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Mladica (Hucho hucho)
Marbled (Salmo marmoratus) A quick glance at a photo of a marble trout, Salmo trutta marmoratus, and you might think the hatchery folks were playing with the genetic tinkering machine again. Of course, if you hail from Slovenia, then you would know the marble trout is as native to the Adriatic (Mediterranean) region as brookies are to New England.
Today, genetically pure marble trout can be found only in the upper reaches of the Soca River Basin in northwestern Slovenia where national parks and a rural economy have kept the breathtaking landscape in pristine condition. The name "marble trout" originates from the olive-brown or olive-green and white pattern on its skin--it looks like a piece of hewn marble (and is reminiscent of a small lake trout). A marble trout is distinguished by a large head, which accounts for 22% to 25% of body length. Specimens over 30 inches and 20 pounds have been taken in the reservoirs along the Soca River, though fish of 1 to 1.5 pounds in the tributaries and 2-7 pounds in the main river are more the norm. Even before Hemingway fished the rivers of Slovenia during WWI, the beauty of the region attracted dedicated fly fishers from Italy, Austria and Germany. The ecoregion also includes a large number of introduced species that are believed to negatively impact native species. For example, hybridization of the rare marbled trout, Salmo marmoratus, with introduced brown trout, Salmo trutta, has reduced the genetic integrity of the native species. Endemic trout live in the rivers and lakes of this ecoregion, including Ohrid (Salmo letnica), Marbled (Salmo marmoratus), and Belushka (Acantholingua ohridana) trouts, as well as S. dentex. The ecoregion is home to a number of other endemic and rare fishes, many of which are vulnerable, endangered, or even critically endangered. More Pic Whirling Disease; What's It All About?
GOTEBORG, SWEDEN - Swedish scientists have found that female brown trout fake orgasms in about half of their spawnings.
Erik Peterrson of Sweden's National Board of Fisheries said out of 117 spawnings they observed, 69 were false orgasms. During a normal spawning, the female digs a gravel pit for the eggs. When she prepares to mate, she crouches down to protect the nest, opens her mouth and starts to quiver intensely. The male then swims alongside the female, assumes the same position,opens his mouth and starts to quiver as well. After a few seconds, the female releases her eggs and the male fertilizes them. But the researchers found that sometimes the female fakes it and doesn't release her eggs when the male releases his sperm. Peterrson said the sperm have to be directly over the eggs or the fertilization rate is very low. He thinks the female fakes it if the male isn't in exactly the right position. Confused males "If she feels he is not in the right position or timing, she just stops the
process," Peterrson said As It Happens. "But the male, he is so
excited that he misinterprets the female's cues and goes the whole way. He's a
little bit tricked there." He added the male looks a little confused because
when the female fakes orgasm, she doesn't cover the eggs as she would during a
normal spawning. Instead, she may dig some more to prepare the gravel pit for
the next mating in about 30 minutes. And it seems trout aren't alone.
Researchers first saw this in Atlantic salmon in 1954. They now think it's
common in all salmon.
We saw brown trout that looked to be upward of seven or eight pounds, as well as a fish Johannes identified as the softmouth trout (Salmothymus obtusirostris). Softmouth trout live in only one other stream - the Buna River, in Bosnia, which we also visited. They are characterized by a slight overbite, presumably to facilitate feeding on insects on the river bottom. They had black spots, like brown trout, and silver and gold sides "There is no fish more difficult to catch,
nor that gives the true angler more genuine sport than the trout. His
capture requires the nicest tackle, the greatest skill, the most complete
sell-command, the highest qualities of mind and body. The arm must be
strong that wields the rod; the eye true that sees the rise; the wrist
quick that strikes at the instant; the judgement good, that selects the
best spot, the most suitable fly, and knows just how to kill a fish. A
line temper is required to bear up against the loss of a noble fish, and
patient perseverance to conquer ill luck." A flowing fresh water stream is all business. It rushes forward. If it slows at all, it is just to create small whirlpools or eddies, and then it's back on down the mountain. It makes its bed on gravel or hard rock. Its water is cool, sometimes painfully cold, especially in the spring when the stream is brimming with newly-melted snow. A stream is not like a river. A stream's banks follow the straight and narrow. No playful meandering curves, no muddy bottom, no sunny, quiet shores. A river is a stream without the push. Animals that live in a stream are adapted to life in the fast lane. Brook trout have strong, streamlined bodies and powerful tail fins that can push against the current. These fish need the cold, oxygen-rich water of a flowing stream in order to thrive. Shade is very important in keeping the stream cold. When forest fires, lumbering, or road building make streams lose their shade, they also lose their trout. Atlantic salmon are famous for their ability to buck the current. They swim upstream in spring in order to lay their eggs on the gravel bottom where they were born. Where man-made dams block their route, they will dash themselves to death against the concrete walls trying to leap over them. On some rivers fish ladders help anadromous fish continue their journey. These are fish, such as salmon, shad, and herring, which spend part of their lives in the ocean, but return to fresh water to reproduce. Other animals adapt to the swift current. Black fly larvae attach their rear ends to the underside of rocks by tiny hooks. If they lose their foothold (so to speak), they can lasso another rock with silken threads. Caddis fly larvae fashion durable homes from sand grains, leaf pieces, or grasses.
HEAVEN: is where the Police are British HELL: is where the Cooks are British
No fish were killed in the making of this web page This page was last updated on 04/21/07.
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