Dark muscle in fish, often reddish-brown or gray, is a normal anatomical feature rich in fat and oxygen-binding proteins.

Rachael has a degree in Zoology from the University of Southampton, and specializes in animal behavior, evolution, palaeontology, and the environment. Rachael has a degree in Zoology from the ...

Scientists using new ways to eavesdrop on fish have captured a cacophony of thumps, honks, burps and grunts in underwater recordings.

A nearly-extinct fish has been spotted in Missouri's river basins. This fish's comeback is significant to scientists, and you ...

The state is on a campaign to remove invasive smallmouth bass, which harm ecosystems and eat other fish, threatening native species. Colorado Parks and Wildlife runs a fishing tournament every other ...

Unusual preservative in specimen jars proved to be a sweet solution for studying changes in genetic diversity among fish ...

The escape of 75,000 farmed fish from damaged pens in the Highlands could pose a genetic threat to native Atlantic salmon.

This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated. (NEXSTAR) — It is not common for the oarfish ...