Mammals
Creatures

MammalsMammalia

Class13 species

Marine mammals are air-breathing, warm-blooded vertebrates that give live birth and nurse their young. They possess streamlined, fusiform bodies, with forelimbs modified into pectoral flippers and horizontal tail flukes for propulsion. A thick blubber layer insulates most species. Cetaceans, comprising dolphins and whales, breathe through a single or double blowhole located on top of the head. Dugongs, the 🌊 Red Sea's only sirenian, breathe through nostrils positioned on the snout. Body lengths vary widely, from common dolphins at 1.7-2.4 m (5.6-7.9 ft) to large whale species exceeding 15 m (49 ft). Dugongs typically reach up to 3 m (9.8 ft) in length and weigh over 400 kg (880 lb). Most species display countershading, with darker dorsal surfaces and lighter ventral surfaces.

These animals inhabit open water, reef slopes, and along drop-offs, observed from the surface down to several hundred meters. Dugongs are found exclusively in shallow, sheltered bays with extensive seagrass beds, typically at depths of 1-10 m (3-33 ft). Cetaceans are primarily carnivorous, feeding on fish and squid, often foraging cooperatively in social pods. Dugongs are strictly herbivorous, grazing on seagrass, and typically occur singly or in small groups. Dolphin species are commonly encountered by divers, sometimes displaying curious behaviour, while larger whales are observed less frequently.

How to recognise mammals
TorpedoStreamlined and muscular, built for open-water speed - jacks, tunas, barracudas.
  • streamlined, torpedo-shaped body
  • horizontal tail flukes for propulsion
  • pair of pectoral flippers
  • regularly surfacing to breathe air
  • smooth, typically hairless skin

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Last Update: August 8, 2026