Bletz Molly C, Grant Evan H Campbell, DiRenzo Graziella
Department of Environmental Conservation, University of Massachusetts Amherst, Amherst, Massachusetts, USA.
U.S. Geological Survey Eastern Ecological Science Center (Patuxent Wildlife Research Center), Turners Falls, Massachusetts, USA.
Conserv Biol. 2025 Feb;39(1):e14363. doi: 10.1111/cobi.14363. Epub 2024 Aug 26.
Finding effective pathogen mitigation strategies is one of the biggest challenges humans face today. In the context of wildlife, emerging infectious diseases have repeatedly caused widespread host morbidity and population declines of numerous taxa. In areas yet unaffected by a pathogen, a proactive management approach has the potential to minimize or prevent host mortality. However, typically critical information on disease dynamics in a novel host system is lacking, empirical evidence on efficacy of management interventions is limited, and there is a lack of validated predictive models. As such, quantitative support for identifying effective management interventions is largely absent, and the opportunity for proactive management is often missed. We considered the potential invasion of the chytrid fungus, Batrachochytrium salamandrivorans (Bsal), whose expected emergence in North America poses a severe threat to hundreds of salamander species in this global salamander biodiversity hotspot. We developed and parameterized a dynamic multistate occupancy model to forecast host and pathogen occurrence, following expected emergence of the pathogen, and evaluated the response of salamander populations to different management scenarios. Our model forecasted that taking no action is expected to be catastrophic to salamander populations. Proactive action was predicted to maximize host occupancy outcomes relative to wait-and-see reactive management, thus providing quantitative support for proactive management opportunities. The eradication of Bsal was unlikely under all the evaluated management options. Contrary to our expectations, even early pathogen detection had little effect on Bsal or host occupancy outcomes. Our results provide quantitative support that proactive management is the optimal strategy for promoting persistence of disease-threatened salamander populations. Our approach fills a critical gap by defining a framework for evaluating management options prior to pathogen invasion and can thus serve as a template for addressing novel disease threats that jeopardize wildlife and human health.
寻找有效的病原体缓解策略是当今人类面临的最大挑战之一。在野生动物领域，新发传染病屡屡导致众多分类群的宿主广泛发病和种群数量下降。在尚未受到病原体影响的地区，积极主动的管理方法有可能将宿主死亡率降至最低或预防宿主死亡。然而，通常缺乏关于新宿主系统中疾病动态的关键信息，管理干预措施有效性的实证证据有限，并且缺乏经过验证的预测模型。因此，在很大程度上缺乏对确定有效管理干预措施的定量支持，积极主动管理的机会也常常错失。我们考虑了蛙壶菌（Batrachochytrium salamandrivorans，Bsal）的潜在入侵，其预计在北美出现对这个全球蝾螈生物多样性热点地区的数百种蝾螈物种构成严重威胁。我们开发并参数化了一个动态多状态占用模型，以预测病原体预期出现后宿主和病原体的发生情况，并评估蝾螈种群对不同管理方案的反应。我们的模型预测，不采取行动对蝾螈种群来说预计将是灾难性的。与观望式的被动管理相比，预计积极主动的行动能使宿主占用结果最大化，从而为积极主动管理的机会提供定量支持。在所有评估的管理选项下，根除Bsal都不太可能。与我们的预期相反，即使早期发现病原体对Bsal或宿主占用结果也几乎没有影响。我们的结果提供了定量支持，表明积极主动管理是促进受疾病威胁的蝾螈种群持续生存的最佳策略。我们的方法通过定义一个在病原体入侵前评估管理选项的框架填补了一个关键空白，因此可以作为应对危害野生动物和人类健康的新疾病威胁的模板。
