How to Safely Capture and Release a Banded Purple Martin:
Fishing For Martins
Reprinted from Update 4(4):28-29

James R. Hill, III
Purple Martin Conservation Association

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    Beginning in the summer of 1992, I expanded the PMCA's martin banding program to include all the nestlings reared at the colony site of Andrew M. Troyer, in Conneautville, PA, 15 miles SW of PMCA headquarters. Because of the cold, rainy weather in 1992, only 28 of his nestlings survived to fledging age. All of them were banded.  In May of 1993, while watching the daily arrival of subadult martins at his site, Andy noticed three (two SY females, and one SY male) with U.S. Fish & Wildlife Service aluminum leg bands. [It was necessary to use a pair of binoculars or spotting scope to see that the bands were present; consider looking over your martins' legs this spring with a pair of binoculars.] Andy was ecstatic; if they were three of the 28 nestlings banded at his site in 1992, it would mean that 10.7% had returned to their natal colony site to breed. This would be about double the published norm! If the literature is correct, about 75% of martin fledglings fail to survive their first year of life, about 20% disperse to breed elsewhere, and fewer than 5% return to breed at their natal colonies. Obviously, we had to capture those three subadults and read their band numbers to see if they were returnees.
   
    So, how do you go about capturing free-flying martins? As usual, necessity was the mother of invention. First, Andy and I waited until after these subadults had paired, built nests, laid eggs, and hatched some nestlings. If you capture parent martins in their compartments before they have accumulated at least that many weeks of parental investment, there is a chance they will abandon their efforts and the site. We discussed using the nighttime technique of Dr. Eugene Morton (see Update 4(1)), but ultimately decided to capture the banded martins during the daytime.

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    Because Andy watches his martins quite closely, we knew exactly which house and compartment each banded martin was nesting in, and now was feeding young at. To capture the first bird, we decided to try a fish net. First we lowered the winch-operated house about 6 feet. This brought the top of the house down from about 17 feet to 11 feet. Then we waited a few minutes for the parent martins to settle down and resume feeding at this lower height. In the meantime, Andy had fashioned an extension handle for his small-mesh fish net so he could reach the upper compartments from the ground. Next, we moved closer and waited for the banded bird to enter its compartment with food. As soon as it did, Andy ran up and blocked the entrance hole with the net. Surprisingly, the bird made no attempt to escape. We cranked the house down the rest of the way, opened the door (while covering the 7" x 7" opening with both hands), then carefully reached in and grabbed the bird.

    The very first thing you do when you've captured a banded bird is write down its band number, in case it squirms out of your hand before you're done processing it. Her band number was 8051-27076 and she had been banded in 1992, right there at Andy's colony site. She was nesting just 7 feet from the house she had hatched in. Next, as part of an ongoing diet study the PMCA is conducting, we collected the beakful of insects she still had in her grasp. We then weighed her (she weighed 54 grams) and photographed her (see Fig. 2). Finally, we gave her to Andy's 7-year-old son, Adam, to gently release. This was an unforgettable thrill for him.
    To capture the second banded subadult, we just repeated the entire operation at her nest site (Andy has four, active, 14-unit houses). Her band number was 8051-27088. Like the first female, she also weighed 54 grams and had been banded in 1992 as a nestling at Andy's site. Interestingly, she had hatched in a gourd attached to the house she was now using.

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    To capture the third and final banded bird, a subadult male, we decided we needed a better method — a method involving a shutter placed on the outside of the house, triggered manually, with a line, from the ground. After a little thought, Andy came up with his "Fishing for Martins" technique. He fashioned a lightweight, vinyl shutter that was attached above the entrance hole of the house with a loose screw, that also acted as the pivot point (see Fig. 3). To hold the shutter in the open position, Andy drilled a tiny hole in the face of the house and placed a cotter pin in it; the raised shutter rested on the cotter pin. Attached to the pin was the Monofilament line of his fishing pole. After setting up, we cranked the house back up, let slack out on the fishing pole, and backed off about 80 feet (see Fig. 1). We didn't have long to wait before the male came in with food and entered his compartment. A jerk on the pole pulled the cotter pin out of its socket, dropping the shutter. Cranking the house down, we removed the banded male, number 8051-27079. He, too, was banded the previous summer at Andy's place as a nestling. We were able to confirm that three of the 28 nestlings (10.7%) fledged from Andy's colony site in 1992, returned to breed at their natal colony site in 1993.

    The story doesn't end here. Later in the summer of 1993, another banded SY male showed up at Andy's and showed an interest in breeding, as did a banded ASY male! This last bird really excited us, because we knew it could not have been banded at Andy's colony (I had only begun banding nestlings there in 1992). So again, we went "fishing." The SY male was 8051-27094 and had been banded as a nestling in 1992, in an aluminum Trio Castle at PMCA headquarters, 15 miles away. The ASY male, also from our headquarters, was 8051-26927, and had been banded as a nestling in 1991, in a wooden house. If this meager sample size of 5 banded martins is indicative, it seems that martins do not necessarily imprint on the type of housing they were reared in. Two of the five were reared in a gourd or an aluminum house, but bred (or attempted to breed) in one of Andy's wooden, T-14 martin houses. Andy (not so modestly) claims that this was because of the superior quality of his new house design. Andy and I can't wait until 1994 to see how many banded martins return.

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    This same technique ("Fishing for Martins") can also be used for capturing troublesome House Sparrows and starlings, although, since they are less tame, the "fisherman" should be farther away, or hiding. A good hiding place from which to tug the line is inside a car, your house, or from a bird blind.
    A final word of caution. DO NOT ATTEMPT TO BAND YOUR OWN MARTINS! Banding birds requires both federal and state permits, lots of prior experience as an apprentice bander, and most importantly, special bands and pliers. People who illegally put their own makeshift bands on birds inevitably end up maiming and killing them. An ill-fitting band can cause a massive callous to form on the bird's leg, engulfing the band. This causes the bird to go lame, which ultimately leads to its death. To find a licensed bander in your area, contact your local Audubon chapter, or ask local game commission personnel.
     Since 1995, the PMCA has been using colored leg bands (in addition to the aluminum leg bands) with a 1-3 digit alpha-numberic combination that can be read with a high power spotting scope.  If you capture a banded martin, report the number to the Bird Banding Lab by calling 1-800-327-BAND.  You will receive a Certificate of Appreciation indicating where the bird was banded.  You can also report the band number via their website at www.pwrc.usgs.gov/bbl/

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