The Lemon Shark, known scientifically as Negaprion brevirostris, isn’t just any ordinary shark; it’s a unique and captivating creature of the coastal blue seas. With its distinct yellowish-brown hue, it stands out in the marine world. Along with the Sickle-Fin Lemon Shark of the Indo-pacific biogeographical region, these are the only extant species within the Negaprion genus.
The Lemon Shark is a type of Requiem Shark, large and bulky and can be found around the west coast of Africa, and the Americas, particularly around tropical and temperate coastal waters. They are big sharks, but as long as we give them their space and treat them with respect, they’re not generally dangerous. In fact, there have only been a few instances where they’ve ever nibbled on humans. So, if you ever spot one while diving or snorkelling, just remember they’re more curious than harmful!
Appearance & Characteristics of Lemon Sharks
Lemon Sharks are quite the sight. For a type of requiem shark, they are at the larger end of the scale. Larger than the Galapagos shark, but not as aggressive or threatening. Adults can stretch between 8 to 10 feet long (240 to 310 cm) and can tip the scales at a hefty 200 pounds. Rare examples have been known to reach almost double that!
Their yellow-brown or olive-gray skin is not just for show. It acts as a clever camouflage that helps them blend seamlessly with the sandy ocean floor. This shark boasts two dorsal fins that are roughly the same size, giving them a balanced look. Their snout, round and a bit short, gives them a distinctive blunt-nosed appearance. This unique combination of features makes the Lemon Shark easily recognizable among its peers.
It is estimated that the cruising speed of a lemon shark is around 2 miles – 3.2 kilometers per hr. They have electroreceptors on their head and in their dorsal fins, which can help them to detect the movement of prey fish.
Distribution – Location and Habitat
Warm, coastal waters are the Lemon Shark’s playground. They can be found as far north as New Jersey in the US to the sunny, coastal shores of Southern Brazil. They’re also frequent visitors to the Gulf of Mexico, the Caribbean, and the other side of the Atlantic Ocean around the west coast of Africa. While most common in the Atlantic, they can also be found in the eastern Pacific, particularly around the tropical and subtropical areas – the coasts of Mexico and Ecuador being hotspots.
They prefer subtropical shallow waters around coral reefs, mangroves, and bays. Interestingly, they often gather in groups near docks during the night time, only to retreat to the deeper waters during daylight. These type of shallow, warm waters offer great feeding grounds for the lemon shark. They can camouflage in the sandy and rocky shallows, to give them the upper hand on any approaching, unsuspecting prey.
The waters provide more than just favourable feeding grounds however. The shallow, warm waters also help to maintain the lemon shark’s metabolism – they need less energy to swim in warm water than they do in cold, deep water.
While they do spend most of their life in shallow, coastal waters, they have been found at depths as far as 92 meters, and during migration periods they are more likely to be found in open water. Some have even been known to venture into fresh water rivers, but never too far from the salty coast.
The Lifestyle & Behaviour of Lemon Sharks
While most sharks are known to use nursery areas for their young, lemon sharks use them for much longer than most other types of shark. These areas help the young to avoid predation, particularly from other adult lemon sharks which don’t seem to have any problem with cannibalism.
In general, these sharks are quite sociable, often forming groups, showcasing their preference for company over solitude. Their ability to learn from social interactions and cooperation with others is a driver to their preference to live in groups.
They have specific territories or areas they like to call home, returning to these familiar spots regularly and across generations.
During the day, it’s not uncommon to spot them lounging on the seabed in shallow water. Here, they patiently wait for small fish to approach and clean them. But this ‘resting’ state is deceptively draining and it actually requires more energy than their usual swimming!
The lemon shark will mostly eat at night, and evidence of pack hunting has been observed with the species. They tend to catch their prey by approaching at full speed, then breaking once they have the fish in their mouth. They will lunch to gain grip, and shake side to side to rip flesh apart when feeding. Once blood hits the water, others will arrive to take part in the feed.
Diet & Nutrition of Lemon Sharks
When it comes to food, Lemon Sharks have a diverse diet, but they do have their favourites. In prime environmental conditions they will pick their prey based on species and size, mostly the latter. As they tend to stick to their territories quite firmly, the diet does change, and depends on locally available species
Their menu ranges from bony fish (including eels, sea bass, flatfish, and stingrays, with fish making up the vast majority of their diet. In the Bahamas, where parrotfish and mojarras are common, these make up a large part of the diet for lemon sharks in this region.
In less favourable feeding grounds, they are known to also feed on crustaceans. Occasionally, they might indulge in a seabird or even a smaller shark. Adults are also known to feed on young lemon sharks when the opportunity arises and when other food is scarce. Their hunting strategy is simple – eat until satisfied. The rate at which they digest their food varies, depending largely on the quantity they’ve consumed and the temperature of their habitat.
Predators & Threats to Lemon Sharks
While the young ones need to be wary of bigger sharks, adult Lemon Sharks have few natural adversaries. However, the real threat comes from humans. They’re often caught for various reasons, be it for their meat, their fins, or their tough skin. Both commercial and recreational fishing of Lemon Sharks is common throughout their range, despite their declining numbers.
Lemon Shark Reproduction
Unlike many marine creatures but common amongst some species of shark (particularly requiem sharks) Lemon Sharks are viviparous. This means they give birth to live young, bypassing the egg stage. After a gestation period of 10-12 months, the mother shark seeks out shallow, safe waters to give birth.
A single litter usually has between 4 to 16 pups. The most pups ever recorded in a single litter is 18. These young ones stay in these protective nurseries for several years, gaining strength and size before venturing out to find their own mate. They don’t reach an age of reproductive maturity until they are around 12 to 16 years old. Males usually mature quicker and females will usually bear young once every 2–3 years.
Lifespan of Lemon Sharks
Life in the ocean is challenging, but Lemon Sharks have evolved to thrive. They can live for an impressive 27 years. They do most of their growing by the age of 6, but don’t reach sexual maturity until around double that. Throughout their life, they go through various stages, each with its own set of challenges and experiences.
Population and Conservation
The status of the Lemon Shark is a cause for concern. In 2020 the classification in the IUCN Red List was upgraded from ‘Near Threatened‘ to ‘Vulnerable‘ as populations continue to decline. Observations of the reducing population has been observed in regions like Florida. It is crucial now to monitor their numbers and ensure their survival.
5 Fun Lemon Shark Facts for Kids
- The record-holder for the biggest Lemon Shark was a massive 12.1 feet long!
- Their unique yellowish skin is a master of disguise, helping them hide in sandy waters.
- They can venture to depths of up to 300 feet. (91-92 meters).
- They return to the same nursery sites frequently and across generations.
- Despite their size, they’re not considered a significant threat to humans. And despite the name, they are not related to the lemon!
