Housing placement advice please

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ron20m
Posts: 446
Joined: Sat Jul 03, 2004 3:01 pm
Location: Oklahoma/Norman

I currently have three Gemini racks and usually have 70 something pairs. The last three years Hawk predation has become horrible. i've been on this property 25 years and the trees are slowly encroaching on my housing.
This winter I want to re do the three racks to maximize protection.
I read the 40' from trees 30 ' from buildings.
Does anyone have suggestions on how to configure the houses?
Currently they are in a triangle, about 20 feet apart.
Do you think moving them closer would help, and how close could they be?
Any suggestions appreciated
ron20m
Posts: 446
Joined: Sat Jul 03, 2004 3:01 pm
Location: Oklahoma/Norman

I measured and the poles are exactly 20 feet apart which makes gourd to gourd about 16 feet.
I've wondered if moving them closer together might give the inside nests some protection.

Also measured and one tree was only 20 feet from the gourds on it's side, so I hope I can help a lot
Steve Kroenke
Posts: 4342
Joined: Fri Nov 28, 2003 6:49 pm
Location: Louisiana/Logansport

Ron,

If you can you need to move the gourd racks to the most open place in your yard. The farther away from trees better. I realize some yards are not large enough to move away from trees. And if your yard is becoming more tree encroached as you mentioned, then this is probably not possible. You mentioned that one tree was only 20 feet from the gourd racks. That is very close and would allow any Accipiter hawk a hiding place to ambush the martins. Can you remove any of these trees?

Moving the gourd racks closer together probably isn't going to help deter or minimize Accipiter hawk (Cooper’s and sharp-shinned hawks) predation. The martins will just be more concentrated around the housing rather than spread out some. The hawks can still swoop in and grab fleeing martins. I have had my gourd racks/houses spread out and closer together at my various martin colonies and it made no difference relative to minimizing Accipiter hawk attacks.

My current martin colony is open but the Accipiters still attack making low level surprise ambushes in the early mornings and evenings. Other Accipiters come high over and dive down on the colony and try to catch any martin that bolts out from gourds/houses. An open location is much better than a tree encroached site but these hawks can still catch martins at such colonies. I have seen a Cooper’s or sharp-shinned hawk launch from a tree over a hundred yards away from our colonies, come in like a bullet and try to catch any martin that is still flying around the housing. Again an open location is much superior to a tree encroached site, but these hawks can still attack in open areas and catch a martin.

I have a bluebird box near my martin colony and the bluebirds are excellent sentinels! They will give their high pitch whistle "bird eating hawk" alarm the moment they see an Accipiter nearby or actually coming in to attack. The martins go berserk, bolt and head for the sky! If you don't have any bluebird boxes in your yard, then this approach might help and give the martins more warnings of an impending hawk attack. I have been outside when my bluebirds gave their warning whistle and I was able to intercept an Accipiter coming in low and frighten the hawk away. The bluebirds warned not all the martins but me, too.

I also maintain a close watch on my martin colony during the evening at roosting time and in the early morning when the martins are first coming out. I’m on hawk patrol. Accipiter hawks are masters at hunting in dim light conditions. Sometimes just your presence around the colony can keep a hawk from attacking during the evening or early morning. And if one does enter the colony, you may be able to frighten him/her away.

For the last few years, what I have done is deploy a "forest" of martin and mourning dove decoys around the perimeters of my martin colony and my neighbor Bob's site. The plastic decoys can deflect an attacking Cooper's or sharp-shinned hawk and allow the real martins more time to escape. I place my decoys on poles between 10 and 50 yards out from the colonies. I have watched Cooper's hawks dive down like a peregrine falcon and hit the decoys rather than the fleeing martins. I have posted photos of these decoys on the Forum and you can search for them.

The decoy approach can help but may not deter all Accipiter hawk predation. We mainly have migrant Accipiters and merlins (small falcons) attacking our martins from February through April. The resident Cooper's hawks focus almost entirely on the martin fledglings during June and July and catch these youngsters AWAY from our colonies, usually several hundred yards. The decoys have almost no impact on the hawks unless the hawks try to catch a martin fledgling in our yards which rarely occurs.

The martin decoys seem to work the best and Cooper’s and sharp-shinned hawks and merlins will attack them. So far I have only seen the larger Cooper’s hawks attack the mourning dove decoys though a female sharp-shinned hawk or merlin is large enough to take a dove.

Some folks place the decoys directly on the gourd racks/houses and this can work too. I prefer to have the hawks "attack at distance" if possible to the give martins even more time to escape. I will be trying something a little different this season and will attach martin decoys on poles then attach the pole to some gourd racks so that the martin decoy will be higher up on the rack. An attacking Accipiter may go for the “slow” higher flying decoy!

You can move your decoys around periodically which may help "confused" a resident hawk that attacks at any time or a wintering Accipiter. But once a hawk has attack decoys over and over again, he/she may learn to avoid them and go for the real thing.

Some folks enclose their gourd racks/houses in a wire cage for owl and hawk protection. That approach would not help our colonies as nearly all attacks are on airborne martins, not martins perched on the housing. But if you are seeing the hawks fly up to the Gemini gourd racks and grab martins off the rings or gourd porches, then a cage may provide some protection. The cages will not stop the hawks from attacking martins that are flying to and from their nests. A cage could even slow down martins that bolted from inside if they have to navigate through any wire openings to get out.

You can try to setup a bird feeding station away from your martin colony and hope the hawks will focus of these birds instead of the martins. I tried that many years ago in Florida back in 2004 and it failed. The resident Cooper’s hawks continued to attack my martin colony and killed numerous adult parent martins during May and June. Many babies starved. My neighbor feeds wild birds in his backyard but the migrant Accipiters often ignore the “seed eaters” and attack our martins every season.

