- Calf
- Camouflage
- Canid
- Carnivoran
- Carnivore
- Carrying capacity
- Cartilage
- Cave
- CBD
- Cetacean
- Chameleon
- Cheetah
- Chondrichthyes
- Claws
- Climate
- Climate change
- Climb
- Coastal forest
- Colony
- Coloration
- Communication
- Competition
- Congo Basin
- Conservation
- Consumer
- Coral reef
- Countershading
- Courtship
- Crawl
- Creature
- Critically endangered
- Crocodiles
- Crops
- Crustacean
- Cub
- Cyclone
