Last Updated on 02/18/2024

The basking shark (Cetorhinus maximus) is the second largest of all shark species, being the runner-up in the size contest that has the whale shark for winner. Its name derives from a peculiar behavior patters – these sharks are frequently seen swimming very slowly, having a good time basking in the sun. Unlike other large shark species, basking sharks love to spend time close to the surface of the water, and they also love taking long jumps out of it.

These large sharks can be found in temperate waters all over in the seas and oceans of the world. They prefer the surface of the water as well as the shallow areas around continental shelves. They are migratory species and they cover large distances following food.

The largest individual measured was found in the waters around Canada in 1851 – it was more than 12 meters long and weighed 10 tons. However, basking sharks do not typically reach that size – they normally measure 6-8 meters in length and weigh around 5 tons.
In terms of physical appearance, basking sharks look very similar to great white sharks, but they have a number of features that distinguish them. They have huge jaws, up to a meter wide and large gill slits that almost completely surround their head. Their teeth are relatively small, only 5-6 mm and they are hooked. Their snout is pointed and their skin is textured and covered in placoid scales and mucus.
Like all other sharks, basking sharks also have large livers – around one quarter of their entire body weight is taken up by the liver. The shark relies on this large liver for the continuous supply of energy it needs to keep moving and the liver is also known to produce oil that reduces the animal’s need to be constantly feeding.

Basking sharks belong to one out of the three plankton-feeder shark species. They are passive feeders, which means that they filter the water around to extract small fish, planktons and tiny invertebrates. They filter around 1,800 tons of water an hour to cater for their huge energy needs. They can push the water through their gills only when they are moving – therefore, they are continuously in motion.

Basking sharks are ovoviviparous, which means that the fertilized eggs are kept inside the mother’s body until the embryos are sufficiently developed to be able to survive outside on their own. While inside the eggs, the embryos rely entirely on the yolk sac for nutrition, there is no placental connection between them and the mother. The length of the gestation is not known. Some researchers think it lasts for about a year, while others say it can last up to two, even three years. The juveniles are around 1.5-2 meters long when they are born. The basking shark is a long-lived creature – both males and females reach sexual maturity between the age of 6 and 13 and they live for about 50 years on average.

Unveiling the Gentle Giants: An Insight into Basking Sharks

Dive into the enigmatic world of the Basking Shark (Cetorhinus maximus), a creature that effortlessly combines grandeur with mystery. As the second-largest living fish, following the whale shark, these gentle giants roam the temperate oceans, captivating the curiosity of marine enthusiasts and scientists alike. Despite their formidable size, basking sharks are filter feeders, leisurely swimming with their enormous mouths wide open to feast on plankton. This intriguing juxtaposition of their immense size and docile feeding habits makes them a fascinating subject for exploration.

Anatomy and Physiology of the Basking Shark

The Unique Feeding Mechanism

Basking sharks possess a distinctive gill raker system in their cavernous mouths, which enables them to filter plankton from the water. As they glide through the ocean, water enters their mouth and passes over the gill rakers, trapping tiny organisms. This feeding strategy is known as passive filter-feeding and is highly efficient, allowing these sharks to consume up to thousands of tons of plankton during the feeding season.

Adaptations for a Pelagic Lifestyle

The basking shark’s hydrodynamic body shape and large caudal fin provide it with the necessary propulsion to traverse vast stretches of open water. Their skin, covered in tiny placoid scales, reduces drag and protects against parasites and other injuries. These physiological adaptations are crucial for a pelagic (open ocean) lifestyle, enabling the basking shark to undertake extensive seasonal migrations in search of plankton-rich waters.

Habitat and Migration Patterns

Seasonal Migrations in Search of Plankton

Basking sharks are highly migratory, following plankton blooms that vary seasonally across temperate seas. Their migrations are a marvel of nature, often spanning thousands of miles. Satellite tagging has revealed intricate patterns in their movements, showing a preference for surface waters during feeding periods and deeper waters at other times, possibly for breeding or avoiding harsh weather conditions.

Preferred Habitats and Global Distribution

These sharks favor the temperate waters of the Atlantic and Pacific Oceans but are also found in the Mediterranean Sea and around New Zealand. Their distribution is closely tied to the availability of plankton, making them common visitors to coastal areas during bloom seasons. Understanding the habitat preferences of basking sharks is crucial for studying their behavior, population dynamics, and the effects of climate change on their migration patterns.

Behavior and Social Structure

Solitary Giants with Seasonal Socializing

Contrary to popular belief, basking sharks can be quite social during peak feeding times, forming groups to efficiently exploit plankton patches. Outside of these feeding aggregations, they are mostly solitary, roaming the vast oceans alone. This duality in their social behavior is a fascinating aspect of their ecology, shedding light on their complex life strategies.

Breeding Mysteries and Lifespan

Much about the breeding habits of basking sharks remains shrouded in mystery, with few observations of their mating rituals. What is known, however, is that they are ovoviviparous, meaning embryos develop inside eggs that are retained within the mother’s body until they are ready to hatch. The longevity of basking sharks is equally intriguing, with estimates suggesting they can live for up to 50 years, a testament to their resilience and adaptability in the marine environment.

In conclusion, basking sharks are remarkable creatures that embody the beauty and complexity of marine life. Their gentle nature, coupled with their impressive size and unique feeding habits, makes them a subject of endless fascination. By delving into their anatomy, migration patterns, and behavior, we gain insights not only into their world but also into the broader workings of our oceans. As we continue to uncover the secrets of these gentle giants, we are reminded of the wonders that lie beneath the waves, waiting to be discovered.

FAQs About Basking Sharks

1. What do basking sharks eat? Basking sharks are filter feeders, primarily consuming zooplankton, small fish, and fish eggs. They swim with their mouths wide open, filtering these tiny organisms through their gill rakers.
2. How big can basking sharks get? Basking sharks can reach lengths of up to 12 meters (about 39 feet), making them the second-largest fish species, only surpassed by the whale shark.
3. Are basking sharks dangerous to humans? Despite their large size, basking sharks pose no threat to humans. They are gentle giants, focused solely on filtering plankton from the water and generally indifferent to human presence.
4. How do basking sharks reproduce? Basking sharks are ovoviviparous, with embryos developing inside eggs within the mother’s body until they hatch. However, much about their breeding behavior remains unknown due to the difficulty in observing these deep-sea creatures.