There’s little question that sharks are a number of the most extraordinary animals within the ocean – garnering large quantities of consideration from individuals around the globe. With roughly 450 species of sharks calling the underwater world house, there’s an unimaginable number of sharks to admire. However the admiration doesn’t should cease there, since sharks have roughly 650 ‘cousin’ species which might be equally superb.
All belonging to the scientific class generally known as Chondrichthyes, sharks and their kinfolk (chimaeras, skates, and rays) are characterised by their distinct skeletons made from cartilage, relatively than bone. With almost one quarter of Chondrichthyans categorized by the IUCN as Threatened with Extinction, divers play an important role in advocating for the protection of sharks and their relatives. That’s why we’re shining a shiny highlight on a few of shark’s closest (and coolest) kin.
Typically referred to as ghost sharks, chimaeras advanced roughly 400 million years in the past. With translucent eyes and a venomous backbone on their backs, chimaeras are largely confined to the deep sea at depths starting from 200 – 2,600 meters (650 – eight,500 ft). This sadly signifies that chimaeras are extremely weak to deep sea fishing pressures. Amazingly, some fortunate divers have once in a while noticed these other-worldly beauties at shallower depths.
Whereas they share many similarities with their shark cousins (cartilage skeleton, electroreception, and so on), chimaeras differ in three fundamental methods. As an alternative of getting 5 – 7 gill slits, chimaeras have four gills with one exterior gill overlaying (extra like bony fish). As an alternative of getting plenty of sharp and replaceable tooth, chimaeras have three pairs of everlasting grinding tooth plates. As an alternative of being coated in robust scales, chimaeras have clean pores and skin.
One group of shark relations which might be notably jaw-dropping for any diver fortunate sufficient to see them, are the shovelnose rays – together with guitarfish and sawfish. With their shark-like our bodies and cartilage skeletons, guitarfish and sawfish species have been first considered sharks. Later, they have been considered intermediates between sharks and rays. Newer findings from marine scientists have confirmed that this extraordinary group of animals are literally most intently associated to rays.
Sometimes discovered on sandy seafloors close to coastal seagrass beds and rocky reefs, shovelnose rays eat quite a lot of bottom-dwelling animals like shrimp, crabs, and small fish. With the power to pump water over their gills (like a few of their shark kinfolk), guitarfish and sawfish species are capable of stay immobile on the underside to stealthily cover from predators and prey. Regardless of their unimaginable traits, shovelnose ray species are among the many most threatened of all sharks and rays, primarily pushed by excessive demand for his or her fins.
Generally mistaken for stingrays, one group of shark kin which are typically ignored are the skates. Belonging to their very own distinctive household, a tremendous number of skate species reside all through the world’s oceans – from tropical waters all the best way to Arctic waters. Skates are additionally discovered at an unimaginable vary of depths from extraordinarily shallow waters to just about three,000 meters (10,000 ft) under the floor.
Skates sometimes have shorter, stockier tails than stingrays, with no stinger in any respect. These bottom-dwelling shark relations are available quite a lot of strong colours and patterns, in addition to quite a lot of sizes. The smallest skate species, the starry skate, grows to about 1/2 of a meter (2 ft), whereas the most important skate species, the widespread skate, grows to just about three meters (10 ft). Like their many kinfolk, widespread skates are sadly listed as critically endangered by the IUCN – typically caught for his or her fins or as bycatch in business fisheries.
Named for his or her capability to supply an astounding electrical shock, almost 70 totally different species of electrical rays are discovered worldwide in each heat and temperate waters. Most electrical rays bury themselves within the sand through the day and are available out to feed on small fish and invertebrates at night time – utilizing their two specialised electrical organs to shock and stun their prey.
Thankfully, because of the robust electrical discharge that every electrical ray is able to producing, these very round rays are principally not focused by any business fisheries. Divers most undoubtedly don't need to are available contact with an electrical ray, as their electrical shock is highly effective sufficient to knock down a human grownup instantly. In case you’re fortunate sufficient to identify one, as with all ocean animals, observing from a distance is right for everybody.
With greater than 200 species of exceptional stingrays inhabiting the world’s oceans (in addition to some freshwater rivers and lakes) stingrays are certainly sharks mostly recognized family members. Stingrays share many traits with their shark cousins together with cartilaginous skeletons, electroreception, and hard scales overlaying their our bodies. Like sharks, many stingray species are dealing with extinction since they're typically focused by business fisheries and caught as bycatch.
Stingrays get their identify from the sharp, typically serrated, toxin-filled barb on their tail. If a stingray feels threatened, it could carry its barbed tail upward and injure potential predators. That’s why it’s essential when doing a shore dive that divers do the ‘stingray shuffle’. By rigorously shuffling your ft whereas getting into and exiting the water, any stingrays hiding within the sand will transfer away earlier than you step on them. Uniquely, manta rays are the one members of the stingray household that shouldn't have stingers. Stingrays really are available all shapes, colours, and sizes – with the most important being the oceanic manta ray which may develop to 7 meters (23 ft) large.
Though sharks are the preferred of the Chondrichthyans, we really feel that it’s necessary to shine a highlight on the lesser-known (however equally superb) members of the shark household tree. Particularly as a result of one in 4 shark and ray species is dealing with an elevated menace of extinction.
Divers are a few of sharks and ray’s closest and most influential allies. Collectively, we're creating a strong collective voice to affect constructive change for this unimaginable group of ocean animals. Listed here are 4 methods you'll be able to assist:
- Enroll within the AWARE Shark Conservation Specialty Course. This diving course explores why sharks (and their closest cousins) are weak, the significance of a wholesome shark populations, and easy methods to take motion to guard them.
- Be aware of what finally ends up in your plate. Some shark and ray advocates select to take away ocean animals from their plate all collectively. Should you select to eat seafood, chorus from a purchase order until you may be sure that it’s coming from a sustainable supply with low bycatch ranges.
- Share your help for sharks and their kinfolk with others. Whether or not you begin a dialog with a good friend or member of the family, or submit about your ardour for sharks and rays on social media, each voice counts.
- Sign up to be a Torchbearer. Be a part of our group that cares deeply about therapeutic the planet above and under the floor. PADI Torchbearers encourage others to result in significant change by turning ardour into function for the ocean.