Geology topics

Sophia Marie Bonjour

Publications and source records attributed to Sophia Marie Bonjour.

8 recordsLinked to original sources

USGS2026

Beyond barriers: Fish assemblage recovery following dam removal on the Cuyahoga River, a Lake Erie tributary

Dam removals are increasing globally, yet ecological outcomes vary widely because biological recovery depends on post-removal connectivity and access to source populations. We evaluated how multiple dam removals and remaining fragmentation influenced fish assemblage recovery in the Cuyahoga River (OH, United States), a historically polluted Great Lakes tributary now undergoing extensive remediation and restoration. Using fish assemblage data collected from 1984 to 2024 across reaches downstream, within, and upstream of the Gorge Plant Dam (GPD), an 18-m barrier slated for removal, we quantified spatial and temporal change with ordination, trajectory, and distance-based redundancy analyses. Downstream assemblages showed a clear shift through time and gained 15 newly detected taxa after the 2020 Brecksville Dam removal increased longitudinal connectivity to Lake Erie by 39 river kilometers, more than doubling free-flowing habitat below GPD. In contrast, assemblages upstream of GPD exhibited limited change and patterns consistent with redistribution of resident species rather than colonization-driven turnover. Across the full time series, site position relative to GPD and the rate of dam removal were the strongest predictors of assemblage variation, with habitat gradients (e.g. depth, velocity, turbidity, and canopy cover) further differentiating reaches. Together, these results show that connectivity and barrier position shape assemblage recovery following dam removal. Most newly detected taxa downstream were native, though three were nonnative, indicating trade-offs between recolonization and nonnative spread.

Ohio↗

USGS2026

Restoration in motion: Expanded migration and distribution of silver redhorse Moxostoma anisurum and shorthead redhorse M. macrolepidotum

Habitat fragmentation poses a significant threat to migratory species. Dams are a common form of fragmentation, and recent restoration efforts around the Great Lakes have prioritized dam removal. We used acoustic telemetry to describe migratory movements of two redhorse species in the Sandusky and Cuyahoga rivers, Ohio, USA in relationship to habitat reconnection. Shorthead redhorse ( Moxostoma macrolepidotum ) typically migrated from both rivers into Lake Erie between May and July, moving 40–248 km straight-line distance from the river before returning the following spring. We recorded individual cumulative distances up to 809 km between spawning seasons. Shorthead redhorse demonstrated tributary fidelity, but individuals from both rivers co-occurred along southern Lake Erie. Silver redhorse ( M. anisurum ) largely remained in their tagging tributary watersheds year-round. Cuyahoga River silver redhorse moved upstream from March to April 28.8 km on average and passed upstream of the historical Brecksville Dam (removed in 2020), occasionally reaching the next upstream dam. Telemetry data revealed redhorse use of newly available habitat upstream of dam removals and previously undescribed long-range adfluvial migration by shorthead redhorse.

Ohio↗

USGS2025

Staying alive: Post-translocation apparent survival of fishes in headwater springs following drought

Objective Increasing fragmentation from constructed barriers, increased water use, and climate change limits the resiliency of stream fish metapopulations by reducing colonization. Management actions such as stocking or translocating fish may help contribute to the resilience of isolated habitats and increase redundancy of populations in intermittent stream networks. Our objective was to determine whether translocating fish into prairie headwater refuges could reestablish or supplement isolated populations. Methods We examined apparent survival and probability of detection of four native, small-bodied fishes that were translocated in 2022 and 2023 to prairie headwater refuges that were affected by a severe drought and experienced slow recovery of their fish assemblages. All the fish were marked with passive integrated transponder tags, allowing us to use a mark–recapture framework to track the fate of these fish. Results Apparent survival was predicted by an interaction between time and translocation site, indicating an important consideration of environmental factors. Approximately one-quarter of the fish remained at site A through the summer of both years, whereas estimates were near zero at site B in both years and mixed across years at site C. The decreases in apparent survival probabilities following flow events suggest that fish may be emigrating during these periods of reconnection. During the lower flow year, more fish remained at the headwater sites and young-of-year fish were captured during long-term sampling, suggesting that the translocated fish reproduced. Conclusions The success of translocation projects will depend on a variety of factors, including management goals, habitat, and hydrology, but the initially high survival reported in this study is encouraging. Difficulties with examining the movement of small fish during hydrologic events limited our conclusions about the relative contributions of mortality and emigration to apparent survival estimates. Despite low yearly apparent survival, we found evidence of reproduction from translocated fish, suggesting that the reestablishment of a viable population is possible.

North American Journal of Fisheries Management↗

USGS2025

Long-term surgery survival, body condition effects, and incision healing of Silver Carp and buffalo species comparing sedation methods across seasons

Objective Internal tagging for telemetry studies requires invasive surgery procedures, necessitating sufficient sedation to support animal welfare. Challenges with existing chemical sedatives have resulted in technological alternatives, including electrosedation, with these newer methods less extensively studied. Our primary objective was to understand long-term survival, body-condition effects, and incision healing after surgical implantation of an imitation telemetry transmitter under three different sedation techniques. Methods We collected Silver Carp Hypophthalmichthys molitrix and buffalo Ictiobus spp. from the Missouri River watershed in 2022 and 2023, during each of the four seasons. One of three sedation techniques was applied: electric fish handling gloves, tricaine methanesulfonate (MS-222), and eugenol. Additionally, we observed a group of fish that were unsedated but subjected to handling similar to that experienced during surgery. Fish were monitored to determine the effects of treatment, individual characteristics, surgery characteristics, and time-varying environmental factors on survival, body condition, and incision healing over 69- to 85-d holding periods. Results Long-term survival was higher for buffalo (86%) than Silver Carp (57%), with the fewest mortalities during the winter trial and most in summer, but sedation treatment did not affect survival. Smaller fish had a greater risk of mortality but better incision healing. Incision healing scores improved in warmer temperatures. Conclusions Difference in seasonal effects on survival and healing indicate a need to consider trade-offs when scheduling tagging for projects. However, a lack of difference in survival among treatments, including the group that was handled but did not undergo surgery, suggests no advantage of one sedative over another, but handling impacts may require more consideration.

