RAPID: Recolonization dynamics following mass mortality in the ecologically important sunflower star (Pycnopodia helianthoides)

RAPID：生态上重要的向日葵星（Pycnopodia helianthoides）大规模死亡后的再殖民动态

• 批准号: 2224698
• 负责人: Michael Dawson
• 金额: $ 15.87万
• 依托单位: University of California - Merced
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-06-01 至 2025-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2224698&HistoricalAwards=false
• 关键词: RAPID; Recolonization; dynamics; following; mass

Many marine species are known for their large population sizes and high dispersal potential due to the time their larval offspring spend in the open ocean before settling into the adult habitat. Despite these characteristics, that often buffer against decimation, the sunflower sea star (Pycnopodia helianthoides) suffered major declines between 2013 and 2020 due to a disease outbreak and warming events, which led to listing by the IUCN as Critically Endangered. The sunflower star helps maintain ecological balance in kelp forest ecosystems; its absence across large swaths of its range has led to concerns for the future of the ecosystem. This loss has highlighted the need to better understand dispersal and recovery dynamics in this ecologically important species in a time when global change stressors are intensifying. The widespread loss of Pycnopodia — combined with recent sightings of new juveniles in the range where it’s been lost — created an opportunity to answer questions about the genetic relatedness among new colonists, source populations of colonists, patterns of gene expression, and associations with environmental factors, and their implications for the future of the species. The investigators are collaborating with a diverse team of partners already surveying the coast, to collect genetic information from new colonists. The research proposed here has direct and consequential impacts on conservation actions for Pycnopodia through ongoing collaborations with the Nature Conservancy and fills an important gap for future conservation decisions aimed at restoring this important member of the kelp forest ecosystem to its historical range. As more species come under threat from rapidly intensifying global change, understanding recovery dynamics is an important and necessary step in instigating conservation actions. The investigator is developing a teaching lesson for a nearby community college and an undergraduate student will be trained.Massive demographic declines associated with anthropogenically-induced stressors have increased in recent years, raising questions about species’ ability to recover. The ecologically important sunflower sea star (Pycnopodia helianthoides) has suffered a precipitous (88–100%) decline since 2013 due to sea star wasting (SSW) disease and warming. The widespread loss of Pycnopodia provides a backdrop against which recent sightings of new juveniles in the extirpated range offer an opportunity to examine the contributions of four processes — (1) sweepstakes reproductive success, (2) cohesive dispersal, (3) larval cloning, and (4) allele surfing — to the evolutionary trajectory of populations following mass mortality. Additionally, identifying propagules’ source populations, evaluating gene expression profiles, and analyzing genotype–environment associations of colonists can help elucidate potential colonization pathways that favor recovery or signal ongoing threats. The investigators are soliciting new opportunistic collections of Pycnopodia from many partners and are responding to any observation in California and Oregon to acquire the samples and generate the whole genome resequencing data needed to test hypotheses segregating the aforementioned processes. As more species come under threat from rapidly intensifying global change, understanding recovery dynamics is critical to understanding population dynamics in the marine benthic environment.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

许多海洋物种以其庞大的种群规模和高扩散潜力而闻名，这是因为它们的幼虫后代在进入成年栖息地之前在开阔的海洋中度过了一段时间。尽管有这些特征，但由于疾病爆发和变暖事件，向日葵海星星（Pycnopodia helianthoides）在2013年至2020年期间遭受了重大衰退，导致IUCN将其列为极度濒危物种。向日葵星星有助于维持海带森林生态系统的生态平衡;它在大片范围内的缺失导致了对生态系统未来的担忧。这一损失突出表明，在全球变化压力加剧的时候，需要更好地了解这一生态重要物种的扩散和恢复动态。Pycnopodia的广泛损失-再加上最近在它已经失去的范围内看到新的青少年-创造了一个机会来回答新殖民者之间的遗传相关性，殖民者的来源群体，基因表达模式，与环境因素的关联，以及它们对物种未来的影响。研究人员正在与已经在海岸进行调查的不同合作伙伴团队合作，从新殖民者那里收集遗传信息。通过与大自然保护协会的持续合作，这里提出的研究对Pycnopodia的保护行动产生了直接和间接的影响，并填补了未来保护决策的重要空白，旨在将海带森林生态系统的这一重要成员恢复到其历史范围。随着越来越多的物种受到快速加剧的全球变化的威胁，了解恢复动态是促进保护行动的重要和必要步骤。 研究人员正在为附近的一所社区大学开发一门教学课程，一名本科生将接受培训。近年来，与生殖应激源相关的大规模人口下降有所增加，这引发了人们对物种恢复能力的质疑。自2013年以来，由于海洋星星萎缩（SSW）疾病和变暖，生态上重要的向日葵海星星（Pycnopodia helianthoides）遭受了急剧（88-100%）的下降。密足目的广泛消失提供了一个背景，最近在灭绝范围内看到新的幼鱼提供了一个机会来研究四个过程的贡献-（1）抽奖式繁殖成功，（2）凝聚扩散，（3）幼虫克隆，（4）等位基因冲浪-在大规模死亡后种群的进化轨迹。此外，确定繁殖体的来源种群，评估基因表达谱，并分析殖民者的基因型-环境关联可以帮助阐明有利于恢复或信号持续威胁的潜在殖民途径。研究人员正在从许多合作伙伴那里征集新的机会性密足类标本，并对加州和俄勒冈州的任何观察作出反应，以获取样本并生成测试分离上述过程的假设所需的全基因组重测序数据。随着越来越多的物种受到快速加剧的全球变化的威胁，了解恢复动态对于了解海洋底栖环境中的种群动态至关重要。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。