Category Archives: Mark Poesch

My research focuses on issues related to aquatic biodiversity, including: conservation of freshwater fishes (e.g. species at risk, invasive species), sustainable resource development and developing robust restoration and reclamation activities. My goals are to: build effective collaborations across Alberta and North America; to train the next generation of research leaders; to provide an atmosphere of respect and learning; to engage the public and stakeholders; and, to develop leading edge novel research to solve applied problems.

Maitland, B.*, Cooke, S. and M.S. Poesch. (2015) Finding the path to a successful graduate and research career: Advice for early career researchers. Fisheries 40: 399-403.

Citation: Maitland, B.*, Cooke, S. and M.S. Poesch. 2015. Finding the path to a successful graduate and research career: Advice for early career researchers. Fisheries 40: 399-403.

Abstract

The path to a successful graduate and research career is a complex and difficult one. Early career researchers (ECRs) have myriad choices and tasks to prioritize and complete as they build their CV but are often confronted with unfamiliar situations in which advice from more senior researchers can be extremely valuable. Here, we summarize a recent workshop held for ECRs by the Canadian Aquatic Resource Section of the American Fisheries Society (AFS) with support from the Education Section. Sessions touched on (1) getting published, (2) science communication and outreach, (3) scoring a job or grad school position, and (4) working within the science–policy interface. The decades of collective experience brought to the table should be shared with the broader readership of AFS because it may prove useful to ECRs as well as stimulate meaningful conversations on these important and timely issues.

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

Poesch, M.S. (2015) To dendrogram or not? Consensus methods show that the question needed to move functional diversity metrics forward. Ideas in Ecology and Evolution. 8: 70-74.

Abstract:

Functional diversity indices have become important tools for measuring variation in species characteristics that are relevant for ecosystem services. A frequently used dendrogram-based method for measuring functional diversity, ‘FD’, was shown to be sensitive to methodological choices in its calculation, and consensus methods have been suggested as an improvement. The objective of this study was to determine whether consensus methods can be used to reduce sensitivity when measuring FD. To calculate FD, a distance measure and a clustering method must be chosen. Using data from three natural communities, this study demonstrates that consensus methods were unable to resolve even simple choices of distance measure (Euclidean and cosine) and clustering method (UPGMA, complete and single linkage). Overall, there was low consensus, ranging from 41–45%, across choices inherent in functional diversity. Further, regardless of how FD was measured, or how many species were removed from the community, FD closely mirrored species richness. Future research on the impact of methodological choices, including choices inherent in producing a dendrogram and the statistical complications they produce, are needed to move functional diversity metrics forward.

Citation: Poesch, M.S. 2015. To dendrogram or not? Consensus methods show that the question needed to move functional diversity metrics forward. Ideas in Ecology and Evolution. 8: 70-74.

Also Read:

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.

Christensen-Dalsgaard, K., Sinnatamby, R.N.*, and M.S. Poesch. (2014) Metrics for assessing fisheries productivity of oil sands compensation lakes under Canada’s new Fisheries Act. Oil Sands Research and Information Network, University of Alberta, School of Energy and the Environment, Edmonton, Alberta. OSRIN Report No. TR-X. 52 pp

Summary:

