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By Raquel Gilliland; Sea of Change Intern

Our “Creature Feature” is back again for another week of education and conservation surrounding another mysterious sea creature! This week’s animal has the word “fish” in its’ name, but some people say it looks more like a shark; however, this week’s creature is actually a ray! Our confusing creature of the week is the famous sawfish, or carpenter sharks. There are five species of sawfish, the Queensland sawfish (Pristis clavata), the smalltooth sawfish (Pristis pectinate), the common/largetooth sawfish (Pristis pristis), the narrow sawfish (Anoxypristis cuspidate) and the narrowsnout/green sawfish (Pristis zijsron).

Easily identified by their long flattened nose, or rostrum, they were once abundant throughout the Atlantic Ocean the Indo-Pacific Ocean. Their current conservation status has taken a drastic turn in the past few decades due to habitat loss, bycatch, and overfishing; all five species are now listed as either endangered or critically endangered on the IUNC Red List of Threatened Species. Their long rostrums were prized not just in the recreational fishing community, but also in many ancient cultures and mythology. In what is currently Mexico, the ancient Aztecs depicted the rostrum being used as a weapon/sword and sawfish teeth have been found in Mayan graves. In Panama, sawfish were thought of as powerful spirits that could offer protection against supernatural enemies. They were even used as a modern symbol in WWII on navy ships and submarines.

Although they were once revered, these special rays are facing many challenges to their survival. Sawfish fins are among the most prized and expensive exports for shark fin soup, which is considered a delicacy in many Asian countries, yet adds no taste or health benefits. As with many other sharks and rays, sawfish parts are often advertised as traditional Chinese medicine, but no medical benefits have ever actually been proven. Their teeth are sold and used for cockfighting spurs in Peru and Ecuador. And sadly their rostrums are sold as a novelty item to tourists in many countries.

What’s happening to save these creatures? In 2007, all five species were listed on CITES Appendix I, which prohibited the harvest and trade of all sawfish and their parts. Unfortunately, people are still illegally catching and selling sawfish all over the world, it is easy to identify their rostrums, but difficult to identify their fins in the fish markets.

One of the largest sawfish conservation projects is currently happening in Florida at the Florida Museum of Natural History, which maintains the International Sawfish Encounter Database where people can submit information about a sawfish encounter or sighting, whether it’s alive or a rostrum hung on a wall. Next time you encounter a sawfish get online and let them know! Also get to know your favorite shark/ray conservation team and get involved in any way that you can with donating, becoming involved in local campaigns, and making sustainable lifestyle choices!

By Breilly Roy; Sea of Change intern

Welcome to our fifth “Creature Feature!” Each week we briefly introduce you to some fascinating facts about a sea creature, why it is special and unique, and its conservation status. This week’s creature is the star of a song written by the band Heart and has one of the most daunting smiles in the ocean. Any guesses? It’s the great barracuda!

The great barracuda (Sphyraena barracuda) is known for its long body shape. Having an elongated torso, it looks like an underwater missile. This streamlined body shape allows the fish to move quickly underwater. They have been documented to swim in bursts up to 35 miles per hour! Not only does their speed help them escape hungry predators, but it aids in their hunting. Of course, their ferocious looking mouth also plays a big role in catching prey, though their vicious reputation is unwarranted – as with most sea creatures, if we respect them, they’ll do the same for us.

Unlike most fish, the great barracuda has two sets of teeth. Along the outside of the top jaw sits a row of smaller teeth, and behind them are dagger-like teeth. The bottom jaw houses long, needle-like teeth. Having dentition like this not only prevents the escape of prey, but it allows this top predator to grasp, tear, and cut up its catch before consumption.

