically because of its fantastic view to the south and who wants big cages permanently mounted in their direct line of sight?  My response, ok, we won't put them all the way up to the top, permanently mounted.  We can't really reach that high anyway.
4. Cost.  My response was, I've spent a lot of , ahem, a few bucks on these rigs to host purple martins and by comparison, it's not going to be that bad.
5. Why now?  Well, because Mr. Freeze, I don't want to go out in the February / March freezing temps and snow to try to measure & figure out the proper configuration for my racks.  Besides, you don't want to be out there then either, freezing off your wee knees right?
Thanks to Aprils Owl Guard pictures and a few emails back and forth with April, we were able to come up with a plan.  We found aluminum angle iron (36" long and 6' long pieces) at the local Lowe's store and the 2"x4" welded wire fencing (4' high) at our local farm store.
The 36" angle arm pieces were cut to 18" each then marked so they could be drilled to fit the already pre-drilled angle arms.  Since the angle arms are 1/8" thicker, we also purchased more bolts that were 1/8" longer to accommodate both the gourd arm, the original angle arm and the new one in the inner-most hole.  I thought we were being so smart to think of that.  But after drilling all the arms, I realized that I hadn't allowed enough room on the inside / underside of the new angle arm for the nut. So I had to move the small gourd arm to the outside and put the nut on the outside.  I can't think of a reason why that's bad...just aesthetically, it would have been better inside I guess.

2 pieces of fencing temporarily hung to ensure sizing is correct and the gourd won't be too close to the fencing.

The nut would not go on the inside as the hole was too close.  Every other vertical will be cut out to make 4"x4" openings.

Out at the opposite end of the arm, we drilled 2, 1/4" holes just in a bit from the end so that we can run #9 wire through the top and middle of the fencing to stiffen it, then bend the end of the wires downward so they can drop through these holes.  This will also allow me to remove the fence panels if needed during the season.

The #9 wire has not been weaved through the fencing yet.  Hung only temporary here to ensure proper sizing.

Right now, until I see how this is going to work in practice, I also plan to use the full height of the wire fencing - 4', hoping that will help discourage the owl from trying to fly up under it.  Once I wind the gourd rack down, I'll still be inside the cage and since I'm so short, I can move from section to section without removing the panels, unless I really need to.
I'll also be cutting out every other vertical wire to make the holes 4"x4".  I really wish I could find some pre-fabricated wire of that size that is made of this same light-weight material, but my searches have yielded nothing.

The 6' long piece of angle iron at the top will be used for support and to have something to which I can secure the top layer of fencing.

The 4' height of the fence may be too much, but I will leave it for now.

Lastly 4, 6' pieces of angle iron will be added across each set of arms at the top to support the welded wire fencing that will need to be spread across the top of the openings, so that my favorite Great Horned Owl can't just drop in for dinner from above.  Right now, there are no plans to enclose the bottom.  I'll monitor the rack and if he ever does decide to try to fly up into the cage, I'll deal with it then.  My preference though for now is to allow the martins an open bottom through which they can fly out and if the owl lands on top - which I'm sure he probably will - if they do panic & fly out, I don't want to find a bunch of birds hung up in the fencing in the morning.  Construction and ideas continue.  I will post more pictures as it develops.
(see Part 2 here: http://kathyfreeze.blogspot.com/2014/11/the-fob-part-2.html
see Part 3 here: http://kathyfreeze.blogspot.com/2015/01/the-fob-part-3.html)

The top will be enclosed with the fencing.  It will be secured to the 6' length of angle iron.

Playing Chess Instead of Checkers

Make no mistake over this writing - I am extremely distressed over this issue, but this is how I deal with my distress - I write to make myself feel better. When I was a small child, my grandfather taught me to play checkers.  As I matured, he taught me to play chess and it was obvious that chess required a lot more thought, planning and strategy in order to win.  I loved it, especially the knights and bishops pieces as their moves were the more complicated and aggressive on the board.  I never became a pro at the game, but I learned a lot from it that I now apply to real life.

If someone or something presents a smart move to you, make a smarter move in return.  That's the way I feel about my dealings with this owl.  I'm still not 100% sure, but believe my owl to be a Great Horned Owl - one of the most aggressive owls around.  In chess, the best games are played against a knowledgeable, respectable challenger.  Well, I think I have met quite a respectable foe in my current battle to protect my martins.  They don't call them "wise, old owls" for nothing.

