Scholarlink

<p>In response to northern pike (<i>Esox lucius</i>) population declines, wetland habitat modifications were created in drowned river-mouth tributaries and coastal bays to enhance reproduction in a functional restoration effort. Modified habitats (spawning pools and channels) were excavated within dense monodominant invasive cattail (<i>Typha</i> x <i>glauca</i>) to increase habitat diversity and connectivity to improve degraded habitat and access to remaining upslope wet-meadow for spawning northern pike. Over a five-year period (2017–2021) of fish sampling, similar densities of young-of-the-year (YOY) northern pike were captured emigrating from the modified habitats and unmodified reference habitats that had retained habitat function (e.g. connectivity) indicating rapid use of created habitat. Water-level dynamics (i.e., spring water-levels and change in water-levels) operated interactively, to improve connectivity, fish access, and ultimately produce YOY northern pike. High spring water-levels followed by historically strong flood pulses were positively associated with densities of YOY northern pike emigrating from both modified and unmodified habitats, despite near-anoxic conditions that developed during high water-levels. In contrast, when low spring water-levels were not followed by a strong flood pulse, relatively lower densities of YOY northern pike were captured, despite warm and normoxic waters. Results demonstrate dynamic and interactive relationships among hydrological and abiotic conditions and YOY northern pike reproduction outcomes that should be considered in water-level regulation policies and habitat enhancement strategies.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Water-Level Variability Mediates Northern Pike Reproduction at Restored Coastal Habitats in the Upper St. Lawrence River, USA

  • 期刊论文

  • 发表日期：

    2025年3月14日

查看全文
  • John Paul Leblanc,
  • John M. Farrell

摘要

In response to northern pike (Esox lucius) population declines, wetland habitat modifications were created in drowned river-mouth tributaries and coastal bays to enhance reproduction in a functional restoration effort. Modified habitats (spawning pools and channels) were excavated within dense monodominant invasive cattail (Typha x glauca) to increase habitat diversity and connectivity to improve degraded habitat and access to remaining upslope wet-meadow for spawning northern pike. Over a five-year period (2017–2021) of fish sampling, similar densities of young-of-the-year (YOY) northern pike were captured emigrating from the modified habitats and unmodified reference habitats that had retained habitat function (e.g. connectivity) indicating rapid use of created habitat. Water-level dynamics (i.e., spring water-levels and change in water-levels) operated interactively, to improve connectivity, fish access, and ultimately produce YOY northern pike. High spring water-levels followed by historically strong flood pulses were positively associated with densities of YOY northern pike emigrating from both modified and unmodified habitats, despite near-anoxic conditions that developed during high water-levels. In contrast, when low spring water-levels were not followed by a strong flood pulse, relatively lower densities of YOY northern pike were captured, despite warm and normoxic waters. Results demonstrate dynamic and interactive relationships among hydrological and abiotic conditions and YOY northern pike reproduction outcomes that should be considered in water-level regulation policies and habitat enhancement strategies.