2.2 Study sites
Gumbo Limbo and Huevos de Caballo trees both grew in areas where
I did my daily bird walks. I therefore decided to incorporate the study
into my birding routine, spending time at each one of the trees I
encountered. Thus, the times and days when I observed each tree was
dependent on which route I took that day, how far that tree was from my
house, how long I took on other parts of the walk, and how far it was
from the terminus of the walk, which affected whether I revisited it on
my return. Given that variability, I tried in some way to normalize my
observations by limiting most of them to approximately one half-hour
(although at times I did less, and other times more).
During the study, the trees observed probably ranged in elevation no
more than 100 meters either above or below the town’s elevation (850
meters above sea level), and usually much less than that. All but one
site were adjacent to or very close to major roads. The study was
conducted over more than two months, with the first observations on 6
March 2021, and the last observations on 12 May 2021. [I have also
included some historical observations from previous years that I can
document with photos, but for which I cannot include the duration of
each observation].
Some of the trees were more isolated than others, and in somewhat
different environments. This not only influenced which species of birds
might be feeding on a specific tree, but also how easy it was to note
departure times, in particular, and sometimes even if a bird had fed. In
all but one of my sites, the trees studied were not next to or very
close to any other trees of the same species. The exception was in the
“woods above the cemetery” where a number of Huevos de Caballotrees had grown together. Unfortunately, some of these trees in that
location that had historically been used by different species had been
cut down prior to when I began my study, leaving many fewer trees to
attract birds at that site. Finally, as Gumbo Limbo fruits were no
longer available toward the end of my study, I concentrated more on some
of the Huevos de Caballo trees, and for the last part of the
study concentrated on one particular Huevos de Caballo tree that
was very close to my house.