Abstract
The U.S. portion of the "Puerto Rican Parrot Project" at the El
Yunque Rain Forest Station in Puerto Rico has recently been
placed under the directorship of Miss Kelly Brock. Kelly is doing
some very good things with the project. After Dr. Jose Vivalde
(Director of the project for the Puerto Rican Dept. of Natural
Resources) and I had discussed the situation with Kelly in depth,
she has been able to convince the U.S. government wildlife officials
to allow her to move the parrots from completely enclosed
housing quarters into outside cages which are half covered and half
exposed to the open air, rain and sunshine. There are also good
indications that, when a location is found, the birds will be moved
to a lower and drier location in the park. I personally believe that
the constant high humidity and cool temperatures of the present
location are primarily responsible for the decreased number of
eggs hatched in recent years. The physiology of the growing
embryo within the egg is interesting. The embryo must expel large
amounts of metabolic water, as vapor, through the eggshell during
its growth. If the outside humidity is too high, there is not a sufficient
differential water vapor concentration gradient between the
inside and outside of the shell for this exchange to take place and
the embryo dies.