Dept. of Conservation and Science, Urban Wildlife Institute, Lincoln Park Zoo, 2001 N Clark St, 60614 Chicago, IL, USA.
Dept. of Conservation and Science, Urban Wildlife Institute, Lincoln Park Zoo, 2001 N Clark St, 60614 Chicago, IL, USA.
Sci Total Environ. 2024 Nov 20;952:175883. doi: 10.1016/j.scitotenv.2024.175883. Epub 2024 Aug 31.
Anticoagulant rodenticides (ARs) are currently the most common method to control rats in cities, but these compounds also cause morbidity and mortality in non-target wildlife. Little attention has been focused on AR exposure among mesopredators despite their ecological role as scavengers and prey for larger carnivores, thus serving as an important bridge in the biomagnification of rodenticides in food webs. In this study, we sampled liver tissue from raccoons (Procyon lotor; n = 37), skunks (Mephitis mephitis; n = 15), and Virginia opossums (Didelphis virginiana; n = 45) euthanized by pest professionals and brown rats (Rattus norvegicus; n = 101) trapped in alleys in Chicago, USA to evaluate how often these species are exposed to ARs. We tested whether mesopredators had a higher prevalence of ARs and to more AR compounds compared to rats and calculated biomagnification factors (mean concentration in mesopredators/rats) as indicators of biomagnification. Of 93 sampled mesopredators, 100 % were exposed to at least one AR compound, mainly brodifacoum (≥80 %), and 79 % were exposed to multiple AR compounds. We also documented teal stomach contents consistent with the consumption of rat bait and altricial young tested positive to the same AR as their mother, suggesting mammary transfer. Of the 101 rats, 74 % tested positive to at least one AR compound and 32 % were exposed to multiple AR compounds. All mesopredator species had biomagnification factors exceeding 1.00 for brodifacoum (6.57-29.07) and bromadiolone (1.08-4.31). Our results suggest widespread exposure to ARs among urban mesopredators and biomagnification of ARs in mesopredators compared to rats. Policies that limit AR availability to non-target species, such as restricting the sale and use of ARs to licensed professionals in indoor settings, education on alternatives, and more emphasis on waste management may reduce health risks for urban wildlife and people in cities around the world.
抗凝血灭鼠剂 (ARs) 是目前控制城市鼠类最常用的方法，但这些化合物也会导致非靶标野生动物发病和死亡。尽管食腐动物在食物网中作为较大肉食动物的猎物和清道夫发挥着重要作用，但对于食腐动物接触 ARs 的情况却关注甚少。在本研究中，我们从美国芝加哥市被害虫防治专业人员安乐死的浣熊 (Procyon lotor; n = 37)、臭鼬 (Mephitis mephitis; n = 15) 和弗吉尼亚负鼠 (Didelphis virginiana; n = 45) 的肝脏组织以及在小巷中捕获的褐家鼠 (Rattus norvegicus; n = 101) 中采集样本，以评估这些物种接触 ARs 的频率。我们检测了食腐动物是否比大鼠更易接触 ARs 及更多的 AR 化合物，并计算了生物放大因子 (食腐动物/大鼠的平均浓度)，作为生物放大的指标。在所分析的 93 种食腐动物中，100%的个体接触到至少一种 AR 化合物，主要是溴敌隆(≥80%)，且 79%的个体接触到多种 AR 化合物。我们还记录了翠鸟胃内容物中含有鼠饵，且晚成性幼鸟的检测结果与母亲的 AR 相同，这表明 AR 通过乳腺转移。在 101 只大鼠中，74%的个体至少接触到一种 AR 化合物，32%的个体接触到多种 AR 化合物。所有食腐动物物种的溴敌隆 (6.57-29.07) 和溴鼠灵 (1.08-4.31) 的生物放大因子均超过 1.00。研究结果表明，城市食腐动物普遍接触 ARs，且 ARs 在食腐动物中的生物放大作用大于大鼠。限制 ARs 在非靶标物种中的使用，例如限制 ARs 在室内环境中向有资质的专业人员出售和使用、对替代品进行教育，以及更加重视废物管理，可能会降低城市野生动物和全球城市居民的健康风险。
