Toucans Skirmish Over Nesting Cavity
While walking early one morning last month at the Lookout Point (the “Mirador”) at Finca Cántaros, I heard an entirely unfamiliar, loud irregular banging–a drum-like clacking sound. I hurried to the wooded area nearby and found a pair of Yellow-throated Toucans diligently excavating a cavity at the juncture where a high branch had been cut years ago from an old Eucalyptus* tree, the “Rainbow Gum.” The Toucans’ huge beaks, which are astonishingly light, hollow structures, were striking the woody circumference of the hole as they used their beaks to excavate the rotten wood.
Suddenly, as I stood watching and photographing the hard-working pair, a flock of six Fiery-billed Aracari approached with noisy fanfare. These smaller, aggressive birds in the Ramphastidae or Toucan family, dive-bombed the Yellow-throated Toucans, which left the cavity area to counterattack. All then departed the immediate scene and went to squabble in nearby trees. There was croaking and screeching, the sound of rapidly beating wings, and short flights to and from the antagonists’ perches. After a few seconds of mid-air scare tactics on both sides, they all flew off in the same direction, taking their altercation elsewhere. It seemed like an unfair fight—six against two—but the Toucans seemed to give no ground, or air space.
Upon returning on subsequent days, I found alternating inhabitants in the cavity: first the Yellow-throated Toucans were back in charge, but then the next day, Aracaris were getting used to the ample space.
After a trip away from the reserve for over two weeks, I found neither species using the cavity. Yet both the Toucan and Aracari have been almost constant visitors around the reserve for the second and third weeks of March. Their courting behaviors are quite beguiling, and I observed that mates feed each other during this season.
Fiery-bill Aracari lay two eggs between January and April, and surprisingly, three or more adults may tend to a nest. These birds are residents of the southern Pacific slope up to 5000 ft (1500 m). My husband and I often refer to them as “motorcycle gangs” as they swoop into forest edges and garden areas in bands of up to 10 looking for fruit, as well as insects, eggs and nestling birds. On banana feeders, small birds like Tanagers must cede their places until the Aracari have taken their fill. They often hop around a few extra minutes as though to make it clear who’s boss.
An iconic tropical bird, the Yellow-throated Toucan eats mainly fruits, but also searches for insects, lizards and snakes, along with nestling birds. In late afternoons of this dry season period, Toucans often gather in small flocks in tall trees or dead snags to call out in loud chorus, sometimes answered by other nearby groups. They are quite common on both the Caribbean and southern Pacific slopes of Costa Rica where we are (1197 m), up to 3900 ft. I could find no definitive answer on how many eggs they lay (nests are high off the ground), but the months of nesting are January to June.
It remains to be seen if either of these stunning pairs will take possession of the now vacant Rainbow Gum cavity when the time for laying is right. If so, I will attempt to document the successful pair in their domestic nurturing roles. May they be left alone; life is tough out there for a Toucan!
* The Eucalyptus deglupta, native to the environs of New Guinea and Sulawesi, was planted in 1965 by the original owner of the property, Vito Sansonetti, the Italian founder of our town of San Vito. Two more magnificent specimens are also found on the property.
The Birds of Costa Rica – A Field Guide, by Richard Garrigues and Robert Dean. A Zona Tropical Publication from Comstock Publishing Associates, division of Cornell University Press, 2014.
A Guide to the Birds of Costa Rica by F. Gary Stiles and Alexander F. Skutch. Comstock Publishing Associates, division of Cornell University Press, 1989.