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..

Abstract:

The use of stable isotopes to study trophic interactions and food webs has become a common practice in ecology. Until recently, parasites were largely omitted from these analyses despite their known contribution to ecosystem complexity and function. Long-standing assumptions about the enrichment of δ15N in consumers relative to their resources occasionally placed parasites in trophic positions above their hosts. However, recent literature has shown that unlike consumers to prey, parasites do not reliably exhibit enrichment in δ15N. This is particularly true of helminth endoparasites in the class cestoda, which tend to be depleted in δ15N. We developed empirical estimates of nitrogen and carbon stable isotope ratios from a cestode parasite (Ligula intestinalis) across four fish hosts from two lakes in northern Alberta, Canada. We found that L. intestinalis were depleted in δ15N relative to their hosts across all host fish species, with mean nitrogen discrimination factors (Δ15N) ranging from -1.92 ± 0.24 ‰ to -2.91 ± 1.17 ‰. In contrast, δ 13C values did not differ significantly in any direction between hosts and their parasites. Mean carbon discrimination factors (Δ13C) ranged from -0.66 ± 2.69 ‰ to 0.04 ± 1.53 ‰. We also tested for relationships between proportional parasite biomass and discrimination factor (Δ15N & Δ13C), and found high variability in strength and direction of these correlations across species. The direction and magnitude of nitrogen discrimination we found for L. intestinalis is similar to that of previous cestode stable isotope studies and may indicate consistency across the class cestoda. However, class cestoda is incredibly diverse and relatively few studies have examined host-parasite
discrimination factors within the clade. We encourage additional research into host-parasite discrimination factors for the class cestoda, and across all parasite taxa. This could facilitate the inclusion of these widespread interactions into food web studies, thus improving our knowledge of trophic structure and dynamics.

Citation: 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.

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

Pereyra, P.E.R, Hallwas, G., Poesch, M.S. and R. Silvano (2021) ‘Taking fishers’ knowledge to the lab’: an interdisciplinary approach to understand fish trophic relationships in the Brazilian Amazon. Frontiers in Ecology and Evolution 9: 723026.

Abstract:

Trophic levels can be applied to describe the ecological role of organisms in food webs and assess changes in ecosystems. Stable isotopes analysis can assist in the understanding of trophic interactions and use of food resources by aquatic organisms. The local ecological knowledge (LEK) of fishers can be an alternative to advance understanding about fish trophic interactions and to construct aquatic food webs, especially in regions lacking research capacity. The objectives of this study are: to calculate the trophic levels of six fish species important to fishing by combining data from stable isotopes analysis and fishers’ LEK in two clear water rivers (Tapajós and Tocantins) in the Brazilian Amazon; to compare the trophic levels of these fish between the two methods (stable isotopes analysis and LEK) and the two rivers; and to develop diagrams representing the trophic webs of the main fish prey and predators based on fisher’s LEK. The fish species studied were Pescada (Plagioscion squamosissimus), Tucunaré (Cichla pinima), Piranha (Serrasalmus rhombeus), Aracu (Leporinus fasciatus), Charuto (Hemiodus unimaculatus) and Jaraqui (Semaprochilodus spp.). A total of 98 interviews and 63 samples for stable isotopes analysis were carried out in both rivers. The average fish trophic levels did not differ between the stable isotopes analysis and the LEK in the Tapajós, nor in the Tocantins Rivers. The overall trophic level of the studied fish species obtained through the LEK did not differ from data obtained through the stable isotopes analysis in both rivers, except for the Aracu in the Tapajós River. The main food items consumed by the fish according to fishers’ LEK did agree with fish diets as described in the biological literature. Fishers provided useful information on fish predators and feeding habits of endangered species, such as river dolphin and river otter. Collaboration with fishers through LEK studies can be a viable approach to produce reliable data on fish trophic ecology to improve fisheries management and species conservation in tropical freshwater environments and other regions with data limitations.

Citation: Pereyra, P.E.R, Hallwas, G., Poesch, M.S. and R. Silvano (2021) ‘Taking fishers’ knowledge to the lab’: an interdisciplinary approach to understand fish trophic relationships in the Brazilian Amazon. Frontiers in Ecology and Evolution 9: 723026.

Also Read:

Dutra, M.C.F., Pereyra, P.E.R., Hallwass, G., Poesch, M.S. and R.A.M. Silvano. (2023). Fishers’ knowledge on trophic ecology and of the tropical ‘super fish’ Plagioscion squamosissimus in two Brazilian Amazonian rivers. Neotropical Ichthyology 21(1): e220041.