The Alberta oil sands region contains one of the world’s largest oil deposits, estimated at 1.7 trillion barrels. Development in this region can have negative effects for aquatic species, governed under Canada’s Fisheries Act. The Fisheries Act allows the possibility for offsetting losses in fisheries productivity, e.g., through the creation of compensation lakes. Offsetting strategies are becoming increasingly important for large-scale developments such as mining operations in the oil sands region; they allow for development while ensuring that the project has ‘no net loss’ in fisheries productivity. In 2012, omnibus Bill C-38 fundamentally changed large sections of the federal Fisheries Act. The focus of fisheries management was shifted from the protection of fish habitat in general to ensuring the ongoing productivity (FP) of fish important to commercial, recreational and aboriginal (CRA) fisheries. Further, the changes formalized the use of offsetting strategies to compensate for damage to fish caused by development. The changes marked the move from the fisheries habitat management program (FHMP) as implemented prior to 2012, to the fisheries protection program (FPP). The goal of the FPP is to “provide for the sustainability and ongoing productivity of commercial, recreational and Aboriginal fisheries”. Lack of standardized protocols and procedures following a shift of this magnitude could not only result in considerable additional expenses for industry, but also in less reproducible and so less reliable results. Rapid standardization of best practices and data collection methods would help ensure cost-efficient, meaningful and transferable data. Currently, these best management practices are being determined through an ongoing process involving Fisheries and Oceans Canada (DFO), industrial partners and government officials. The aim is to define a standard set of indicators for use under the FPP framework and assess which models may suitable for forming the link between data sets and long-term projections for whole-population productivity. The interpretation of the changes to the Fisheries Act has been subject to controversy, making concise and publically available information important. Numerous scientific advisory reports have been published by DFO. However, there is currently a shortage of documents that give an overview over the scientific background necessary to understand how the changes may affect management practices, taking into account knowledge gaps and limitations in terms of data collection techniques. In this report, we will review existing monitoring tools as well as how the changes in policies associated with the shift from the FHMP to the FPP may affect management protocols. Under the FHMP, the conceptual endpoint for assessing the impacts of development on fisheries was to achieve no net loss of the productive capacity of fish habitat (PC). Habitat was quantified mainly by area, and the success of an offsetting project was often determined mainly through acceptable installation. Methods in use under the FHMP provided only approximate values for PC. For a meaningful planning, measurement and monitoring protocol that can help ensure fisheries productivity under the FPP, it may be necessary to move away from the previous practice of managing fish habitat in Canada based on the use of FP as a theoretical concept only. As productivity in itself is difficult to measure directly, it is necessary to find appropriate indicators that can link changes in the components of productivity of individual fish or subsections of populations to changes in population-level fisheries productivity. We have compiled a list of indicators that may be used for estimating productivity of fisheries populations. Solid measurements of fisheries productivity require repeated monitoring protocols extended over multiple years as well as a broadening of the definition of habitat affected by development. The financially and ecologically prohibitive nature of obtaining comprehensive, long-term data sets may make models an essential tool for linking limited data on subsets of populations with whole-population productivity and long-term projections. However, the trade-off between strength of model predictions and quality and quantity of data may make it a challenge to strike the balance between data needs for accurate predictions and financial feasibility. In using knowledge-based standards for planning and executing compensation lake development, a key parameter to evaluate would be the carrying capacity of various compensation lake ecosystems. It may be a challenge to ensure an appropriate agreement between offsetting indicators and environmental assessment indicators, as established ecosystems are compared with populations in the process of establishing in a newly expanded habitat. On the other hand, lack of density dependence in the early establishment phase gives good possibilities for providing solid estimates of intrinsic growth rate of the populations within this specific habitat. Future research should be conducted for areas characterized by intensive development to create models that allow for robust estimates of productivity based on limited and specific indicators that are manageable to measure. As factors limiting fisheries productivity vary between species, habitats and regions, it is likely that this would have to occur through the development of models specific for the given habitats and geographical areas. If the drivers of the ecosystem in question are not well studied, the most cost-effective and ecologically sound way of implementing the FPP may be to adopt the management practices of the FHMP largely unaltered, but with the interpretive end goal shifted to FP. This would only require a mandatory inclusion of population level data in the monitoring protocols, and an extended monitoring period of several years. All of this constitutes protocols already in use under the FHMP. Though much work has been done on measuring and modelling the productivity of fish populations, it has proven difficult or impossible to find simple, reproducible techniques that can be applied across habitat types and ecosystems. In our opinion, the best predictors for fisheries productivity remain the quantity and quality of available fish habitat combined with abundance, size structure data and species composition within the given habitats.

Citation: Christensen-Dalsgaard, K., Sinnatamby, R.N., and M.S. Poesch. (2014) Metrics for assessing fisheries productivity of oil sands compensation lakes under Canada’s new Fisheries Act. Oil Sands Research and Information Network, University of Alberta, School of Energy and the Environment, Edmonton, Alberta. OSRIN Report No. TR-X. 52 pp.

Also Read:

Theis, S.* and M. S. Poesch. (In Press).  Mitigation bank applications for freshwater systems: Control mechanisms, project complexity, and caveats. PLOS One.

