Bubbles from the Naturalist Jerry's tank - by Jerry Ligon

October 2007: Yellow-billed Cuckoo

On Bonaire, Netherlands Antilles, mid October is height of neo-tropical migration. This week Y-billed Cuckoos arrived in good numbers. I saw 15 on a bike trip through Wash./Slagbaai National Park along a 24 km road. Next day, on another bike trip I found 5 dead cuckoo along 13 km highway and 5 others flying across road. They arrive here in very poor physical condition. Pre-migratory weights as much as 70 grams in Michigan compared with cuckoo weight of as little as 29 grams in Curacao. This may be the largest weight loss documented for a migrating species.
Jerry

The preceding was a post that I submitted to BirdChat in October of 2005 about the hazards that migrants go through when leaving their breeding grounds and spent the winter in warmer climates, usually undergoing a journey of thousands of miles. In particular, I am keenly aware of Yellow-billed Cuckoo when they arrive on Bonaire, an island 60 miles off the coast of Venezuela. The following photos were taken on 23 October, 2007, when I spotted a Yellow-billed Cuckoo land within 10 feet of the ocean. It literally dropped out of the air. It was obviously fatigued and was breathing very rapidly and its wings were hanging limp and it was not particularly disturbed by my standing within 10 feet from it on the ground. After 15 minutes it seemed to recover then flew to a nearby shrub, still holding its wings loose from its fatigue. It then become very alert as I took several photographs and then realized what it had spotted as it dropped 2 feet and grabbed a lizard and swallowed it. It was one of our arboreal endemic anoles, Anolis bonairensis. It is apparent that it is critical for the survival of migrants to find food within a very short time after landing on dry land from such a long, non-stop flight across the Caribbean. This one was quite lucky and no more than 16 minutes elapsed before this newly arrived migrant found what it took to survive and then flew off to a more protected shrub.