Yellow-billed Cuckoo Survey and Telemetry (at Cibola)

Two days ago, I did a Yellow-billed Cuckoo survey at one of our Cibola National Wildlife Refuge sites called “Crane Roost.” I had vague/traumatic memories of this site from last year, running away from very small yet annoying mosquitoes. This survey was no different. As soon as you even think about entering the mesquite or cottonwood/willow stands, mosquitoes are buzzing in your ear and finding any inch of bare skin to bite. These little bloodsuckers were not nearly as large as the ones I just had to deal with in Idaho, but they were still a pain! Regardless, the survey went very well! As soon as I played my first call on my first stop, a nearby cuckoo started its “coo” call, and another started in the distance. It is thought that only females make the “coo” call (almost like a dove but more repetitive), but no one knows for sure. I encountered 3 other coo-ing cuckoos throughout the site, all of which were very responsive, which makes them good candidates for capture. On my last survey point, one flew right over to me, and started excessively coo-ing. It was unbanded, and probably un-paired, since it didn’t show any aggression or territoriality. I moved on and found 2 more of my coo-ing birds, and those were unbanded as well. All three birds seemed to have a defined territory, and often called back and forth to each other, probably letting the other know it was still there. While looking for the fourth bird I detected on my survey, my playback call was answered by a contact call (the classic “kuk-kuk-kuk-kuk-kowlp-kowlp-kowlp” cuckoo call). This area overlapped with the territory of a coo-ing bird, so there is potentially a pair in the area. At one point, there was a delayed voice exchange. But after walking all through the thick mesquite, the birds quieted down and never alarm called at me. Cuckoos are a hard nut to crack though, and it is really hard to say what is going on at a site from only one day of observation.

Three days ago, I radio-tracked a bird that has been jumping around one of our sites, named GRE. It was caught near a known nest that was being sat on by DG, another transmittered bird, so there was potential that it was DG’s mate. I sat near the nest in some camo, but of course DG figured out I was there and I had to reposition in the thick willows where he couldn’t see me as I radio-tracked. With my view of the nest obstructed, I wasn’t quite sure what was happening, but it sounded like GRE was very nearby DG’s nest after she had come off her roost about 200 meters away. The birds were doing vocal exchanges, and switching places near the nest quite a bit, so it looked like GRE was probably on the nest. DG is very smart though, and very territorial, so I had to be super sneaky and quiet under my camo; because he knew I was there, he didn’t go very far away.

Eventually when it seemed like DG left the nest area, GRE came back in. It really sounded like GRE was on the nest, so I walked in for a better look since DG seemed to be out of earshot. Sure enough, a bird with a transmitter was sitting on it, and GRE’s signal was coming right from the nest; DG was at least 150 meters away! Within minutes, DG arrived, as if he somehow knew an intruder was near his nest. He started knocking (a cuckoo alarm call), so I backed off and let them figure things out. DG took GRE’s place on the nest (as if to say “I’ll do it you nincompoop!”), and GRE went off foraging. It really looks like DG is the more territorial of the two birds, and spends much more time on the nest than GRE. There is one other nest with unknown ownership, so sitting by it may be the best option to find out if any of our other telemetry birds are sitting on it. Cuckoo telemetry is very tricky. You have to stay far enough away so that you aren’t disturbing the bird, but close enough to understand what is happening. The best thing to do is to find a small open area in good cover (like the short/dense willow!), and stay there as long as possible. As long as you aren’t moving, you can get a good sense of the places your cuckoo is visiting/re-visiting, or sitting for long periods of time. Of course, this is easier said than done, and just when you feel like you get into a great position, your cuckoo books it.  If a cuckoo re-visits its roost location a few hours after getting off roost, chances are it is returning to a nest. Or, if it doesn’t seem to be doing much at sunrise, it may be taking over a nest-sitting shift.

