Tag Archives: ConservationArt

Veillard, M., Watkinson, D. and M. S. Poesch. (2026). Biotic and abiotic factors and their interaction influence the seasonal movement patterns of a dispersal limited benthic species. Environmental Biology of Fishes 109:86.

Abstract:

Dispersal is an important mechanism linked with population viability. Increases in species-specific dispersal allow for improved connectivity between habitat patches and populations. Here, we seek to understand the role of both biotic and abiotic factors, and their interactions, in influencing the movement of the recently identified and federally threatened Rocky Mountain sculpin (Cottus sp.). We conducted a mark-recapture study in a 400 m reach of Lee Creek in Alberta, Canada, using passive integrated transponder and visible implant elastomer tags across approximately 4 months. Boosted regression tree models were used to assess the movement of (1) all recaptured individuals (global model) and (2) only mobile individuals (movement only model) in response to abiotic and biotic factors. Biotic factors, such as congeners at the destination (8.7%), congeners at the origin (8.0%), and competitors at the origin (7.2%) were the most important variables for predicting movement in the global model. Alternatively, cobble (18.7%) followed by biotic factors including congeners at the origin (9.6%) and competitors at the origin (9.1%) were the most important variables selected in the movement only model. Biotic and abiotic factors showed strong interactions, providing a clear example of the importance of competition in the understanding of movement. Although the vast majority of restoration activities for endangered species are aimed at abiotic (i.e. habitat-related) factors, this study shows how these may be limited without considering biotic interactions, such as the role of inter- and intraspecific competition.

Citation: Veillard, M., Watkinson, D. and M. S. Poesch. (2026). Biotic and abiotic factors and their interaction influence the seasonal movement patterns of a dispersal limited benthic species. Environmental Biology of Fishes 109:86. DOI: https://doi.org/10.1007/s10641-026-01841-9

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Medinski, N.A.*, Maitland, B.M.*, Jardine, T.D., Drake, D.A.R. and M.S. Poesch (2022) A catastrophic coal mine spill in the Athabasca River watershed induces isotopic niche shifts in stream biota including an endangered rainbow trout ecotype. Canadian Journal for Fisheries and Aquatic Sciences 79(8): 1321-1334.

*Lab members: Marie Veillard and Mark Poesch. Check out opportunities in the lab!

Pallard J., Jardine, T. and M. S. Poesch. (In Press) Altered resource use by threaten Bull Trout (Salvelinus confluentus) amid competition from two non-native salmonids. Journal of Fish Biology.

Abstract

  1. Introduction of non-native species contributes to the global decline of freshwater fishes by disrupting the diet and resources of native species through competition. Despite potential for non-native trout (Family: Salmonidae) to compete with native trout, non-native trout species have been widely introduced worldwide to support recreational fishing.
  2. In this study, we examined resource use by native Bull Trout (Salvelinus confluentus), a Threatened species, and non-native Brook Trout (Salvelinus fontinalis) and Brown Trout (Salmo trutta) in headwater streams in Alberta, Canada. Our objective was to investigate potential for competition and its implications for Bull Trout populations. To assess changes in diet, we used stable isotope analysis.
  3. Brook Trout and Brown Trout had higher trophic positions (3.49 ± 0.02 and 3.53 ± 0.02) and greater proportions of terrestrial resources in their diets (0.53 ± 0.02, 0.54 ± 0.03) than Bull Trout (TP = 3.38 ± 0.02, proportion terrestrial = 0.36 ± 0.02) suggesting the non-native species may outcompete Bull Trout for preferred resources and larger prey. Moreover, a relatively wide isotopic niche of Bull Trout led to a lack of niche partitioning and substantial overlap in niche utilization between sympatric Brook Trout and Bull Trout, supporting the potential for future niche displacement, particularly in scenarios where resources are scarce.
  4. These findings underscore the importance of monitoring and managing the invasion of non-native salmonids in streams where native salmonid populations exist, and the challenges in understanding multi-species interactions in dynamic habitats. It highlights the need for effective fisheries management and conservation efforts in regions where native freshwater fishes are facing population declines.

