RAPID: The effects of wildfire on salmonid olfaction and behavior

RAPID：野火对鲑鱼嗅觉和行为的影响

• 批准号: 2136943
• 负责人: Eric Palkovacs
• 金额: $ 20万
• 依托单位: University of California-Santa Cruz
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2136943&HistoricalAwards=false
• 关键词: RAPID; effects; wildfire; salmonid; olfaction

Olfaction, the sense of smell, is critical for aquatic animals to sense their surroundings. Toxic compounds in the environment may interfere with this ability. Wildfire has become a dominant feature of Western landscapes. When forests burn, they can release toxic heavy metals, which ultimately end up in streams. These compounds may interfere with the ability of animals to smell their surroundings, thereby changing behavior. This research examines the effects of recent California wildfires on the olfaction and behavior of Pacific salmon. Salmon use their sense of smell to detect predators. If this ability is disrupted, they may quickly become a predator’s lunch. Salmon also use smell to find their way back to their home streams to reproduce after years at sea. This process, called olfactory imprinting, is a specialized form of learning that juvenile salmon experience in streams. If this imprinting is disrupted, they are unable to find their way back to their home stream as adults. This research uses behavioral experiments to test whether fish from fire-impacted streams are less able to smell predators. It uses behavioral experiments and cellular studies of olfactory function to test whether fish from fire-impacted streams are less able to recognize and imprint on their home watersheds. This project will train students, broaden participation in science, advance a general understanding of the effects of sensory pollutants on wild populations, and contribute critical information to inform salmon management in a drier, more fire-prone landscape.In aquatic environments, olfactory cues provide important information that animals use to make behavioral decisions. Wildfires may cause large-scale disturbance to aquatic chemical environments that may impact olfaction and behavior at the scale of entire ecosystems. Fires release organic and inorganic compounds into streams. Some of these compounds, including heavy metals, may disrupt olfaction and alter behavior. This proposed research combines behavioral experiments with gene expression assays to ask: How does wildfire impact juvenile salmonid olfaction and behavior in natural streams? Recent wildfires that occurred in August 2020 along the Central California Coast have generated a mosaic of burned and unburned watersheds. This project uses a paired sampling design, pairing burned and unburned streams within four watersheds. Spatially isolated sites within each watershed have been selected to ensure juvenile salmonids cannot move between the burned and unburned sites. This project will measure the concentrations of heavy metals in stream water and in fish muscle tissue from burned and unburned streams within each watershed. The behavior of juvenile salmonids from burned and unburned streams will be compared in terms of predator avoidance and recognition of natal stream water. The expression of genes associated with normal olfactory function and natal homing will be compared between fish from burned versus unburned streams. If the release of heavy metals by fire disrupts juvenile salmonid olfaction, then fish from burned streams are expected to exhibit weaker predator avoidance, impaired recognition of natal stream water, and reduced expression of genes associated with olfactory imprinting.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.

嗅觉，嗅觉，是水生动物感知周围环境的关键。环境中的有毒化合物可能会干扰这种能力。野火已成为西方景观的主要特征。当森林燃烧时，它们会释放出有毒的重金属，最终流入溪流。这些化合物可能会干扰动物闻到周围环境的能力，从而改变行为。这项研究调查了最近加州野火对太平洋鲑鱼嗅觉和行为的影响。鲑鱼用嗅觉来发现捕食者。如果这种能力被破坏，它们可能很快就会成为捕食者的午餐。鲑鱼也利用气味找到回到家乡溪流的路，在海上生活多年后繁殖。这个过程被称为嗅觉印记，是幼鲑鱼在溪流中经历的一种特殊的学习形式。如果这种印记被破坏，它们就无法在成年后找到回到家乡的路。这项研究使用行为实验来测试来自受火灾影响的河流的鱼类是否不太能够闻到捕食者。它使用行为实验和嗅觉功能的细胞研究来测试来自受火灾影响的河流的鱼类是否不太能够识别和印记它们的家流域。该项目将培训学生，扩大科学参与，促进对感官污染物对野生种群影响的普遍理解，并提供关键信息，为在干燥，更容易发生火灾的景观中管理鲑鱼提供信息。在水生环境中，嗅觉线索提供动物用于做出行为决策的重要信息。野火可能会对水生化学环境造成大规模的干扰，这可能会影响整个生态系统的嗅觉和行为。火灾将有机和无机化合物释放到溪流中。其中一些化合物，包括重金属，可能会破坏嗅觉并改变行为。这项拟议中的研究将行为实验与基因表达测定相结合，以探讨：野火如何影响天然溪流中幼鲑的嗅觉和行为？最近于二零二零年八月沿着中加州海岸发生的野火，已产生一个已燃烧和未燃烧的流域马赛克。该项目采用配对抽样设计，在四个流域内配对燃烧和未燃烧的溪流。每个流域内的空间隔离的网站已被选定，以确保青少年鲑鱼不能移动之间的燃烧和未燃烧的网站。该项目将测量每个流域内燃烧和未燃烧的溪流中的溪流水和鱼肌肉组织中的重金属浓度。少年鲑鱼燃烧和未燃烧的流的行为将比较捕食者回避和识别纳塔尔流水。与正常的嗅觉功能和纳塔尔相关的基因的表达将比较鱼从燃烧与未燃烧流。如果释放的重金属火扰乱少年鲑鱼嗅觉，然后鱼从燃烧流预计将表现出较弱的捕食者回避，削弱识别纳塔尔流水，并减少与嗅觉imprinting.This奖项相关的基因表达反映NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。