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In the research 4 compounds: Iodofenphos, Propetamphos, Dioxacarb and Permethrin and two commercial insecticides: Pibutoks Super (Permethrin) and Safrotin 10 WP (Propetamphos) were used to control anophelini females. The chemicals were tested in the laboratory on mosquitoes caught in the nature and the contact method was employed. Propctamphos and Permethrin at concentrations 0.05% and 0.1 %, after 2 hours of 1 hour exposure reduced the mosquitoes in 96% and 99.9% respectively. Iodofenphos and Dioxacarb, even at concentration 0.1 %, after 24 hours of 1 hour exposure caused barely 78.3% and 83.9% mortality of these insects. Both insecticides tested, in the 7 days period after the spraying, caused more than 97% reduction of the Anopheles population in the cow-sheds.
Hunting is among main pathways for intentional introductions of alien species. However, some of these species became pests and the main aim of their management is reducing population numbers. Raccoon dogs, raccoons and American minks were originally introduced outside the Polish territory and immigrated here around 1950s. Immigrants, supported by animals that escaped or were released from fur farms and hobby collections, established and spread to the level that makes their complete eradication unrealistic, despite since 2009 they can be hunted throughout the year and trapped. The only practicable management option for raccoon dog and American mink is long-term local control in areas of high natural value. The rate of invasion of raccoon can still be slowed down if more intensive control is applied. Efficiency of control of all three species in Poland is hindered by legal solutions which restrict hunting tolls to numbers approved at the beginning of the season. Justification of drastic control methods is questioned by different stakeholders, including some hunters, particularly if they are unlikely to have significant influence on the scale of invasion. Direct control of aliens species should therefore be accompanied by protection of native enemies and competitors, including protection of their habitats, and awareness-raising campaigns on reasons and consequences of biological invasions and means to reduce this problem.
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