Environmental message: Whatever we do on land affects the ocean and all the plants and animals that live there. Help to keep our ocean healthy by joining a beach clean-up. Dusky dolphin Lagenorhynchus obscurus I am sometimes seen in groups of over 100 individuals. I hunt mainly during the day, and like to swim fast and energetically, sometimes doing somersaults and making splashes. I am dark grey on my back and white on my stomach. I grow to 2m in length and weigh up to 100kg. I communicate using whistles, clicks and squeaks. Humpback whale Megaptera novaeangliae I can grow up to 18m in length and 40 tonnes in weight. I have long white flippers. I can dislocate my lower jaw so that I can open my mouth wider to eat more!I can be seen around this coast between May and December. I can reach an age of 50 years or more.I have a unique song which can be heard by other whales many kilometres away. Bryde’s whale Balaenopetra edeni I eat fish such as sardine, anchovy and maasbanker. I can grow up to 15m in length and weigh up to 20 tonnes.I communicate using loud, low-frequency moans. Long-beak common dolphin Delphinus capensis I can be seen in groups of hundreds and even thousands of dolphins at a time. I am energetic and love riding the bow waves of boats and leaping out the water. I can dive up to 280m and hold my breath for up to 8 minutes.I eat fish and squid – which we catch by working together in schools. Heaviside’s dolphin Cephalorhynchus heavisidii I am a small dolphin and only live on the West coast of Southern Africa .I am very playful and enjoy surfing in the wake of boats, and jumping into the air and turning around before falling back into the water. I eat hake, goby, horse mackerel, octopus and squid. I grow to a length of 1.7m and a weight of 75kg.