Theis, S.*, Ruppert, J. L. W. and M. S. Poesch. (2023) Coarse woody habitat use by local fish species and structural integrity of enhancements over time in a shallow northern boreal lake assessed in a Bayesian modeling approach. Ecological Solutions and Evidence.

Citation: Theis, S., Ruppert, J. L. W. and M. S. Poesch. (2023) Coarse woody habitat use by local fish species and structural integrity of enhancements over time in a shallow northern boreal lake assessed in a Bayesian modeling approach. Ecological Solutions and Evidence.

Abstract

  1. The introduction of coarse woody habitat has been a widely adopted management practice for restoring and enhancing freshwater aquatic ecosystems. Although responses of aquatic fish and invertebrate communities have largely been documented for lotic systems, benefits for lentic ecosystems have been mostly unevaluated.
  2. We tested the responses of fish populations to coarse woody habitat structures through a Bayesian modeling approach in a northern boreal lake in Alberta, Canada by enhancing a stretch of littoral zone with low structural complexity through introduction of coarse wood bundles and whole tree structures. The study site was split into three treatments, a Spaced treatment (structures 30 m apart), a Clustered treatment (structures 15 m apart), and an unaltered area (Control).
  3. Catch per unit effort and Catch per unit area data were collected over 2 years and posterior model predictions showed an increase in habitat use of the enhanced areas by spottail shiner – Notropis hudsonius; northern pike – Esox lucius; white sucker – Catostomus commersonii; brook stickleback – Culaea inconstans. No probable effect on overall fish condition, measured in Relative Weight, was linked to the enhancements.
  4. Across the two-year study, wood bundles degraded faster compared to the whole tree drops, coinciding with leveling off catch per unit effort and catch per unit area predictions near wood bundles, although catch predictions increased near the whole tree structures. Structural degradation set in as early as 1 week post construction for wood bundles and was mostly related to anchoring aspects.
  5. Results from our study provide evidence for the benefits provided by coarse woody habitat within northern boreal lake systems.  They furthermore highlight the short-lived nature of wood bundles built with biodegradable substances.  Methodologically our results offer evidence on the feasibility and utility of predictive modeling frameworks in addressing pseudoreplication and providing informative value for ecological studies.

Keywords: Fish Abundance, Northern Boreal Ecoregion, Habitat Enhancement, Restoration, Lake Ecosystems, Bayesian

*Lab members: Sebastian Theis, Jonathan Ruppert and Mark Poesch. Check out opportunities in the lab!

Theis, S.*, Ruppert, J.*, Shirton, J.* and M.S. Poesch (2022) Measuring beta diversity components and beneficial effects of coarse woody habitat introduction on invertebrate and macrophyte communities in a shallow northern boreal lake: implications for offsetting. Aquatic Ecology 56: 793-814.

Citation: Theis, S., Ruppert, J., Shirton, J. and M.S. Poesch (2022) Measuring beta diversity components and beneficial effects of coarse woody habitat introduction on invertebrate and macrophyte communities in a shallow northern boreal lake: implications for offsetting. Aquatic Ecology 56: 793-814.

Abstract

Structural habitat enhancement has been long established as a popular tool to counter habitat loss due from land-use and development. One enhancement approach is the introduction of Coarse Woody Habitat (CWH) to improve the establishment of macrophyte, macroinvertebrate, and fish communities. Here we assess the benefit of CWH in Northern boreal lakes in the context of mitigation projects. We constructed Coarse Woody Habitat structures in a structure-less littoral zone of Lake Steepbank within the Oil Sands Region of Alberta, Canada. Enhancement structures featured increased macrophyte and invertebrate richness and biomass compared to reference sites and pre-treatment assessments over the course of three years. Enhanced sites also retained improved richness (macrophytes), diversity (macroinvertebrates) and biomass (both), despite STIN loss and degradation of enhancement structures over time. Using beta diversity components, constituting richness agreement, community differentiation and site relationships, and testing their relative importance revealed that replacement was more dominant for invertebrates and increasing similarity more important for macrophyte communities post-enhancement. Our study shows the value of CWH addition for macroinvertebrate and macrophyte communities in what is otherwise a structure-less environment. Community changes over time showcase how beta diversity should be more strongly incorporated in restoration and enhancement studies to quantify community shifts that otherwise would not be captured in alternative diversity measures.

