Scholarlink

<p>Imbalanced fish communities, often driven by the dominance of invasive or overabundant native species, can destabilize aquatic ecosystems, limit management options, and reduce the resilience of desirable fish species. To explore whether reducing a biotic stressor could move a walleye <i>Sander vitreus</i> population into a resilient safe operating space (SOS), we conducted&#xa0;a whole-lake physical removal of overabundant black bullhead <i>Ameiurus melas</i> on Howell Lake, Wisconsin, during 2020–2024. We removed an estimated 779,208 bullhead (46.8&#xa0;kg/ha), reducing the adult population by 97%. Although bullhead relative abundance (catch-per-unit-effort [CPUE]) significantly declined, walleye natural recruitment failed to meet our safe operating space criteria as hypothesized. Black crappie <i>Pomoxis nigromaculatus</i> CPUE significantly increased following bullhead removal, and age-0 walleye CPUE declined, revealing a threshold-like negative correlation consistent with previous studies. Our results suggest that the system may have transitioned to a new state dominated by black crappie, which are suppressing walleye recruitment despite extensive bullhead removal. Our findings illustrate that managing for resilience through species dominance shifts may yield unpredictable outcomes, highlighting the importance of anticipating compensatory responses of nontarget species and addressing multiple stressors when attempting to restore imperiled fish populations to an SOS.</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

Exploring a safe operating space for walleye by rebalancing an aquatic community

  • 期刊论文

  • 发表日期：

    2026年3月23日

查看全文
  • Logan W. Sikora,
  • Joseph T. Mrnak,
  • Gregory Matzke,
  • Stephanie L. Shaw,
  • Justin A. VanDeHey,
  • Greg G. Sass

摘要

Imbalanced fish communities, often driven by the dominance of invasive or overabundant native species, can destabilize aquatic ecosystems, limit management options, and reduce the resilience of desirable fish species. To explore whether reducing a biotic stressor could move a walleye Sander vitreus population into a resilient safe operating space (SOS), we conducted a whole-lake physical removal of overabundant black bullhead Ameiurus melas on Howell Lake, Wisconsin, during 2020–2024. We removed an estimated 779,208 bullhead (46.8 kg/ha), reducing the adult population by 97%. Although bullhead relative abundance (catch-per-unit-effort [CPUE]) significantly declined, walleye natural recruitment failed to meet our safe operating space criteria as hypothesized. Black crappie Pomoxis nigromaculatus CPUE significantly increased following bullhead removal, and age-0 walleye CPUE declined, revealing a threshold-like negative correlation consistent with previous studies. Our results suggest that the system may have transitioned to a new state dominated by black crappie, which are suppressing walleye recruitment despite extensive bullhead removal. Our findings illustrate that managing for resilience through species dominance shifts may yield unpredictable outcomes, highlighting the importance of anticipating compensatory responses of nontarget species and addressing multiple stressors when attempting to restore imperiled fish populations to an SOS.