The lemon shark, otherwise known as Negaprion brevirostris in the scientific community, is just one of the over 1,000 species of shark you can find across the globe. Because of potentially depleting population sizes, the lemon shark is currently considered “Near Threatened.”
Characteristics and Appearance
At birth, lemon sharks measure about 20 to 30 inches long. The pups stay at their nursing grounds with their litters (which can range from 4 to 17 members) for years before growing to their adult sizes.
Lemon sharks are sexually dimorphic—that is, you can tell if a given shark is male or female by looking at it. Male and female are lemon sharks are similar in appearance, but there is a slight distinction that makes each sex identifiable at a glance.
Weight and Length
Female lemon sharks tend to be 94 to 96 inches long at maturity, while males are generally 90 inches long. However, individual lemon sharks can be longer than these averages. Some of them can measure over 120 inches long, for instance. Both sexes weigh the same—approximately 406 to 551 pounds.
Physical Characteristics and Color
Lemon sharks’ skin is olive to yellow-brown, and their underbellies are light yellow. That is where they get the name “lemon sharks.” They have no unusual markings on their bodies.
One of the lemon sharks’ most defining characteristics aside from their coloring is their dorsal fins. The first dorsal fin is located on the mid-back, and the second one is closer to the tail. While the second fin is shorter than the first, they have the same triangular shape.
Another remarkable characteristic of the lemon shark is its snout. A lemon shark’s snout is blunted and is narrower than the shark’s mouth.
Lifespan and Reproduction
Lemon sharks live an average of 27 years in the wild, though they can live past 30 in some cases. They practice polyandry—female lemon sharks take on multiple male partners in their lifetimes. Scientists believe female lemon sharks keep sperm from their various partners and have these mixed sperm compete simultaneously for a place in an egg. To deposit sperm, male lemon sharks will bite a female’s front fins before inserting their claspers into the females’ cloacas.
Once a female has conceived a litter, she will gestate for 10 to 12 months before swimming to a shallow nursery ground and birthing her pups live. The pups will live in these grounds for 2 to 3 years or when they become about 3 feet long. However, they do not mature fully until the ages of 12 or 13. Young lemon sharks can and will hunt for their own prey.
Lemon shark breeding happens during spring and summer. Females return to the same nursery grounds year after year and take a year-long break between litters.
Researchers don’t know much about the integration of maturing lemon sharks into adult waters. However, researchers do know lemon shark pups will stay near their birthing grounds for years after leaving the immediate area.
Lemon sharks live in oceanic waters no deeper than 188 feet. They live around reefs, bays, mangroves, and docks. These areas are amenable for when female lemon sharks give birth to their young.
Though lemon sharks are primarily ocean creatures, they have been known to venture into freshwater locations, like river mouths. However, they do not tend to go very far into these waterscapes.
Where Do Lemon Sharks live?
You can find the lemon shark in coastal regions all over the world. They are most populous in the Gulf of Mexico, the West Indies, and the Caribbean. Sizable populations exist along the Brazilian coast, the Mexican peninsula, and the eastern United States, too. You can even find them along the west coast of Africa.
Food and Diet
When lemon sharks hunt, they swim along the bottom of the waters they inhabit. They will eat until they are no longer hungry, which means the amount of food they eat in one feeding will vary. Likewise, how long it takes for them to digest their food varies.
What Do Lemon Sharks Eat?
Lemon sharks will eat all sorts of sea animals, including insects. With that in mind, though, lemon sharks especially love eating fish, shellfish, and mollusks. Some of their typical prey include:
- Brown crabs
- Eagle rays
As well, baby lemon sharks are known to eat prawns and shore crabs. Moreover, adult lemon sharks will sometimes eat their babies.
Threats and Predators
Nature does not toy with the lemon shark. While they do face some threats, they are near the top of the food chain.
Though lemon sharks are not yet “Threatened,” humans do pose a threat to lemon sharks. Humans prize this species for its culinary, medical, and research value. When humans go too far hunting in these areas, we risk overhunting the lemon shark.
Human activity indirectly harms lemon sharks, too. Mangroves, for instance, are a large lemon shark habitat currently threatened by human agricultural and industrial development. As well, lemon sharks can become tangled in nets used by industrial fisheries. This sad fact holds even if these fisheries are not intentionally hunting lemon sharks.
Climate Change and Global Warming
Though lemon sharks are dominant forces in the sea, they are not immune to climate change and its impacts. Specifically, they face significant challenges when it comes to habitat.
Climate change is bleaching and destroying coral reefs, one of the lemon sharks’ favored living and breeding spaces. As reefs die out, lemon sharks lose a habitat. This fact means they also lose an area to breed.
Climate change also threatens to destroy mangroves. As with the destruction of reefs, this trend has the potential to threaten lemon shark populations.
The adult lemon shark has no known predators. Some other shark species will prey on baby lemon sharks, but those same species will not pursue adults.
Indeed, because of the cannibalization of its young, one of the lemon shark’s greatest predators may be itself.
Flukes, tapeworms, and other parasites use lemon sharks as hosts. While these parasites do not pose a significant threat to lemon sharks as a species, individuals whom parasitic species have chosen as hosts are in danger of injury or worse.
The Florida Fish and Wildlife Conservation Commission prohibits the harvesting of lemon sharks in state waters. Any lemon shark that catches onto a hook is to be released immediately, either by removal of the hook from the shark or by cutting the shark free—whichever will release the shark quickest. Florida adopted this regulation in 2010.
The IUCN (International Union for Conservation of Nature) classifies the lemon shark as “Near Threatened,” citing decreasing population numbers as a possible hazard to the species’ future.
Fun Facts About Lemon Sharks
- People throughout the world have named the lemon shark for its distinctive skin. Interestingly enough, though, the German language has two names for the lemon shark: “zitronenhai” (“lemon shark”) and “kurznasenhai” (“short-snout shark”). Interestingly, in Spanish, the lemon shark is known as the “tiburon galano” (“gallant shark”).
- Although lemon sharks are fearsome predators among sea life, they pose very little threat to humans. As of 2011, researchers had found only 10 cases of lemon sharks attacking humans, and none of these cases were deadly.
- Lemon sharks have a symbiotic (that is, mutually beneficial) relationship with attached remoras (otherwise known as sharksuckers). The remoras hang onto lemon sharks’ bodies and eat any mess left by the sharks while they feed. In turn, the lemon sharks get a skin cleaning, which keeps them free from infections.
- While mother lemon sharks do most of the parenting, father sharks will get involved after the young are born.
- Lemon sharks tend to move and live alone.
- They are active most of all in the early morning and evening.