*Lab members: Sebastian Theis, Jonathan Ruppert, Jesse Shirton and Mark Poesch. Check out opportunities in the lab!

Card, J.*, Hasler, C., Ruppert, J.*Donadt, C.* and M.S. Poesch. (2020) A three-pass electrofishing removal strategy is not effective for eradication of Prussian Carp in a North American stream network. Journal of Fish and Wildlife Management 11(2): 485-493.

Citation: Card, J., Hasler, C., Ruppert, J., Donadt, C.* and M.S. Poesch. (2020) A three-pass electrofishing removal strategy is not effective for eradication of Prussian Carp in a North American stream network. Journal of Fish and Wildlife Management 11(2): 485-493. 

Abstract

Prussian Carp Carassius gibelio, also referred to as Gibel Carp, is a destructive aquatic invasive species, recently, found in Alberta Canada. Three-pass electrofishing is a potential approach to control some aquatic invasive fish species in stream habitats. The objectives of this study were to: 1) determine the efficacy of this strategy to control Prussian Carp in connected streams; and, 2) assess whether removal success was influenced by population size or the distance to the introduction site. We sampled sites using electrofishing in tributaries of the Red Deer River in both the summer and fall. Prussian Carp were detected at all sites prior to removal, with > 90 % probability of detection of this species within the first 120 m of electroshocking efforts. Overall, removal was deemed unsuccessful. We found that abundances of Prussian Carp were significantly higher post-removal. Removal success was significantly related to distance to the introduction site, suggesting that removal may be useful in targeted situations close to the edge of the invasion front. Additional removal and control strategies are needed by managers.

Highlighted in media (link here)

*Lab members:  Jamie Card, Jonathan Ruppert, Caitlyn Donadt and  Mark Poesch. Check out opportunities in the lab!

Theis, S.*, Ruppert, J.W.R*, Roberts, K.*, Koops, M., Minns, K. and M.S. Poesch. (2020) Compliance with and ecosystem function of biodiversity offsets in North American and European freshwaters. Conservation Biology 34(1) 41-53.

Citation: Theis, S.*, Ruppert, J.W.R*, Roberts, K.*, Koops, M., Minns, K. and M.S. Poesch. (2020) Compliance with and ecosystem function of biodiversity offsets in North American and European freshwaters. Conservation Biology 34(1) 41-53.

Abstract

Land‐use change via human development is a major driver of biodiversity loss. To reduce these impacts, billions of dollars are spent on biodiversity offsets. However, studies evaluating offset project effectiveness that examine components such as the overall compliance and function of projects remain rare. We reviewed 577 offsetting projects in freshwater ecosystems that included the metrics project size, type of aquatic system (e.g., wetland, creek), offsetting measure (e.g., enhancement, restoration, creation), and an assessment of the projects’ compliance and functional success. Project information was obtained from scientific and government databases and gray literature. Despite considerable investment in offsetting projects, crucial problems persisted. Although compliance and function were related to each other, a high level of compliance did not guarantee a high degree of function. However, large projects relative to area had better function than small projects. Function improved when projects targeted productivity or specific ecosystem features and when multiple complementary management targets were in place. Restorative measures were more likely to achieve targets than creating entirely new ecosystems. Altogether the relationships we found highlight specific ecological processes that may help improve offsetting outcomes.

Highlighted by CBC Radio(link).

*Lab members:  Sebastian Theis, Jonathan Ruppert, Karling Roberts and  Mark Poesch. Check out opportunities in the lab!

Rudolfsen, T.*, Ruppert, J.W.R.*, Davis, C., Taylor, R., Watkinson, D. and M.S. Poesch (2019) Habitat use and hybridization between the Rocky Mountain Sculpin (Cottus sp.) and Slimy Sculpin (Cottus cognatus). Freshwater Biology 64(3): 391-404.

Citation: Rudolfsen, T.*, Ruppert, J.W.R.*, Davis, C., Taylor, R., Watkinson, D. and M.S. Poesch (2019) Habitat use and hybridization between the Rocky Mountain Sculpin (Cottus sp.) and Slimy Sculpin (Cottus cognatus). Freshwater Biology 64(3): 391-404.