Yellow-billed Cuckoo Field Work...My first 2 days in Blythe, CA

Yesterday, Alex and I started our first day of work for Southern Sierra Research Station on a Yellow-billed Cuckoo project (check out a post about our road trip here). This is the same project we worked on last summer.  We are based out of Blythe, California, and have field sites on both the Arizona and California side of the Colorado river.  The sites are Cottonwood and Willow restoration sites managed by the Bureau of Reclamation for the benefit of Yellow-billed Cuckoos and other riparian species.  Mainly due to overpopulation and agricultural practices, the Colorado is a pretty sad looking river in this region, and important riparian areas that many bird species depend on have suffered.  Because there are not many other trees around, our sites are loaded with tons of bird species, including the endangered subspecies of the South Western Willow Flycatcher in migration.

On our first day of work, Alex and I joined Shannon and two other technicians for banding.  We help set up the net, but then Alex and I just roamed around in the distance, on call incase any birds needed to be flushed into the net.  We ended up catching 3 cuckoos!  I didn't stick around to take pics, because I was kind of antsy to start looking for cuckoos.  I ventured to the infamous "Black Annie" territory, a cuckoo we banded last year.  She'd been recaptured this year, but not given a radio-transmitter, as she had the year before.  She is clearly faithful to her territory, so any resight is very valuable information.  Unfortunately a Yellow-billed Cuckoo is just about the hardest bird to resight color bands on.  They sit low on branches and crouch over their feet, hiding their brightly colored bands..so, you have to be looking at the bird *as* it lands, or *as* it takes off, or as it scrambles around a tree trying ti hide from you.  Black Annie nested last year, but we couldn't capture her mate.  I was hoping to see the pair, but only got a brief glimpse of a cucko near her old nest.  It could have been her, her mate, or a fledgling from last year.  Nearby, a fledgling from last year was recaptured and given a radio-transmitter, showing natal site fidelity! (this bird is nicknamed "Fuzzy Jr." since his dad was named "Fuzzy."  Even though these sites are small, we are learning a ton of information about cuckoos because of them.  I was also able to check on a nest found a few days ago by Shannon that miraculously has 4 eggs in it (Yellow-billed Cuckoos typically have 3).  Here is a picture of the bird on the nest.  Despite having caught 2 birds near this nest, neither seem to be associated with it (one of them is "Fuzzy Jr." and the other was a cuckoo that migrated out of the site last night).

Yellow-billed Cuckoo on nest

Today Alex and I tracked Fuzzy Jr.  He stayed near his roost tree for awhile, but didn't seem to be responding to any contact calls in the area.  He sometimes called, but got no answers.  He is probably unmated, but we followed him anyways.  He showed himself a few times, foraging in the tall cottonwoods on the edge of the road, and he didn't move around very much.  At one point, he did a voice exchange with another cuckoo (potential mate?!), but he didn't move towards the bird.  Hopefully in the next few days we can start tracking birds on roost, which may lead to some nest finding!
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Three generations of yellow-billed cuckoos banded at CVCA

On July 7^th 2009, we captured a yellow-billed cuckoo at Cibola Valley Conservation Area near Blythe California. We named him Screech La Rue, put 3 color bands and 1 uniquely numbered gold band on his legs, then glued a radio transmitter to his back to keep track of him. Here's Lindsey about to release Screech with his new transmitter.

About a week later Screech started nesting, and 15 days after that we banded his 3 nestlings each with a yellow band on one leg and a gold band on the other leg. Here is Screech Junior, estimated to be 5 days old.

We never saw any of them again, and weren't sure if they had even made it, until July 31^st this year, when Screech Junior (the oldest of the 3) flew into our mist net. He still had his gold band, but his yellow band had fallen off. (Diane was very happy to see him again). We gave him 3 new color bands and attached a transmitter to him as well….

…and soon discovered that he was nesting, just 135 meters from his birth place! This shows that at least some cuckoos have high natal site fidelity. On August 14^th we banded his 3 nestlings, and they all successfully fledged by August 18^th. Here is his nest high in a cottonwood.

Hopefully next year they will all return to breed, and we will be waiting for them!