Great Horned Owl image: National Geographic Online

From the All About Birds site:

Renowned for ferocity, Great Horned Owls kill and eat small to medium mammals of many kinds, especially hares and rabbits. They eat mice, rats, squirrels, opossums, woodchucks, bats, weasels, and the occasional domestic cat. Great-Horned Owls also eat skunks, which are sometimes such a prominent part of the diet that both bird and nest may smell of musk. Although mammalian prey typically comprise more than three quarters of the diet, more than fifty species of birds have been recorded as prey. In addition to hunting small songbirds, Great Horned Owls have been known to eat large birds such as grouse, herons, ducks, Canada Geese, hawks (including Red-tailed), and even other species of owl. A woodland with resident Great Horned Owls usually lacks any other raptors in the immediate vicinity.

Well, that may explain what has happened to some of the feral cats that have been roaming around here lately.  If I were an owl, I would prefer a larger return for the amount of effort required to hunt - a meal such as a cat or rabbit rather than a scrawny little songbird.  What is it about my purple martins that makes him want to come after them so aggressively anyway?  Do they taste like lobster or some other special delicacy?
My first moves in response to the owl were to put up the wire fencing around my Trendsetter and the array of garden stakes around my gourd racks.  We had multiple days where the owl did not make an appearance, then when he did show up, the game camera pictures showed him using the tops of the racks as perches from which he was hunting for ground-dwelling prey.

Then one night, he upped the ante - I found a bent garden stake in front of 2 gourds, which I replaced with an even thicker stake. As the stake he grabbed was just out of view of the game camera, I was unable to see what had happened, but I did verify that the martins in those 2 gourds were safe & still feeding their young.  In response to his move, I decided to stand watch and wait for him and hopefully give him a good scare.  He flew through my yard at 9:10 PM on 7/4, circled to some trees and at 9:25 PM, he returned to perch on the perching post, 20' from my martin housing.  I flipped on all the lights, including my million-watt spotlight and ran at him, screaming a lot of words that probably shouldn't be printed here on my blog.  Regardless, he left in a hurry.  Despite my feeling of victory in the battle that night, I knew that the war was not yet over, but I still hoped I had provided him with something to think about before he landed here again.
As most of you know, he upped the ante again on the nights of 7/7 and 7/9, challenging the integrity of my wire cage on the Trendsetter and flushing out several martins.
http://kathyfreeze.blogspot.com/2014/07/caught-in-act.html

While these videos have indeed been alarming to me, I saw his increased aggression as another challenge to which I needed to rise and hopefully, respond with something even better which will perplex and discourage him.  As of yesterday, we had 3 peaceful nights with no owl attacks, but knowing that he is probably not done with me or my martins yet., I built a scarecrow and christened her, "Ellie Mae" before sticking her out in the yard to stand guard duty last night.

As I sat with Ellie Mae in the yard last night, I saw a large bird with a large pair of wings silhouetted against the southern horizon moving steadily northward toward my colony.  "Holy Moley - he's bigger than I thought - not tonight - you will NOT eat martins tonight!", I thought.  Grabbing my spotlight as I rose and tensing in preparation to start my own running, screaming, scary attack, I stopped mid-step as my eyes identified my attacker - and I allowed the Great Blue Heron to pass, unmolested by my colorful words and lights.  I did find it odd though that after flying another 5 seconds north of my house, the heron suddenly turned 180 degrees, emitted her own alarm calls, and flew back southward.  What had scared her?  Had she spotted my owl perched in a tree north of the house and changed course?  I'll never know.
All the game cameras confirmed today that we have now been 4 nights without any night visitors.
Whether Ellie Mae is helping or not is yet to be determined.  I'll move her around the yard to different spots, keep playing the radio and keep the lights on all night.  If anything does happen, I'm sure I'll be dismayed, saddened, alarmed and very, very upset again.  But I will regroup and deal with it.
For now though; "Dear Mr. Owl - Your Move". 

The Night Belongs to Thee

I have been a busy purple martin landlord lately and not in a good way.  Between erecting owl guards and preparing for my presentation at the Missouri Department of Conservation in Houston, MO last week, I haven't had much time to write about it.  But now that the adrenaline is subsiding and the fear is alleviated with the installation of the guards, I now have some time to share.

Ever since mid April, I felt something was wrong in my colony.  I had found a Great Horned Owl feather in my driveway, but really wasn't too worried as it was over 200' from my colony and I wasn't seeing the classic signs that everyone talks about (plucked feathers, martins leaving the site right before it gets dark, etc.) 
 