As an adult they exhibit a nonsocial lifestyle, often hovering solitarily above coral reefs or wrecks looking for prey and defending their territory. Although, the great barracuda has been known to attack divers, such instances are rare. Some believe it is due to the species being attracted to a shiny object on a diver – so divers are warned to not wear watches or jewelry as a reflection might resemble the silvery fish the barracuda prey on. This species may seem scary, if you keep your distance, you have nothing to fear. The global conservation status of the great barracuda is of least concern according to the IUCN Red List. This species may seem intimidating, but when admired from afar one realizes the barracuda is an amazing fish that plays a vital role in its ecosystem.

By Raquel Gilliland and Breilly Roy; Sea of Change Foundation interns

Welcome to our fourth “Creature Feature!” For those of you joining us for the first time, each week we briefly introduce you to some fascinating facts about a sea creature, why it is special and unique, and its conservation status. This week’s creature is a distant relative of the snail and a master of disguise. Have you figured it out yet? It’s the common cuttlefish!

Cuttlefish belong to the phylum Mollusca which consists of organisms such as snails, clams, scallops, oysters, octopuses, and squid. One common feature of this particular phylum is that all members have/had some form of exoskeleton or shell. As these creatures evolved, some lost their shells. Cuttlefish have the remnants of this body armor, but it is located inside their bodies and is called the “cuttlebone.”

These cephalopods, which means “head foot” in Greek, are unique in that they can camouflage themselves with their environment, much like a chameleon. Unlike the reptile though, the cuttlefish can change not only it’s skin color but it’s texture as well. This expert camouflage is carried out by two different types of specialized cells, papillae cells for texture and chromatophores for color.

Beyond their unique skin, cephalopods are also known for their high intelligence levels. Cuttlefish have brain cells that are similar to humans. Using this information, scientists have learned more about how the human brain operates and hope to apply that knowledge to find cures for diseases.

Thankfully, this species (Sepia officinalis) is considered an organism of least concern according to the IUCN Red List. If their habitat is protected, these creatures should inhabit the oceans for thousands of years to come.

By Raquel Gilliland and Breilly Roy; Sea of Change Foundation interns

Welcome to our third “Creature Feature!” Each week we briefly introduce you to some fascinating facts about a sea creature, why it is special and unique, and its conservation status. This week’s creature is the graceful hawksbill turtle. These underwater reptiles belong to the family Cheloniidae. Turtles in this family are the only known turtles that have front limbs stronger than their back.

Hawksbill turtles can be found throughout the tropical oceans of the world, usually occupying coral reefs. As these animals are predominantly spongivores (they eat sponges), their narrow, pointed beaks, resembling that of a hawk, are a useful tool in removing the invertebrates from clefts in the reef.

In 2015, a hawksbill was found near the Solomon Islands during a night dive, but this was no ordinary reptile as this turtle glowed in the dark! Scientists determined that this female was exhibiting signs of biofluorescence. Unlike bioluminescence, biofluorescence is not a chemical reaction within an organism but rather an organism absorbs light and projects it as a different color.

Sadly, hawksbill turtles are listed as critically endangered by the IUCN Red List and are decreasing in numbers. Due to their uniquely decorated shells, they are often harvested illegally and sold around the world despite their protection under CITES (Conservation on International Trade in Endangered Species of Wild Fauna and Flora).

With proper conservation and preservation methods put into practice, such as reducing light pollution, plastic pollution, and nesting beach conservation, this ancient species has the potential to recover its declining populations.

By Raquel Gilliland and Breilly Roy, Sea of Change Foundation interns

Welcome to another “Creature Feature” where we briefly introduce you to some fascinating facts about a sea creature, why it is special and unique, and its conservation status. This week’s creature is the amazing thresher sharks. They belong to the class Chondrichthyes (sharks, rays, skates, and chimaeras) comprised of fishes that have skeletons made of cartilage rather than bone. The three species of threshers (Alopias spp.) stand out among sharks or elasmobranchs with their unique tail, or caudal fin, that can be as long as their body.

Their habitats are primarily pelagic, meaning open ocean, and they often travel into shallow coastal waters when hunting large schools of fish. They feed mainly on juvenile tuna, bluefish, and mackerel. They use their long tails to slap schools of fish thereby herding and stunning their prey. As with many species of sharks, they are vital apex predators helping to keep our oceans healthy.

