4.3 Size analysis of birds visiting Huevos de Caballo
While the four dominant species — Hoffmann’s Woodpecker, Red-legged Honeycreeper, Rufous-naped Wren, and Yellow-green Vireo made constant visits back-and-forth to feed on the fruits, some of the larger birds stayed in Huevos de Caballo for much longer periods of time to continue feeding. I have already mentioned a Fiery-billed Aracari that I videoed taking at least eighteen fruits (one at a time) in succession. Similarly, Groove-billed Ani (Crotophaga sulcirostris ), White-winged Dove (Zenaida asiatica ), Keel-billed Toucan (Ramphastus sulfuratus ), Lesson’s Motmot (Momotus lessonii ), Pale-billed Woodpecker (Campephilus guatemalensis ), Great Kiskadee, and Clay-colored Thrush (Turdus grayi ) spent longer times in a tree. While larger birds also did this in Gumbo Limbos, given the relatively scarcity of fruit to be had in Huevos de Caballo trees (at most four different seed husks might be open at one time on a tree), these larger birds showed much more antagonism toward the smaller birds, and sometimes even toward birds of similar size. At times the competition for fruit even caused small birds to chase other small birds. However, even if these larger birds did not exhibit antagonistic behavior, by situating themselves on a branch either over or under an opened husk, they monopolized that fruit for as long as they were there.
In Table 3 I have divided the birds by size using the same criteria as I did above (i.e., larger or smaller than 15 cm) for the birds visiting Gumbo Limbo. I have also arranged them by actual size as is shown by their length in centimeters within the brackets (Garrigues and Dean 2014). Several things stand out when looking at Table 3 in terms of the size of the birds observed visiting Huevos de Caballo . The first and most obvious is that almost twice as many birds that visitedHuevos de Caballo were medium-sized (larger than 15 cm), and at least two (Keel-billed Toucan and Montezuma Oropendola) might well be considered “Large.” The second is that three of the medium-sized birds (White-winged Dove, Clay-colored Thrush, and Rufous-naped Wren) and two of the small birds (Yellow Warbler and Chestnut-capped Warbler) visited many more times than they fed. In contrast, three of the medium-sized birds (Keel-billed Toucan,
Table 3. Birds Visiting Huevos de Caballo