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

Castaneda, R.A., Ackerman, J.D., Chapman, L.J., Cooke, S.J., Cuddington, K., Dextrase, A., Jackson, D.A., Koops, M.A., Krkosek, M., Loftus, K., Mandrak, N.E., Martel, A.L., Molnar, P., Morris, T.J., Pitcher, T.E., Poesch, M.S., Power, M., Pratt, T.C., Reid, S.M., Rodriguez, M.A., Rosenfeld, J., Wilson, C., Zanatta, D.T. and D.A.R. Drake. (2021) Approaches and research needs for advancing the protection and recovery of imperilled freshwater fishes and mussels in Canada. Canadian Journal of Fisheries and Aquatic Sciences 78 (9): 1356-1370.

Abstract:

Effective conservation requires that species recovery measures are informed by rigorous scientific research. For imperilled freshwater fishes and mussels in Canada, numerous research gaps exist, in part owing to the need for specialized research methods. The Canadian Freshwater Species at Risk Research Network (SARNET) was formed, and identified or implemented approaches to address current research gaps, including: 1) captive experimental research populations; 2) non-lethal methods for estimating abundance and distribution; 3) non-lethal field methods to measure life-history parameters; 4) species distribution models informed by co-occurring species; 5) integration of conservation physiology into habitat and threat science; 6) evidence syntheses to evaluate threats and recovery strategies; 7) disease-transmission models to understand mussel-host relationships; 8) experimental mesocosms and manipulative experiments to evaluate key habitat stressors; 9) threat and hazard models for predictive applications; and, 10) rigorous evaluation of surrogate species. Over a dozen threat and recovery-focused SARNET-research applications are summarized, demonstrating the value of a coordinated research program between academics and government to advance scientific research on, and to support the recovery of, imperilled freshwater species.

Citation: Castaneda, R.A., Ackerman, J.D., Chapman, L.J., Cooke, S.J., Cuddington, K., Dextrase, A., Jackson, D.A., Koops, M.A., Krkosek, M., Loftus, K., Mandrak, N.E., Martel, A.L., Molnar, P., Morris, T.J., Pitcher, T.E., Poesch, M.S., Power, M., Pratt, T.C., Reid, S.M., Rodriguez, M.A., Rosenfeld, J., Wilson, C., Zanatta, D.T. and D.A.R. Drake. (2021) Approaches and research needs for advancing the protection and recovery of imperilled freshwater fishes and mussels in Canada. Canadian Journal of Fisheries and Aquatic Sciences 78 (9): 1356-1370.

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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!

Baird, I., Silvano, R., Parlee, B., Poesch, M., Napolean, A., Lepine, M., Halwass, G., and B. MacLean. (2021) The Downstream Impacts of Hydropower Dams and Indigenous and Local Knowledge: Examples from the Peace-Athabasca, Mekong and Amazon River Basins. Environmental Management 67: 682-696.

Abstract:

There has been much written about the negative social and environmental impacts of large hydropower dams, particularly the impacts on people and the environment caused by flooding linked to the creation of large reservoirs. There has also long been recognition of the importance of Indigenous and local knowledge for understanding ecological processes and environmental impacts. In this paper, however, we focus on a topic that has received insufficient consideration: the downstream impacts of dams, and the role of Indigenous and local knowledge in assessing and addressing these impacts. Using examples from three river basins in different parts of the world: the Peace-Athabasca in Canada, the Mekong in mainland Southeast Asia, and the Amazon in Brazil, we demonstrate that the downstream impacts of hydropower dams are often neglected due to the frequently long distances between dams and impacted areas, jurisdictional boundaries, and the less obvious nature of downstream impacts. We contend that Indigenous or local knowledge, if applied consistently and appropriately, have important roles to play in understanding and addressing these impacts, with the goal of avoiding, reducing, and appropriately compensating for the types of environmental injustices that are frequently associated with the downstream impacts of dams.

Citation: Baird, I., Silvano, R., Parlee, B., Poesch, M., Napolean, A., Lepine, M., Halwass, G., and B. MacLean. (2021) The Downstream Impacts of Hydropower Dams and Indigenous and Local Knowledge: Examples from the Peace-Athabasca, Mekong and Amazon River Basins. Environmental Management 67: 682-696

Link to Article

Also Read:

Pereyra, P.E.R, Hallwas, G., Poesch, M.S. and R. Silvano (2021) ‘Taking fishers’ knowledge to the lab’: an interdisciplinary approach to understand fish trophic relationships in the Brazilian Amazon. Frontiers in Ecology and Evolution.