According to the IUCN Red List, the common thresher shark is “vulnerable” to extinction with decreasing population trends. These negative trends are most likely due to their low reproductive rate and the effects of overfishing often driven by demand for shark fins for Asian markets and restaurants. In 2017, the common thresher shark was added to CITES Appendix II providing some protection from international trade in its parts including fins.

Given sharks’ vital role in marine ecosystem health and that many shark species are threatened by overfishing and habitat loss, the Sea of Change Foundation supports research that can help protect sharks. In 2017, with our partners Ocean First Institute, ConnectOcean, and the University of Costa Rica – CIMAR, we helped fund and launch the first-ever shark and ray assessments at Las Catalinas, Costa Rica, an area where sharks have likely been overfished. In 2018, the Foundation will continue to support research and conservation in the Guanacaste region of Costa Rica focused on sharks and rays.

Please consider supporting the Sea of Change Foundation as we focus our efforts on threatened species and habitats and work to create positive change for the oceans we all love to dive and explore. DONATE HERE. Thank you.

By Raquel Gilliland and Breilly Roy, Sea of Change Foundation interns

Welcome to our new series “Creature Features” where we’ll briefly introduce you to some fascinating facts about a sea creature, why it is special and unique, and its conservation status.

This week’s creature is the long-spined or black sea urchin (Diadema antillarum), a sharp specimen that hides in small crevices along the reef. They belong to the phylum Echinodermata – exclusively marine invertebrates that are characterized by a hard, spiny covering or skin, and that also includes other familiar reef residents such as sea stars, sand dollars and feather stars. They have a test or “shell” with venomous spines that grow as long as 10-12cm. Their ventral (underneath their bodies) scraping mouths were originally described by Aristotle as being lantern-shaped and scientists today still refer to them as “Aristotle’s lantern”.

Their habitats are crevices in coral reefs at depths of 1-10 meters deep. These creatures are nocturnal and feed mainly on algae; and they, in turn, are a favorite food of queen triggerfish (Balistes vetula) that use their powerful jaws to pull out the spines and break the test. The urchins’ role in a healthy reef ecosystem is to graze on algae that otherwise can outcompete corals for limited space to settle and grow. Unfortunately, in the early 1980’s there was a significant die off of long-spined urchins due to disease with 90% of the species being wipe out throughout Florida, the Caribbean and Bermuda from which many reefs in the region are still recovering.

Given that Diadema produce many eggs, their slow recovery from the disease outbreak almost 30 years ago has long puzzled scientists. Recently, researchers from Scripps Institution of Oceanography found that when staghorn coral (Acropora cervicorni) – a threatened species on the U.S. Endangered Species List – populations increase, Diadema populations decrease. They theorized that the reason for this could be the aggressive and territorial behavior of the threespot damselfish (Stegastes planifrons) that competes with Diadema for algae grazing patches on the reef. “These damselfish pick up urchins and move them off the coral with their mouths,” said Cramer, a postdoctoral scholar at Scripps and lead author of the study. “Damselfish populations appear to have grown recently as their predators have been overfished, which is one plausible explanation as to why long-spined urchin populations have failed to recover.”

Currently, the global conservation status of these urchins has not been evaluated by the IUCN (International Union for the Conservation of Nature) Red List, they have no special status under the U.S. Endangered Species Act, and under CITES (the Convention in International Trade in Endangered Species) they are also not protected from collection nor international trade.

Given their vital role in coral reef recovery and resilience, we hope to see populations of important reef grazerscome back in full force. You can learn more about how the Sea of Change Foundation has helped support research to reintroduce long-spine sea urchins to the reefs of the Bahamas, here; Reversing the Decline of Bahamian Coral Reefs – Herbivory Study, 2018.

Please consider supporting the Sea of Change Foundation as we work to create positive change for the oceans we all love to dive and explore. DONATE HERE. Thank you.