John Shaw / Yacare caiman (Caiman yacare) Cuiaba River, Pantanal, Brazil, August.

Andy Rouse / RF- Yacare Caiman (Caiman yacare) cooling off, Pantanal, Brazil (This image may be licensed either as rights managed or royalty free.)

Jeff Foott / Yacare caiman (Caiman yacare) with butterfly on snout, Cuiaba River, Pantanal Matogrossense National Park, Pantanal, Brazil.

Bence Mate / Jacare / Yacare caiman (Caiman crocodilus yacare) two caymans, one with mouth open, Pantanal, Brazil.

Wim van den Heever / Julia heleconia (Dryas julia) butterfly on head of Yacare caiman (Caiman yacare) Pantanal, Brazil.

Nick Garbutt / Yacare Caiman (Caiman yacare) gaping to regulate its body temperature, with attendant hoverflies, the Paraguay River, Taiama Reserve, western Pantanal, Brazil, South America.

Luiz Claudio Marigo / Yacare caiman (Caiman yacare) restingout of water, in front of Pink Ipe trees (Tabebuia ipe / Handroanthus impetiginosus) in flower, Pantanal, Mato Grosso State, Western Brazil.

Angelo Gandolfi / Yacare Caiman (Caiman yacare) with mouth open to keep cool, Pantanal, Brazil.

Angelo Gandolfi / Yacare Caiman (Caiman yacare) at waters surface, Pantanal, Brazil

David Pattyn / Spectacled caiman (Caiman yacare) walking on a sandy shore at the edge of a river at night, Pantanal, Brazil

Luiz Claudio Marigo / Jaguar (Panthera onca palustris) dragging a Yacare Caiman (Caiman yacare) onto the bank of the Piquiri River. The Pantanal wetlands of Mato Grosso State, Brazil, October.

Luiz Claudio Marigo / Jaguar (Panthera onca palustris) struggling with a Yacare Caiman (Caiman yacare) in the Piquiri River. The Pantanal wetlands of Mato Grosso State, Brazil, October. Sequence 2/4

Luiz Claudio Marigo / Jaguar (Panthera onca palustris) in water with Yacare Caiman (Caiman yacare), its teeth around the back of the prey's neck. Piquiri River, The Pantanal wetlands of Mato Grosso State, Brazil, October....

Bence Mate / Jacare / Yacare caiman (Caiman crocodilus yacare) with young armadillo prey ib its jaws. Pantanal, Brazil. WINNER: Eric Hosking Award portfolio image 3/6 - Wildlife Photographer of the Year 2010

Pete Oxford / Jacare caiman bellowing {Caiman crocodilus yacare} subsonic boom causes water to vibrate. Pantanal, Brazil

Staffan Widstrand / Caiman {Caiman yacare} by river at sunset, Pantanal, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare) with fish school, Pantanal, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare) young in wetland, Pantanal, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare) two weeks old young in wetland, Pantanal, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare) waiting for fish to swim through open mouth in wetland, Pantanal, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare) standing on bottom of wetland, Pantanal, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare) swimming away, wetland, Pantanal, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare) waiting for fish to swim through open mouth in wetland, Pantanal, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare)fishing in wetland, Pantanal, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare) fishing in flooded plain, Pantanal, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare) in forest, Pantanal, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare) group in wetland at night, Pantanal, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare) baby seen from below, Brazil

Luciano Candisani / Jacare Caiman (Caiman yacare) with open mouth, Pantanal, Brazil

Bruce Thomson / Yacare caiman / Jacare (Caiman yacare), portrait, Pantanal, Pocone, Brazil.

Bruce Thomson / Yacare caiman / Jacare (Caiman yacare) on riverbank, Pocone, Brazil.

Bruce Thomson / Yacare caiman / Jacare (Caiman yacare) swimming in river, Pocone, Brazil.

Brandon Cole / Spectacled caiman (Caiman yacare), reflected back up onto surface of pond. Captive animal. Brazil, South America.

Brandon Cole / Spectacled caiman (Caiman yacare), split level view in the Pantanal wetlands region, Brazil, South America.

Brandon Cole / Spectacled caiman (Caiman yacare), juvenile resting at river surface at night. Amazon River, Brazil, South America.

Nick Garbutt / RF - Yacare Caiman (Caiman yacare) at the edge of the Piquiri River, northern Pantanal, Brazil. Gaping to regulate its body temperature (thermoregulation). (This image may be licensed either as rights...

Nick Garbutt / Yacare Caiman (Caiman yacare) at the edge of the Piquiri River, northern Pantanal, Brazil. Gaping to regulate its body temperature (thermoregulation).

Andy Rouse / Yacare caiman (Caiman yacare) mouth open cooling off, Pantanal, Brazil. Medium repro only

Andy Rouse / Yacare Caiman (Caiman yacare) cooling off, Pantanal, Brazil

Andy Rouse / RF- Yacare Caiman (Caiman yacare) submerged in water, Pantanal, Brazil (This image may be licensed either as rights managed or royalty free.)

Nick Garbutt / Gathering of sunbathing Yacare caiman (Caiman yacare) at the edge of a lagoon. Some gaping to regulate its body temperature +thermoregulation). Northern Pantanal, Mato Grosso, Brazil,

Franco Banfi / Yacare caiman (Caiman yacare), Paraguay river, Pantanal wetlands, Mato Grosso, Brazil

Franco Banfi / Yacare caiman (Caiman yacare), Paraguay river, Pantanal wetlands, Mato Grosso, Brazil

Franco Banfi / Yacare caiman (Caiman yacare) Paraguay river, Pantanal wetlands, Mato Grosso, Brazil

Franco Banfi / Yacare caiman (Caiman yacare),basking in the sun, Paraguay river, Pantanal wetlands, Mato Grosso, Brazil

Franco Banfi / Detail of the leg of a Yacare caiman (Caiman yacare), Paraguay river, Pantanal wetlands, Mato Grosso, Brazil

Franco Banfi / Yacare caiman (Caiman yacare), peering out of water, Paraguay river, Pantanal wetlands, Mato Grosso, Brazil

Franco Banfi / View finder of camera showing Yacare caiman (Caiman yacare), Paraguay river, Pantanal wetlands, Mato Grosso, Brazil