TOUCANS  Ramphastidae
Nothing says "Neotropics" like Toucans. Yes, the New World tropics have impressive macaws, but there are gaudy parrots elsewhere in the world; yes, there are glamorous hummingbirds, but hummers are also found in temperate North America forest; yes, there are other groups endemic to the Neotropics (antbirds, ovenbirds, tapaculos, gnateaters), but none are universally recognized by the man (or woman) on the street. Everyone knows and everyone loves toucans. And toucans exist only in the New World tropics.

No doubt this is because of their big and usually colorful bills. Keel-billed Toucan (left in a classic shot by Cagan Sekercioglu) is one of those species, and it ranges widely in the lowlands from south Mexico to northern South America. The huge bill is a very lightweight keratin, and is often used for plucking and swallowing fruit. Most toucans are primarily fruit eaters (Remsen et al. 1993), although though there are exceptions (detailed below).

It is easy to recognize a toucan one argument made for retaining them as a separate family in the face of biochemical data (see below; Short & Horne 2001, 2002) but there are significant differences in the size of the birds, the size of the bills, and the shape and length of the tails among the six genera. It is the big Ramphastos toucans, like Keel-billed, that mold the public image of this family. Short & Horne (2001) even use the word "Rainbow-billed Toucan" for this taxa. Yet there is much disagreement as to how many species there are. Recent books have listed as few as 34 (Short & Horne 2001, 2002), to 37 species (Dickinson 2003) to 41 (Sibley & Monroe 1990, Clements 1991). Short & Horne (2001, 2002) point to "massive hybridization" between "Cuvier's" R. t. cuvieri and White-throated Toucan R. tucanus, on one hand, and between "Yellow-ridged" R. c. culminatus, "Citron-throated" R. c. citreolaemus, and Channel-billed Toucan R. vitellinus, on another hand, supporting the more conservative approach to speciation in these birds, as proposed some time ago by Haffer (1974). This conservative approach as been adopted by the South American Checklist Committee. And all this before Navarro et al. (2001) proposed splitting Emerald Toucanet into 7 species (more below)! For the moment I adopt the 'middle-of-the-road' species-level taxonomy in Dickinson (2003).

Although Ramphastos toucans are impressive, I prefer some of the smaller araçaris and toucanets. One of my absolute favorites is Curl-crested Araçari (right in a stunning shot by Arthur Grosset). The rich burgundy and ivory contrasts are gorgeous, the long tail unexpected, and the little white "curls" on the crown a real topper. Rita and I lay on our backs in the middle of the Amazonian rainforest, lying on a tarp provided by Rio Cristalino Lodge, and staring up at the fruiting tree in the canopy some 100 feet above us. This is where our Curl-cresteds were feeding. Arthur Grosset took this photo on the grounds of Rio Cristalino Lodge (see below for links to the Lodge and to his web site).

Dickinson (2003) lists a dozen Pteroglossus araçaris, and I surprisingly discovered that (under that species list) I've seen them all. Among them are a wide array of green, yellow, black and red birds with various breastbands and differing bill patterns. They are not all easy to identify.

One of the ironies I find in some world birders is that they are able to say the word "araçari" just fine with its soft "c" sounds because of the little curlicue attached to the "c" [to wit, "arr-a-sar-ee"] when the same birders butcher the soft "c" (with the same curlicue) in jaçana, excitedly calling out "jah-KA-na." Oh well, who was it that said "consistency is the hobgoblin of small minds"?

The toucan on the Fruit Loops box, and at Disneyland, is patterned after the species with the memorable title of Toco Toucan (left). In the Brazilian Pantanal one can spot the Toco sitting in the canopy of a lone tree from some distance away. It is the only species of toucan adapted to non-forested habitats. It is also a toucan that indulges in much more than fruit. We watched it grab a baby from an oropendula nest and fly off to consume it. Remsen et al. (1993) found that the stomach contents of this species was quite variable, with 44% "fruit-only" and another 44% with mixed arthropods and fruit.

