Marine Life & Conservation Blogs
Sea Turtles rescued in Grenada during clean up
On Feb 20th twenty volunteers gathered for one of Eco Dive’s regular monthly clean up dives off Grand Anse Beach in Grenada, a shore dive site adopted by Eco Dive under the Project AWARE Adopt a Dive Site programme. With a mix of snorkelers, freedivers and scuba divers, including junior divers, the squad set out to find and recover as much ‘treasure’ as possible from the patch reef, sand patches and extensive seagrass beds skirting the beautiful 2 mile beach.
With a plan in place to cover as much of the beach as possible and focus on the high risk areas (storm drains, public jetty, public park accesses) the group set off. Divers were dropped by the dive boat up the beach in teams, a meeting time was set, mesh bags were issued and the they were off. Two more teams one of divers and a snorkel/freediving team headed off from the dive shop to cover the home base and down current zone of the beach.
With the clean-up underway the beach station was set up for sorting, counting and weighing of the haul. The debris gets sorted and the data recorded with Project AWARE to help track global trash trends and local hot spots and events. The first team back to the beach however was the freediving team, and they brought a VIP. Found tangled in kite line was a juvenile Green Sea Turtle. These juvenile turtles love this seagrass habitat off Grand Anse Beach and there is a rotating population of juveniles that join snorkelers regularly.
The team at Eco Dive are familiar with these endangered babies and work closely with Ocean Spirits, a local conservation organization, to tag and monitor these juveniles in the hopes of gaining more information on their movements, risks, health and a better estimate on the size of the local population. For anyone who has worked with a sea turtle project before you would know that catching a wild turtle is a stealth act of athleticism, especially juvenile Green’s who are deceptively quick when motivated. To see our snorkel team carrying a turtle (on a non-tagging day) had to mean something was amiss.
Sure enough timing on this clean up dive turned out to be serendipitous. This little turtle, later named Cora, was alive but exhausted. She had managed to tangle herself in a kite line and struggled so much that the line that immobilized her fore-flippers and dug cuts into her skin. Unable to reach the surface this little baby was struggling for her life, so she provided no resistance to rescuers as they freed her up to the surface and back to the dive shop for some TLC.
The right place right time nature of the day continued… with Ocean Spirits’ Director, Chair and veterinarian was on the clean up dive already, there were a further 5 veterinarians also on the clean up dive (it turns out vets love to help save the ocean and make great clean up dive buddies!) so little Cora was in good hands. Cora received some antibiotics to help prevent infection in her cuts, some fluids to help her relax and a safe place to stay for 4 days before her release safely back into the sea. Normally turtles would be tagged at the base of their fore-flippers to help identify repeat individuals and track growth etc however with the tissue damage and bruising Cora suffered under her fins on this occasion she was not tagged but marked with her name and well wishes on her shell and set free.
As for the trash clean-up dive the team successfully removed more than 38 kg of trash from the sea including 2 kites, 10+ kite lines, fishing line and lots of plastics and clothing. Juvenile octopus, mantis shrimp, cleaner shrimp, crabs, grunts, wrasse and gobies were found within the trash treasures and were released back to the sea by the sorting volunteers. Cora definitely stole the show and had all of the volunteers extra grateful for having made the effort to come out and join the clean up. More kite line remained in the sea however as some run for 100’s of meters. A plan was made by some particularly keen volunteers to come back during the week and target some of the known areas where kite line remained, the Eco Dive crew also committed to daily clean up dives for the week to get these lines out of the sea.
As the working week started, Eco Dive were back to their daily routine and booked a clean up dive with just 4 regulars for the next Friday morning. The divers were out for an hour and one of the dive teams found another turtle tangled. A different turtle, and a different kite line, but a very similar scenario. Kite line in the spring windy season is a known risk item that is found on the clean ups but a tangled turtle has never been found before until this week, and now they had rescued two! A call went out to Ocean Spirits saying “you’ll never believe me but ..” and the dive team got to work freeing the second turtle of the week from a fore-flipper straight jacket caused by kite line.
This juvenile green sea turtle, slightly bigger than Cora, was named Aurelia, after Eco Dive’s Junior Open Water Diver who is an adamant clean up diver and has been on a trash mission for weeks. Aurelia weighted in at just over 7 kg and was exhausted but safe.
Eco Dive’s tally for their clean up dives for the week: they removed over 50 kg of lines and plastic from the sea and rescued two baby turtles. A pretty good week all round!
For more information, or to join a clean up day, with Eco Dive Grenada visit their website by clicking here. You can also follow them on Facebook and Instagram.
