Sands Bryony, Mgidiswa Neludo, Nyamukondiwa Casper, Wall Richard
School of Biological Sciences University of Bristol Bristol UK.
Department of Biological Sciences and Biotechnology Botswana International University of Science and Technology Palapye Botswana.
Ecol Evol. 2018 Feb 14;8(5):2938-2946. doi: 10.1002/ece3.3896. eCollection 2018 Mar.
Pyrethroid insecticides are widely used to control ectoparasites of livestock, particularly ticks and biting flies. Their use in African livestock systems is increasing, driven by the need to increase productivity and local food security. However, insecticide residues present in the dung after treatment are toxic to dung-inhabiting insects. In a semiarid agricultural habitat in Botswana, dung beetle adult mortality, brood ball production, and larval survival were compared between untreated cattle dung and cattle dung spiked with deltamethrin, to give concentrations of 0.01, 0.1, 0.5, or 1 ppm. Cattle dung-baited pitfall traps were used to measure repellent effects of deltamethrin in dung on Scarabaeidae. Dung decomposition rate was also examined. There was significantly increased mortality of adult dung beetles colonizing pats that contained deltamethrin compared to insecticide-free pats. Brood ball production was significantly reduced at concentrations of 1 ppm; larval survival was significantly reduced in dung containing 0.1 ppm deltamethrin and above. There was no difference in the number of Scarabaeidae attracted to dung containing any of the deltamethrin concentrations. Dung decomposition was significantly reduced even at the lowest concentration (0.01 ppm) compared to insecticide-free dung. The widespread use of deltamethrin in African agricultural ecosystems is a significant cause for concern; sustained use is likely to damage dung beetle populations and their provision of environmentally and economically important ecosystem services. Contaminated dung buried by paracoprid (tunneling) beetles may retain insecticidal effects, with impacts on developing larvae below ground. Lethal and sublethal effects on entire dung beetle (Scarabaeidae) communities could impair ecosystem function in agricultural landscapes.
拟除虫菊酯类杀虫剂被广泛用于控制家畜的体外寄生虫，尤其是蜱虫和吸血蝇。由于提高生产力和当地粮食安全的需求，它们在非洲家畜养殖系统中的使用正在增加。然而，处理后粪便中存在的杀虫剂残留对栖息在粪便中的昆虫有毒。在博茨瓦纳的一个半干旱农业栖息地，比较了未处理牛粪和添加了溴氰菊酯的牛粪（浓度分别为0.01、0.1、0.5或1 ppm）对蜣螂成虫死亡率、育幼球产量和幼虫存活率的影响。使用牛粪诱饵陷阱来测量溴氰菊酯在粪便中对金龟科昆虫的驱避效果。还研究了粪便分解率。与不含杀虫剂的牛粪堆相比，定殖在含有溴氰菊酯的牛粪堆上的成年蜣螂死亡率显著增加。在1 ppm浓度下，育幼球产量显著降低；在含有0.1 ppm及以上溴氰菊酯的粪便中，幼虫存活率显著降低。吸引到含有任何溴氰菊酯浓度粪便上的金龟科昆虫数量没有差异。与不含杀虫剂的粪便相比，即使在最低浓度（0.01 ppm）下，粪便分解也显著减少。溴氰菊酯在非洲农业生态系统中的广泛使用是一个重大问题；持续使用可能会损害蜣螂种群及其提供的对环境和经济都很重要的生态系统服务。被副蜣螂（挖掘型）甲虫掩埋的受污染粪便可能会保留杀虫效果，从而影响地下发育的幼虫。对整个蜣螂（金龟科）群落的致死和亚致死影响可能会损害农业景观中的生态系统功能。
