Nurse shark Breeding Guide

In the Wild

Nurse sharks breed in warm, shallow coastal waters, typically during the late spring and summer months. Mating involves multiple males competing for access to a single female, often resulting in visible scars due to their mating behaviour, which includes biting the female’s pectoral fins to hold her in place.

• Reproductive Method: Ovoviviparous – the female retains eggs internally, where they hatch and the pups continue to develop before live birth.
• Gestation Period: Approximately 5 to 6 months.
• Litter Size: Up to 30 pups, each measuring around 30 cm at birth.
• Breeding Frequency: Females may only reproduce every other year due to the energy demands of gestation.

Pups are born fully independent and begin their lives in seagrass beds or mangrove nurseries, where they find protection from predators and access to small prey.

In Captivity

While rare, nurse sharks have been successfully bred in large public aquariums under carefully controlled conditions. These successes are significant due to the complexity of replicating the shark’s natural reproductive cues in a closed system.

• Requirements for Success:
• Massive tank systems (often tens of thousands of litres)
• Accurate photoperiod and temperature simulation
• Long-term observation and pairing compatibility
• Challenges:
• Ensuring the health and safety of the female during mating
• Managing aggressive male behaviour
• Raising pups in separate nursery systems due to their vulnerability

Most home aquarists and even private collectors do not have the space, knowledge, or resources to attempt breeding. In nearly all cases, breeding is left to institutions or conservation programmes.