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Dr. Jim Junker

Research Assistant Professor

University of North Texas

Department of Biological Sciences

(940) 369-5077

Email: James.Junker@unt.edu

Professional Positions

    Academic - Post-Secondary

  • Postdoctoral Researcher, Michigan Technological University. Michigan Technological University. (2021 - 2023).

Professional Memberships

  • Society for Freshwater Science. (January 1, 2024 - Present).
  • Ecological Society of America. (January 1, 2022 - Present).

Development Activities

  • Workshop, Fall Faculty Grantsmanship Workshop, UNT Division of Research and Innovation. Denton,Texas,United States of America. (December 10, 2024).

Research

Published Intellectual Contributions

    Book Chapter

  • O'Gorman, E.J., Pichler, D.E., Adams, G., Benstead, J.P., Cohen, H., Craig, N., Cross, W.F., Demars, Beno\^it O.L., Friberg, N., G\'islason, G\'isli M\'ar, Gudmundsd\'ottir, Rakel, Hawczak, A., Hood, J.M., Hudson, L.N., Johansson, L., Johansson, M.P., Junker, J., Laurila, A., Manson, J.R., Mavromati, E., Nelson, D., \'Olafsson, J\'on S., Perkins, D.M., Petchey, O.L., Plebani, M., Reuman, D.C., Rall, Bj\"orn C., Stewart, R., Thompson, M.S., Woodward, G. (2012). Impacts of Warming on the Structure and Functioning of Aquatic Communities. Advances in Ecological Research. 47 81--176. Elsevier.

    • Conference Proceeding

  • Demars, B., McGovern, M., Jackson-Blake, L., Sample, J., Norling, M., Høgda, K., Karlsen, S., Dörsch, P., Stutter, M., Thornton, B., Junker, J., D'Andrilli, J. (2024). QUANTOM: QUANTification of dissolved Organic Matter and the metabolic balance in river networks: mechanisms and model simulations of CO2 emissions. Copernicus GmbH. https://doi.org/10.5194/egusphere-egu24-20681