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

Banting, A.*, Vinebrooke, R., Taylor, M., Carli, C. and M.S. Poesch. (2021) Impacts of a regionally-native predator on littoral macrobenthos in fishless mountain lakes: implications for assisted colonization. Conservation Science and Practice 3(2): e344.

Abstract:

The intentional introduction of native cold-water trout into high elevation fishless lakes has been considered as a tool for building resilience to climate change (i.e. “assisted colonization”). However, ecological impacts on recipient communities are understudied. Our purpose was to inform native trout recovery by assessing potential consequences of translocating a regionally-native trout (Westslope Cutthroat Trout, Oncorhynchus clarkii) into fishless mountain lakes. We compared littoral benthic invertebrate richness, diversity, community structure, and density between three groups of lakes (native trout, nonnative trout, and fishless) in the Canadian Rocky Mountains. While richness and diversity was conserved across all lake groups, other lines of evidence suggested introducing native Westslope Cutthroat Trout into fishless lakes can alter littoral benthic invertebrate communities in similar ways as nonnative Brook Trout (Salvelinus fontinalis). The community structure of Cutthroat Trout lakes resembled Brook Trout lakes in comparison to fishless lakes. For example, both trout lake groups contained lower density of free-swimming ameletid mayflies and a higher density of some burrowing taxa. Considering the alteration certain aquatic invertebrates can cause cascading trophic effects, we suggest risk assessments consider a broad range of taxa to mitigate risk of collateral damage from trout recovery actions.

Citation: Banting, A., Vinebrooke, R., Taylor, M., Carli, C. and M.S. Poesch. (2021) Impacts of a regionally-native predator on littoral macrobenthos in fishless mountain lakes: implications for assisted colonization. Conservation Science and Practice 3(2): e344.

Also Read:

Castaneda, R.A., Ackerman, J.D., Chapman, L.J., Cooke, S.J., Cuddington, K., Dextrase, A., Jackson, D.A., Koops, M.A., Krkosek, M., Loftus, K., Mandrak, N.E., Martel, A.L., Molnar, P., Morris, T.J., Pitcher, T.E., Poesch, M.S., Power, M., Pratt, T.C., Reid, S.M., Rodriguez, M.A., Rosenfeld, J., Wilson, C., Zanatta, D.T. and D.A.R. Drake. (2021) Approaches and research needs for advancing the protection and recovery of imperilled freshwater fishes and mussels in Canada. Canadian Journal of Fisheries and Aquatic Sciences 78 (9): 1356-1370.

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

Donadt, C.*, Cooke, C., Graydon, J. and M.S. Poesch. (2021) Biological factors moderate trace element accumulation in fish along an environmental concentration gradient. Environmental Toxicology and Chemistry 40(2): 422-434.

Abstract:

Trace elements can accumulate in aquatic foodwebs, becoming potentially hazardous wildlife and human health. While many studies have examined mercury dynamics in freshwater environments, evidence for the bioaccumulative potential of other trace elements (e.g., arsenic) is conflicting. Trace element concentrations found in surface water of the Red Deer River, Alberta, Canada, have raised concern for potential accumulation in aquatic biota. We investigated fish from this river to better understand the influence of biological and environmental factors in trace element bioaccumulation. We analyzed 20 trace elements and food web tracers, stable nitrogen (δ¹⁵N) and carbon (δ¹³C) isotopes, in muscle tissue. Zinc, selenium, arsenic, chromium, and nickel were detected in the majority of fish at low concentrations. However, mercury was detected in all fish and often exceeded criteria for the protection of consumers. Body size was often positively correlated with trace element concentrations. Additionally, food web tracers were correlated to mercury and arsenic concentrations, indicating that mercury biomagnifies whereas arsenic bio-diminishes. Spatial patterns of fish trace element concentrations did not reflect differences in surface water concentrations. These findings indicate that fish trace element concentrations are primarily moderated by biological factors, such as trophic position and body size, and are not locally restricted to areas of relatively high environmental concentrations in the Red Deer River.

Citation: Donadt, C., Cooke, C., Graydon, J. and M.S. Poesch. (2021) Biological factors moderate trace element accumulation in fish along an environmental concentration gradient. Environmental Toxicology and Chemistry 40(2): 422-434.

Also Read:

Ponton D.E., Ruelas-Inzunza J., Lavoie R., Lescord G.L., Johnston T.A., Graydon J.A., Reichert, M., Donadt C.*, Poesch M.S., Gunn, J.A., and M. Amyot. (2022) Mercury, selenium and arsenic concentrations in Canadian freshwater fish and a perspective on human consumption intake and risk. Journal of Hazardous Materials Advances.