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

Poesch, M.S. (2014) Developing standardized methods for sampling freshwater fishes with multiple gears: Effect of sampling order versus sampling method. Transactions of the American Fisheries Society 143: 353-362

Abstract:

Developing robust methodologies for sampling freshwater fishes is important for the assessment and recovery of aquatic biodiversity. Commonly, sampling protocols recommend the use of both electrofishing and seining to reduce bias when sampling freshwater fishes. The objective of this study was to determine whether sampling method, sampling order, or the combination of these influenced the assessment of diversity and abundance of common or rare freshwater fishes at both the species and assemblage level. Fifty sites were sampled in the Sydenham River, Ontario, Canada, where paired sites were sampled using both electrofishing and seine netting in close proximity but also reversing the initial sampling order. Differences in the abundance and richness of common and rare freshwater fishes were tested with two-way ANOVA and multivariate ANOVA. Multivariate differences in the representation of species assemblages were compared using Procrustes analysis across ordinations built using differences in sampling method and sampling order. Electrofishing outperformed seine netting for maximizing the abundance of both all species caught (P = 0.004) and only those species considered rare (P = 0.049). While capture efficiencies generally decreased with subsequent sampling, the interaction between sampling method and sampling order for maximizing richness estimates of rare species was significant (P = 0.049). There were important species and assemblage differences when sampling order was reversed. The representation of either sunfishes (family Centrarchidae) or catfishes (family Ictaluridae) differed in multivariate space, given different sampling order. In addition, the capture of Blackstripe Topminnow Fundulus notatus was enhanced when seine netting was used after electrofishing. This study highlights the often neglected aspect of choosing an appropriate sampling order when developing protocols for sampling freshwater fishes with multiple methods. Overall, the combination of electrofishing, followed by seine netting, appears to maximize capture efficiencies of both common and rare fishes; however, researchers should be aware that sampling order can alter the representation of species and assemblages in multivariate assessments.

Citation: Poesch, M.S. 2014. Developing standardized methods for sampling freshwater fishes with multiple gears: Effect of sampling order versus sampling method. Transactions of the American Fisheries Society 143: 353-362.

Also Read:

Chu, C., Holbrook, B., Sandstrom, S. and M.S. Poesch. (In Press) Cold water fish sampling in small standing waters. In Standard Methods for Sampling North American Freshwater Fishes (2nd edition), Merrcado, S. and K. Pope (eds.), American Fisheries Society, Bethesda, MY.

Boyce, M. and Poesch, M.S. 2013. Research needs for fisheries and wildlife in Alberta. 35pp., Alberta Conservation Association, Edmonton, AB.

Citation: Boyce, M. and Poesch, M.S. 2013. Research needs for fisheries and wildlife in Alberta. 35pp., Alberta Conservation Association, Edmonton, AB.

Link to report

Summary

Fisheries and wildlife management in North America is based on an extensive background of basic and applied research (Geist and McTaggart-Cowan 1995, Organ et al. 2010). Alberta has some of the finest hunting and fishing opportunities in the world with sustainably harvested populations of a diversity of fishes, birds, and mammals. However, because of aggressive industrial development, especially by the energy sector, future opportunities for hunting and fishing might be jeopardized unless habitats are managed carefully to ensure viable populations of fish and wildlife (Naugle 2011). Our objective is to identify research that is required to ensure that resource managers have the information required to make sound management decisions in the future. To obtain this list of research topics we have surveyed fisheries and wildlife biologists and managers from the Alberta Department of Environment and Sustainable Resource Development (ESRD), and the Alberta Conservation Association (ACA). We held meetings with ESRD and ACA staff in Sherwood Park, Lethbridge, and Edmonton, Alberta and also received suggestions from others throughout the province by e-mail. Subsequently we conducted literature reviews to provide background information on the published research already conducted on each topic, and we summarize briefly what we believe to be feasible and timely research.

