…is a species of rough shark found throughout the eastern Atlantic, from Norway all the way down to South Africa. Unlike other rough sharks this species has ridges over its eyes, these ridges extend to knobs which are covered with scales. Angular roughsharks are usually found on muddy or algal bottoms of continental shelves where they feed on invertebrates like molluscs and arthropods.
Great White Sharks Gorge Together on Dead Whale Blubber
by Becky Oskin
Great white sharks feast together on dead whales, which are important food resources for the normally solitary predators, a new study finds.
Drawn by wind-blown slicks of chemicals from decomposing flesh, great white sharks measuring up to 16 feet (5 meters) long gathered at floating carcasses near South Africa’s Seal Island, gorging on blubber, researchers found during observing trips in 2000-2010. These giant sharks rarely appear near the coast but may cruise nearby, waiting to pounce on dead or dying whales, the researchers said.
“These massive sharks come in pretty quickly — within less than 24 hours,” of a dead whale’s arrival, said study co-author Neil Hammerschlag, a marine ecologist at the University of Miami. “We hypothesize these animals are cruising the coastline to take advantage of these types of situations.”…
Photograph by Ralph Lee Hopkins, National Geographic
This photo was originally labelled as a “Manta Ray”, but these leaping rays are in fact closely related Mobula rays. They are most famous for their habit of leaping far out of the water off the Pacific coast of Mexico.
A whale shark (Rhincodon typus) opens its huge mouth as fish hitch a ride on its back in Azores, Portugal. As you probably already know, the whale shark is the largest species of “fish” currently in existence.
Gray reef sharks (Carcharhinus amblyrhynchos) are known for being active at night. They are considered Near Threatened by the IUCN Red List due to fishing and the loss of their coral reef habitat. The sinister animal, with its sleek body, can be quite aggressive when directly threatened.
Want to travel the oceans alongside great white sharks, but your busy schedule and fear of death always seem to get in the way? There’s an app for that.
Now anyone with an iPhone or an iPad (and $3.99 to spare) can follow along in near-real time with a dozen of the world’s most iconic predators with the app Expedition White Shark.
“We’re hoping it raises public awareness about white sharks, which helps our conservation efforts,” said marine biologist Michael Domeier, the man behind the app and president of the Marine Conservation Science Institute, a small, California-based nonprofit research organization.
Domeier has studied great white sharks for many years, and was one of the first people to ever outfit adult great white sharks with satellite tracking tags — the key to the new app. His adventures were chronicled on the National Geographic Channel program “Shark Men.”…
Great White Sharks Eat Far More Than Previously Thought
Great white sharks, the world’s largest predatory fish, eat three to four times more food than previously thought, an Australian study shows.
U.S. research from the 1980s estimated a 30-kilogram, or 66-pound meal of mammal blubber could sustain a one-ton shark for more than six weeks. That perpetuated assumptions that large sharks could survive long periods without eating.
However, a University of Tasmania-led study published this week in Scientific Reports on the nature.com website found that 30 kilos was only enough for 12-15 days. Researchers tagged a dozen great white sharks at Neptune Islands off South Australia and calculated their metabolic rate derived from swimming speeds.
They worked out how much energy the sharks burned and how much food they required. Senior research scientist Jayson Semmens, lead author on the study, said the amount of energy required by great white sharks was equivalent to eating a seal pup every three days…
In counter-illumination, the lanternsharks, like many deep-sea animals, light up their undersides in order to disguise their silhouette when seen from below. Brighter bellies blend in with the light filtering down from the surface.
Fishing the 2-ft-long (60-cm-long) lanternsharks up from Norwegian fjords and placing them in darkened aquarium tanks, the researchers noticed that not only do the sharks’ bellies glow, but they also had glowing regions on their backs…
Also known as the devil fish, the giant devil ray is a species of mobula ray (not a manta) native to the Mediterranean Sea and Eastern Atlantic. As its common name suggests this species is the largest in the genus mobula with individuals reaching a length of up to 17 ft long. Like other mobula species these large rays spend most of their time in the open ocean feeding on plankton and small fish. Sadly this species is in decline as accidental catching by fisherman has caused this species to be listed as endangered.
CITES Ruling on Shark Protection - What Does it Mean?
Shark Trade to be Regulated to Curb Overfishing
by Megan Gannon
Conservationists voted today (March 11) to regulate the international trade of five species of sharks that are threatened by overfishing and targeted for their valuable fins.
Oceanic whitetip sharks, porbeagle sharks, scalloped hammerheads, great hammerheads, and smooth hammerheads — as well as two species of manta rays — are all set to get new protections after today’s votes at the meeting of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) in Bangkok.
If the proposals are upheld at a plenary session later this week, all seven animals will be listed under Appendix II of the CITES Treaty, which includes species that may become threatened with extinction if they are traded unsustainably. So far, basking sharks and great white sharks are the only species of elasmobranch (a family that includes sharks, rays, and skates) listed on Appendix II…
“ Sharks and manta rays have received protection today under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). CITES member nations, referred to as “Parties,” voted to increase protections for five species of sharks as well as two species of manta rays. Leading up to and during this meeting, the United States has worked with a coalition of countries committed to gaining support for these proposals…
In addition to oceanic white tip sharks, proposals to increase protection for three species of￼ hammerhead sharks – scalloped hammerhead, great hammerhead, and smooth hammerhead;￼￼ porbeagle sharks; and manta rays were adopted by the Parties…”
Sharks Get Protection at the CITES Convention in Bangkok
After two hours debate, member countries of CITES accepted in Committee I of CoP16 the proposal submitted by Brazil, Colombia and the United States of America to include the oceanic whitetip shark (Carcharhinus longimanus) in CITES Appendix II by a secret ballot of 92 support, 42 against, and 8 abstentions, i.e. a 2/3 majority.
The United States will support proposals at CoP16 (the international conservation convention meeting in Bangkok) to restrict unsustainable levels of international trade on manta rays and five shark species—porbeagle, scalloped hammerhead, great hammerhead, smooth hammerhead, and oceanic whitetip. Populations of the five shark species are declining because of demand for fins for food products such as soup and medicine, while manta rays are being overharvested to meet demand for their gill plates.