Nurse sharks (Ginglymostoma cirratum) are common bottom-dwelling sharks recognized for their docile demeanor. Their unique appearance and calm nature often capture public interest. Understanding their habitats provides insight into their ecological role and survival strategies. This article explores their global distribution and preferred living environments.
Global Range
Nurse sharks inhabit a wide geographical area, primarily found in tropical and subtropical waters across the Atlantic and Pacific Oceans. In the Western Atlantic, their range extends from Rhode Island in the United States, south through the Gulf of Mexico, and throughout the Caribbean Sea, reaching as far south as southern Brazil. The Eastern Atlantic population is found along the coast of West Africa, from Senegal to Gabon. In the Eastern Pacific Ocean, nurse sharks are observed from Baja California, Mexico, south along Central America to Peru, and also have a notable presence in the Indo-Pacific region. This extensive global distribution highlights their adaptability to various warm-water environments.
Preferred Habitats
Nurse sharks show a distinct preference for shallow, warm coastal waters, typically inhabiting depths under 20 meters, though observed up to 70 meters. These environments provide ample food sources and shelter from predators and strong currents. They frequently reside in structured underwater environments such as coral reefs, utilizing crevices, ledges, and small caves for resting. Their preferred habitats also include rocky areas, sandy bottoms, and seagrass beds, offering diverse foraging opportunities. Mangrove channels are another significant habitat, providing sheltered, nutrient-rich waters ideal for resting and hunting; they may also use shipwrecks or other submerged structures for cover.
Life within Their Habitat
Nurse sharks exhibit a nocturnal lifestyle, becoming active hunters primarily during nighttime hours, using specialized sensory organs like barbels near their mouths to detect prey hidden within the complex structures of their habitat. During the day, these sharks typically rest, often congregating in groups within sheltered spaces like under ledges, inside caves, or other protected spots. Their bottom-dwelling nature means they are well-adapted to navigating and utilizing the seafloor for both foraging and refuge, and they are known for their strong site fidelity, tending to remain in the same localized area for extended periods, rarely venturing far from their established home ranges. Their feeding habits involve suction feeding, allowing them to draw small invertebrates and fish, such as crabs, shrimp, and small bony fish, from crevices and sandy substrates. This feeding strategy is well-suited to the diverse prey found within their coastal habitats.