In this series, the Shark Trust will be sharing amazing facts about different species of sharks and what you can do to help protect them.
Written by guest contributor – Yolanda Evans.
Mysteriously slithering around the dark mesopelagic of the western Pacific, the glorious Goblin shark swims in search for their next meal. This illusive shark is one of the most unique-looking sharks to ever exist, having a long snout called a rostrum and protrusible jaws, hailing them their common name, Goblin. Their rostrum is covered with small pores called the ampullae of Lorenzini, jelly-filled pores in the snouts of many sharks that are able to pick up changes in the electro-magnetic field, for example the muscle contractions of nearby fish. However, these pores can only detect movement only a few inches in front of the shark!
In addition to their rostrum, these sharks poses and amazing ability to protrude their jaws out or their cartilaginous skull by something called slingshot feeding. This is when the jaws are shot forward, extending 8.6-9.4% of the Goblin sharks total body length. However, this fast jaw action also creates a powerful suction-known as a pharyngeal suction-forcing their prey deeper into their mouths.
While many sharks range from greys to blues to browns, this stupendous shark can be a very pale pink! However, this unusual colour is not from a pigment in their skin, but from the thinness of their skin! Their skin has such a great transparency that the oxygenated blood that flows in their capillaries-tiny blood vessels-causes what would be their grey skin, to become pink. This amazing ability might actually been an adaptation for the shark, they live 270m-1300 m deep, red light wavelengths cannot be seen, making the spectacular shark near invisible to both prey and predators!
Their scientific name, Mitsukurina owstoni, comes from the British naturalist Alan Owston who is credited with discovering the shark, and from Kakichi Mitsuriki, the Japanese scientist who identified and described the shark. While the English common name is only from their long rostrum, the direst translation into Japanese is Tengu-zame, base of the Tengu, a Japanese mythological half-man-half-bird who had red skin and a long nose, a comparison more fitting.
Despite their somewhat intimidating appearance, the Goblin shark is not an aggressive species, predating on mainly small bony fish, crustaceans, and cephalopods. Long slender teeth that protrude out from their jaws, appearing almost like blades, are perfect for clutching onto their prey. Nonetheless, the most threat they create towards humans is disrupting our internet as they are known to bite down onto submarine cables!
Like many other shark species, Goblin sharks main threat is by-catch from deep-sea longlining and deep-sea trawling. They are listed by the IUCN as least concern. Unfortunately, being relatively understudied, this may be incorrect as there is a very minimal amount of knowledge about the lives of these sharks. Leaving the question: what else is there to know about the truly incredible Goblin shark?
SCIENTIFIC NAME: Mitsukurina owstoni
FAMILY: Mitsukurinidae
MAXIMUM SIZE: Up to 3.8 meters (12.5 feet) in length
DIET: Feeds primarily on deep-sea fish, but also crustaceans and cephalopods
DISTRIBUTION: Goblin Sharks have a wide but patchy distribution, found in deep waters of the Atlantic, Indian, and Pacific Oceans.
HABITAT: Primarily found in the deep sea, typically between 200 and 1,200 meters (656 and 3,937 feet) in depth. They are occasionally seen at shallower depths, but are typically associated with steep slopes and canyons on the continental shelf and slope.
CONSERVATION STATUS:
Due to their deep-sea habitat and elusive nature, they are rarely encountered and little is known about their population trends. However, they are sometimes caught as bycatch in deepwater fisheries, and there is concern over the potential impacts of deep-sea mining activities on their habitat.
Images – www.fishesofaustralia.net.au/home/species/3254 | Wikimedia Commons
A rare and mysterious species, the Megamouth Shark Megachasma pelagios was first sighted when one had gotten entangled in a sea anchor (Oceana, 2023), and hauled up by fishermen on-board a navy ship in 1976 (Black, 2014). The Megamouth Shark is distributed worldwide in tropical to temperate latitudes, can be found in costal to open ocean (epipelagic to bathypelagic), and is a filter feeder, like that of the Whale, and Basking Shark (Oceana, 2023).
Upon its first discovery, this genus of shark generated its own taxonomy, Order Lamniformes (mackerel sharks), and belongs to the family Megachasmidae (megamouth sharks) (Oceana, 2023). Currently this shark is listed as least concern on the IUCN Red List, with the most recent assessment of species health being in 2018 (IUCN Red List, 2023). The Megamouth Shark can be found resident in countries such as Australia, Sri Lanka, Vietnam, South Africa, and China, with the current population number of sharks being unknown due to their rare sightings, and lack of research (IUCN Red List, 2023).