Recent molecular evidence has proven that New World barbets, toucans, and the two birds in Semnornis (e.g., the toucan-barbets) are more closely related to each other than they are to Old World barbets (Burton 1984, Prum 1988, Sibley and Ahlquist 1990, Lanyon & Hall 1994, Barker & Lanyon 2000, Johansson et al. 2001, Johansson & Ericson 2003, Moyle 2004). Given the evidence that toucans are actually 'big-billed New World barbets' when compared to barbets in the Old World, there are several different taxonomic approaches. One approach is to lump all of them into one huge Barbet family, leaving the Toucans as a subfamily (Dickinson 2003). The opposite approach is taken by the Handbook of the Birds of the World (Short & Horne 2002) sticks with the traditional approach of two families: all the barbets (including the toucan-barbets) in a barbet family and the toucans in a toucan family. They argue that it is easy to tell whether any bird in the group is a barbet or a toucan, and that the barbets are ecological counterparts on each of the three major tropical continents. This is true enough, but it is a bit like sticking your head in the ground to avoid the new evidence of relationships. There is now no serious doubt that toucans arose from the lineage of New World barbets well after that lineage had splintered into three directions. I prefer a more modern approach, now adopted by the South American Checklist Committee. They treat the two groups of Old Word barbets as two separate families, Asian Barbets [Megalaimidae] and African Barbets [Lybiidae], and then separate the three New World groups into separate families as well: New World Barbets [Capitonidae], Toucan-Barbets [Semnornithidae] and Toucans [Ramphastidae]. This treats all the groups on the same level. You can reach my pages on each of these families as follows:

Ridgely & Greenfield (2001) thought it might be an "oversimplification" to treat Emerald Toucanet (below; photo by Marc Fenner) as just one species. The subspecies lautus, albivitta, cyanolaemus, dimidiatus, and atrogularis, as well as Middle American wagleri and caeruleogularis, were formerly each considered separate species but Haffer (1974) treated them all as conspecific, and Short & Horne (2001) pointed out that the allopatric taxa are no more distinctive than those known to intergrade.
Navarro et al. (2001), reviewing the morphology of the various populations, suggest that Emerald Toucanet could be split into seven (7) species, but they cautiously (and appropriately) stated that "our studies ... led to more questions than they answered, and for that reason, the most appropriate conclusion to this contribution is to present topics that represent fruitful areas for further investigation." They recognized that their seven species were diagnosable under the Phylogenetic Species Concept but that species limits were much more difficult to determiner under the Biological Species Concept, as the populations are all allopatric. The calls were not diagnostic between populations, and their study did not include any molecular evidence.

It seems obvious to me that caution is warranted and that it will require additional studies, and (preferably) a molecular analysis to determine which (if any) of the populations are sufficiently evolved to be likely reproductively isolated under the Biological Species Concept. It was thus disappointing, but not surprising, to see that Clements' on-line "updates" accepted this seven-way split. Although this caused some glee among groups of tickers, the proposal has not gained wide acceptance. The South American Checklist Committee has not followed endorsed the split among South American populations. Clearly, there is much yet to learn about toucan taxonomy (among other topics) but, for now, it is enough to appreciate their variety and beauty.

Photos: Cagan Sekercioglu photographed the Keel-billed Toucan  Ramphastos sulfuratus in Rincon de la Vieja NP in northern Costa Rica in August 2000. Arthur Grosset photographed the Curl-crested Araçari  Pteroglossus beauharnaesii  at a fruiting tree at Rio Cristalino Lodge, Brazil, in 2003. The Toco Toucan  Ramphastos toco was in the Brazilian Pantanal in Aug 1999. Marc Fenner photographed the Emerald Toucanet  Aulacorhynchus prasinus at Monteverde in Costa Rica in April 1990. Photos © Cagan Sekercioglu, Arthur Grosset, Don Roberson, and Marc Fenner, as credited, used with permission, all rights reserved.

Many more outstanding Arthur Grosset photos are on his web page; he particularly features South America. Photos from around the globe highlight Cagan Sekercioglu's web site [Cagan is a grad student at Stanford]. Marc Fenner hosts a fine web site on birding Costa Rica.

Use this link to Rio Cristalino Lodge for information on this fabulous place.

Family Book

Short, L.L., and J.F.M. Horne. 2001. Toucans, Barbets, and Honeyguides. Oxford Univ. Press, Oxford.

