Fish

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.

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.

Great Barrier Reef potato cod at risk from own friendliness

Potato cod in Queensland are at risk and their placid and curious nature appears to be playing a major part. The Great Barrier Reef Marine Park Authority (GBRMPA) is investigating reports that illegal fishing and fish 'framing' are responsible for declining potato cod numbers at the Cod Hole, a popular dive site off Lizard Island.

This image shows the new trout species Salmo kottelati.

A new species of trout discovered in Turkey

In order to understand the rich genus diversity in Turkey, a group of researchers from Recep Tayyip Erdoğan University, Faculty of Fisheries collected samples from more than 200 localities throughout the country between 2004 and 2014. The resulting paper, published in the open access journal ZooKeys, focuses only on the Salmo species distributed in the Alakır Stream drainage, from where the new species was described. It as named Salmo kottelati after Maurice Kottelat, who contributed to the knowledge of the fish fauna of Europe and Asia.

Anthias (filephoto) - one of the species used in the experiment

Fish need to decompress too

According to CAS’s Matt Wandell the chamber is fairly simple in design and can bring a fish up to to surface pressure in around 20 hours or so without adverse effects.

Aside from burst swim bladders, fish, like humans, can also get decompression sickness when exposed to rapid changes in pressure during capture.

“Bent” fish are most likely widespread in the live reef fish trade, as most of the species that have been examined were found to suffer symptoms of decompression sickness after capture from shallow depths of 10 to 15 metres.