Resumen

SEIJAS, Andrés E. Injuries and parasites in Orinoco crocodiles (Crocodylus intermedius) in a river with high impact by anthropic activitiesFeridas e parásitos em crocodilos do Orinoco (Crocodylus intermedius) em um rio altamente impactado por actividades humanas. INCI [online]. 2007, vol.32, n.1, pp.56-60. ISSN 0378-1844.

During the last 50 years the Cojedes River System in Venezuela has suffered an important impact from human activities. In juvenile Orinoco crocodiles (n=101) from the most affected river northern sections a lower incidence of injuries (5.9%) was found, as compared to individuals of similar sizes (n=98) from less altered river sections in the south that showed 77.6% of injured individuals (c²=105.2, P<0.001). The most frequently found injuries were missing portions of the tail (70.5%) and partial or total mutilation of extremities (21.9%). Relatively large crocodiles (>600mm snout-vent length) showed a lower incidence of severe injuries (10.7%) than smaller individuals (24.3%), but the differences were not statistically significant (c²= 2.27, P=0.13). The rounded shape of many of the injuries suggests that they were caused by predatory fishes, particularly piranhas. A preliminary fish sampling demonstrated that piranhas are less diverse and less abundant in northern sections of the river, more affected by human intervention. Prevalence of some parasites (leeches, Paratrichosoma nematodes, and ticks) was also higher in southern river sections (c²= 12.5, P<0.001). The occurrence of leeches was relatively low compared to other crocodile populations around the world.

Palabras clave : Actividades Antrópicas ; Cocodrilo del Orinoco ; Parásitos ; Pirañas.