Blood parameters of seabirds as indicators of body condition and subtle changes in the marine ecosystem

LUCIANA GALLO; FLAVIO QUINTANA; MARCELA UHART

Bogotá

Conferencia; II Conferencia Bienal de la Sección Latinoamericana de Wildlife Disease Association; 2015

Sección Latinoamericana de WDA, Asociación de Veterinarios de Vida Silvestre, Universidad de La Salle

Blood parameters (biochemistries and hematology) are useful in assessing health and fitness of individuals and populations of wildlife species. Furthermore, the health of upper trophic level animals is generally a reflection of the quality of their environment. To assess their applicability as indicators of body condition and environmental variations, we established baseline hematologic parameters and serum chemistries in a top predator of the Patagonian Shelf ecosystem, the Imperial Cormorant (Phalacrocorax atriceps, IC). Samples were collected at Punta León in Chubut, Argentina, from breeding adult males (n=184, 2004-05-10-11 seasons) and chicks between 16-35 (mean 25±3) days of age (n=110,2010-11). In addition, we explored inter-annual variability of these parameters at the population (all animals) and individual levels (only male adults recaptured in successive seasons). Our results suggest that blood parameters are moderate indicators of cormorant fitness, as defined by body mass and body mass corrected for body size (adults) or tarsus length (chicks). In adult males, only uric acid, urea, and glucose explained a small part of the variation observed, while in chicks triglycerides and total protein were the most representative factors. Inter-annual differences were detected in most blood parameters in adults and chicks at all levels examined. Furthermore, in chicks alkaline phosphatase and total protein levels differed with age and hatching order, respectively, whereas triglycerides and total protein tended to be lower in chicks that did not survive. While not definitive, these results, suggest that blood parameters reflect adult male adaptations to subtle environmental fluctuations and parental energetic requirements during the breeding season, and that chick?s values mirror parental variability. Future studies should be aimed at verifying the utility of blood parameters to predict chick survival. Similarly, linking blood parameters in breeding adults to reproductive success is a natural next step.