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

Donadt, C.*, Cooke, C., Graydon, J. and M.S. Poesch. (2021) Mercury bioaccumulation in stream fish from an agriculturally-dominated watershed. Chemosphere 262: 128059.

Abstract:

Bioaccumulation of mercury in freshwater fish is a complex process driven by environmental and biological factors. In this study, we assessed mercury in fish from four tributaries to the Red Deer River, Alberta, Canada, which are characterized by high surface water mercury concentrations. We used carbon (δ13C) and nitrogen (δ15N) stable isotopes to examine relationships between fish total mercury (THg) concentrations, food web dynamics and patterns in unfiltered THg and methylmercury (MeHg) concentrations. We found that THg concentrations exceeded the tissue residue quality guideline for the protection of wildlife consumers in 99.7% of fish sampled. However, while the surface water THg concentration was highest in Michichi Creek and the MeHg concentration was consistent across streams, patterns of fish THg concentrations varied depending on species. Furthermore, body size and trophic level were only correlated with THg concentrations in white sucker (Catostomus commersoni) and Prussian carp (Carrasius gibelio). The results of this study suggest that mercury poses a risk to the health of piscivorous wildlife in the Red Deer River watershed. Despite high THg concentrations in these streams, mercury bioaccumulation is not driven by environmental inorganic mercury concentrations. Additionally, commonly cited factors associated with mercury concentrations in fish, such as body size and trophic level, may not strongly influence bioaccumulation in these stream ecosystems.

Citation: Donadt, C., Cooke, C., Graydon, J. and M.S. Poesch. (2021) Mercury bioaccumulation in stream fish from an agriculturally-dominated watershed. Chemosphere 262: 128059.

Also Read:

Donadt, C.*, Cooke, C., Graydon, J. and M.S. Poesch. (2021) Biological factors moderate trace element accumulation in fish along an environmental concentration gradient. Environmental Toxicology and Chemistry 40(2): 422-434.

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

Firth, B., Poesch, M.S., Koops, M., Power, M. and D.A.R. Drake. (2021) Diet overlap of common and at-risk riverine benthic fishes before and after Round Goby (Neogobius melanostomus) invasion. Biological Invasions 23(1): 1-14.

Abstract:

Round Goby (Neogobius melanostomus) has invaded high diversity tributaries of the Laurentian Great Lakes, including those supporting multiple species of conservation concern. The extent and magnitude of ecological impacts on benthic riverine fishes is poorly understood, especially changes in dietary overlap and feeding strategy. We used a before-after study design to examine the impact of Round Goby on native benthic riverine fishes, including the Threatened Eastern Sand Darter (Ammocrypta pellucida) in the Sydenham River, Ontario, Canada. To evaluate shifts in diet overlap and feeding strategy, fishes were collected with multiple gears and the direct (diet overlap with the invader) and potential indirect (diet overlap among the native benthic fishes) impacts of Round Goby were assessed. Before the arrival of Round Goby, there were a total of 6 ecologically significant diet overlaps among the studied native benthic fishes. Following the arrival of Round Goby, there were 20 ecologically significant diet overlaps, with 6 out of 8 species, including Eastern Sand Darter, showing significant diet overlap with Round Goby. Fishes exhibiting significant dietary overlap with Round Goby shifted feeding strategies to become more specialized, a change in feeding consistent with potential competitive effects. Although the long-term consequences of invasion-induced dietary and feeding shifts remain poorly understood, increased competitive interactions suggested by dietary overlap may be occurring between Round Goby and native benthic riverine fishes and may exacerbate the observed declines of native species.

Citation: Firth, B., Poesch, M.S., Koops, M., Power, M. and D.A.R. Drake. (2021) Diet overlap of common and at-risk riverine benthic fishes before and after Round Goby (Neogobius melanostomus) invasion. Biological Invasions 23(1): 1-14.

Also Read:

Poesch, M.S., Dextrase, A.J., Schwalb, A.N., and J. Ackerman (2010) Secondary invasion of the round goby into high diversity Great Lakes tributaries and species at risk hotspots: Potential new concerns for endangered freshwater species. Biological Invasions 12: 1269-1284.

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.

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.

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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.

*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.

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.

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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.

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Theis, S.* Koops, M. and M.S. Poesch. (2022) A meta-analysis on the effectiveness of offsetting strategies for harm to freshwater fishes. Environmental Management 70(5): 793-807.

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