Towards integrated adaptive management of an endangered elasmobranch in the North East Atlantic

对东北大西洋濒危软骨鱼类进行综合适应性管理

• 批准号: 2287138
• 金额: --
• 依托单位: University of Aberdeen
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2287138
• 关键词: Towards; integrated; adaptive; management; endangered

Increasing use is made of marine protected areas (MPAs) to locally manage and conserve marine biodiversity. Although highly mobile, with complex temporal and spatial movement patterns, many endangered elasmobranchs show site association to critical habitats at important life history stages. Consequently MPAs are considered a key management tool in shark conservation. Low fecundity, long gestation periods and historical exploitation have precipitated severe declines in spurdog (Squalus acanthias) biomass in the North East Atlantic (NEA). As aggregating species spurdog are identified as both endangered in the NEA (IUCN) and paradoxically as choke species, fouling fishing gear. NEA populations are considered a single stock from tagging data, with wide-ranging regional movements characteristic. Yet recent work suggests some individuals display winter residency within the 'Loch Sunart to Sound of Jura' MPA (Thorburn et al. 2015), originally designated to protect critically endangered flapper skates. Determining the status (source or sink) of current spurdog population(s) in this MPA, and connectivity via contemporary gene flow with other NEA populations, is paramount for viable population management. Identification and integration of residential behaviour may increase management effectiveness by identifying critical areas where MPAs could conserve migratory species.Our previous genetic analyses revealed little population structure within the NEA, and identified relatives within aggregations (Thorburn et al. 2018), indicating unsuspected vulnerability through erosion of selectable familial variation, making estimates of effective population size, aggregation composition and provenance key questions in managing for viability. Indirect population genetic approaches function well where there is restricted gene flow and prior knowledge of population boundaries, yet these assumptions are difficult to justify for the highly mobile spurdog. Additionally, demographic interpretation of traditional analyses remains challenging, which integrate processes on evolutionary rather than contemporary timescales. However, information contained in the spatial distribution of close kin can provide direct estimates of population connectivity and have been successfully used for defining dispersal kernels, identifying the drivers of juvenile dispersal patterns, and investigating contemporary recruitment dynamics.Approach: Juvenile and adult contemporary management relevant connectivity will be inferred from spatial distribution of parent-offspring, full- and half-siblings, identified from genome-wide SNP analysis, from the MPA and adjacent sites, and contrasted with indirect estimates of connectivity obtained from maternally inherited mitogenomes (Feutry et al. 2017). Additionally data on close kin pairs (parents and offspring) will be utilised in a close-kin mark-recapture (CKMR) approach to estimate absolute stock abundance. Provenance of individuals will be confirmed by lead isotope analysis utilising isotopic seascape approaches that we have developed and used for a variety of conservation issues.This QUADRAT (DTP) project will provide training in core and generic skills, along with cutting edge technologies (population genomics, bioinformatics, stable isotopes and multi-elemental fingerprinting) integrating Biodiversity and Earth systems; translating into improved policy and practice for effective conservation management of endangered marine species. Key questions: Does the existing MPA encompass recruitment areas? What temporal site associations exist? Is philopatry (return to natal sites) evident? Do adult abundance and productivity estimates suggest viable Scottish populations? What management measures are likely to sustain connectivity and viability?

人们越来越多地利用海洋保护区 (MPA) 来本地管理和保护海洋生物多样性。尽管具有高度流动性，具有复杂的时间和空间运动模式，但许多濒临灭绝的软骨鱼在重要的生命史阶段表现出与关键栖息地的关联。因此，海洋保护区被认为是鲨鱼保护的关键管理工具。繁殖力低、妊娠期长和历史性开发导致东北大西洋（NEA）的角鲨（Squalus acanthias）生物量严重下降。作为聚集性物种，马刺犬在国家环境局 (IUCN) 中被认定为濒危物种，但矛盾的是，它又被认为是窒息物种，会污染渔具。从标记数据来看，NEA 种群被视为单一种群，具有广泛的区域流动特征。然而最近的研究表明，一些个体在“苏纳特湖到汝拉之声”海洋保护区（Thorburn et al. 2015）中展示了冬季居住地，该保护区最初是为了保护极度濒危的摩登溜冰鞋而设计的。确定该 MPA 中当前杂种犬种群的状态（源或汇），以及通过当代基因流与其他 NEA 种群的连接，对于可行的种群管理至关重要。对居住行为的识别和整合可以通过确定海洋保护区可以保护迁徙物种的关键区域来提高管理效率。我们之前的遗传分析几乎没有揭示NEA内的种群结构，并确定了聚集内的亲属（Thorburn等人，2018），这表明由于可选择的家族变异的侵蚀而导致意想不到的脆弱性，从而对有效种群规模、聚集组成和来源进行估计是生存能力管理中的关键问题。间接群体遗传方法在基因流动受限和群体边界先验知识的情况下可以很好地发挥作用，但这些假设很难证明高度流动性的马刺狗是合理的。此外，传统分析的人口统计解释仍然具有挑战性，它整合了进化过程而不是当代时间尺度的过程。然而，近亲空间分布中包含的信息可以提供对种群连通性的直接估计，并已成功用于定义扩散核心、确定青少年扩散模式的驱动因素以及调查当代招募动态。方法：青少年和成人当代管理相关的连通性将从亲子、全兄弟姐妹和同父异母兄弟姐妹的空间分布中推断出来，这些空间分布是从全基因组 SNP 中确定的。 来自 MPA 和邻近站点的分析，并与从母系遗传的线粒体基因组获得的连接性间接估计进行对比（Feutry 等人，2017）。此外，近亲对（父母和后代）的数据将用于近亲标记重捕获（CKMR）方法来估计绝对种群丰度。个体的来源将通过使用我们开发并用于各种保护问题的同位素海景方法进行铅同位素分析来确认。该 QUADRAT (DTP) 项目将提供核心和通用技能的培训，以及整合生物多样性和地球系统的尖端技术（群体基因组学、生物信息学、稳定同位素和多元素指纹识别）；转化为有效保护管理濒危海洋物种的改进政策和实践。关键问题：现有的 MPA 是否涵盖招聘领域？存在哪些时间位点关联？ philopatry（返回出生地）是否明显？成人丰度和生产力估计是否表明苏格兰有可生存的人口？哪些管理措施可能维持连通性和生存能力？