Abstract

Anthropogenic factors such as land-use change, pollution and climate change, can cause fragmentation and reduce the amount of habitat by altering preferred conditions. This process can also bring about novel species interactions and, in some cases, create or alter levels of hybridization between closely related species. We assessed the threat of hybridization to persistence of the Rocky Mountain Sculpin (Cottus sp.) and the Slimy Sculpin (Cottus cognatus) in the Flathead River drainage, British Columbia, Canada. Using 731 genetic samples, 10 polymorphic microsatellite loci and mitochondrial cytochrome C oxidase sequences, we assessed: (1) if there are differences in the distribution of Rocky Mountain Sculpin between contemporary and historical (35 years ago) records, (2) if hybridization is symmetrical in terms of sex specific parental contributions, and (3) if habitat preferences contribute to the distribution of pure parental and hybrid populations. We identified three hybrid locations and found that Rocky Mountain Sculpin have a distribution (1200 – 1902 m) that far exceeds the range limit reported 35 years ago (1200 – 1372 m). Additionally, hybrid mating appears to involve similar proportions of parents of both sexes from each species. Lastly, elevation, water conductivity, turbidity, and dissolved oxygen are significant factors predicting the presence of parental species. Only elevation was significant to hybrid presence. The contrasting associations of parental species with different habitat types appears to influence the extent and distribution of hybridization.

*Lab members:   Tyana Rudolfsen,  Jonathan Ruppert, Mark Poesch. Check out opportunities in the lab!

Ruppert, J.L.W.*, Hogg, J., and M.S. Poesch. (2018) Community assembly and the sustainability of habitat offsetting targets in the first compensation lake in the oil sands region in Alberta, Canada. Biological Conservation 219: 138-146.

Citation: Ruppert, J.L.W., Hogg, J., and M.S. Poesch. (2018) Community assembly and the sustainability of habitat offsetting targets in the first compensation lake in the oil sands region in Alberta, Canada. Biological Conservation 219: 138-146.

Abstract

Resource development can have a negative impact on species productivity and diversity through the loss and fragmentation of habitat. In many countries, developers are required by law to offset such impacts by replacing lost habitat or providing other forms of compensation. In the case of broad scale development, offsets often cannot be constructed to replace lost habitat “like-for-like” (i.e., they are not ecologically equivalent). In freshwater ecosystems, one approach to habitat offsetting is to create new lake ecosystems, called compensation lakes, to replace lost riverine habitat. In this study, we use a long-term data set (2008–2015) of fish and benthic invertebrate communities from Canada’s first compensation lake in the oil sands region of Alberta, to address (1) whether the assembly of the fish community has a trajectory that is influenced by management activities and (2) determine whether the community composition in the habitat offset is common in natural lake ecosystems within the region. We find a significant decline in the mean trophic level of the lake, where 61.9% of the variation in trophic level is explained by time indicating a strong structuring influence on fish communities. This outcome has enabled the compensation lake to meet overall and single species productivity targets, but we find that the species assemblage and composition is not common within the region. A combination of the founding species community and reduced connectivity of the lake has contributed to the current fish community structure, which may be problematic for the sustainability of the habitat offsetting targets. Our study highlights the need to establish multiple conservation guidelines, using both productivity and diversity based metrics, to provide the best ecological equivalency, which can produce better function, resilience and health within focal species communities in habitat offsets that are not “like-for-like.”

*Lab members: Jonathan RuppertMark Poesch. Check out opportunities in the lab!

Graphical Abstract

Figure – Changes in Freshwater Communities Through Time. Shown is teh annual (A) mean density and (B) species diversity of fish species in Horizon Lake during the monitoring period of 2008-2015. Also shown is the corresponding annual (C) mean density and (D) diversity of bentic invertebrates during that period (EK- Ekman Grab; KN – Kick Net).

Ruppert, J.L.W.*, Docherty,C.*, Rudolfsen, T.*, Neufeld, K.*, Hamilton, K.*, MacPherson, L. and M.S. Poesch. (2017) Native North American freshwater species get out of the way: Prussian Carp (Carassius gibelio) establishment impacts both fish and macroinvertebrate communities. Royal Society Open Science 4: 170400.

Citation: Ruppert, J.L.W.*, Docherty,C.*, Rudolfsen, T.*, Neufeld, K.*, Hamilton, K.*, MacPherson, L. and M.S. Poesch. (2017) Native North American freshwater species get out of the way: Prussian Carp (Carassius gibelio) establishment impacts both fish and macroinvertebrate communities. Royal Society Open Science 4: 170400.