Citation: Pallard J., Jardine, T. and S. Poesch. (In Press) Altered resource use by threaten Bull Trout (Salvelinus confluentus) amid competition from two non-native salmonids. Journal of Fish Biology.

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Medinski, N.A.*, Maitland, B.M.*, Jardine, T.D., Drake, D.A.R. and M.S. Poesch (2022) A catastrophic coal mine spill in the Athabasca River watershed induces isotopic niche shifts in stream biota including an endangered rainbow trout ecotype. Canadian Journal for Fisheries and Aquatic Sciences 79(8): 1321-1334.

*Lab members: Jacquie Pallard and Mark Poesch. Check out opportunities in the lab!

Tierney K. B., Smith J., Veillard M., Steffler M. V. and M. S. Poesch. (2025). Subpopulations of an imperilled freshwater fish shows behavioral adaptation that informs survival in the Anthropocene. Canadian Journal of Fisheries and Aquatic Science 82:1-10.

Abstract:

Freshwater fishes are amongst the most threatened group of animals. Changes in river flows are an important driver in this. To gauge the ability of a common freshwater fish to respond to altered flows, we examined how sculpins from rivers with different flow regimes behaviourally responded to increasing water speeds. We chose the imperiled Rocky Mountain Sculpin, since within their restricted geographic distribution, there are endemic subpopulations that inhabit rivers with high and low flow volumes, and an introduced subpopulation that inhabits a river with moderate flow volume. Sculpins were collected from these rivers, acclimated to laboratory conditions, and their swimming behaviour was observed in a three-chambered flume. Swimming activity did not differ between the subpopulations, but stream place preference did: sculpins from high flow volume preferred upstream, while sculpins from moderate flow volume preferred downstream, and sculpins from low flow volume were indifferent. An exploratory phenotype was present in each subpopulation. This study suggests that altered river flows may change upstream and downstream place preference, which in turn could affect species distributions and interactions.

Citation: Tierney K. B., Smith J., Veillard M., Steffler M. V. and M. S. Poesch. (2025). Subpopulations of an imperilled freshwater fish shows behavioral adaptation that informs survival in the Anthropocene. Canadian Journal of Fisheries and Aquatic Science 82:1-10.

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Medinski, N.A.*, Maitland, B.M.*, Jardine, T.D., Drake, D.A.R. and M.S. Poesch (2022) A catastrophic coal mine spill in the Athabasca River watershed induces isotopic niche shifts in stream biota including an endangered rainbow trout ecotype. Canadian Journal for Fisheries and Aquatic Sciences 79(8): 1321-1334.

*Lab members: Marie Veillard and Mark Poesch. Check out opportunities in the lab!

Pallard J. and M. S. Poesch. (2025) Factors affecting Bull Trout (Salvelinus confluentus) abundance and potential displacement by non-native Brook Trout (Salvelinus fontinalis) and Brown Trout (Salmo trutta) in headwater streams. Aquatic Conservation: Marine and Freshwater Ecosystems 35(9): e70227.

Abstract

The invasion of non-native fish species poses a major threat to native salmonids in freshwater ecosystems. We investigated the potential displacement of threatened Bull Trout (Salvelinus confluentus) by non-native Brook Trout (Salvelinus fontinalis) and Brown Trout (Salmo trutta) in 44 headwater streams across Alberta, Canada. Using electrofishing surveys and a combination of single- and multi-species N-mixture models, we examined how fish abundance responds to instream habitat characteristics, landscape features, and species interactions, while accounting for imperfect detection. Results revealed that reduced Bull Trout abundance was correlated with the abundance of Brook Trout in cold streams (mean August temperature <11°C) that lack habitat complexity, particularly where large woody debris and heterogeneous channel features are limited. Conversely, Brown Trout were associated with reduced Bull Trout abundance in larger, lower-elevation systems, likely due to competitive dominance in deeper and slower habitats. These findings highlight that temperature alone likely does not dictate displacement risk; and that habitat structure and species-specific traits also play critical roles. Management strategies should prioritize the protection of cold, structurally complex streams and consider targeted removals or exclusion strategies to limit further invasion. Habitat restoration and assisted colonization to suitable, non-invaded refugia may further enhance Bull Trout conservation under ongoing climate and land-use change.

