Lake Sturgeon Assessment on the St. Marys River
PI: Ashley Moerke, PhD and Roger Greil
Historically, lake sturgeon (Acipenser fulvescens) were an abundant species throughout the Great Lakes Basin. However, commercial over-harvest, habitat degradation, and barriers to spawning habitat have resulted in lake sturgeon populations declining to 1% of their original abundance (Harkness and Dymond 1961). Since lake sturgeon grow slowly and take many years to reach sexual maturity, natural recovery of depleted populations may be a long and difficult process. Recently, fisheries biologists have taken interest in this primitive fish in an effort to restore its once abundant population. Stakeholders are making strides towards restoration goals through habitat protection, water quality improvement, and education but, lake sturgeon still remain listed as a federally threatened species throughout most of their native range. Additionally, their abundance throughout the Great Lakes, including the St. Marys River, still remains relatively unknown (Holey et al. 2000). Understanding the current status of lake sturgeon in the St. Marys River is essential to advocate further management initiatives. The objective of this research is to assess the current lake sturgeon population in the St. Marys River, an ecologically unique ecosystem, in efforts to strengthen future conservation and management strategies.
Lake sturgeon assessments have been conducted by ARL researchers since 2000 and are still ongoing. Setlines are set for 12 to 24 h intervals at multiple water depths and baited with a variety of baits during late summer. All sturgeon captured are measured for length, girth, and weight. Fin samples are taken for DNA and age analyses. Before release, all sturgeon are tagged for future identification.
Click here to view annual reports on the sturgeon assessments.