Researchers in Sweden have discovered that traces of many medicines can be found in fish that have been swimming in treated waste water. One such medicine, the hormone levonorgestrel, was found in ...

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, ...

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 ...

(Beyond Pesticides, June 1, 2010) Atrazine, one of the most commonly used herbicides in the world, has been shown to affect reproduction of fish at concentrations below U.S. Environmental Protection ...

From the coastline to freshwater streams, people living in Amazonia say industrial fishing, deforestation, hydroelectric dams and climate change have reduced fish populations. Industrial fishing is ...

A consistent metabolic ratio found across 133 Chinese marine and freshwater fish species provides new evidence in support of the idea that fish become sexually active—and spawn for the first time—in ...

A new peer-reviewed research paper, authored by Shedd Aquarium and published in Journal of Great Lakes Research, assesses the fish species that spawn in the Chicago River to sustain and support ...

In this segment of “North Dakota Outdoors,” host Mike Anderson takes us to Lake Sakakawea during this year’s fall fish reproduction survey. Fisheries supervisor Russ Kinzler says this year’s fall fish ...

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 ...