Lemon shark – Negaprion brevirostris

The Lemon Shark, scientifically known as Negaprion brevirostris, is a species of requiem shark found in warm, coastal waters around the world.

Description and Characteristics

Lemon sharks are stocky requiem sharks with blunt, short snouts and an olive-brown to yellowish-brown dorsal side, with a lighter underside. Both dorsal fins are nearly equal in size and triangular; the first dorsal fin is positioned clearly behind the pectoral fins. Females typically reach about 2.4 m, males around 2.25 m in length, with rare specimens measuring 3–3.4 m. Notable features include their distinctive teeth (narrow and broad on the upper jaw, triangular on the lower) and the general absence of a spiracle behind the eyes. The yellowish coloration—especially along the flanks—gave the species its common name, “lemon shark.”

Habitat and Distribution

Lemon sharks inhabit tropical to subtropical coastal waters. In the Atlantic, they are found along the American coast from New Jersey to southern Brazil, including the Gulf of Mexico and the Caribbean; in the eastern Atlantic, they range from Senegal to around Angola. They are also present in the eastern Pacific—from the Gulf of California to Ecuador. Preferred habitats include shallow marine areas (usually ≤90 m) over sandy bottoms, seagrass beds, coral reefs, as well as nearshore mangroves and bays. They tend to form groups based on size and sex, often staying near piers at night and retreating to open waters during the day. Juveniles primarily grow up in shallow mangrove lagoons, which provide protection and abundant food.

Taxonomy

The lemon shark (Negaprion brevirostris Poey, 1868) bbelongs to the order Carcharhiniformes (ground sharks) and the family Carcharhinidae (requiem sharks). The genus Negaprion includes only two species: N. brevirostris (Atlantic, Gulf of Mexico, eastern Pacific) and the Sicklefin Lemon Shark (N. acutidens) in the Indo-Pacific.

Diet and Hunting Strategies

Lemon sharks are opportunistic predators. Their diet mainly consists of bony fish (e.g., blennies, mullets, trumpetfish, eagle rays), crustaceans (crabs, shrimp), and mollusks. Hunting mostly occurs near the coast. Field studies have identified two main strategies: juvenile sharks (up to ~2 m) inspect crevices for hidden prey (“substrate inspection”), while subadult and adult sharks attack schools of fish in the surf zone (“sardine blitz”). In general, they prefer to hunt in water less than 5 m deep, where they also form social groups. Adult lemon sharks have few natural predators, though cannibalism among individuals occasionally occurs.

Behavior

Lemon sharks display notable social behavior. They tend to gather in groups of peers and appear to form lasting bonds. Research shows that juveniles learn efficiently from each other by observing the behavior of conspecifics. Individual differences in temperament have also been observed. Another typical behavior is resting on the seafloor, actively pumping water through their gills to breathe. When resting, they swim slowly near the bottom. Although capable of long-distance movement, they usually remain in small home ranges. Many adult sharks return to their natal areas.

Reproduction

Mating typically occurs in late spring or early summer. After a gestation period of around 10–12 months, females give birth to live young (viviparous, with a yolk-sac placenta). Each litter consists of 4–17 pups (average 7–12), which are about 60–70 cm long at birth. Sexual maturity is reached at about 11–13 years. Females usually reproduce only every other year. Births take place in shallow mangrove lagoons, where dense root systems offer shelter from predators. Genetic studies show that females mate with multiple males and return to their own nursery grounds to give birth.

Threats and Conservation

According to the IUCN Red List, the lemon shark is classified as “Vulnerable.” Populations are declining in many regions, mainly due to human impacts. Major threats include overfishing, habitat loss, and low reproductive rates. Overfishing affects both targeted and bycatch scenarios. Mangrove forests—vital nurseries—are being destroyed for coastal development and aquaculture. Due to their late maturity and low reproductive output, populations recover very slowly.

Conservation Measures:

• Fishery Management: In the U.S., lemon shark catches are regulated by quotas and seasons; Florida has fully banned lemon shark fishing.
• Protected Areas: Large marine sanctuaries—such as the Bahamas Shark Sanctuary—safeguard key habitats.
• International Agreements: Lemon sharks are listed in Appendix II of CITES, regulating international trade.
• Research and Monitoring: Telemetry, genetic analysis, and long-term studies provide vital data for conservation planning.

Research and Discoveries

Lemon sharks are among the most extensively studied shark species. Long-term studies—such as those at the Bimini Shark Lab—have yielded valuable insights into their biology. Acoustic telemetry has shown a strong site fidelity in adults: many return annually to their birthplace. Molecular genetic studies confirm multiple paternities per litter and a return of females to their own nurseries. Behavioral and physiological studies frequently focus on this species, contributing significantly to global shark conservation strategies.

 

Description & Characteristics

Lemon Sharks are characterized by their distinctive yellowish-grey coloration, which gives them their common name. They are a medium-sized shark, reaching a maximum size of 340.0 cm. They are easily recognizable by their broad, flattened head, short snout, and prominent dorsal fins. Their bodies are robust and streamlined, adapted for efficient swimming. They have a relatively short, broad snout, which is slightly rounded and wider than the rest of their head. Their mouths are large, with rows of sharp, pointed teeth designed for capturing and tearing prey. They have a pair of prominent dorsal fins, with the first dorsal fin being significantly larger than the second. They also have a pair of pectoral fins, two pelvic fins, and a pair of anal fins. Their tails are powerful and well-developed, providing them with the necessary thrust for quick bursts of speed.

Habitat and Occurrence

Lemon Sharks are predominantly found in shallow coastal waters, typically in reef-associated habitats. They are commonly observed in bays, lagoons, and estuaries, where they can exploit diverse food sources. Their depth range spans from the surface to a maximum of 92.0 meters, making them a prominent presence in the subtidal, sublittoral, infralittoral, and deep zones of the oceans. They are commonly found in neritic zones, which encompass the coastal waters from the lower limit of the intertidal zone to the shelf edge at about 200 m water depth. This diverse habitat range allows them to thrive in a variety of environments, contributing to their successful distribution.

Taxonomy

The species Negaprion brevirostris belongs to the Class: Elasmobranchii, Order: Carcharhiniformes, and Family: Carcharhinidae. This classification places them within a large group of sharks known for their distinct features and diverse adaptations.

Feeding

Lemon Sharks are opportunistic predators with a varied diet, consuming a wide range of prey items. Their diet typically consists of:

• Big fish
• Edible crabs
• Lobster
• Sepia
• Small sharks

This diverse feeding strategy allows them to thrive in their varied habitats and exploit a wide range of food sources available to them.