Quote:
Originally Posted by Long Shot
The US Fish and Wildlife Service Summary for Crucian Carp was posted a couple posts up. The species here is Prussian Carp and this is the link to the FWS summary for that species. It includes many references to impact studies in Europe where it has had major impacts on native species and habitats.
http://www.fws.gov/injuriouswildlife..._8-14-2012.pdf |
Long Shot that is a great read it just reinforces what many of us have been afraid of.... That is if you want to believe biologists and long term studies over "facts based on observation and communication with local fishermen that hang out there"
Quote:
Originally Posted by jeprli
Silvers are filter feeders and much larger, Prussian carp is omnivorous and does not grow as large, they don't dig up bottom sediment like common carp.Biggest danger is competition for spawning structure with other non predatory species.
Depleting lakes of oxygen? That's science fiction, not a fact.
This is like comparing tiny lemon sharks to a great white.
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Quote from the study
“The Prussian carp is a prolific fish species [that] is believed to be responsible for the decline of native fish, invertebrate and plant populations in different areas. Furthermore,
it is notorious for increasing water turbidity because of its habit of stirring up bottom sediments during feeding. C. gibelio has the potential to hybridi[z]e with other Carassius species and Cyprinus carpio.”
Quote:
Originally Posted by jeprli
Prussian carp has never displaced or stunted any predator species. If it were so, all of southern/central Alberta reservoirs would be full of them. These carp did not show up yesterday, some of the earliest catches are from 95/96 caught NE of Strathmore in farm dugouts and irrigation ponds.
These ponds are fine examples that Prussian carp is not as dangerous to Alberta waters as everybody wants to think. It is populated by perch, Prussian carp, lake whitefish, tulibee, suckers and pike (some very large pike for given size of waterbody). All these fish have different age classes within species. Yes perch and carp seem to be in biggest number, after them would be tulibee and then whitefish and last pike.
Lower number of pike is due to greedy fisherman keeping every one they can catch, same goes for whitefish.
So my point is after 20 years of their known existence in a fairly small body of water(about 6 meters deep and size of a football field) they have not been able to overtake the ecosystem, nor did perch. I've never witnessed a winterkill at this location so oxygen levels must be fine.
These are facts based on observation and communication with local fisherman that hang out there. Something that very few of you if any can claim. That is why I don't believe in Internet studies and bs videos. First hand experience tells me a different story.
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Quote from the study
“Established in natural waters. Migrated from the Danube to the confluence of the Dyje and Morava rivers after 1975. Has
competed heavily for food and space with C. carassius populations, Tinca tinca, Leucaspius deliniatus, and other native cyprinids
thereby decreasing their populations".
"Presently the most dominant fish species in lentic and slowly running aquatic habitats.”
“Amongst the most invasive species of introduced freshwater fish is the gibel (or Prussian) carp"
“The expansion of gibel carp populations in Estonia and the surrounding Baltic Sea is worthy of concern"
"Reproduces efficiently, and
competes with native fishes for food and space. In some parts of central Europe, it has affected the range of other indigenous and commercially more
valuable fish species.”