Thirty years ago I started at this site. I think it¡¯s a good Purple Martin site with 1-¨ö acres of land with a one-story ranch home on center. Nine Purple Martin houses are located 75¡¯ to the back of the house and there is another 85 feet from the Purple Martin houses back to deep woods with high mature trees. There are perfect open (no trees) flyways to the left and right of the colony site, as well as a good flyway over my ranch home. In fact, about 60% of the martin flights are made over my homes, even though this does make for some white spotting of the house siding and bay windows. Some entrance flights are made from the high woods in back, but exit flights are very rare because of the short 85-feet distance to gain altitude. A small river runs through the high woods about 1000-feet from the site. I still think it¡¯s a near perfect site to start a PM colony as compared with others I¡¯ve seen through the years.
Despite all this, I still waited seven years for my first Purple Martins to nest and raise families. In Year 7, three pair came on the last weekend in May. They arrived at a point where I had almost given up for another year. Fourteen young were successfully fledged that year. Those were the days when very little information was available about how to care for a PM colony. I was no longer a wannabe. I was elated.
Year 8 brought 10 pairs, then 21, 32, 41 and 50 pairs in Year 12. Now, I was a Purple Martin landlord for sure! I had all of the usual problems; sparrows, starlings, raccoons, nest infestation, hot and cold weather, and an occasional owl¦¡just to name a few. By now, I was trading information with a few other landlords that I had met, and together, we invented solutions to common problems. The site now had nine home-build wooden houses containing 124 nesting cavities, all having 1-7/8" hole sizes. All cavities had offset (to the side) entrance holes, and as new predation information became available, compartment lengths varied between 6" and 11". Aluminum houses were also tried as the colony grew, but very few martin pairs would accept them when offered the choice between wood and aluminum.
In Year 27, there was a small reduction in martin pairs to about 40. This seemed to be one of those normal decreases a colony goes through¡ªmaybe related to weather or other factors.
In Year 28, the pairs decreased to 31, and then, I became slightly concerned. I did note that the resident Great Horned Owl in the back woods could no longer be heard, and some kind of small hawk was making visits to the colony.
In Year 29, the pair count fell to 22 and I was now very concerned. I started to watch more carefully and more often. Finally, I determined that the small hawk was in fact a Cooper¡¯s Hawk. The hawk was having a field day with my colony and I was fit to be tied. I purchased a full-sized mannequin (standing upright) and I dressed it in shoes, clothes and a baseball cap. I moved the mannequin every 2-3 days around the site to keep it looking real, even changing position of the arms and hands. This did not work at al; the Cooper¡¯s kept coming 3-4 times a day. The mannequin did accomplish one thing though. No more sparrows or starlings. I also tried playing talk radio on the speaker system that I previously used for playing Dawnsong. This also did not work and this hawk even made a run through the housing while I was standing beneath them. You can bet some four letter words were used!
In Year 30 (2000), the first pair of scouts arrived on April 5. The colony continued to grow to an estimated air count of 25 pair by June 1. During this period, two hawks were now harassing the colony on a daily basis. The more I watched, the more I learned. The Cooper¡¯s Hawks were sneaking thought the big woods at the back of the colony. They were moving through the tree canopy, one, two, three, trees at a time until reaching the edge of the woods at the colony site. There they would sit until the timing was right to make a run at the PM houses. I observed that many times the hawk would get caught sneaking through the woods by an observant higher-flying martin. The martin would make an alarm call and all available martins would converge over the spot where the hawk was last seen in the trees. Whenever the hawk would move in the woods, the martins would move with him with harassing martin calls. Most times, the martins would drive the hawk out of the woods to a different area. On some occasions, the hawk would make it to the edge of the woods and make a run at the martin houses.
Sorry Hawk, Nobody¡¯s home!
Other times the hawk(s) would be successful in making it to the edge of the woods unseen. There, they would wait until enough martins were sitting around on perches or porches. Then, the hawk would make his 85 foot run toward the PM houses. The alarm call would immediately be sounded and all martins would be airborne, except for a few that would choose to turn around on the porch and head for the nest cavity holes. This was just the extra time needed for the hawk to slam into the house feet first and grab the martin trying to enter the hole. I actually have seen this happen four times in the last two years. I suspect that the hawk is sometimes lucky enough to grab martins while they are getting airborne and trying to gain full flight speed that takes 3-5 seconds. I¡¯ve never observed this type of capture, but I¡¯m sure it happens.