Citation: Pallard J. and M. S. Poesch. (2025) Factors affecting Bull Trout (Salvelinus confluentus) abundance and potential displacement by non-native Brook Trout (Salvelinus fontinalis) and Brown Trout (Salmo trutta) in headwater streams. Aquatic Conservation: Marine and Freshwater Ecosystems 35(9): e70227. DOI: 10.1002/aqc.70227.

Also Read:

Medinski, N.A.*, Maitland, B.M.*, Jardine, T.D., Drake, D.A.R. and M.S. Poesch (2022) A catastrophic coal mine spill in the Athabasca River watershed induces isotopic niche shifts in stream biota including an endangered rainbow trout ecotype. Canadian Journal for Fisheries and Aquatic Sciences 79(8): 1321-1334.

*Lab members: Jacquie Pallard and Mark Poesch. Check out opportunities in the lab!

Hambrook J., Kimmel N., Robinson R., Foster D., Poesch M.S. and P. Hanington. (2025) Development, validation and implementation of eDNA-focused qPCR assays to detect and distinguish between Goldfish (Carassius auratus) and Prussian Carp (Carassius gibelio). Environmental DNA 7(2): e70092.

Abstract: 

The ability to accurately detect harmful aquatic invasive species in a species-specific manner is crucial to monitoring and management efforts. The Canadian province of Alberta currently harbors North America’s only invasive Prussian Carp populations, in addition to invasive Goldfish populations. The ability to quickly and accurately distinguish between these phenotypically similar fish, while also determining their presence in various waterbodies, is important in tracking invasions. In this work, we develop a cytochrome B–based assay, as well as an ND2-based assay to distinguish between these two fish. The 84-bp-long CytB assay featured a limit of detection of 5.8 and 4.8 copies/sample for Prussian Carp and Goldfish, respectively, while the 95-bp-long ND2 assay featured LODs of 6.3 and 1.6 copies/sample, respectively. We demonstrate that each of these assays fails to amplify these markers in closely related fish species common to Alberta. They also fail to amplify key invasive carp species, apart from the Goldfish ND2 assay, which cross-reacts with Common Carp. We then implement these assays and find 13 Goldfish and 47 Prussian Carp environmental DNA detection events throughout the Canadian province of Alberta. Finally, we show that assays broadly agree with visual observation data gathered from various reporting mechanisms, highlighting their validity in a monitoring program.

Citation: Hambrook J., Kimmel N., Robinson R., Foster D., Poesch M.S. and P. Hanington. (2025) Development, validation and implementation of eDNA-focused qPCR assays to detect and distinguish between Goldfish (Carassius auratus) and Prussian Carp (Carassius gibelio). Environmental DNA 7(2): e70092. 

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Veilleux, H., McPherson, M.*, Cott, P., Poesch, M., S., Glover, C., and G. Goss. (2025) Environmental DNA as a tool to detect Arctic grayling and their habitat preferences in the Northwest Territories, Canada. Arctic Science 11: 1-12.

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

Veilleux, H., McPherson, M.*, Cott, P., Poesch, M., S., Glover, C., and G. Goss. (2025) Environmental DNA as a tool to detect Arctic grayling and their habitat preferences in the Northwest Territories, Canada. Arctic Science 11: 1-12.