This report is an update of the original research-needs document prepared by Boyce (2000) that was updated for wildlife research in 2005 (Boyce 2005). We have used the Simple Multi-attribute Rating Techniques (SMART) process again to rank research projects according to a process developed by Ralls and Starfield (1995), which is detailed in the Appendix. These ranks identify the most-important research according to criteria identified by ACA and ESRD fish and wildlife biologists and managers. Academic ecologists likely would identify a different list of priorities (Cristescu and Boyce 2013), and input from practicing field biologists and managers will help to ensure that research can influence policy (Neff 2011). Projects in the top third are marked ***, middle third **, and lowest-ranked projects *

Poesch, M.S. and D.A. Jackson (2012) Addressing the removal of rare species in multivariate bioassessments: the impact of methodological choices. Ecological Indicators 18: 82-90.

Abstract:

Multivariate analyses are important tools for the biological assessment of ecological communities. Despite the popularity of multivariate analyses in bioassessments, there is considerable controversy over how to treat rare species. As this debate remains unresolved, the objective of this study was to develop a methodology to quantify the impacts of removing rare species relative to other decisions inherent in multivariate analyses and to provide insight into their relative influence in our studies. Using fish species from a well-sampled system, we assessed the impact of several choices common to multivariate analyses, including the removal of rare species, ordination technique and measures of multivariate resemblance. Comparisons of multivariate analyses demonstrated the choice of ordination method explained 26% of the variation among the various results, followed by the choices regarding the removal of rare species (24.8%) and resemblance measure (11%). At the same time, the removal of rare species had important site-level impacts relative to full dataset, including a >9 fold change in sites impacted by the removal of single species, with an emphasis on removing species more correlated to anthropogenic stress. Our study demonstrates that the removal of rare species had similar or greater influence in multivariate analyses as other choices inherent in their calculation, such as the choice of ordination method. Better justifications for the removal of rare species, along with all decisions in multivariate analyses, are needed to move bioassessments forward.

Citation: Poesch, M.S. & Jackson, D.A. 2012. Addressing the removal of rare species in multivariate bioassessments: the impact of methodological choices. Ecological Indicators 18: 82-90.

Also Read:

Fischer, S.M.*, Ramaza, P., Simmons, S., Poesch, M.S. and M.A. Lewis. (2023) Boosting propagule transport models with individual-specific data from mobile apps. Journal of Applied Ecology 60(5): 934-949.

Poesch, M.S. and D.A. Jackson (2012) Impact of species-specific dispersal and regional stochasticity on estimates of population viability in stream metapopulations. Landscape Ecology 27: 405-416.

Abstract:

Species dispersal is a central component of metapopulation models. Spatially realistic metapopulation models, such as stochastic patch-occupancy models (SPOMs), quantify species dispersal using estimates of colonization potential based on inter-patch distance (distance decay model). In this study we compare the parameterization of SPOMs with dispersal and patch dynamics quantified directly from empirical data. For this purpose we monitored two metapopulations of an endangered minnow, redside dace (Clinostomus elongatus), using mark-recapture techniques across 43 patches, re-sampled across a 1 year period. More than 2,000 fish were marked with visible implant elastomer tags coded for patch location and dispersal and patch dynamics were monitored. We found that species-specific dispersal and distance decay models provided qualitatively similar rankings of viable patches; however, there were differences of several orders of magnitude in the estimated intrinsic mean times to extinction, from 24 and 148 years to 362 and >100,000 years, depending on the population. We also found that the rate of regional stochasicity had a dramatic impact for the estimate of species viability, and in one case altered the trajectory of our metapopulation from viable to non-viable. The divergent estimates in time to extinction times were likely due to a combination species-specific behavior, the dendritic nature of stream metapopulations, and the rate of regional stochasticity. We demonstrate the importance of developing comparative analyses using species- and patch-specific data when determining quantitative estimates for mean time to extinction, which in the case of redside dace, were highly sensitive to different estimates of dispersal.

Citation: Poesch, M.S. & Jackson, D.A. 2012. Impact of species-specific dispersal and regional stochasticity on estimates of population viability in stream metapopulations. Landscape Ecology 27: 405-416.

Also Read:

Neufeld, K.*, Watkinson, D., Tierney, K. and M.S. Poesch. (2018) Incorporating connectivity in measures of habitat suitability to assess impacts of hydrologic alteration to stream fish. Diversity and Distributions 24: 593-604.