Fish

Rich marine life at the French Frigate Shoals in the Papahānaumokuākea Marine National Monument.

Fish learn to stay within marine reserves–where it's safe

Researchers at the University of British Columbia (UBC) discovered that some fish have learnt to stay within marine reserves where they are safe from fishing, demonstrating the importance of such facilities. They made the discovery after modelling the movements of skipjack and bluefin tuna and great white sharks in the ocean.

New scorpionfish “Scorpaenodes barrybrowni.”

New Caribbean scorpionfish discovered

Researchers from the Smithsonian’s Deep Reef Observation Project (DROP) have discovered a new scorpionfish species off the Caribbean island of Curaçao. Inhabiting depths between 95 m and 160 metres, it is the deepest-living member of its genus found in the western Atlantic Ocean. “The 50-300 m tropical ocean zone is poorly studied -- too deep for conventional SCUBA and too shallow to be of much interest to really deep-diving submersibles,” said DROP lead scientist Dr. Carole C. Baldwin.

Racoon butterflyfish
Racoon butterflyfish

Fussy butterflyfish avoid corals touched by seaweed

A new study has revealed butterflyfish are particularly fussy about their food and shelter needs, avoiding corals that have come in contact with seaweed. Conducted by the University of Delaware, the study is the first to critically evaluate how coral-seaweed interactions will impact coral associated reef fishes, a key component of coral reef resilience.

Canadian eel tracked to Sargasso Sea

For the first time, Canadian researchers have tracked an adult female eel from Nova Scotia to the northern edge of the Sargasso Sea with a satellite tracker, a 45-day journey of 2,400 kilometres. For a century, scientists have been baffled as to how baby eels appear in the Sargasso Sea near Bermuda when adults have only been found in faraway places like Canada's St. Lawrence River.

A new species of the deep-sea ceratioid anglerfish
A new species of the deep-sea ceratioid anglerfish

New Deep-Sea fish species discovered

Adding to the list of deep-sea creatures, a Nova Southeastern University's (NSU) Halmos College of Natural Sciences and Oceanography researcher recently found a never-before seen species from the deep waters of the northern Gulf of Mexico.

The three females specimens found ranged in size from 30-95 mm in length. Looking at a photo of the fish, one quickly understands how anglerfishes get their common name.

The comeback kid? Schools of plaice in the North Sea and Skagerrak are the largest ever recorded.

Resurgence of North Sea fish stocks

Many years of restraint and restrictive fishing quotas seem to finally have paid off. Within a decade the stocks of spawning cod have almost doubled

Though levels of cod in the North Sea are not yet what they were pre-crisis, a remarkable recovery is well under way and advancing. Along with cod and plaice stocks of herring, haddock, hake, Norway lobster, common dab and witch (Torbay sole) are also improving .

Specimen photographed underwater in Arraial do Cabo, SE Brazil.

Invasive lionfish have now reached Brazilian waters

In an article just published in the open-access science journal PloS One, the first appearance of lionfish off the Brazilian coast has been reported.

The invasion of the northwestern Atlantic by the Indo-Pacific lionfish has developed extraordinarily fast, and is expected to cause one of the most negative ecological impacts among all marine invasions. Despite the anticipation that lionfish would eventually extend their range throughout most of the eastern coast of South America, it had not been recorded in Brazil until now.

Great White Shark can swim twice the speed other species

According to study leader Dr Yuuki Watanabe of the National Institute of Polar Research, Japan, "The physiological mechanism of keeping heat in the body is well understood. But, more a fundamental question is, why this unique evolution occurred in the first place. In other words, what kind of advantages does the fish gain from being warm-bodied?"

Adrenaline keep tuna hearts pumping during extreme temperature drops

Pacific bluefin tuna are unique amongst bony fish as they are endothermic (warm bodied) and can raise their core body temperature to 20°C above that of the surrounding water.

These animals are also capable of diving to depths of more than 1000 meter where the water is frigid. This chills the heart because it receives blood directly from the gills which mirrors water temperature. During deep dives their body temperature stays warm but their heart temperature can fall by 15°C within minutes. In other animals, humans included, this would stop the heart.