Abstract: 

Environmental DNA (eDNA) assays represent a non-invasive approach for biomonitoring. To assess Arctic grayling (Thymallus arcticus) populations in the Little Nahanni watershed of Northwest Territories (NWT), Canada, an eDNA assay that has been previously validated for use in fish of the Beringia lineage was used in conjunction with traditional survey methods (i.e., electrofishing). Forty-six 100-metre reaches of streams were assessed in August 2015. The assay successfully detected Arctic grayling of the Nahanni lineage, with an eDNA signal recorded at each of the 17 sites in which Arctic grayling were observed by traditional fish surveys, but also at 3 of the 29 sites where Arctic grayling were not observed. The presence of eDNA was related to habitat metrics via Random Forest and correlation analyses. Riffles and water temperature were identified as being predictive of Arctic grayling eDNA abundance; however, no significant relationship between eDNA abundance and biomass proxies (fish abundance and fork length metrics) could be established. The high congruence between traditional approaches and eDNA surveys suggests adoption of the latter method will enhance the temporal and spatial acuity of biomonitoring, thereby improving field assessment of Arctic grayling populations and contributing towards more effective conservation management of this species.

Citation: Veilleux, H., McPherson, M., Cott, P., Poesch, M., S., Glover, C., and G. Goss. (2025) Environmental DNA as a tool to detect Arctic grayling and their habitat preferences in the Northwest Territories, Canada. Arctic Science 11: 1-12.

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McPherson, M.*, Lewis, J.B., Cott, P.B., Baker, L.F., Mochnacz, N.J. Swanson, H.K., and S. Poesch. (2023) Habitat use by fluvial Arctic Grayling (Thymallus arcticus) across life stages in northern mountain streams. Environmental Biology of Fishes 106: 1001-1020.

*Lab members: Morag McPherson and Mark Poesch. Check out opportunities in the lab!

Serbu, J. A., St. Louis, V. L., Emmerton, C. A., Tank S., Criscitello, A., Silins, U., Bhatia, M., Cavaco, M., Christenson, C., Cooke, C., Drapeau, H., Enns, S. J., Flett, J., Holland, K., Lavelle-Whiffen, J., Ma, M., Muir, C., Poesch, M. S., and J. Shin. (2023). A comprehensive biogeochemical assessment of climate-threatened glacial river headwaters on the eastern slopes of the Canadian Rocky Mountains. JGR Biogeosciences 129: e2023JG007745. 

Abstract:

Climate change is driving the loss of alpine glaciers globally, yet investigations about the health of rivers stemming from them are few. Here we provide an overview assessment of a biogeochemical dataset containing 200+ parameters that we collected between 2019-2021 from the headwaters of three such rivers (Sunwapta-Athabasca, North Saskatchewan, and Bow) which originate from the glacierized eastern slopes of the Canadian Rocky Mountains. We used regional hydrometric datasets to accurately model discharge at our sampling sites. We created a Local Meteoric Water Line (LMWL) using riverine water isotope signatures and compared it to regional rain, snow, and glacial ice signatures we also collected. Principal component analyses of river physicochemical measures revealed distance from glacier explained more data variability than the spatiotemporal factors season, year, or river. Discharge, chemical concentrations, and watershed areas were then used to model site-specific open water season yields for 25 parameters. Chemical yields followed what would generally be expected along river continuums from glacierized to montane altitudinal life zones, with landscape characteristics acting as chemical sources and sinks. For instance, particulate chemical yields were generally highest near source glaciers with proglacial lakes acting as settling ponds, whereas most dissolved yields varied by parameter and site. As these headwaters continue to evolve with glacier mass loss, the dataset and analyses presented here can be used as a contemporary baseline to mark future change against. Further, following this initial assessment of our dataset, we encourage others to mine it for additional biogeochemical studies.

Citation: Serbu, J. A., St. Louis, V. L., Emmerton, C. A., Tank S., Criscitello, A., Silins, U., Bhatia, M., Cavaco, M., Christenson, C., Cooke, C., Drapeau, H., Enns, S. J., Flett, J., Holland, K., Lavelle-Whiffen, J., Ma, M., Muir, C., Poesch, M. S., and J. Shin. (2023). A comprehensive biogeochemical assessment of climate-threatened glacial river headwaters on the eastern slopes of the Canadian Rocky Mountains. JGR Biogeosciences 129: e2023JG007745. 

