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Spatiotemporal use of a tributary by lake sturgeon over a 10-year period

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Lauren McDonald
Lauren McDonald
Lauren McDonald
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Tim Haxton at Ontario Ministry of Natural Resources and Forestry
Tim Haxton
  • Ontario Ministry of Natural Resources and Forestry
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Abstract and Figures

A telemetry study was conducted on lake sturgeon to determine the seasonal use and environmental factors that stimulate movement within a tributary of a larger system. Over a 10-year period, 52 lake sturgeon implanted with acoustic transmitters were monitored through an array of Vemco receivers with the Blanche River, Ontario. An average of 68% of the tagged fish entered the tributary annually whereas only 19.2% of those were detected on known spawning areas approximately 54 km upstream. Water temperature, lunar phase, lake water level, presumed spawning fish, and water discharge were all considered significant variables associated with the onset of upstream migration. Water temperature (mean 12.9 °C) was the only variable that explained the timing and the arrival at the spawning grounds. Sturgeon remained at the spawning area for a mean duration 7.9 days; however, none of the variables examined explained the duration of stay. Water temperature was the only variable that explained departure from the spawning areas (mean 15.8 °C). Mean time spent in the river after spawning was 30.5 days. There was not a significant difference in sex or total length in relationship to the duration tagged fish stayed in the river after spawning. The entire Blanche River up to the insuperable rapids was used by the sturgeon with the exception of minor tributaries. Water temperature, river discharge, and fish size were all considered significant factors initiating out-migration back into the lake. This study demonstrated the importance and seasonal use of a tributary by lake sturgeon. Correlations from abiotic variable and seasonal response could be used to establish guidelines for water management purposes when the goal is to conserve or restore sturgeon populations within a river system. This study also illustrates the importance of tributaries in association to a larger waterbody for lake sturgeon.
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Vol.: (0123456789)
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Environ Biol Fish (2023) 106:853–874
https://doi.org/10.1007/s10641-022-01384-9
Spatiotemporal use ofatributary bylake sturgeon
overa10‑year period
LaurenMcDonald· TimHaxton
Received: 14 March 2022 / Accepted: 21 December 2022 / Published online: 28 December 2022
© Crown 2022
Abstract A telemetry study was conducted on lake
sturgeon to determine the seasonal use and environ-
mental factors that stimulate movement within a
tributary of a larger system. Over a 10-year period,
52 lake sturgeon implanted with acoustic transmitters
were monitored through an array of Vemco receiv-
ers with the Blanche River, Ontario. An average of
68% of the tagged fish entered the tributary annually
whereas only 19.2% of those were detected on known
spawning areas approximately 54km upstream. Water
temperature, lunar phase, lake water level, presumed
spawning fish, and water discharge were all consid-
ered significant variables associated with the onset
of upstream migration. Water temperature (mean
12.9°C) was the only variable that explained the tim-
ing and the arrival at the spawning grounds. Sturgeon
remained at the spawning area for a mean duration
7.9 days; however, none of the variables examined
explained the duration of stay. Water temperature
was the only variable that explained departure from
the spawning areas (mean 15.8°C). Mean time spent
in the river after spawning was 30.5days. There was
not a significant difference in sex or total length in
relationship to the duration tagged fish stayed in the
river after spawning. The entire Blanche River up to
the insuperable rapids was used by the sturgeon with
the exception of minor tributaries. Water temperature,
river discharge, and fish size were all considered sig-
nificant factors initiating out-migration back into the
lake. This study demonstrated the importance and
seasonal use of a tributary by lake sturgeon. Corre-
lations from abiotic variable and seasonal response
could be used to establish guidelines for water man-
agement purposes when the goal is to conserve or
restore sturgeon populations within a river system.
This study also illustrates the importance of tribu-
taries in association to a larger waterbody for lake
sturgeon.
Keywords Lake sturgeon· Interannual movement·
Long-term study· Tributary use
Introduction
Tributaries are important features moving water from
the landscape through lakes and larger rivers to the
ocean. These rivers were fundamental for the explora-
tion of new lands in North America and as a primary
means to transport goods back to European markets.
The levels of alteration to rivers increased with colo-
nial settlement and increasing populations. Rivers
became the main corridors for the transporting of
timber to mills and markets (Kelso etal. 1996). Later,
L.McDonald
KirklandLake, Canada
T.Haxton(*)
Aquatic Research andMonitoring Section, Ontario
Ministry ofNatural Resources andForestry, 2140 East
Bank Drive, Peterborough, ONK9J7B8, Canada
e-mail: tim.haxton@ontario.ca
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... Other studies have similarly found that some individual lake sturgeon will remain in overwintering areas, while others show seasonal movement patterns in and out of overwintering areas in spring and fall, e.g. in the Winnipeg River, Mani-toba, Canada (Barth et al. 2011). Our findings are also similar to a recent long-term study which demonstrated that lake sturgeon used the entire Blanche River, Ontario, (about 54 km) and used different river sections only during the spring and summer season (McDonald & Haxton 2023). 4.3.2. ...