What I was seeing were very few martins in my Trendsetter-12 house.  This was unusual because my oldest martins always took up residence in my Trendsetter first.  Afterall, it was my first *official* purple martin housing.  But something felt off and not quite right with my colony.  So, I ordered a Browning Recon game camera and put it out on April 21st.  Every day I would retrieve the SD card from the camera and find nothing recorded on it, except the daytime activities of the martins.
I got lazy and around May 3rd or 4th, I quit the daily retrieval of the card thinking that I was just being paranoid and silly and had read too many posts about owl attacks.  On Friday, May 9th, I decided that I really needed to check that card and I pulled it.  But I still didn't review its contents until just before bedtime that night.  As I opened the card and saw the timestamps on some of the pictures, my throat began to tighten.
Then as I started opening the pictures, I thought, "This can't be.  Everything was fine up until now, so why am I suddenly seeing timestamps for pictures at 4:23 A.M. for May 6th?"  As I viewed the pictures and my brain processed what had happened the night of May 6th (3 days prior), I felt something tighten around my waist and I couldn't swallow - I thought I was going to be sick.  I couldn't believe that a Great Horned Owl was attacking my housing.  The whole reason I had bought the Trendsetter was so that an owl can't reach into the cavity and pull martins out.  What he can do though as I was informed that night, was exactly what this Wise Old Owl was doing - he was beating his wings against the house, attempting to get the martins to flush, right into his talons.

Great Horned owl attack on my Trendsetter-12 housing.  Note the time. Dawnsinging starts about this time every morning at my colony, so it is likely that the owl heard the martins and was drawn to the housing.

The terror that had arrived at my colony on the morning of May 6th could have been enough to frighten the purple martins into abandoning that house.  And who could blame them?  I would certainly pack my stuff & go if I were them!  I wasn't as much worried about them abandoning though as I was about keeping the remaining ones safe.  I couldn't justify serving up a buffet to the owls.

I hastily made a post on the PMCA forum with the pictures and was rather surprised to see how many people were still awake and willing to help, advise and provide empathy at such a late hour.  I was willing to do whatever needed to be done to protect my colony.  It had been 3 days since that attack and there were no guards on any of the housing or gourds and there was no telling when he would be back.  I was frantic.  What if he came back that very night?  Was he successful on the night of May 6th?  I had no way of knowing.  Lots of good suggestions came rolling in, but there was only one reality - I needed to stay up and protect my colony that night and figure out how to get guards installed on all my housing the next day.
It was quite an experience staying up all night with my martin colony.  Owls hunt by sound and I can see why he was attracted to my colony.  My martins are noisy!!  By 3:30 A.M. the next morning, I could hear a Barred Owl on the east side of my colony and the Great Horned Owl (GHO) on the northwest side of my colony.  Hoot, hoot, hooting away.  I was happy as long as I could hear them calling, but when they became silent was when I became worried and started scanning my colony with my spotlight to make sure they weren't visiting.  Fortunately, they weren't.
I had always read that a GHO would displace a Barred owl, but as frequently happens here, my site is often the exception I guess.  By 4:30 A.M., I could hear my martins in the sky singing their dawnsong.  What an awesome experience.  It was a very strange feeling to hear martins in the black, velvety sky but only be able to see the stars.  I wouldn't trade that experience for anything.  It was one of the most beautiful things in the world.  Dawnsinging, the darkness of the night, stars and owls.  I have never felt more alive.
By Saturday afternoon, I had driven my husband crazy and we finally deployed the cage on my Trendsetter.

It took about an hour for my martins to adjust and trust it, but they finally did.  We used "Welded Wire Fabric", 2x4" from Orscheln's Farm Store and cut out a couple of wires to make 4x4" openings in front of each of the house entrances.  I have also added tubing over each of the entrances to make a more bulky landing spot for each of the martins.  I am happy to report that the house has martins and eggs in every cavity, except one.  That's a pretty good occupancy rate, given the circumstances.


By Sunday afternoon, we had erected some temporary guards on the gourd racks as well.  In thinking about how the owl had approached the housing and the wing span on the GHO (39 to 43 inches), the idea with these guards is to interrupt his wing space.  Pretty funny looking, eh?

I had always read about landlords erecting their owl guards and their martins seem to relax after installing them.  I thought, "how would you know"?  But now I have experienced it - you know.  Somehow you know, you feel it and you hear it in their song and see it in their activities.  They are safe and they know it.  Fortunately, the owl has not been back since that night.  I'm hoping it stays that way, but I'm no longer naive enough to believe that.
We are working on a plan for more permanent owl guards - something that won't interfere with our view during the off-martin season (can be removed), something that won't need a 20' ladder to install, something that won't interfere with storage, and will be user-friendly for nest checks.  My husband is brilliant and has come up with some ideas to fit our particular situation.
I am much more comfortable with knowing my martins are safe now.  But I have learned a few things.  First, trust your intuition and act on it.  And do it before something really bad occurs.  Apparently, we all live within the range of a barred owl or a GHO.  Don't get lazy.
Lastly, 3:30 A.M. is a special time with a purple martin colony, especially when dawnsinging starts.  It is wild; it was an ethereal experience and it is Mother Nature in her purest form.  I loved it.  I'll be up a few times every year now to enjoy it.  For that, I am thankful to the owl for the rude awakening.  I will remember you are out there always and you sir, YOU own the night.