Source: The Wormwood Mutiny, pg(s). 88
The dwarf caiman, or dwarf cayman, is a small crocodilian that look like its older family member the caiman, mostly found in coastal waters and rainforest waters. Pirates and other spellcasting sailors often use dwarf caiman as familiars.
Dwarf caiman have two abilities that help them hunt. The first is that they can hold their breath, staying perfectly still. Once they decide to strike, they explode at the prey, moving exceptionally fast.
Dwarf caiman will often hunt by camouflaging themselves to look like driftwood. As they live in the warm waters, they stay still for hours waiting for the perfect time to strike to catch their prey. The dwarf caiman prey on birds, fish, lizards, and small mammals.