Fish

The anemone fish's survival is at stake, due to climate change.

"Finding Nemo" clownfish won't survive climate change

A recent study by France’s National Centre for Scientific Research (CNRS), Woods Hole Oceanographic Institution (WHOI) and colleagues indicates that the anemonefish does not have the genetic ability to adapt swiftly enough to climate change.

The findings of the study were published in the November 27 issue of the Ecology Letters journal.

The research was conducted in the lagoons of Kimbe Bay, covering more than a decade. This area is a biodiversity hotspot in Papua New Guinea.

A cleaner wrasse interacts with its reflection in a mirror. A study, which suggests that fish might possess far higher cognitive powers than previously thought, has ignited an intense debate over how we assess the intelligence of animals

Do fish really possess higher cognitive powers?

Mirror self-recognition test

The standard method for testing whether an animal is self-aware is placing a mark on its body that cannot be viewed directly and then letting it have a look in a mirror. If the animal responds to its reflection and attempts to remove the mark it is considered evidence that the animal is self-aware.

Lake Trout (Salvelinus namaycush)
Lake Trout (Salvelinus namaycush)

Warmer waters in Ontario lakes messes with lake trout's diet

According to a new study, climate change is giving rise to changes in the diets of fishes in Ontario lakes, thereby altering the food webs there.

Researchers from the University of Guelph have discovered that the fish in Ontario lakes have been forced to forage in deeper waters due to the warmer average temperatures in the past decade. As a result, they consume prey species that are different from their normal diet, and this has led to a change in the flow of energy and nutrients in the lake.

A Matter of Sentience

Fish feel pain, or don’t they? Despite a growing body of sound evidence that fish do indeed feel pain and are sentient beings capable of all the types of cognition found in the “higher” mammals, with the possible sole exception of the ability to imitate, a group of critics seems to systematically seek to discredit this research. But for what reasons? Ila France Porcher takes a closer look at the stakes involved.

The Underrated Nurse Shark

Plentiful nurse sharks attended the sessions I held during my shark study in Tahiti. They are heavily-built animals with large, graceful fins, a long, pennant tail, and small eyes. They forage on the sea floor for a variety of foods at night and sleep in grottos in the coral during the days. Though these unusual sharks typically lie around on the sea floor, they are also capable of clambering.

The Killer Fish

Whereas the beaks of the common needlefish were needle-sized and shaped, this one's mouth was similarly pointed, but 15 cm long and lined with large, sharp, interlocking teeth. As I crumbled some bits of food for the ever present lagoon fish, it accelerated forward to take a morsel and the small fish shot away, creating a dazzling, submarine firework exploding in silence. When it opened its pointed mouth to take a morsel it revealed a throat nearly the same diameter as its body--it was well equipped to catch and swallow large prey.

Some fish 'farm' their food

Working on Palmyra atoll, around 1,000 miles south of Hawaii, a team of researchers from the University of California Santa Barbara became aware of the fish's farming habit when they noticed many bite marks in specific areas of algae growing on dead coral.

They followed these patches through time and found parrotfish were feeding heavily in each patch for a short period of time. Then, the fish would allow that exact location to recover before returning to harvest the algae again.