Benefits of stocking fewer but larger individuals with implications for native fish recovery

Fonken, Dale; Conner, Mary M.; Walsworth, Timothy E.; Thompson, Paul D.

doi:10.1139/cjfas-2022-0071

Cited by 6 publications

(1 citation statement)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For RGS Minnow, the demographic boost is only moderate, even in years when the CPUE of wild fish is very low, because the survival of hatchery fish is likely very low: 9–25% (Yackulic et al 2022). Increasing the production of RGS Minnow may not be feasible given hatchery constraints; however, increasing postrelease survival through other means, such as flow training or release of larger fish, may be possible (Franssen et al 2021; Fonken et al 2022). Evaluation of actions intended to increase postrelease survival may be difficult, as recapture rates of small fish in medium to large rivers are often very low even when large numbers of hatchery fish are used for these studies (Archdeacon and Remshardt 2012; Platania et al 2020).…”

Section: Discussionmentioning

confidence: 99%

Hatchery supplementation increases potential spawning stock of Rio Grande Silvery Minnow after population bottlenecks

Archdeacon

Dudley²,

Remshardt

et al. 2023

Trans Am Fish Soc

View full text Add to dashboard Cite

Objective: Supplementation of imperiled wild fish stocks with captively raised fish is a commonly used conservation tool. Programs designed to maintain or improve fish populations through supplementation should be evaluated to determine whether they are meeting conservation objectives. The Rio Grande Silvery Minnow Hybognathus amarus is a small-bodied, endangered minnow endemic to the Rio Grande basin of the southwestern United States. The wild population of Rio Grande Silvery Minnow has been supplemented with captive-reared fish since 2002. Our objective was to determine whether supplementation measurably increases the number of spawning fish after years of population bottlenecks; this objective was simplified because nearly all hatchery-released fish have been given identifying markings. Methods:We leveraged a long-term fish sampling data set (18 years) covering the species' contemporary range and a single-season, high spatial coverage fish sampling data set to determine whether the number of potential spawners was increased by the addition of hatchery fish.Result: Hatchery-reared fish increased the catch rates of spawners by up to an order of magnitude in some years. We also observed that most hatchery-reared fish were recaptured near the point of release. We were able to determine that supplementation with hatchery fish increased the abundance and distribution of Rio Grande Silvery Minnow and provided the desired demographic boost after severe population bottlenecks. Conclusion:Releasing hatchery-reared fish may be a useful tool for conservation of imperiled freshwater fishes. However, there is a need for spawning and rearing infrastructure that matches the life-history of the species and sufficient postrelease monitoring to evaluate the effectiveness of hatchery supplementation. Use of hatchery-reared fish has been beneficial for improving population resiliency of Rio Grande Silvery Minnow following recruitment bottlenecks; however, natural

show abstract

Section: Discussionmentioning

confidence: 99%

Hatchery supplementation increases potential spawning stock of Rio Grande Silvery Minnow after population bottlenecks

Archdeacon

Dudley²,

Remshardt

et al. 2023

Trans Am Fish Soc

View full text Add to dashboard Cite

show abstract

Whole-lake acoustic telemetry to evaluate survival of stocked juvenile fish

Koeberle,

Pearsall,

Hammers

et al. 2023

Sci Rep

View full text Add to dashboard Cite

Estimates of juvenile survival are critical for informing population dynamics and the ecology of fish, yet these demographic parameters are difficult to measure. Here, we demonstrate that advances in animal tracking technology provide opportunities to evaluate survival of juvenile tagged fish. We implemented a whole-lake telemetry array in conjunction with small acoustic tags (including tags < 1.0 g) to track the fate of stocked juvenile cisco (Coregonus artedi) as part of a native species restoration effort in the Finger Lakes region of New York, USA. We used time-to-event modeling to characterize the survival function of stocked fish, where we infer mortality as the cessation of tag detections. Survival estimates revealed distinct stages of juvenile cisco mortality including high immediate post-release mortality, followed by a period of elevated mortality during an acclimation period. By characterizing mortality over time, the whole-lake biotelemetry effort provided information useful for adapting stocking practices that may improve survival of stocked fish, and ultimately the success of the species reintroduction effort. The combination of acoustic technology and time-to-event modeling to inform fish survival may have wide applicability across waterbodies where receiver arrays can be deployed at scale and where basic assumptions about population closure can be satisfied.

show abstract

Body condition in an endangered minnow is variable but not strongly related to environmental conditions

Archdeacon,

Dunnum

2024

Mar. Freshw. Res.

View full text Add to dashboard Cite

Seasonal patterns in body condition may help identify sensitive time periods or environmental stressors in fishes. Our objectives were to document spatiotemporal patterns of body condition of wild and hatchery-released Rio Grande silvery minnows (Hybognathus amarus), an endangered species endemic to the Rio Grande basin of North America. We collected fish weekly or bi-weekly from February to September, 2017 through 2019, in the Rio Grande, New Mexico, USA. Our time-series spanned an extreme drought year in 2018, allowing us to observe changes in body condition in relation to markedly different flow conditions. We collected body measurements from 2520 RGSM during the 3 years of our study. Spatiotemporal patterns in body condition were evident among and within years and sampling reaches, but within-sample variation in body condition was high. Annual patterns did not appear to be related to annual flow regime. Recaptured hatchery-reared fish were in slightly lower body condition, but followed the same seasonal patterns as did wild fish. Contrary to our expectations, body condition in both females and males was higher during the extreme drought year of 2018. Body condition may not be useful for identifying environmental stressors in small-bodied, short-lived fishes because individual variability is greater than spatial or temporal variation.

show abstract

Benefits of stocking fewer but larger individuals with implications for native fish recovery

Cited by 6 publications

References 48 publications

Hatchery supplementation increases potential spawning stock of Rio Grande Silvery Minnow after population bottlenecks

Hatchery supplementation increases potential spawning stock of Rio Grande Silvery Minnow after population bottlenecks

Whole-lake acoustic telemetry to evaluate survival of stocked juvenile fish

Body condition in an endangered minnow is variable but not strongly related to environmental conditions

Contact Info

Product

Resources

About