10/20/2023 0 Comments Fishing planet sturgeon unique timesHowever, a growing share of males in polluted waters are hermaphrodites (bottom), inappropriately bearing scores of eggs and testes (yellow) containing mature sperm. At spawning time, the belly of a normal female shovelnose sturgeon (top) is full of black eggs. Crownover, Seaweb/Caviar Emptor GENDER SURPRISE. Their eggs were fertilized by hand and the resulting fry raised in a hatchery until old enough (right) for restocking. Ural River beluga and other sturgeon (left) were netted on a spawning run in Kazakhstan upstream of the Caspian Sea, and later released. Balla/Mote Magazine ASSISTED REPRODUCTION. New trade restrictions on caviar are intended to protect the species. Scientists there and elsewhere around the world are rearing sturgeon species and restocking wild populations. This week-old Siberian sturgeon, shown with its reflection, was born at a research center in Florida. In several rivers, biologists such as these give Mother Nature an assist. The late-April scene occurs as, throughout the northern Midwest, water temperatures climb above 56☏ (13☌) and lake sturgeon swim upstream to spawn. As the team restrains her, one member massages her swollen belly, working her eggs out of a release vent and into a plastic pail. The moves wouldn’t be out of place in a rodeo. On a fine spring day alongside a Wisconsin river, several biologists wrestle a muscular, 120-pound fish onto her back and straddle her.
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