Resumen:
Dwarf caimans (Alligatoridae: Paleosuchus palpebrosus and Paleosuchus trigonatus), are small
crocodilians exhibiting cryptic behaviour and complex habitat use that occur throughout the
Amazon region. Our goals were to evaluate individual home range, habitat occupancy and
movement patterns where they occur in sympatry in relation to seasonal water-level variation.
We tracked five P. palpebrosus and seven P. trigonatus using VHS radio transmitters along the
shores of two streams directly influenced by the flooding pulse of the Purus River. Paleosuchus
palpebrosus individuals moved greater distances on a daily basis and had larger home ranges
than P. trigonatus, and the species had different responses to increases in water levels.
Paleosuchus palpebrosus moved into flooded forests, as do their principle prey species.
Conversely, larger P. trigonatus individuals usually remained near the main stream, and were
relatively sedentary. Intraspecific home-range overlap was higher than interspecific overlap in
both species. Thus, habitat occupancy patterns as a function of water-level variation might
facilitate coexistence of the two species of dwarf caimans in the same location. This study
shows that when living in sympatry under a seasonal flooding regime, Paleosuchus species
show a degree of habitat partitioning evidenced by different daily movement rates, home-
range sizes and home-range locations