You can just imagine the harassment taking place every day, not to mention the martins being caught. The martins are in the air above the site 3-4 hours a day, alarm calling and squawking all the time. You can just tell when the colony is disturbed.
The 24 estimated pair, at the end of May, turned into only 12 active nests a short time later. Frustrated by what was taking place, the rest of the martins just left their nests, eggs and this site.
What was I as a landlord to do? Buy some owl guards and make each house look like a prison! No way was I ever going to do this! I would quit the interest first!
At a point where 12 nests had babies at various stages, a friend came to visit and look at the martins. It was Sunday morning and we already had one house down for inspection and back up again. We had moved only 15 feet, and were lowering another house, when the hawk slammed into the first house. The hawk did not get a martin, but just how brazen was he going to get? If I¡¯d had a gun, I would have taken a shot. Believe me!
That afternoon as I was walking past a bay window and saw a Cooper¡¯s leaving the site with a black male dangling from his long legs. He lighted into a dead tree on the side of my home and I ran outside to give chase, but the hawk flew off with the male. The martin was silent. All the other martins were in the air screaming! This is a sight I never want to see again, and once more I decided to let Mother Nature take its course. The colony was now down to 11-¨ö pair.
That Monday morning, I was up early and arrived at Home Depot fifteen minutes before they opened the doors. I just couldn¡¯t wait to get inside to purchase a 50' roll of 2" x 4" fencing 3' wide.
Wow! What a change of heart a bad night¡¯s rest will provide.
When I got home the PMs were already busy feeding their babies in 12 nests, and this included the now single female. With my electric winch, I ratcheted the first 3-Plex down (3 houses on one pole) and started taking measurements to fabricate the hawk guard to be installed. Males and females sat patiently on the top of the pole perches waiting to feed their young. It took an hour to make the first guard and I brought down the houses down for final fit and installation. The interruptions to the PMs was not more than 15 minutes at a time, and they really didn¡¯t seem to mind. The first guard was cut and bent wrong and was thrown away. So much for being in a hurry.
The guard fabrication went on for five days. A total of nineteen guards (five different styles) were installed by the end of the week. The guards were installed 2"-3" from the existing porches and porch rails. After the first guard was installed, I sat on the patio for the next hour. A male martin made the first martin approach and he landed on the thin guard wire in front of his nest cavity. As soon as he grabbed the wire his wings were fluttering with his body swaying back and forth to maintain balance. I knew then that I would have to add something to the landing wire.
The female made four approaches to the guard wire before landing, fluttering for balance and then jumping through to the porch which has a 3/8" guard rail attached. During the next forty minutes, they quickly learned how to just touch down on the guard wire and jump through to the porch rail. I was elated and knew I was on target.
The male was the best because he started flying right through the wire (wings folded) and landing on the porch guardrail.
My God! My martins are smart!
Back in my workshop I found a roll of ¨ù" O.D. white rubber tubing. I cut off a 2" piece and slit it open the long way. I installed it around the thin wire on the guard in front of the entrance hole. This would give them something more to grab when landing or exiting. Sure enough, it worked great. Now the birds, when resting, were sitting on the guard wire with its expanded diameter.
And so it went for one week. Houses down, measure, houses up, fabricate guard, houses down, install guard, houses up, sit and watch. All of this time 11-¨ö pairs of Purple Martins were feeding twelve nests of babies. Not once did an adult squawk at me or dive at me during the process. Do you think they really knew and appreciated what I was doing for them?
I eventually added 3/8" fiberglass rods (used in electric fencing) to the outside of the guards at heights consistent with each porch rail. The birds loved it and the job was complete.
When this installation was completed, I had approximately 1-¨ö weeks to go before all babies would be fledged. All babies were on the porches for feeding in their final days before first flights. I did not have one fledge early bird. All babies¡¯ first flights were from the fiberglass rod (rail) attached to the outside of the wire guard. Babies returning to the nest were a little clumsy at landing on the guardrail, but this is normal even without a guard in place. The hawks continued to make runs through the colony, but I did not observe even one hawk slam the house. I kept a daily count of adults and babies through this period and not one was lost. The single female raised her five babies by herself with very occasional help from the other mated males.
I fledged 55 babies from 12 nests (5 eggs did not hatch) and this is record rate for the colony.
Lessons learned: When you think there is a problem in your colony, watch it every spare moment you have for the signs that will tell you what it is. Confide in other knowledgeable Purple Martin people for what to look for and how to correct the problem. Take corrective action as soon as you know how, rather than wait two to three years and are forced to make changes.
John Schulz