Abstract

Prussian carp (Carassius gibelio) are one of the most noxious non-native species in Eurasia. Recently, Prussian carp, a nonnative freshwater fish species, were genetically confirmed in Alberta, Canada and have been rapidly expanding their range in North America since establishment. Given their rapid range expansion, there is an increasing need to determine how Prussian carp may impact native species. We assessed the severity of the Prussian carp invasion by (i) determining their impact on fish communities, (ii) assessing their impact on benthic invertebrate communities, (iii) evaluating if Prussian carp alter abiotic conditions, and (iv) identifying where we find higher abundances of Prussian carp. When Prussian carp were established, we found significant changes to the fish community. Correspondingly, the degree of impact to benthic invertebrate communities was related to the stage of invasion (none, early or recent), where changes in fish communities were significantly concordant with changes in benthic invertebrate communities. Finally, we found that higher abundances of Prussian carp were significantly associated with lower abundances of a majority of native fish species. Altogether, using three lines of evidence, we determine that Prussian carp can have wide-ranging impacts on freshwater ecosystems in North America, pressing the need for management intervention.

*Lab members: Jonathan RuppertCassandra DochertyTyana RudolfsenKenton NeufeldKyle HamiltonMark Poesch. Check out opportunities in the lab!

Docherty, C.*, Ruppert, J.*, Rudolfsen, T.*, Hamann, A., and Poesch, M.S. (2017) Assessing the spread and potential impact of Prussian Carp (Carassius gibelio Bloch, 1782) to freshwater fishes in western North America. BioInvasions Records 6: 291-296.

Citation: Docherty, C.*, Ruppert, J.*, Rudolfsen, T.*, Hamann, A., and Poesch, M.S. 2017. Assessing the spread and potential impact of Prussian Carp (Carassius gibelio Bloch, 1782) to freshwater fishes in western North America. BioInvasions Records 6: 291-296.

Abstract

Prussian Carp (Carassius gibelio Bloch, 1782) is one of the most successful invasive species in Eurasia. Recently, Prussian Carp were genetically confirmed in Alberta, Canada, documenting the first detection of this species in North America. Given the close morphological similarity to their sister species, the Goldfish (Carassius auratus Linnaeus, 1758), it is likely that this species has been undetected for some time. We document the spread of Prussian Carp since arrival (circa 2000), and contribute a trait-based risk assessment to potential recipient communities in western North America. Using a meta-analysis of geo-referenced fisheries data in conjunction with original sampling in 2014, we show that the Prussian Carp range has increased by eight- to eleven-fold over 15 years in Alberta at a rate of approximately 233–1,250 km2 per year. Range expansions in the near future are possible through the Saskatchewan River drainage and south into the Missouri River basin, with easily accessible routes to Midwestern North America through irrigation canals. We show high life history trait overlap with other successful invasive species, such as Goldfish and Common Carp (Cyprinus carpio Linnaeus, 1758). Additionally, there was high life history trait overlap with several species of native sunfish (Centrarchidae) and suckers (Catostomidae). This study highlights Prussian Carp’s potential to widely impact North American freshwater ecosystems and to successfully compete with native taxa. Considered one of the worst invaders in Eurasia, the arrival of Prussian Carp in North America poses serious concern for fisheries managers. There is an urgent need to develop management plans before further range expansion and disruption of freshwater ecosystems by this new invasive species.

*Lab members: Cassandra DochertyJonathan RuppertTyana RudolfsenMark Poesch. Check out opportunities in the lab!

Spread of Prussian Carp in Alberta, Canada

Veillard, M.F.*, Ruppert, J.L.W.*, Tierney, K., Watkinson, D., and M.S. Poesch. (2017) Comparative swimming and station-holding ability of the threatened Rocky Mountain Sculpin (Cottus sp.) from four hydrologically distinct rivers. Conservation Physiology 5: 1-12.

Citation: Veillard, M.F.*, Ruppert, J.L.W.*, Tierney, K., Watkinson, D., and Poesch, M.S. 2017. Comparative swimming and station-holding ability of the threatened Rocky Mountain Sculpin (Cottus sp.) from four hydrologically distinct rivers. Conservation Physiology 5: 1-12.

