WASHINGTON — An all-female freshwater fish species called the Amazon molly that inhabits rivers and creeks along the Texas-Mexico border is living proof that sexual reproduction may be vastly ...

Several U.S. research teams report reproductive problems in Gulf Coast fish that periodically encounter oxygen at concentrations as low as those in so-called dead zones (SN: 6/5/04, p. 360: Dead ...

Low oxygen levels in coastal waters interfere with fish reproduction by disrupting the fishes' hormones, a marine scientist has found. Incidents of seasonal low levels of oxygen, known as hypoxia, ...

FRENCH RIVER, Minn. - The St. Louis River has a healthy population of adult lake sturgeon, but those fish are not producing the numbers of young fish that biologists had hoped to see. Few adult ...

Artificial reproduction in fish species encompasses a suite of techniques designed to overcome the limitations of natural spawning. By harnessing hormonal stimulation, controlled environmental ...

A DNA probing technique clarifies the mechanism behind clonal reproduction of female dojo loach fish, also providing insight into the ancestral origin of the clonal population. A DNA probing technique ...

Polar fish experience lower mortality than tropical fish, allowing them to delay reproduction until later in life when they are larger and can produce more eggs, according to a study by Mariana ...

A female stickleback fish, nick-named 'Mary', has produced offspring from eggs that appear to have been fertilized while they were still inside her, according to scientists at the University of ...

The law of unintended consequences gained new appreciation today when a five-year international study was published in the Journal of Animal Ecology detailing how long-term exposure to pharmaceutical ...

Seasonal hypoxia, when dissolved oxygen concentrations in water drop below 2 milligrams per liter, is a normal summer occurrence in estuaries. Over the past 20 years, however, pollution has increased ...