A large species of shark, reaching weights of up to 2700 pounds (1215kg), and approximately 16 feet in length (5m), this species has only been observed within the wild a few times, with less than 60 individual sharks having been known by scientists to of ever been captured or observed (Oceana, 2023). The smallest of the three species of filter-feeding sharks, this shark derived its name from its remarkably large, circular mouth (Oceana, 2023). From what little research has been carried out on the species, from the rare few sightings these sharks have been observed residing near to the surface, in depths of up to 15,000 feet (4600m) (Oceana, 2023).
It is believed that Megamouth sharks only come near to the surface at night, spending the majority of their lives in the dark (Oceana, 2023). They are filter feeders that swim through the ocean with their mouths open capturing food resources, such as plankton (Oceana, 2023). The inside of their mouths contain light producing organs, believed to be used for attracting pelagic crustaceans and other prey (Oceana, 2023).
With commercial fisheries pushing to deeper depths to discover new species to market as food, more and more large deep sea creatures are being discovered (Oceana, 2023). Like other species of shark, megamouths mate via internal fertilization, giving birth to a small number of live young (Oceana, 2023). The adult shark does not connect to their live young through a placenta, and instead the mother provides an unfertilized egg during gestation (Oceana, 2023). Once born, the megamouth shark immediately becomes a filter feeder (Oceana, 2023). There is a huge lack in species behavioral ecology, and richness, and so electronic tagging studies and further research is needed in order to better understand, and to conserve this species (Watanabe & Papastamatiou, 2019).
SCIENTIFIC NAME: Megachasma pelagios
FAMILY: Megachasmidae
MAXIMUM SIZE: Up to 5.5 meters (18 feet) in length
DIET: Filter feeds for plankton, but also consumes deep water fish
DISTRIBUTION: Widespread distribution in tropical and temperate waters worldwide
HABITAT: Ocean-going. Surface to deep waters – 1,000m.
CONSERVATION STATUS:
Due to its elusive nature and rare sightings, little is known about its population size or trends. It is occasionally caught as bycatch in fishing gear, but there are no known directed fisheries for this species.
Banner image – Wikimedia Commons | GordonMakryllos
References:
- Black, R. (2014) A forgotten fossil megamouth gets a name. National Geographic. Available at: https://www.nationalgeographic.com/science/article/a-forgotten-fossil-megamouth-gets-a-name. Accessed: 21st March 2023.
- IUCN Red List. (2023) Megamouth Shark. IUCN Red List. Available: https://www.iucnredlist.org/species/39338/124402302#taxonomy. Accessed: 21st March 2023.
- (2023) Megamouth Shark. Oceana. Available at: https://oceana.org/marine-life/megamouth-shark/. Accessed: 21st February 2023.
- Watanabe, YY, Papastamatiou, YP. (2019) Distribution, body size and biology of the megamouth shark Megachasma pelagios. J Fish Biol. 95: 992– 998. https://doi.org/10.1111/jfb.14007
This month’s Creature Feature has a guest writer – Jodie Moore
WIN a c-monsta Wetsuit Hanger!!!
For this week’s competition, we’ve teamed up with c-monsta to give away one of their wetsuit hangers as a prize!...
WIN a Sharkskin Performance 40L Duffle Bag!!!
For this week’s competition, we’ve teamed up with our good friends at Liquid Sports to give away a Sharkskin Performance 40L Duffle Bag as...
Win a Vasili Lights Fish Lantern!
For this week’s competition, we’ve teamed up with Vasili Lights to give away one of their beautiful Fish Lanterns! Inspired...
WIN a Beuchat Maxlux S Mask and Spy Snorkel!!!
For this week’s competition, we’ve teamed up with our good friends at Beuchat to give away Maxlux S Mask and Spy Snorkel!...
-
News3 months agoDiving with… Ben Williams and Kay Van Leuven, Sunchaser Scuba, British Virgin Islands
-
News2 weeks agoPhilippines Fun-Size: Critters and macro life
-
Travel News1 month agoDiverse Travel expands Philippines portfolio
-
Marine Life & Conservation4 weeks agoThe Shark Trust Great Shark Snapshot is back!
-
News2 weeks agoJeff chats to… Christopher Bartlett, MD of Indigo Safaris, about scuba diving in St Helena (4 of 5)
-
News5 days agoPADI makes a splash at Palma International Boat Show
-
Marine Life & Conservation2 months agoDivers ask to take part in Easter Egg Hunt with a twist!
-
Marine Life & Conservation Blogs2 months agoCreature Feature – Megamouth Shark