Movement patterns and habitat characteristics of Lake Sturgeon (Acipenser fulvescens) in the St. Marys River, Michigan, 2007–2008

Effects of acoustic tag implantation on lake sturgeon Acipenser fulvescens: lack of evidence for changes in behavior

“…Difficulty with the determination of sex in the field limited our ability to detect whether being male or female affected behavior after tag implantation, and thus, may have introduced some bias into our analyses. The seriousness of this potential bias is difficult to assess given that sex-based differences in lake sturgeon activity, movements, and migration timing have been observed in some systems [28,29] but not in others [30,31]. Reproductive status also should be considered as an explanatory variable in future tagging effects studies on lake sturgeon given that activity may be greatest during the post-spawn phase [29,30,32].…”

“…The seriousness of this potential bias is difficult to assess given that sex-based differences in lake sturgeon activity, movements, and migration timing have been observed in some systems [28,29] but not in others [30,31]. Reproductive status also should be considered as an explanatory variable in future tagging effects studies on lake sturgeon given that activity may be greatest during the post-spawn phase [29,30,32]. Few (≤25 %) lake sturgeon in our study were spawning-ready, so results may be more representative of individuals in between spawning cycles than actively spawning fish.…”

A global perspective of fragmentation on a declining taxon—the sturgeon (Acipenseriformes)

“…Impacts of habitat fragmentation resulting from dam construction are widespread and well documented , McDermid et al 2011, Haxton et al 2014. Barriers can present significant obstacles to the continued presence of sturgeon in historically occupied waters given that sturgeon often utilize entire river systems (Welsh & McLeod 2010, Gerig et al 2011) to find the habitat necessary to fulfill the requirements of particular stages of the life cycle (Smith & King 2005). While safe, unimpeded movement up and downstream at barriers could possibly ameliorate the situation, passage efficiency in the limited instances where it is known to occur has been minimal (Cooke et al 2002, Parsley et al 2007, Thiem et al 2011 and at a high energetic cost to the fish (Thiem et al 2016).…”

Population status and demographics of lake sturgeon (Acipenser fulvescens) in the St. Marys River, from 2000 to 2007

“…Eight years of lake sturgeon assessments, along with movement studies (see Gerig et al, 2011), suggest that the St. Marys River contains a localized population of lake sturgeon within the North Channel of Sugar Island and Lake George. Lake sturgeon were captured throughout the sampled area downstream of the Soo Locks and upstream of Neebish Island, with a majority of successful captures in the North Channel and Lake George.…”

“…Before release, captured lake sturgeon were inspected for any observable abnormalities including lamprey scars and external parasites. In 2006 and 2007, 18 adult lake sturgeon were implanted with sonic transponders with a 4-year battery life (Gerig et al, 2011).…”