Luke Massey / Giant otter (Pteronura brasiliensis) feeding on a catfish (Loricariidae) with Cocoi heron (Ardea cocoi) scavenging remnants, Rio Cuiaba, Brazil

Luke Massey / Giant otter (Pteronura brasiliensis) feeding on a Pleco catfish (Loricariidae) Rio Cuiaba, Brazil

Luke Massey / Gant otter (Pteronura brasiliensis) feeding on Catfish (Loricariidae) in the Rio Cuiaba, Brazil

Luke Massey / Giant otter (Pteronura brasiliensis) feeds on a Catfish (Loricariidae). in the Rio Cuiaba, Brazil

Luke Massey / Cocoi heron (Ardea cocoi) with Catfish prey (Loricariidae) attacked by Black collared hawk (Busarellus nigricollis) Pantanal, Brazil..

Luke Massey / Cocoi heron (Ardea cocoi) with Catfish (Loraciidae) attacked by a Black collared hawk (Busarellus nigricollis) Pantanal, Brazil..

Luke Massey / Cocoi heron (Ardea cocoi) with Catfish (Loraciidae) Pantanal, Brazil..

Joel Sartore / Photo Ark / Leopard plecostomus (Pterygoplichthys gibbiceps) portrait, private collection. Captive, occurs in South America.

Joel Sartore / Photo Ark / Leopard plecostomus (Pterygoplichthys gibbiceps) head portrait, private collection. Captive, occurs in South America.