Know your coffee birds: Emerald Toucanet

The Emerald Toucanet (Aulacorhynchus prasinus) is the most widely distributed member of the toucan family. It can be found from Mexico through Central America south to Bolivia. As might be expected for a species with such as broad geographic range, there are many subspecies — at least 17. They vary by throat color, facial pattern, and the color and pattern of the bill. Some researchers believe that some of these may actually be separate species, with perhaps four different species in Central America, and at least three in South America.

Emerald Toucanets are, as the name implies, smaller than toucans, at a little over a foot long. The sexes look alike, although males have slightly larger bills than females. Nobody is positive why this difference exists, as one study discovered it is not related to differences in diet or foraging (which is often the case when both sexes share territories year round). These toucanets nest in well-concealed tree hollows, and live in small flocks in the non-breeding season. They are found in open woodlands, including shade coffee plantations, from around 900 to over 3000 meters.

While they eat big insects and small lizards, fruit forms a large part of the diet of Emerald Toucanets. Therefore they are important dispersers of the seeds of tropical trees and shrubs. They have large feeding territories, so they encounter many species of trees, up to 47 at one Costa Rican study site alone. Although they are the smallest members of the toucan family, they’ll even consume large-seeded fruits, repeatedly regurgitating and reswallowing a fruit until the seed separates from the pulp and can be discarded. For the most part, seeds pass through the digestive system, though, and it’s been determined that those have a higher germination rate than seeds that merely drop to the ground in the fruit. All these factors make Emerald Toucanets an integral part of tropical forest ecosystems.

Because this species favors open forest habitats and forages in the mid-canopy, shade coffee farms are suitable habitat for them — and likely quite important in regions where other deforestation is high. Counter Culture Coffee chose the Emerald Toucanet for the new label of its Cafe San Ramon coffee because it is found at one of the main suppliers of these beans: Finca Esperanza Verde in the Matagalpa region of Nicaragua. In fact, when Counter Culture was redesigning the label and asked for a recommendation, I suggested this species (and the subspecies on the label is the correct one!). Just to keep myself honest, I’ll will be at Finca Esperanza Verde this week doing some bird surveys and bird banding, and hope to see a few Emerald Toucanets in the process.

Credits and references

Top photo of a “Blue-throated” Emerald Toucanet in Costa Rica by Laura Erickson; used with permission. Middle photo of the nominate form of Emerald Toucanet, in Honduras, by Brian Gratwicke, under a Creative Commons license.

Puebla-Olivares, F., E. Bonaccorso, A. E. de los Monteros, K. E. Omland, J. E. Llorente-Bousquets, A. T. Peterson, and A. G.
Navarro-Siguenza. 2008. Speciation in the Emerald Toucanet (Aulacorhynchus prasinus) complex. Auk 125:39-50.  For an excellent discussion of this paper and the taxonomy of Emerald Toucanets, see Nick Sly’s blog posts on the topic.

Riley, C. M. and K. G. Smith. 1992. Sexual dimorphism and foraging behavior of Emerald Toucanets Aulacorhynchus prasinus in Costa Rica. Ornis Scandinavica 23:459-466.

Wenny, D. May 2000. Seed dispersal, seed predation, and seedling recruitment of a newtropical montane tree. Ecological Monographs / Ecological Society of America, 70 (2): 331-351.

Wheelwright, N. T. 1991. How long do fruit-eating birds stay in the plants where they feed? Biotropica 23:29-40.

Wagner, H. O. 1944. Notes on the life history of the Emerald Toucanet. Wilson Bulletin 56:65-76.

Posted in Birds and other biodiversity,Know Your Coffee Birds series