Transactions of the American Fishery Society↗

USGS2025

Grass carp (Ctenopharyngodon idella) movement states and backwater use can inform removal efforts

Expansion of grass carp ( Ctenopharyngodon idella ) within the Laurentian Great Lakes poses significant ecological and economic risks. Suppression efforts to remove grass carp have increased to curtail population growth, but capture efficiency remains low. One management challenge is the lack of understanding how this invasive species is using its novel habitats in the Great Lakes. This study aimed to identify spatiotemporal patterns in grass carp behavior and backwater use that could be exploited by management efforts, including removal. We used acoustic telemetry to examine when grass carp occurred in areas vulnerable to removal by boat electrofishing in the Sandusky River, Ohio, USA. Hidden Markov models were used to categorize behavioral states and evaluate their relationships with environmental factors. Best performing 2-state and 3-state hidden Markov models included proximity to backwater as a factor in state-dependent step length and transition probability between states, with a higher probability of being in less mobile states during the middle of the day and in backwaters. For the 2-state model, this less mobile state was also more common during warmer temperatures. Distinct diel patterns and backwater use identified in this study provide critical insights for improving management. Model results suggest that current removal efforts, focused primarily on the mainstem of the river, may benefit from adjustments in both timing and removal gear. The findings raise further questions about unobserved behaviors contributing to state assignment and sufficiently flexible adaptive management strategies to account for individual variation in grass carp behavior.

Ohio↗

USGS2024

Individual return patterns of spawning flannelmouth sucker (Catostomus latipinnis) to a desert river tributary

Tributaries provide temporal and spatial habitat heterogeneity in river networks that can be critical for parts of the life history of a species. Tributary fidelity can benefit individual fish undergoing spawning migrations by reducing time and energy spent exploring new areas and leveraging previous experience, but anthropogenic activities that fragment or degrade these systems can eliminate those benefits. We used multistate models based on passive integrated transponder (PIT) detection data from 2013 to 2023 to estimate the proportion of flannelmouth suckers ( Catostomus latipinnis ) migrating to a tributary, McElmo Creek, from the mainstem San Juan River for spawning. Survival varied among years and among states. The top model for migration probability included sex, with males slightly more likely to migrate (0.93 vs 0.90), and the next model identified interannual variation in migration probability ranging from 0.875 to 0.999 across years, indicating high site fidelity. Individuals showed consistency in relative arrival timing across years, with the highest correlation generally during years with greater spring discharge and extended tributary residence time. Successful tributary spawning may be important for the maintenance of the mainstem San Juan River flannelmouth sucker population, but site fidelity may be maladaptive where tributaries are vulnerable to human alterations.

Arizona, Colorado, New Mexico, Utah↗

USGS2024

Handling effects on dispersal of PIT-tagged Flannelmouth Sucker

Objective Handling and tagging migrating fish might alter their behavior, limiting inference from mark–recapture studies. Posthandling flight of tributary spawning Flannelmouth Sucker Catostomus latipinnis was previously identified in Coal Creek in the upper Colorado River basin. Our objective was to determine if similar issues were present at McElmo Creek in the San Juan River basin. Methods We compared emigration timing of Flannelmouth Sucker that had been handled and tagged with passive integrated transponder tags during their tributary spawning run to individuals tagged in previous years and detected both entering and exiting the tributary. Linear mixed-effects models were used to examine intrinsic and extrinsic factors contributing to exit timing. Result Sex and tagging year were associated with emigration timing, but handling did not result in posthandling flight from McElmo Creek. Females exited the tributary ~3 days before males, and larger fish emigrated earlier than smaller adults. Conclusion Differences in capture technique and timing, available spawning habitat, and fish motivation across river systems may contribute to differences in posthandling emigration of tributary spawning Flannelmouth Sucker.

Colorado, Utah↗

USGS2024

Capturing potential: Leveraging grass carp behavior Ctenopharyngodon idella for enhanced removal

Effective management of invasive species benefits from a comprehensive understanding of the species’ behavior and interactions with the invaded system. We investigated temporal dynamics of telemetry detections and the potential utility of a traitor approach for informing response efforts to the invasive grass carp ( Ctenopharyngodon idella ) population in the Sandusky River, a major tributary to Lake Erie. Telemetered grass carp exhibited heightened activity at night and early morning, suggesting that capture and removal be more effective during these time periods. Analysis of catch per unit effort (CPUE) across different removal methods, trammel nets, electrofishing, and hoop nets. suggested that incorporating the traitor approach could improve capture. Low catchability values (<0.026), based on the number of telemetered grass carp present in the river on a weekly basis and the number of those telemetered fish captured, suggest the species is difficult to capture. Optimizing response effort efficiency is important and refining catchability estimates will lessen errors in population models and improve interpretation of low CPUE data. Results from generalized additive models suggest capture could be improved using telemetry data, night removals, and by attempting exploratory removal efforts in fall and winter months. By incorporating telemetry data and acknowledging the complexities of grass carp behavior and ecology, we found that a multifaceted and data-driven approach to invasive species control could be beneficial, ultimately promoting conservation and sustainability in dynamic ecosystems like Lake Erie.

Ohio↗