I must confess that I don't actually own this book, nor have I done more that quickly glance through it in a bookstore. But every one of the Oxford Univ. Press series on bird families has been excellent, and this looks equally solid. I presume that the "meat" of this book has been summarized by the same authors in their Handbook of the Birds of the World series (Short & Horne 2002) which I do own and have studied.
     Consistent with Oxford books in this series, the introductory material is extensive and the species accounts thorough. Plates and illustrations more than adequately enhance the text. If I have any quibble, it is with the conservative approach to family level taxonomy but, then again, this was written before the molecular studies by Johansson et al. (2001) and Moyle (2004).
Literature cited:
American Ornithologists' Union. 1998. Check-List of North American Birds. 7th ed. A.O.U., Washington, D.C.

Barker, F.K., and S.M. Lanyon. 2000. The impact of parsimony weighting schemes on inferred relationships among toucans and Neotropical barbets (Aves: Piciformes). Molecular Phylogenetics and Evolution 15: 215-234.

Burton, P.J.K. 1984. Anatomy and evolution of the feeding apparatus in the avian orders Coraciiformes and Piciformes. Bull. Brit. Mus. (Natural History) 47: 331-441.

Clements, J.F. 1991. Birds of the World: a Checklist. 4th ed. Ibis Publ., Vista, CA.

Dickinson, E.C., ed. 2003. The Howard & Moore Complete Checklist of the Birds of the World. 3d ed. Princeton Univ. Press, Princeton, N.J.

Fry, C.H., S. Keith, and E. K. Urban, eds. 1988. The Birds of Africa. Vol. 3. Academic Press, London.

Haffer, J. 1974. Avian speciation in tropical South America. Publ. Nuttall Ornithol. Club, no. 14.

Hilty, S.L., and W.L. Brown. 1986. A Guide to the Birds of Colombia. Princeton Univ. Press, Princeton, N.J.

Johansson, U.S., and P. G.P. Ericson. 2003. Molecular support for a sister group relationship between Pici and Glabulae (Piciformes sensu Wetmore 1960). J. Avian Biology 34: 185-197.

Johansson, U.S., T.J. Parsons, M. Irestedt, and P.G.P. Ericson. 2001. Clades within "higher land birds," evaluated by nuclear DNA sequences. J. Zool. Syst. Evol. Research 39: 37-51

Lanyon, S.M., and J.G. Hall. 1994. Re-examination of barbet monophyly using mitochondrial-DNA sequence data. Auk 111: 389-397.

Moyle, R.G. 2004. Phylogenetics of barbets (Aves: Piciformes) based on nuclear and mitochondrial DNA sequence data. Molecular Phylogenetics & Evolution 30: 187-200.

Navarro, S., A.G. Navarro, A.G., A.T. Peterson, E. López-Medrano, and H. Benîtex-Diaz. 2001. Species limits in Mesoamerican Aulacorhynchus toucanets. Wilson Bull. 113: 363-372.

O'Neill, J. P., D. F. Lane, A. W. Kratter, A. P. Capparella, and C. F. Joo. 2000. A striking new species of barbet (Capitoninae: Capito) from the eastern Andes of Peru. Auk 117: 569-577.

Prum, R.O. 1988. Phylogenetic interrelationships of the barbets (Aves: Capitonidae) and toucans (Aves: Ramphastidae) based on morphology with comparisons to DNA-DNA hybridization. Zool. J. Linnaean Soc. 92: 313-343.

Remsen, J.V., Jr., M.A. Hyde, and A. Chapman. 1993. The diets of neotropical trogons, motmots, barbets and toucans. Condor 95: 178-192.

Ridgely, R.S., and P.J. Greenfield. 2001. The Birds of Ecuador. Vol. I. Status, distribution, and taxonomy. Cornell Univ. Press, Ithaca, N.Y.

Short, L.L., and J.F.M. Horne. 2002. Family Capitonidae (Barbets), pp. 140-219 in Del Hoyo, J. Elliott, A., & Sargatal, J. eds. Handbook of the Birds of the World. Lynx Edicions, Barcelona.

Sibley, C.G., and J.E. Ahlquist. 1990. Phylogeny and Classification of Birds of the World. Yale Univ. Press, New Haven, CT.

Sibley, C.G., and B.L. Monroe, Jr. 1990. Distribution and Taxonomy of Birds of the World. Yale Univ. Press, New Haven, CT.

Sick, H. 1993. Birds in Brazil: a Natural History. Princeton Univ. Press, Princeton, N.J.

South American Checklist Committee. 2004. On-line; Remsen, J.V., et al., eds. Subcomittee of the American Ornithologists' Union.



Page created 28 Sep-1 Oct 2004