Cooper's hawks are thriving and nesting in all states except Hawaii and Alaska. Some cities have a flourishing population of Cooper's hawks and these hawks are now the most abundant raptor nesting in some urban/suburban locations. The Cooper's hawk is now a "city slicker"! It is no longer a "rare forest hawk"! Oh, the bird books need to be edited! The hobby of feeding wild birds has apparently helped these hawks to thrive and nest successfully in many cities. I believe this issue of Cooper's hawk predation on martin colonies will continue to grow and become more noticeable. All my martin colonies since the early 1980s in north Florida and now in northwest Louisiana have been attacked by Accipiters. All our current satellite martin colonies in northwest Louisiana are attacked every season.

I wish you the best and hope you can somehow minimize Accipiter hawk predation on your martin colony.

Steve
PMCA Member
300+ pairs of martins each season
ron20m
Posts: 446
Joined: Sat Jul 03, 2004 3:01 pm
Location: Oklahoma/Norman

Thanks Steve,
I have also done the perimeter decoy. Have some Martin and Dove decoys I set on wood fence. No way to say how many it helps but had the same philosophy. I wonder if the decoys might catch the eye of high flyers and actually bring them in was one of my thoughts.
Yes mine are Coopers also.
I can get 50 feet away from trees and 40 from a garage. I figured if they come over the garage they have another 30 feet to traverse of roof space to traverse. The closer I move them to each other the further from the trees they will be.
Coincidentally I have an occupied bluebird house about twenty feet away in a corner but have never noticed their alarm. They tend to sit on the nearby stockade fence so I'm sure they are watching.
I was also wondering if the owl guards over front porch might help an occasional porch sitter.

Thanks for the interest.
Ron
Steve Kroenke
Posts: 4342
Joined: Fri Nov 28, 2003 6:49 pm
Location: Louisiana/Logansport

Ron,

It looks like you have tried to minimize Cooper's hawk predation on your martin colony. I believe your biggest issue is how close the gourd racks are to trees. Fifty feet is still very close to trees. These hawks have explosive acceleration speed and will be on your martins in a fraction of a second. The martins need an open flyway to first drop down from the gourd racks, build up speed and try to distance a hawk. Any trees or buildings blocking the martins makes it easier for the hawk to catch them.

You could try some kind of curved rods (owl guards) over the fronts of the gourds that might help deflect a hawk from snatching a martin off a gourd porch. But I still think the hawk could flush the martin off the porch and catch the martin in flight. Cooper's hawks are not only fast but very maneuverable, too.

Have you noticed that the hawks are frightened of you and don't make attacks with you in the yard? If so, you could try several realistic scarecrows and move them around. I had some success with approach at one of my Florida colonies that was hit by resident Cooper's hawks. But it didn't last and the hawks got used to my scarecrows.

Are these hawks attacking when the martins have babies? If so, then you have resident Cooper's hawks which are more difficult to deal with since they are there all the time. Migrant or wintering hawks will leave to head to their breeding territories farther north.

I don't know if you would consider downsizing your martin colony. Perhaps having a smaller number of pairs may not be as noticeable to the hawks and reduce the attacks.

One of the worst enemies of a Cooper's hawk is the great horned owl. This owl will eat adult hawks and their babies. Perhaps you could try placing several decoy great horned owls in the trees or nearby on poles. The decoy owl may frighten away any hawk that is trying hide in the trees. Your martins may or may not respond to the decoy owl. If the owl is more obscured by trees, then the martins may not notice it. Kind of a wild idea but just something to think about!

I know it is most discouraging to have frequent hawk attacks on your martin colony. These hawks can seriously disturb the tranquility of the martins and make them highly nervous and terrified to socialize around their housing. I have been there several times with my Florida colonies, all of which had "tree problems" like you are having.

I wish you the best and please keep us posted on how things go in 2020 with your martin colony.

Steve
PMCA Member
300+ pairs of martins each season
ron20m
Posts: 446
Joined: Sat Jul 03, 2004 3:01 pm
Location: Oklahoma/Norman

Thanks Steve,
just saw this. NO! once I had a rack down at eye level and had put a decoy on one side and walked to the other side to put a second decoy on and a hawk hit the first one while I was standing right there!
Never noticed owl predation but have seen one all fall and winter sitting in my trees. Might not need a decoy.
Have 1/3 troyer horizontals and 2/3 Bo 11 on Gemini racks, will see if one style owl guard fits both
flyin-lowe
Posts: 2928
Joined: Wed Mar 29, 2006 8:49 am
Location: Indiana/Henry Co.

Since you have an established colony I would not be at all concerned about how close they are to your home. They do like to be around human activity but it is not like they are going to abandon a site simply because they are now 100 feet from your home instead of 40 feet. In fact, the hawks could be also using your home as a way to ambush and hide the fact that they are coming in. Once the hawks find your colony they will not leave it alone, at this point you just need to give your birds the best chance at escaping. I would also try attracting some other birds, either by feeders or other housing. The more eyes in the area the better. I have killdeer that nest on my property and they seem to be the best alarm system I have. They can spot a hawk from a long way away and when they sound the alarm the martins take notice.
2020 Currently 42 nest, 110 babies, 64 eggs left to hatch(6-22-20) HOSP count-8
2019- 31 Pair over 100 fledged
2018- 15 pair last count 49 fledged
2017 3 SY pair nested, 12 eggs total, fledged 10. 4 additional SY's stayed all summer but never paired/nested.
2016 1 pair fledged 4
2015 Visitors
2014 Visitors
2013 Moved 6 miles away, 1 pair fledged 2.
2012 30 pair fledged 100.
2011 12 pair (11 that nested), 43 fledged.
2010 5 pair, 21 eggs, 16 hatched, 14 fledged.
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