Raptor Banding with Bill Clark

by Chuck Cornell

Since that day, I have become a helper to Bill and have learned a lot. In fact, I learn something every time I go and now feel fairly confident when making an ID of a hawk be it a juvenile or an adult. Bill is a patient teacher and allows you to learn at your own pace and within your comfort level. During the first few outings with him, my main tasks were to watch for hawks as he drove and straightening out the nooses on the traps after we caught a bird. 

Whenever I talk about banding raptors one of the first questions is “What kind of traps are used to catch the birds?” The traps that Bill mainly uses are call Bal-chatri or BC traps. They are based on the traps first used in India for falconry. India has had falconry for at least 600 years and somewhere in that time frame the Bal-chatri trap was developed in order to capture hawks. The original trap was a cage made from cane and on top were horsehair nooses. Mice or birds were placed inside the cage and when the hawk tried to get the critter their toes would become ensnared in the nooses.

Today’s traps work the same way, but they are usually made from hardware cloth and the nooses are monofilament. Bill usually packs three to five traps in the car and they are baited with a variety of lures to be attractive to the variety of raptors we have here in south Texas. Lures are the term used instead of bait because they are not killed (usually) during the capture. 

Lures used are mice, gerbils, house sparrows, collared doves, and pigeons. Usually there will be one or two traps with a sparrow/mouse combination. The sparrow keeps the mouse moving and movement is what attracts the birds. Doves or pigeons are solitary and have their own style of trap. Gerbils are generally in pairs although they can be in with a sparrow as well. Two mice together is another common combination.

The Bal-chatri traps are weighted with a dumbbell so that the bigger birds don’t fly away with them. Kestrels are too small and light to fly with the traps so they don’t need weights on them. 

The three most common styles of trap Bill uses are square shallow traps, a dome, and what he calls Quonset hut which are oblong traps with a curved top. In the United States only those who are permitted through a trapping permit, banding permit, or falconry permit may trap a raptor. 

Another trap I’ve seen used is a bow net. Bill has one that at this time is used exclusively for Kestrels. It has a small wire box that holds the lure and a net that when tripped will cover that bird and hold it until it’s retrieved. These work amazingly well and are quick. The trap operates with a set of springs; the bird trips the trap when it hits the wire cage. Healso has a bow net that is triggered manually with a tug of a rope. These require more of a setup as opposed to the easily used Bal-chatri traps which are simply tossed out the window of a moving car.

The way we most often do banding is road trapping. This is simply driving through an area and looking for raptors perched in trees or telephone poles along the roadside. Bill is exceptional at spotting birds and he is usually correct in his ID at a long distance. He will usually stop back a ways and check the bird with binoculars to confirm what it is. He will then call out what traps he wants to use. “Give me two mice and the sparrow/mouse” and I will reach into the back seat and grab the requested traps.

Depending in which side of the road the bird is on will determine where the traps go. The traps are placed opposite the bird so that they don’t see them being placed on the ground. Usually if it’s on my side I will open the door and toss them out. Tossing from a lower height gives a better chance that they will land upright, although that’s not always the case sincethe traps are tossed as the car is moving. We then drive a short distance and U-turn again to watch the hawk.

If it’s hungry and eager they will already be at the trap and caught by the time we turn around. This is of course the textbook situation, it doesn’t always go that way. We have sat as long as a half an hour waiting for the bird to come down. Sometimes they will come down, land, and just stare at the trap. Other times they will hover over it and maybe land or maybe just make a pass and go back up to the wire. Birds that have already been banded will no longer go after the trap. They have a long memory about the experience. On rare occasions we have caught banded birds but usually they were birds that were banded as chicks and as such were banded in the nest and have no memory of traps.

The majority of hawks we capture and band are Harris’s, American Kestrels, Gray, Red-tailed, and White-tailed. Other raptors caught include Merlin, Red-shouldered, Cooper’s, and Swainson’s Hawks, and White-tailed Kites. Some we have unsuccessfully attempted are Roadside Hawk, Zone-tailed Hawk, and Common Black Hawk.

After the bird is caught we drive quickly to the trap to retrieve it before it becomes too stressed or drags the trap into traffic. I usually grab the bird and the trap while Bill pulls the car to the shoulder and opens the back. He then collects the remaining traps while I release the hawk from the nooses. The bird is then put into a can until we can move to a quiet area to process the bird. 

Once captured, the bird is quickly untangled and placed in a receptacle for processing