The Ontario Eastern Bluebird Society, Cambridge, Ontario, Canada.
Environment and Climate Change Canada, Delta, British Columbia, Canada.
Environ Toxicol Chem. 2021 Dec;40(12):3369-3378. doi: 10.1002/etc.5218. Epub 2021 Oct 29.
We analyzed the reproductive success of eastern bluebirds (Sialia sialis) nesting in apple orchards and non-orchard nest-boxes in southern Ontario, Canada, from 1988 to 2018. Using data from 2397 nest-boxes monitored at 20 orchard sites and 52 non-orchard sites, we first modeled phenological parameters typically linked to climate change across both site types. We found that the first egg of each brood was laid significantly earlier in the season each year over our 31-year study. Clutch initiation occurred 4 days earlier in the spring in 2018 compared to 1988. Average clutch size in the first or second brood did not change significantly during our 31-year study; however, clutches were significantly smaller in orchards compared to non-orchards (0.10 ± 0.03 fewer eggs between sites). Nests built in orchards were also at 6.1-fold greater risk of parasitism and 2.1-fold greater risk of depredation than nests in non-orchards. After accounting for depredation and nest parasitism, hatching success was still significantly lower in orchards than in non-orchards. Overall, hatching success was 4%-5% lower in orchards. The probability of successfully fledging did not differ significantly between site types. In 2012, a ban on use of the organophosphate insecticide azinphos-methyl in orchards was enacted in Canada. We did not find a difference in hatching or fledging success in orchards after the ban. In our assessment of available data, we conclude that any pesticide effect on hatching success of eastern bluebirds in sprayed orchards is most likely the consequence of long-term exposure to dichlorodiphenyltrichloroethane (DDT) compounds in orchard soils and bioaccumulation in eggs rather than pesticides in use since regulation of DDT in the 1970s. Environ Toxicol Chem 2021;40:3369-3378. © 2021 Her Majesty the Queen in Right of Canada. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Environment and Climate Change Canada.
我们分析了 1988 年至 2018 年间在加拿大安大略省南部的苹果园中以及非果园巢箱中筑巢的东方蓝鸟（Sialia sialis）的繁殖成功率。利用 20 个果园和 52 个非果园监测点的 2397 个巢箱的数据，我们首先在两种类型的地点上建立了与气候变化相关的典型物候参数模型。我们发现，在我们的 31 年研究中，每年的第一个育雏季节的第一只蛋都更早地产卵。与 1988 年相比，2018 年春季的产蛋期提前了 4 天。在我们的 31 年研究中，第一窝或第二窝的平均卵数没有明显变化；然而，与非果园相比，果园中的卵数明显减少（窝间相差 0.10±0.03 个卵）。果园中筑巢的巢也有 6.1 倍的寄生虫感染风险和 2.1 倍的捕食风险。在考虑了捕食和巢寄生的情况下，孵化成功率仍然明显低于非果园。总的来说，果园的孵化成功率比非果园低 4%-5%。成功育雏的概率在两种类型的地点之间没有显著差异。2012 年，加拿大颁布了禁止在果园使用有机磷杀虫剂毒死蜱的禁令。我们没有发现禁令实施后果园孵化或育雏成功率的差异。在对现有数据的评估中，我们得出的结论是，杀虫剂对喷洒果园中东方蓝鸟孵化成功率的任何影响，最有可能是果园土壤中滴滴涕（DDT）化合物的长期暴露和卵中的生物累积，而不是自 20 世纪 70 年代以来使用的农药造成的。环境毒理化学 2021；40:3369-3378。©2021 加拿大女王陛下以其自身名义出版。环境毒理化学由 Wiley 期刊出版公司代表 SETAC 出版。经加拿大环境与气候变化部长许可转载。
