Fishes, which are commonly considered to be cold, unsocial, and unintelligent, are capable of negotiating reciprocal cooperative systems, Australian researchers find.
In pairs of coral reef rabbitfishes (f. Siganidae), one fish frequently assumes an upright vigilance position in the water column, while the partner forages in small crevices in the reef substratum. Both behaviours are strongly coordinated and partners regularly alternate their positions, resulting in a balanced distribution of foraging activity.
In this study, researchers discovered that fish larvae around the world used external cues like the sun, Earth’s magnetic field and sounds to find their way around in the open ocean.
The fish larvae were able to control their destination and migrate by keeping a bearing.
The wide and flat-faced, striped critter known as the splendid toadfish is just that—splendid! Underwater photographer and author Steve Rosenberg takes a closer look at what makes this lovable fish so special.
I had my initial encounter with a splendid toadfish on my very first trip to Cozumel in 1978. I remember my dive guide excitedly motioning me over, gesturing enthusiastically toward the edge of a small sandy area, where it abutted against the bottom edge of the reef. I swam over to take a look, getting low as he directed. I kept scanning the general area where he was pointing, but saw nothing of particular interest. I finally realized what he had spotted, when I was no more than a foot away from a very strange little fish.
At the time of the spring tide (new moon and full moon), thousands of puffer fish around the world head for the coastlines to spawn. There, they gather at the water’s edge and vigorously tremble their bodies to spawn.
Scientists have long wondered how the puffer fish were able to synchronise their spawning with the lunar cycle.
A paper published in a recent issue of the Current Biology journal has the answers.
Aside from sharks, moray eels are one of the most maligned and misunderstood of all marine animals. Thought by many to be highly dangerous because of their depiction in films and books, morays are not malicious monsters, but important predators of any healthy marine ecosystem. They are generally shy and docile if not harassed. Nigel Marsh shares insights about these animals.
I met my first moray as a thirteen-year-old and it was an encounter I will never forget. At the time, in the 1970s, the moray was considered to be a very dangerous animal, reported to attack divers and fishers. I had read stories of Roman slaves being fed to hungry morays for entertainment and had recently seen the film The Deep, which included a scene where an enormous moray attacks and kills a diver. So, when I encountered a 2m-long giant moray while snorkelling on the Great Barrier Reef, I was understandably terrified!
Scientists have observed instances in which tuna rub themselves against the side of sharks. Apparently, they do this to dislodge painful parasites that cling to their head, eyes and gills.
“Shark skin is really smooth in one direction and it’s like sandpaper in the other,” said Chris Thompson, a Research Fellow at the University of Western Australia.
Thompson and his colleagues observed this behaviour after studying the footage of floating, baited underwater cameras which they had deployed in 36 regions in the Pacific, Indian and Atlantic Oceans in 2012 to 2019.
The 3.19 million barrels of crude oil that spilled into the Gulf of Mexico during the Deepwater Horizon in 2010 had a devastating impact to the natural environment, as well as the people and animals in the vicinity.
A study on the mahi-mahi in the nearby waters revisits the incident by studying how fish in the wild are being affected from the exposure to crude oil.
For more than a decade, some researchers in Australia have been monitoring coral reefs in the vicinity to see how rising ocean temperatures affect both the tropical and temperate reef fish communities.
The findings of their study was published in the Current Biology journal.
According to lead author Rick Stuart-Smith, a marine ecologist at the University of Tasmania, the team had focused on reef fishes as reefs provided many benefits to people and the fishes there helped maintain the natural ecological function of the reefs.
A study in the Proceedings of the Royal Society B Biological Sciences journal has found out that the ideal time for neon goby embryos to hatch is within two hours of sunrise.
For coral reef embryos, this knowledge is important as the time of their hatching is a perilous time that directly affects their survival. Yet many of them have to decide on their own when to hatch, according to corresponding author John Majoris, a research scientist at The University of Texas at Austin.
Like other fish, minnows can adjust their body temperatures to match that of their surroundings.
Research into the effects of climate change on fish generally focus on their heat tolerance at an increase of two or three degrees Celsius above the current average temperatures.
However, a recent University of Illinois study wanted to find out how fathead minnows handled short-term temperature spikes—those amounting to as much as 5 to 10 degrees Celsius above average.