Monday 7 April 2014

Costa Rica

My tenth Ornitholidays tour to Costa Rica was especially enjoyable, with a small group and a new itinerary that involved less travelling than my previous ones. We saw 32 hummingbird species, such as this pair of Fiery-throated Hummingbirds up in the mountains. (Click to enlarge). Each one weighs 5.7 grams, a real heavyweight in comparison with the Stripe-throated Hermit (2.6 g). They can consume twice their weight each day - mostly nectar but also insects for extra protein. On the left is a male Violet-crowned Woodnymph. Among all animals, hummingbirds have the largest heart and brain proportionate to their weight. And although they always seem to be buzzing around in hyperactive flight, in fact they only fly 20% of the time.

Elsewhere we searched a stretch of river for the beautiful Sunbittern, and soon found this juvenile feasting on tadpoles. An adult would have similar plumage but a longer bill. Nearby we found one parent, and downstream a riverside nest where the other was incubating a single egg (though two is the normal clutch size). Though superficially heron-like, the Sunbittern is in a family of its own.

 Keeping on the waterbird theme, we came across a colony of Boat-billed Herons, normally strictly nocturnal but here content to sit in the sun, on its nest among the papyrus. Its diet of fish and crustaceans does not differ much from other herons, but it alone uses its bill as a scoop.

Tinamous always look to me out of proportion: like a small child's drawing of a bird. This is a Great Tinamou that wandered across the track behind us in Carara National Park. They are more often heard (an eerie whistle) than seen, and only the male has any part in incubating and raising young. 3 to 5 turquoise eggs are laid in a depression on the ground; and a few minutes after hatching the male leads the patterned, downy chicks off into the forest. 

Not far from the tinamou, we watched Blue-crowned and Red-capped Manakins bathing. But in a different part of the same forest, we watched this male Orange-collared Manakin at its lek. In the breeding season, manakins spend up to 90% of the time displaying, with greatest intensity when a drab green female appears. Their snapping sound (like breaking a dry twig) is not a vocalization, but made by the males' wings; they also have a variety of whistles and chirrups. Feeding on large fruits takes little enough of their time, such that they can carry on clubbing. Little surprise that males play no part in the nesting chores.

The Resplendent Quetzal was one bird we all hoped to see. We found this male in the mountains at about 2300m, perched in a favourite avocado tree - which also attracted another male and two females. They are especially ornate members of the trogon family, and nest in holes in dead trees. It is the national bird (and currency) of Guatemala, a nation that has fallen well behind Costa Rica in protecting its forests. Ironically, the national bird of Costa Rica is a humble clay-coloured thrush whose claim to fame is its song, which wakes everyone up much too early in the mornings! 

Many thanks to Herman (manakin) and Chris (tinamou and heron); the other photos are mine.