Fish

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.

Common Lionfish

Proposed bill to ban lionfish sales in Florida

Tallahassee lawmakers are joining spear-wielding divers in an attempt to control Florida’s ever-increasing lionfish numbers. If passed, the two proposed bills would halt the public’s ability to purchase lionfish for aquariums and raising them for sale would become a level two felony.

“What the bill is going to do is prohibit the importation and sale of them,” said Sen. Greg Evers, R-Baker, who introduced the Senate version of the bill. “All of the details of the bill have not been decided. I’m saying let’s get rid of them. Put an end to lionfish in aquariums.”

All of the details of the bill have not been decided. I’m saying let’s get rid of them. Put an end to lionfish in aquariums.

—Sen. Greg Ever

Lionfish are an invasive species taking over coral reefs and preying on native fish in the Atlantic Ocean’s waters
Lionfish are an invasive species taking over coral reefs and preying on native fish in the Atlantic Ocean’s waters

Most lionfish too deep for divers to reach

Lionfish, which have spines that contain venom, are a well-known problem in Atlantic coral reefs. These invaders from the tropical parts of the Pacific and Indian oceans have no natural predators in the Atlantic Ocean. They are eradicating many fish populations in the shallow reefs that they have overtaken. Recently, the overwhelming problem has proven worse than originally thought.

European perch
European perch

Fish on psychiatric drugs behave odd

New research conducted by Swedish researchers finds that anxiolytic drugs in surface waters alter animal behaviours that are known to have ecological and evolutionary consequences

Researchers from Umeå University in Sweden examined how perch behaved when exposed to oxazepam, a drug commonly used to treat anxiety disorders in humans.

The scientists exposed the fish to concentrations of the drug similar to those found in the waters near densely populated areas in Sweden.

Lionfish are now found in waters from North Carolina south to Florida, the Caribbean, and all Gulf of Mexico states.
Lionfish are now found in waters from North Carolina south to Florida, the Caribbean, and all Gulf of Mexico states.

How to combat invasive lionfish

Lionfish have no natural predators and are taking food and habitat from native fish that are important to the local ecology and economy. Lionfish are now found in waters from North Carolina south to Florida, the Caribbean, and all Gulf of Mexico states.

This new manual, Invasive Lionfish: A Guide to Control and Management includes the best available science and practices for controlling lionfish in marine protected areas, national parks, and other conservation areas.

A painted comber hides in the seagrass

Fish get emotional too

Now, additional findings lends further credence to the notion that fish do indeed possess emotions and harbour thought processes. It turns out that fish growing up in the wild among predators use their left eye to look at novel objects, while their offspring raised in captivity use the right eye.



Male cichlid fish, Pelvicachromis taeniatus, prefer females with a larger pelvic fin, which indicates good body condition, proving that male mate choice may lead to changes in the scale of a female sexual trait.
Male cichlid fish, Pelvicachromis taeniatus, prefer females with a larger pelvic fin, which indicates good body condition, proving that male mate choice may lead to changes in the scale of a female sexual trait.

Female fish tango too

Pelvicachromis taeniatus is a dwarf cichlid from West Africa that is occasionally kept as an aquarium fish In this species, females seek to impress potential mates as well by fanning out their large, violet pelvic fin.



The results, published this month in BMC Evolutionary Biology, also suggest male choice can drive females to evolve exaggerated traits, a finding that disputes the traditional belief that sexual selection is a one-way road, allowing only females to affect male appearance.