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Soon after
building Cecropia Camp, my thatch hut at Heliconia Haven, I found a nearly perfect
oropendula nest (images at sides) that had fallen from a huge ceiba tree. I hung it
under my roof. Within two months, I noticed a pair of small birds building a nest
within the original opening for the oropendula. Silhouetted above are my friends, the pair of
olive-backed euphonias that have now been nesting here for over four years. I have
been fortunate enough to have seen 4-5 of the fledgling flights, as newly emerged chicks reluctantly left their nest.
The most fascinating aspect of these birds is their elaborate charades to deter predators.
Both parents participate in nest building and in feeding the young and they
always seem to fly together. As they approach the nest with building material
or food, they stop 4 or 5 feet away
on a bush or house-pole. For many
seconds, they look fore and aft, searching everywhere for any potential
predators. Then, one at a time (usually the male first or solely), they begin
making short feigning flights of 2-3 feet, always returning to the same spot. Finally, when they feel safe,
they both simultaneously fly up to the nest entrance but, only one
goes in (usually the female first) while the other returns quickly to the original pole
or bush.
The "pole sitter" continues feigning flights and searching
for predators. Then, when the
"nest bird" is ready to switch, signals are exchanged, and
once again, they make a
simultaneous exchange, swapping places so quickly, that
a predator
would see little more
than a blur. How did they learn this behavior?
Amazing!
(see "My Recommended Books", A
Neotropical Companion, John Kricher -
an excellent resource for understanding symbiotic relationships in the
tropics)
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