... Blanche River, Ontario; McDonald & Haxton 2023), and hydroelectrically dammed rivers (e.g. Mississippi River, USA; Knights et al. 2002) can have drastically different flow regimes and temperature profiles compared to the intact, relatively shorter North French River, and river discharge can affect seasonal lake sturgeon movements (Borkholder et al. 2002, McDonald & Haxton 2023. Including considerations of the differences in methodologies and flow regimes when comparing results among studies is important for drawing contextualized conclusions and for comparing fish movement and behaviour between impacted and intact river systems. ...
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... Telemetry is an important tool that can provide insight into sturgeon behavior (Wildhaber et al. 2011;Nelson et al. 2013), environmental stimuli for initiating movement (Goodman et al. 2013;Vine et al. 2019;Ecclestone et al. 2020;McDonald and Haxton 2023), and extent of movement (Fredrich et al. 2008;Wishingrad et al. 2014); help identify potential spawning areas (Wildhaber et al. 2011;Taylor and Litvak 2017) and significant habitat areas for the species (Hale et al. 2016;Novak et al. 2017); or ascertain population dynamics such as survival from long-term studies (Colborne et al. 2021;McDonald and Haxton 2023). Telemetry can both help assess reproductive population sizes (Kazyak et al. 2020) and can facilitate the identification of areas for which further, more targeted studies can be directed (e.g., Wildhaber et al. 2011;Taylor and Litvak 2017). ...
... Telemetry is an important tool that can provide insight into sturgeon behavior (Wildhaber et al. 2011;Nelson et al. 2013), environmental stimuli for initiating movement (Goodman et al. 2013;Vine et al. 2019;Ecclestone et al. 2020;McDonald and Haxton 2023), and extent of movement (Fredrich et al. 2008;Wishingrad et al. 2014); help identify potential spawning areas (Wildhaber et al. 2011;Taylor and Litvak 2017) and significant habitat areas for the species (Hale et al. 2016;Novak et al. 2017); or ascertain population dynamics such as survival from long-term studies (Colborne et al. 2021;McDonald and Haxton 2023). Telemetry can both help assess reproductive population sizes (Kazyak et al. 2020) and can facilitate the identification of areas for which further, more targeted studies can be directed (e.g., Wildhaber et al. 2011;Taylor and Litvak 2017). ...
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Post‐release dispersal and spawning movements of a translocated lake sturgeon (Acipenser fulvescens, Rafinesque 1817) population in the Mattagami River, Ontario
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Species translocations are increasingly being used as a management tool to mitigate population losses due to such factors as habitat degradation and fragmentation, but post‐introduction follow‐up is relatively sparse. Post‐translocation telemetry can assess success by identifying activity, emigrations, survival, habitat usage, and reproductive events, aiding in the continued management of translocated populations and informing future efforts. This study assessed movement of translocated adult lake sturgeon (Acipenser fulvescens) immediately post‐release and a decade later, and tested for associations between environmental variables and spawning movements. Prior to their translocation in 2002, 13 of 51 adult lake sturgeon were surgically implanted with radio telemetry tags and tracked for 1 year. In 2011 and 2013, eight additional adults were captured within the reintroduction site and implanted with radio‐tags. Six of the 13 sturgeon tagged in 2002 dispersed downstream over a dam during the early post‐release period. In spring 2014, tagged adults were tracked to the spillway at the release area's inflow, and spawning was confirmed by larval captures. Movement data for tagged adults differed between the two tracking periods, showing marked differences in behaviour over time. Water velocity was correlated with upstream and downstream spawning movements, with water temperature also correlated with downstream movement. Research regarding post‐translocation movement and dispersal provides insight on behavioural responses following translocation, and may improve outcomes by informing future efforts.
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Seasonal movements of shortnose sturgeon (Acipenser brevirostrum) in the Altamaha River, Georgia
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Shortnose sturgeon (Acipenser brevirostrum) populations were decimated by a variety of anthropogenic activities throughout much of the 20th century. Understanding the spatial and temporal dynamics of spawning migrations within natal rivers is a critical information gap with regard to habitat protection and ultimately, species recovery. The objectives of this study were to document and describe seasonal movements of shortnose sturgeon in the Altamaha River system, Georgia. Passive acoustic telemetry was used to monitor the movements of 40 adult individuals from April 2011 through February 2014. Telemetry data revealed that during much of the year, the adults resided within the tidally influenced portion of the river, with most detections occurring near the freshwater–saltwater interface. Upstream movements to potential spawning habitat occurred during winter and early spring, and most fish returned to the lower estuary by April. Upstream migrations appeared to be triggered by environmental cues and were initiated when mean weekly temperatures in the lower Altamaha River were 11.6–16.9 °C. Unlike spawning migrations documented in northern rivers, the pattern of movement observed in this study was a single‐step migration without an apparent resting or staging period. Upstream migrations during nonspawning months were also observed and appeared to correspond with increasing discharge, which potentially resulted in increased channel navigability and habitat availability in nondrought years. This study further illustrates the clinal variations in life history typical of the species and may have important implications on river‐specific strategies for species recovery.
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