Seems to me AK47 that the risks here are very real, especially considering our native species do not reproduce at the same rate and may not be prolific enough to eat that many carp...so your European comparison is foolish, especially when you read about how cane toads have transformed a large swath of Australia since their introduction for comparison.
http://www.reabic.net/journals/bir/2...Elgin_etal.pdf
"The impacts of C. gibelio on native fish
communities and aquatic ecosystems in Southern
Alberta have not been estimated. However, the
negative impacts described in Europe, Asia, and
the Middle East suggest impacts in Alberta could
be substantial. The establishment of C. gibelio in
Europe has caused multiple fishery declines,
particularly with native cyprinids (Economidis et
al. 2000; Gaygusuz et al. 2007). C. gibelio have
a gynogenetic reproductive strategy that results
in reproductive competition that may reduce
native cyprinid population size (Tarkan et al.
2012). In Alberta, the May – August spawning
period of many native cyprinids overlaps with C.
gibelio’s, and increase the likelihood of reproductive
competition and subsequent population decline
(Nelson and Paetz 1992; Kottlat and Freyhof
2007). Direct competition for pelagic zooplankton
and benthic invertebrates may also reduce native
cyprinid populations (Lusk 2010). Additionally,
by removing pelagic zooplankton, C. gibelio can
weaken the top-down control zooplankton excerpt
on phytoplankton, resulting in turbid water.
Furthermore, consumption of lake benthos stirs
up bottom sediments, which can contribute to
increased turbidity. The irrigation canals, small
prairie streams, and shallow lakes also typically
lack piscivorous fish, leading to a lack of predation
on C. gibelio.
First detected in a single lake in 2006, C.
gibelio has since been documented as occurring
in parts of three adjacent major drainage basins
in the Canadian province of Alberta. Because
sampling effort has been uneven, additional
sampling may reveal an even broader distribution
and greater abundance. The potential consequence
of this uncontrolled spread is especially high
since the Oldman and South Saskatchewan River
basins border the Milk River, which is part of the
Mississippi River basin. A recent risk assessment
and climate match model conducted by the U.S.
Fish and Wildlife Service concluded that C.
gibelio has a moderate to high climate match with the U.S.A. states that border Alberta and
that the United States is at high risk of invasion
(U.S. Fish and Wildlife Service 2012). This suggests
that southern Canadian provinces with similar
climates are equally vulnerable to invasion. In
the absence of management efforts to control
their populations and spread, C. gibelio is likely
to continue spreading into new basins, causing
unknown consequences to native biota, ecosystems,
and economies."
Linear Mode