    • Journal Article

  • Novak, B., Murry, B.A., Wesner, J.S., Gjoni, V., Arantes, C.C., Shepta, E., Pomeranz, J.P., Junker, J., Zipfel, K., Stump, A., Solomon, L.E., Maxson, K.A., DeBoer, J.A. (2024). Threshold responses of freshwater fish community size spectra to invasive species. Ecosphere. 15 (12) Wiley. https://doi.org/10.1002/ecs2.70090
  • Glassic, H.C., Junker, J., Guy, C.S., Tronstad, L.M., Briggs, M.A., Albertson, L.K., Lujan, D.R., Brenden, T.O., Walsworth, T.E., Koel, T.M. (2024). An Invasive Predator Substantially Alters Energy Flux Without Changing Food Web Functional State or Stability. Other. 34 (9) Wiley. https://doi.org/10.1002/aqc.4240
  • Junker, J., Cross, W.F., Hood, J.M., Benstead, J.P., Huryn, A.D., Nelson, D., Ólafsson, J.S., Gíslason, G.M. (2024). Environmental warming increases the importance of high‐turnover energy channels in stream food webs. Ecology. 105 (6) Wiley. https://doi.org/10.1002/ecy.4314
  • Wesner, J.S., Pomeranz, J.P., Junker, J., Gjoni, V. (2024). Bayesian hierarchical modelling of size spectra. Other. 15 (5) 856-867. Wiley. https://doi.org/10.1111/2041-210x.14312
  • Pomeranz, J., Junker, J., Gjoni, V., Wesner, J.S. (2024). Maximum Likelihood Outperforms Binning Methods for Detecting Differences in Abundance Size Spectra across Environmental Gradients. Other. 93 (3) 267--280.
  • Keppeler, F.W., Junker, J., Shaw, M.J., Alford, S.B., Engel, A.S., Hooper-B\`ui, Linda M., Jensen, O.P., Lamb, K., L\'opez-Duarte, Paola C., Martin, C.W., McDonald, A.M., Olin, J.A., Paterson, A.T., Polito, M.J., Rabalais, N.N., Roberts, B.J., Rossi, R.E., Swenson, E.M. (2023). Can Biodiversity of Preexisting and Created Salt Marshes Match across Scales? An Assessment from Microbes to Predators. Ecosphere. 14 (3) e4461.
  • Scholl, E.A., Cross, W.F., Guy, C.S., Dutton, A.J., Junker, J.R. (2023). Landscape diversity promotes stable food‐web architectures in large rivers. Ecology Letters. https://doi.org/10.1111/ele.14289
  • Reinert, J.H., Albertson, L.K., Junker, J. (2022). Influence of Biomimicry Structures on Ecosystem Function in a Rocky Mountain Incised Stream. Ecosphere. 13 (1) e3897.
  • Pomeranz, J.P., Junker, J., Wesner, J.S. (2022). Individual Size Distributions across North American Streams Vary with Local Temperature. Global Change Biology. 28 (3) 848--858.
  • Junker, J., Cross, W.F., Benstead, J.P., Huryn, A.D., Hood, J.M., Nelson, D., G\'islason, G\'isli M., \'Olafsson, J\'on S. (2021). Flow Is More Important than Temperature in Driving Patterns of Organic Matter Storage and Stoichiometry in Stream Ecosystems. Ecosystems. 24 (6) 1317--1331.
  • Junker, J., Cross, W.F., Benstead, J.P., Huryn, A.D., Hood, J.M., Nelson, D., Gíslason, G.M., Ólafsson, J.S., Ghalambor, C. (2020). Resource supply governs the apparent temperature dependence of animal production in stream ecosystems. Ecology Letters. 23 (12) 1809-1819. Wiley. https://doi.org/10.1111/ele.13608
  • Nelson, D., Benstead, J.P., Huryn, A.D., Cross, W.F., Hood, J.M., Johnson, P.W., Junker, J., G\'islason, G\'isli M., \'Olafsson, J\'on S. (2020). Contrasting Responses of Black Fly Species (Diptera: Simuliidae) to Experimental Whole-Stream Warming. Freshwater Biology. 65 (10) 1793--1805.
  • Nelson, D., Benstead, J.P., Huryn, A.D., Cross, W.F., Hood, J.M., Johnson, P.W., Junker, J., G\'islason, G\'isli M., \'Olafsson, J\'on S. (2020). Thermal Niche Diversity and Trophic Redundancy Drive Neutral Effects of Warming on Energy Flux through a Stream Food Web. Ecology.
  • D'Andrilli, J., Junker, J., Smith, H.J., Scholl, E.A., Foreman, C.M. (2019). DOM Composition Alters Ecosystem Function during Microbial Processing of Isolated Sources. Other. 142 (2) 281--298.
  • Hood, J.M., Benstead, J.P., Cross, W.F., Huryn, A.D., Johnson, P.W., G\'islason, G\'isli M., Junker, J., Nelson, D., \'Olafsson, J\'on S., Tran, C. (2018). Increased Resource Use Efficiency Amplifies Positive Response of Aquatic Primary Production to Experimental Warming. Global Change Biology. 24 (3) 1069--1084.
  • Nelson, D., Benstead, J.P., Huryn, A.D., Cross, W.F., Hood, J.M., Johnson, P.W., Junker, J., Gíslason, G.M., Ólafsson, J.S. (2017). Experimental whole‐stream warming alters community size structure. Global Change Biology. 23 (7) 2618-2628. Wiley. https://doi.org/10.1111/gcb.13574
  • Nelson, D., Benstead, J.P., Huryn, A.D., Cross, W.F., Hood, J.M., Johnson, P.W., Junker, J., Gíslason, G.M., Ólafsson, J.S. (2017). Shifts in community size structure drive temperature invariance of secondary production in a stream‐warming experiment. Ecology. 98 (7) 1797-1806. Wiley. https://doi.org/10.1002/ecy.1857
  • Junker, J., Cross, W.F. (2014). Seasonality in the Trophic Basis of a Temperate Stream Invertebrate Assemblage: Importance of Temperature and Food Quality. Association for the Sciences of Limnology and Oceanography. 59 (2) 507--518.

