O — Total number of observations
A — Average amount of time per visit (minutes)
F — Number of feeding observations
The table shows that to some degree, size may have been a factor in the
average amount of time spent in the tree on each visit. Some of the
larger birds spent considerable time in the tree. My recollection,
notes, and photos I took indicate that for some species, e.g.
Rose-breasted Grosbeak (Pheuticus ludovicianus ), multiple feeding
(constantly consuming one fruit after another) occurred in each visit.
Other species, such as Tropical Kingbird (Tyrannus
melancholicus ), used the tree more for perching than eating. However,
even if larger birds may have monopolized “favorite” fruits, they did
not prevent smaller birds from feeding as there were always many fruits
to feed on.
However, the data do not suggest that smaller birds had more difficulty
obtaining the fruit from the seed capsules. Apparently, the seed
capsules, when ripe, are not sufficiently hard to be a factor in the
amount of feeding by smaller birds on Gumbo Limbo fruits. It has also
been previously noted that the fruit valves separate easily when ripe
(Scott 1984).
[ In (2022) I observed two different ways by which birds
removed the fruit from the seed capsule. A Gray-capped Flycatcher
(Myiozetetes granadensis ) simply pulled the fruit out of
its casing and swallowed the fruit. In contrast, a Social Flycatcher
(Myiozetetes similis ) seemed to take more time: it grabbed the
fruit in its beak and knocked it against a branch to remove half of the
casing. It then proceeded to knock it against a branch again to remove
the other half of its casing, before swallowing the fruit whole. The
different techniques used in removing the fruit valve may have been
related to the ripeness of the fruit (Pers. obs. 2/18/22)].
[My 2022 study showed the importance of Gumbo Limbo as a food resource
during the dry season. Eight species (Masked Tityra (Tityra
semifasciata ), Ochre-bellied Flycatcher, Brown-crested Flycatcher,
Boat-billed Flycatcher, Great Kiskadee, Social Flycatcher, Gray-capped
Flycatcher, and Tropical Kingbird) fed a total of 127 times in 2022, as
opposed to 18 feedings in 2021].
4.2 Competition for resources in Gumbo Limbo
Another way in which size is a factor is that larger birds often chase
off smaller birds, especially if there is limited fruit available. As
there were generally large numbers of fruiting capsules with edible
fruit on Gumbo Limbo, this was less of a factor than I observed withinHuevos de Caballo . Nevertheless, I observed two instances of
interspecific antagonistic behavior in the Llano Grande Gumbo Limbo, and
two instances in the cemetery Gumbo Limbo. In all but one case the
larger bird was the aggressor, with the exception being between birds of
the same size. Since Piratic Flycatcher (Legatus leucophaius ) is
by its nature pugnacious (it harasses other birds until they give up
their nests), it is not surprising that it was antagonistic toward a
bird of similar size. [As I recollect, these antagonistic behaviors
did not always dislodge the target from the tree, but only caused it to
move to another branch]. These results are summarized in Table 2.
Table 2. Antagonistic Behaviors in Gumbo Limbo