Patterns of widespread decline in North American bumble bees
Patterns of widespread decline in North American bumble bees
复制标题
DOI：
10.1073/pnas.1014743108
复制
发表时间：
2011-01-11
影响因子：
11.1
通讯作者：
Griswold, Terry L.
中科院分区：
文献类型：
--
作者：
Cameron, Sydney A.;Lozier, Jeffrey D.;Griswold, Terry L.
熊蜂（Bombus）是世界范围内野生植物和农作物的重要传粉者。然而，零散的观察表明，北美几个物种的数量下降。尽管美国国家科学院最近的一份报告强调了对这些观察结果的日益关注，但缺乏对大黄蜂减少的地理范围和可能的因果因素的国家评估。在这里，我们报告了一个3年的跨学科研究的结果，不断变化的分布，种群遗传结构，和病原体感染水平在美国各地的大黄蜂种群。我们比较了8个物种的当前和历史分布，编制了一个超过73，000个博物馆记录的数据库，用于与超过16，000个标本的全国性调查数据进行比较。我们发现，四个物种的相对丰度下降了高达96%，其调查的地理范围缩小了23- 87%，其中一些在过去的20年。我们还表明，下降的人口有显着较高的感染水平的微孢子虫病原体微孢子虫和较低的遗传多样性相比，共同发生的稳定（nondeclining）物种的人口。因此，较高的病原体流行率和减少的遗传多样性是北美这些令人担忧的下降模式的现实预测因素，尽管因果关系仍然不确定。
Bumble bees (Bombus) are vitally important pollinators of wild plants and agricultural crops worldwide. Fragmentary observations, however, have suggested population declines in several North American species. Despite rising concern over these observations in the United States, highlighted in a recent National Academy of Sciences report, a national assessment of the geographic scope and possible causal factors of bumble bee decline is lacking. Here, we report results of a 3-y interdisciplinary study of changing distributions, population genetic structure, and levels of pathogen infection in bumble bee populations across the United States. We compare current and historical distributions of eight species, compiling a database of >73,000 museum records for comparison with data from intensive nationwide surveys of >16,000 specimens. We show that the relative abundances of four species have declined by up to 96% and that their surveyed geographic ranges have contracted by 23-87%, some within the last 20 y. We also show that declining populations have significantly higher infection levels of the microsporidian pathogen Nosema bombi and lower genetic diversity compared with co-occurring populations of the stable (nondeclining) species. Higher pathogen prevalence and reduced genetic diversity are, thus, realistic predictors of these alarming patterns of decline in North America, although cause and effect remain uncertain.