Abstract

Hydrologic alterations, such as dams, culverts or diversions, can introduce new selection pressures on freshwater fishes, where they are required to adapt to novel environmental conditions. Our study investigated how species adapt to natural and altered stream flow, where we use the threatened Rocky Mountain Sculpin (Cottus sp.) as a model organism. We compared the swimming and station-holding performance of Rocky Mountain Sculpin from four different hydrologic regimes in Alberta and British Columbia, including the North Milk River, a system that experiences increased flows from a large-scale diversion. We measured the slip (Uslip) and failure (Uburst) velocities over three constant acceleration test trials. Uslipwas defined as the point at which individuals required the addition of bursting or swimming to maintain position. Uburst was defined as the point at which individuals were unable to hold position in the swimming chamber through swimming, bursting or holding techniques without fully or partially resting on the electrified back plate. We found individuals from the Flathead River in British Columbia (with the highest natural flow) failed at significantly higher Uburstvelocities than fish from the southern Albertan populations. However, there was no relationship between peak hydrologic flow from the natal river and Uburst or Uslip. Further, Uburst velocities decreased from 51.8 cm s−1 (7.2 BL s−1) to 45.6 cm s−1 (6.3 BL s−1) by the third consecutive test suggesting the use of anaerobic metabolism. Uslip was not different between trials suggesting the use of aerobic metabolism in station-holding behaviours (Uslip). Moreover, we found no significant differences in individuals from the altered North Milk River system. Finally, individual caudal morphological characteristics were related to both slip and failure velocities. Our study contributes to the conservation of Rocky Mountain Sculpin by providing the first documentation of swimming and station-holding abilities of this benthic fish.

*Lab members: Marie VeillardJonathan RuppertMark Poesch. Check out opportunities in the lab!

Difference in Swim Performance Across Populations of Rocky Mountain Sculpin. Shown are Tukey contrasts (estimate +/- 95% confidence intervals) between rivers (top row) and constant acceleration trial (CAT) numbers (bottom row) for failure (Uburst) and slip (Uslip) velocities from linear effects model. Significant differences are noted in yellow; Rivers are abbreviated as: Flathead River (FH), St. Mary River (SM), Lee Creek (LC) and North Milk River (NM).

Thayer, D.*, Ruppert, J.L.W., Watkinson, D., Clayton, T. and M.S. Poesch. (2017) Identifying temporal bottlenecks for the conservation of large-bodied fishes: Lake Sturgeon (Acipenser fluvescens) show highly restricted movement and habitat-use overwinter. Global Ecology and Conservation 10: 194-205.

Citation: Thayer, D.*, Ruppert, J.L.W., Watkinson, D., Clayton, T. and M.S. Poesch. (2017) Identifying temporal bottlenecks for the conservation of large-bodied fishes: Lake Sturgeon (Acipenser fluvescens) show highly restricted movement and habitat-use overwinter. Global Ecology and Conservation 10: 194-205.

Abstract

The relationship between species’ size and home range size has been well studied. In practice, home range may provide a good surrogate of broad spatial coverage needed for species conservation, however, many species can show restricted movement during critical life stages, such as breeding and over-wintering. This suggests the existence of either a behavioral or habitat mediated ‘temporal bottleneck,’ where restricted or sedentary movement can make populations more susceptible to harm during specific life stages. Here, we study over-winter movement and habitat use of Lake Sturgeon (Acipenser fulvescens), the largest freshwater fish in North America. We monitored over-winter movement of 86 fish using a hydro-acoustic receiver array in the South Saskatchewan River, Canada. Overall, 20 fish remained within our study system throughout the winter. Lake Sturgeon showed strong aggregation and sedentary movement over-winter, demonstrating a temporal bottleneck. Movement was highly restricted during ice-on periods (ranging from 0.9 km/day in November and April to 0.2 km/day in mid-November to mid-March), with Lake Sturgeon seeking deeper, slower pools. We also show that Lake Sturgeon have strong aggregation behavior, where distance to conspecifics decreased (from 575 to 313 m) in preparation for and during ice-on periods. Although the Lake Sturgeon we studied had access to 1100 kilometers of unfragmented riverine habitat, we show that during the over-winter period Lake Sturgeon utilized a single, deep pool (<0.1% of available habitat). The temporal discrepancy between mobile and sedentary behaviors in Lake Sturgeon suggest adaptive management is needed with more localized focus during periods of temporal bottlenecks, even for large-bodied species.

*Lab members: Donnette ThayerJonathan RuppertMark Poesch. Check out opportunities in the lab!

Monthly core (C) and range (R) extent kernel density maps for: A) November, B) December, C) January, D) February, E) March, and F) April. Black lines are core range (50% percentile), broken lines range (90th percentile) extent.