Presentations Given

    Invited Talk

  • Junker, J.R. (Author & Presenter), College of Agriculture and Natural Resources, The influence of temperature on energy flow, food web dynamics, and community assembly in streams, Tarleton State University, Stevenville, TX, United States of America. (2024 - 2024).
  • Junker, J.R. (Author & Presenter), Department of Biological Sciences, The influence of temperature on energy flow, food web dynamics, and community assembly in streams, University of South Dakota, Vermillion, SD, United States of America. (2024 - 2024).
  • Junker, J.R. (Author & Presenter), Department of Biological Sciences, The effects of temperature on energy flow in streams from individuals to ecosystems, University of North Texas, Denton, TX, United States of America. (2024).
  • Junker, J. (Author & Presenter), Department of Biological Sciences, The effects of temperature on energy flow in streams from individuals to ecosystems, University of North Texas, Denton, TX, United States of America. (2023).
  • Junker, J.R. (Author & Presenter), Department of Biological Sciences, The effects of temperature on energy flow in streams from individuals to ecosystems., Minnesota State University, Mankato, MN, United States of America. (2023).

    • Lecture

  • Junker, J.R. (Author & Presenter), Department of Biological Sciences, Energy flow in benthic communities, University of North Texas, Denton, TX, United States of America. (2023).

    • Oral Presentation

  • D'Andrilli, J. (Author & Presenter), Junker, J. (Author & Presenter), Silverman, V. (Author), Goranov, A.I. (Author), Hatcher, P.G. (Author), Demars, B. (Author), QUANTOM River Tana Project Meeting, Understanding DOM molecular transformations in metabolic chambers, Norwegian Institute for Water Research, Oslo, Norway. (2024 - 2024).
  • D'Andrilli, J. (Author & Presenter), Silverman, V. (Author), Goranov, A.I. (Author), Hatcher, P.G. (Author), Junker, J. (Author), Demars, B. (Author), QUANTOM River Tana Project Meeting, Biogeochemical interpretations of dissolved organic matter by FT-ICR MS: DOM molecular fingerprinting, chemical characterization, and lability analysis, Norwegian Institute for Water Reserach, Oslo, Norway. (2024 - 2024).
  • Compson, Z.G. (Author & Presenter), Bucher, M. (Author), Gollapudi, M. (Author), Peters, M. (Author), MacKinnon, R. (Author), Poirier, T. (Author), Cave, K. (Author), Junker, J. (Author), Philips, E. (Author), Ihemeremadu, W. (Author), Malish, M. (Author), Cook, S. (Author), Neeson, T. (Author), Allen, D.C. (Author), Society for Freshwater Science, Using trait-based models to test food web theory at a continental scale, Philadelphia, PA, United States of America. (2024 - 2024).
  • Demars, B. (Author & Presenter), McGovern, M. (Author), Jackson-Blake, L. (Author), Sample, J. (Author), Norline, M. (Author), Hogda, K. (Author), Karlsen, S. (Author), Dorsch, P. (Author), Stutter, M. (Author), Thornton, B. (Author), Junker, J. (Author), D'Andrilli, J. (Author), European Geosciences Union, QUANTOM – QUANTification of dissolved Organic Matter and the metabolic balance in river networks: mechanisms and model simulations of CO2 emissions, Vienna, Austria. (2024 - 2024).
  • Heines, R.R. (Author & Presenter), Junker, J. (Author), Lopez-Duarte, P.C. (Author), Polito, M.J. (Author), Roberts, B.J. (Author), Olin, J.A. (Author), Gulf Estuarine Research Society Bi-annual meeting, Resource partitioning among sympatric speceis across saltmarsh ponds of coastal Louisiana, Gulf Estuarine Research Society, Ocean Spring, MS, United States of America. (2023).
  • Wesner, J.S. (Author & Presenter), Pomeranz, J. (Author), Gjoni, V. (Author), Junker, J.R. (Author), SEB Annual meeting, Responses of individual size distributions across a continental gradient of temperature and resource supply, Society for Experimental Biology, Edinburgh, Scotland, United Kingdom. (2023).
  • Junker, J.R. (Author & Presenter), Lopez-Duarte, P.C. (Author), Martin, C.W. (Author), Roberts, B.J. (Author), Jensen, O.P. (Author), Polito, M.J. (Author), Swenson, E. (Author), Olin, J.A. (Author), Gulf Estuarine Research Society Bi-annual meeting, Species- and community-level drivers of spatiotemporal variation in nekton biomass of saltmarsh ponds, Gulf Estuarine Research Society, Ocean Spring, MS, United States of America. (2022).
  • Junker, J.R. (Author & Presenter), Lopez-Duarte, P.C. (Author), Keppeler, F.W. (Author), Martin, C.W. (Author), Jensen, O.P. (Author), Fodrie, F.J. (Author), Roberts, B.J. (Author), Able, K. (Author), Polito, M.J. (Author), Turner, R.E. (Author), Olin, J.A. (Author), Joint Aquatic Science Meeting, Energy channel specificity and trophic complementarity in a saltmarsh meta-food web, Society for Freshwater Science, Grand Rapids, MI, United States of America. (2022).
  • Olin, J.A. (Author), Matich, P. (Author), Junker, J.R. (Author & Presenter), Bergeron Burns, C. (Author), Woltmann, S. (Author), Bonisoli-Alquati, A. (Author), Taylor, S. (Author), Stouffer, P. (Author), Turner, R.E. (Author), Shipley, O. (Author), Gulf of Mexico Conference, Condition consequences of niche variation in an avian consumer, Gulf of Mexico Alliance, Baton Rouge, LA, United States of America. (2022).
  • Junker, J.R. (Author & Presenter), Lopez-Duarte, P.C. (Author), Keppeler, F.W. (Author), Martin, C.W. (Author), Jensen, O.P. (Author), Fodrie, F.J. (Author), Roberts, B.J. (Author), Able, K. (Author), Polito, M.J. (Author), Turner, R.E. (Author), Olin, J.A. (Author), Gulf of Mexico Conference, Energy channel specificity and trophic complementarity in a saltmarsh meta-food web, Gulf of Mexico Alliance, Baton Rouge, LA, United States of America. (2022).