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Theis, S.*  Castellanos D.A., Hamann A. and M.S. Poesch. (2023) Small-bodied fish species from western United States will be under severe water stress by 2040. Conservation Science and Practice: e12856.

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

McPherson, M.*, Lewis, J.B., Cott, P.B., Baker, L.F., Mochnacz, N.J. Swanson, H.K., and S. Poesch. (2023) Habitat use by fluvial Arctic Grayling (Thymallus arcticus) across life stages in northern mountain streams. Environmental Biology of Fishes 106: 1001-1020.

Abstract:

Northern aquatic ecosystems face increasing pressures from climate change and natural resource development.  The Arctic Grayling (Thymallus arcticus) is a widely distributed, northern freshwater fish which can be vulnerable to such pressures. There remains a paucity of information on life stage requirements through most of the species’ range to reliably map and manage habitat to protect populations into the future. We sought to characterize fluvial Arctic Grayling distribution among mountain streams and determine habitat characteristics that habitat use across life stages. Sampling was conducted at 183 sites across the Little Nahanni River watershed to collect information on fish distribution and reach-scale habitat parameters. Arctic Grayling were collected for biological analyses of age, size, weight, and reproductive development. Based on age and size-classes there were four distinct post-emergence life stages: YOY, juvenile, sub-adult and adult. YOY Arctic Grayling were found exclusively in low elevation (<1000 m) streams, flat-water habitat dominated by silty-sand substrate with average water temperatures >10oC. Similarly, juvenile Arctic Grayling occupied low elevation, warm water stream habitat, but associated strongly with run habitats. Sub-adult Arctic Grayling, the most widely distributed life-stage, were found associated with riffle, pool, and cascade-boulder habitats. Adults occupied high elevation (>1200 m) habitats that were cold (mean stream temperature = 7oC), and had higher proportions of pool and boulder habitat. The dynamic nature of Arctic Grayling habitat use in mountain streams highlights the need to consider habitat complexes at the watershed scale when defining species life stage requirements, managing habitats, monitoring populations, and assessing potential impacts. Keywords: Climate Change; Water Stress; Biodiversity; Preservation.

Citation: McPherson, M., Lewis, J.B., Cott, P.B., Baker, L.F., Mochnacz, N.J. Swanson, H.K., and S. Poesch. (2023) Habitat use by fluvial Arctic Grayling (Thymallus arcticus) across life stages in northern mountain streams. Environmental Biology of Fishes 106: 1001-1020. 

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Pandit, S.N.*, Koriala, L., Maitland, B.M*, Poesch, M.S., and E. Enders. (2017) Climate change risks, extinction debt, and conservation implications for an endangered freshwater fish Carmine Shiner (Notropis percobromus). Science of the Total Environment 598: 1-11.

*Lab members: Morag McPherson and Mark Poesch. Check out opportunities in the lab!

Medinski, N.A.*, Maitland, B.M.*, Jardine, T.D., Drake, D.A.R. and M.S. Poesch (2022) A catastrophic coal mine spill in the Athabasca River watershed induces isotopic niche shifts in stream biota including an endangered rainbow trout ecotype. Canadian Journal for Fisheries and Aquatic Sciences 79(8): 1321-1334.

Abstract:

Freshwater biodiversity is declining from impacts associated with anthropogenic stressors. Here, we use carbon (δ13C) and nitrogen (δ15N) stable isotopes to assess food web effects following a coal mine spill that displaced biota and altered biophysical stream characteristics. We compared isotopic niche metrics of benthic macroinvertebrates and the fish community, including non-native brook trout (Salvelinus fontinalis) and endangered Athabasca rainbow trout (Oncorhynchus mykiss), to infer spatial differences in site-specific resource use along a habitat disturbance gradient. Predatory benthic macroinvertebrate trophic position was elevated where impacts from the spill were most pronounced. Autochthonous carbon contribution to consumer diets was lowest in biota sampled at the most highly impacted site from the mine spill, leading to an unexpected expansion of the isotopic niche size of rainbow trout and the aquatic invertebrate community. Collectively, our results suggest spatial variation in trophic resource assimilation across multiple levels of the food web, fuelled by the allochthonous energy pathway in highly impacted study sites. We conclude this reflects a biotic response to altered basal aquatic resources following a major industrial disturbance.

