A night seining technique for sampling juvenile Atlantic salmon in streams

G. Gries; B. H. Letcher

doi:10.1577/1548-8675(2002)022%3c0595:anstfs%3e2.0.co;2

Home/Archive/USGS

USGS · 1015018

A night seining technique for sampling juvenile Atlantic salmon in streams

G. Gries·B. H. Letcher

View original source ↗Export metadata ↓

Abstract

For many studies of the population dynamics, growth, and movement of juvenile Atlantic salmon Salmo salar , it is necessary to resample tagged individuals multiple times. However, common sampling techniques such as electrofishing can have negative effects on fish survival and growth, especially when individuals are repeatedly sampled. We describe an alternative to electrofishing that involves sampling at night with small, one-person seines. Juvenile Atlantic salmon in a small brook were tagged with passive integrated transponder tags and sampled 15 times by means of night seining, day electrofishing, and day seining techniques. Capturing juvenile Atlantic salmon by day seining was inefficient, resulting in a capture probability estimate of 0.18. The mean capture probability estimate was 0.45 during night seining samples and 0.78 during electrofishing samples. The total number of age-0 Atlantic salmon captured via night seining increased 4.5 times after fish attained a mean fork length of just over 60 mm. A much greater number of brook trout Salvelinus fontinalis and brown trout Salmo trutta were captured in electrofishing samples than in night seining samples. Night seining may prove useful when electrofishing is impractical, when threatened or endangered species exist, or when multiple recaptures of individuals are desired.

Explore related subjects

North American Journal of Fisheries Management Article

Source-reported bounding extent: 42.41217770289301° to 42.456394245096185° latitude; -72.71249771118164° to -72.61636734008789° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

G. Gries, B. H. Letcher. 2002. A night seining technique for sampling juvenile Atlantic salmon in streams. https://doi.org/10.1577/1548-8675(2002)022%253c0595%3Aanstfs%253e2.0.co%3B2

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related USGS reports

USGS2026

Water and endangered fish in the Klamath River basin revisited: Does old age or Upper Klamath Lake surface elevation and water quality affect adult Lost River Sucker and Shortnose Sucker survival? A response to Kann and Walker

Our update responds to recent scientific critiques and again finds no evidence that lake levels or water conditions influence adult sucker survival. This reaffirms our prior work (Krause et al., 2022) and suggests that recent declines in adult survival may reflect an aging population.

Oregon↗

USGS2026

Environmental relationships with Silver Carp population ecology across the Mississippi River basin

Objective Silver Carp Hypophthalmichthys molitrix are of special concern to fisheries management agencies across the Mississippi River basin, but effective control of the species is challenging. Our objectives were to (1) identify spatial and environmental patterns among key Silver Carp demographic rates that could be exploited by removal programs and (2) develop predictive models of Silver Carp demographic rates using readily available environmental data that could potentially be used to quantify population ecology without expending the resources to conduct population assessments. Methods We collected Silver Carp from six rivers within the lower Mississippi River subbasin (i.e., Arkansas, Cache, Mississippi, St. Francis, White, and Yazoo rivers) and compiled raw data from populations in the upper Mississippi, Missouri, and Ohio River subbasins to estimate demographic rates (i.e., growth, mortality, and recruitment variability). We compared the demographic rates among subbasins and between main stems and tributaries using standard nonparametric tests. We used information-theoretic model selection to evaluate relationships among demographic rates, environmental conditions, and invasion stage. Results In general, lower Mississippi River subbasin populations exhibited faster growth and lower mortality than did those from the upper Mississippi River subbasin. Populations in main-stem rivers did not differ from those in tributaries. More established populations in warmer, free-flowing rivers (e.g., White River) generally experienced faster growth, lower mortality, and more stable recruitment than less established populations in cooler, impounded rivers (e.g., Illinois River). Conclusions The results indicated that variability in Silver Carp populations was related to environmental conditions and invasion stage. Our results suggested that the effectiveness of removal programs might be improved by targeting populations in warm hydrologically variable rivers, as they may have increased reproduction capacities and emigration rates. The equations provided here may be used to estimate population demographics for Silver Carp and help determine their potential sensitivity to management actions, without expending the resources that are required to collect population-specific biological data.

Mississippi River basin↗

USGS2026

Arctic Grayling, scared to death: Are Brown Trout an impediment to Arctic Grayling reintroduction success in Michigan?

Introduction: Arctic Grayling Thymallus arcticus were extirpated from Michigan in 1936. Their demise was caused by over-fishing, habitat destruction from large-scale logging, and Brook Trout Salvelinus fontinalis and Brown Trout Salmo trutta. Subsequently, Brook and Brown trout have become the dominant salmonid species in Michigan streams. Past attempts to restore Grayling to Michigan have been unsuccessful perhaps due to competition with these now resident salmonids. Objective: To determine the impacts of competition between age-0 Arctic Grayling and age-0 Brook and Brown Trout on Grayling growth and survival. Methods: Competition trials were performed in experimental streams, lasting two months, across three years, with three treatment types: the control, 10 Grayling with 10 Grayling; the Brook Trout treatment, 10 Grayling with 10 Brook Trout; and the Brown Trout treatment, 10 Grayling with 10 Brown Trout. Results: Brown Trout had a significant effect on Arctic Grayling growth and mortality, while Brook Trout had no effect on Arctic Grayling growth or mortality. Conclusion: Age-0 Brown Trout negatively impacted growth, condition, and survival of age-0 Arctic Grayling, while the impacts of age-0 Brook Trout or conspecifics were negligible. This suggests reintroduction of Arctic Grayling may be more successful in streams with few or no Brown Trout.

Michigan↗