Evaluation of the Hematology and Biochemistry of Scarlet Macaws Before and After Reintroduction in Costa Rica
As part of a rehabilitation and reintroduction program of scarlet macaws (Ara macao), hematologic and biochemistry values were determined during captivity, at the release site, and once they were released back in to the wild. A group of 21 scarlet macaws (Ara macao), 13 females and 8 males were confiscated during 1993, 1994 and 1996. Their average age was estimated to be 20 yr. They were rehabilitated and reintroduced in 1998 and 1999 in the central Pacific area of Costa Rica. This species had disappeared from this area approximately 40 yr ago due to hunting and illegal capture for sale as pets. A soft release program was used to reintroduce the individuals. A special cage was developed to condition the animals to natural feeding behaviors. Two cages were constructed. One was hung inside the release cage while the other one was hung outside. The exterior cage functioned as a feeding trap device in order to feed the animals and recapture them for future analysis. Several artificial nests were built. Two were hung inside the release cage and eight were hung throughout the release area in order to encourage nesting in the area. An environmental education program was developed and executed. Farming communities and primary schools were visited several days each week to be educated about the reintroduction program as well as the multiple benefits that a program such as this would bring their communities. These benefits lead to the same ending-improving quality of life by introducing a commercial element because the project contributes to tourism, which will give them (the communities) another source of money for their own use. In addition, there is a spiritual aspect because future generations will see free-flying scarlet macaws (Ara macao).
Changes (before release vs. after release) in the hematology and blood chemistry values of released macaws were used to evaluate adaptation of the released animals. All of the birds had identical housing, diet and health status during captivity. The results of all analytes during captivity were within the range reported for this species. There were 19 individuals in the final release group. One individual died with of severe obstructive uropathy due to a renal parasite, while the second one developed bilateral ocular dysfunction related to the presence of cataracts. Two sets of blood samples (July, 1998 and September, 1998) were taken during captivity and two more (May 1999 and June, 1999) were taken once the animals were released. Data obtained both in captivity and after release were compared using nonparametric statistics to verify significant changes. All of the hematologic values, except lymphocyte, monocyte and eosinophil counts tended to increase over time. However, only seven of the 10 variables measured were statistically different before and after release. (Ht, Hgb, MCHC, heterophils, lymphocytes, monocytes and unopette cell count). Out of the nine biochemistry values (TP, glucose, uric acid, Ca2+, P, ALKP, CPK, ALT, AST) measured, six tended to increase (TP, Ca, P, CPK, uric acid, BUN, AST) and three to decrease (ALT, ALKP, glucose) but only five changes were statistically significant. (TP, Ca, P, CPK, ALT). According to the results, variables tended to increase 1 mo after the release date and then to decrease 1 mo after. Hematologic and biochemistry variables measured in this study, after the release, were not that different from the data published for captive individuals for the same species. Minor differences could be due to diet, environmental conditions, gender, laboratory procedures, or sample handling. It is reported therefore, that based on observations and the results after the release, the individuals were apparently healthy and that the changes found, were due to adaptation to several factors such as stress, hypoxia and exercise.