Citation: Medinski, N.A., Maitland, B.M., Jardine, T.D., Drake, D.A.R. and M.S. Poesch (2022) A catastrophic coal mine spill in the Athabasca River watershed induces isotopic niche shifts in stream biota including an endangered rainbow trout ecotype. Canadian Journal for Fisheries and Aquatic Sciences 79(8): 1321-1334.

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Nelson-Chorney, H.*, Carli, C.M., Davis, C.S., Vinebrooke, R.D., Poesch, M.S., and M.K. Taylor (2019) Environmental DNA in lake sediment reveals biogeography of native genetic diversity. Frontiers in Ecology and Evolution 17: 313-318.

*Lab members: Nathan Medinski, Bryan Maitland, Mark Poesch. Check out opportunities in the lab!

Roberts, K.N.*, Lund, T.*, Hayden, B. and M.S. Poesch (2022) Season and species influence stable isotope ratios between lethally and non-lethally sampled tissues in freshwater fish. Journal of Fish Biology 100 (1): 229-241.

Abstract:

The field of stable isotope ecology is moving away from lethal sampling (internal organs and muscle) towards non-lethal sampling (fins, scales and epidermal mucus). Lethally and non-lethally sampled tissues often differ in their stable isotope ratios due to differences in metabolic turnover rate and isotopic routing. If not accounted for when using non-lethal tissues, these differences may result in inaccurate estimates of resource use and trophic position derived from stable isotopes. To address this, the authors tested whether tissue type, season and their interaction influence the carbon and nitrogen stable isotope ratios of fishes and whether estimates of species trophic position and resource use are affected by tissue type, season and their interaction. This study developed linear conversion relationships between two fin types and dorsal muscle, accounting for seasonal variation. The authors focused on three common temperate freshwater fishes: northern pike Esox lucius, yellow perch Perca flavescens and lake whitefish Coregonus clupeaformis. They found that fins were enriched in 13C and depleted in 15N compared to muscle in all three species, but the effect of season and the interaction between tissue type and season were species and isotope dependent. The estimates of littoral resource use based on fin isotope ratios were between 13% and 36% greater than those based on muscle across species. Season affected this difference for some species, suggesting the potential importance of using season-specific conversions when working with non-lethal tissues. Fin and muscle stable isotopes produced similar estimates of trophic position for northern pike and yellow perch, but fin-based estimates were 0.2–0.4 trophic positions higher than muscle-based estimates for lake whitefish. The effect of season was negligible for estimates of trophic position in all species. Strong correlations existed between fin and muscle δ13C and δ15N values for all three species; thus, linear conversion relationships were developed. The results of this study support the use of non-lethal sampling in stable isotope studies of fishes. The authors suggest that researchers use tissue conversion relationships and account for seasonal variation in these relationships when differences between non-lethal tissues and muscle,
and seasonal effects on those differences, are large relative to the scale of isotope values under investigation and/or the trophic discrimination factors under use.

Citation: Roberts, K.N., Lund, T., Hayden, B. and M.S. Poesch (2022) Season and species influence stable isotope ratios between lethally and non-lethally sampled tissues in freshwater fish. Journal of Fish Biology 100 (1): 229-241. DOI: 10.1111/jfb.14939

Finalist for FSBI Huntingford Medal. Note: One of two papers that received the “Highly Commended” designation.

Also Read:

Finn, K.*, Roberts, K.N.* and M.S. Poesch (2022) Cestode parasites are depleted in 15N relative to their fish hosts in northern Alberta, Canada. Fisheries Research 248: 106193..

*Lab members: Karling Roberts, Mark Poesch. Check out opportunities in the lab!