    • Poster

  • Alcantar, C. (Author & Presenter), Bucher, M. (Author), Compson, Z.G. (Author), Hoeinghaus, D.J. (Author), Junker, J. (Author), Bohenek, J. (Author), Marks, J. (Author), Cui, X. (Author), Chowdhury, F. (Author), AERI Research Day, Influence of Leaf Litter on Decomposition, Macroinvertebrate Communities, and Nutrient Transfer in Freshwater Ecosystems, University of North Texas, Sulphur, OK, United States of America. (2024 - 2024).
  • Coronado, E.A. (Author & Presenter), Deckard, G. (Author), Graffam, C. (Author), Montenegro, A. (Author), Renfrow, J. (Author), Junker, J.R. (Author), Compson, Z.G. (Author), D'Andrilli, J. (Author), Bohenek, J. (Author), AERI Research Day, Leaf litter decomposition drives ‘hot moments’ and mosquito activity in freshwater ecosystems, AERI and UNT, Sulphur, Oklahoma, United States of America. (2024 - 2024).
  • Alcantar, C. (Author & Presenter), Bucher, M. (Author), Marks, J. (Author), Hoeinghaus, D.J. (Author), Bohenek, J. (Author), Junker, J. (Author), Compson, Z.G. (Author), UNT Research Day, Leaf Litter and Macroinvertebrate Dynamics: Stable Isotope Analysis and Freshwater Ecosystems, University of North Texas, Denton, TX, United States of America. (2024 - 2024).
  • Gjoni, V. (Author & Presenter), Pomeranz, J.P. (Author), Junker, J.R. (Author), Wesner, J.S. (Author), NSF Macrosystems Biology Community Virtual Meeting, Size Spectra in freshwater streams are consistent across temperature and resource supply, National Science Foundation, Virtual, United States of America. (2024 - 2024).
  • Wesner, J.S. (Author & Presenter), Pomeranz, J. (Author), Junker, J. (Author), Joint Aquatic Sciences Meeting, The influence of temperature and resource supply on stream size spectra, Society for Freshwater Science, Grand Rapids, MI, United States of America. (2022).

Contracts, Grants, Sponsored Research

    Grant - Research

  • Bohenek, J., D'Andrilli, J., Junker, J., Compson, Z.G., "Leaf litter decomposition drives ‘hot moments’ and mosquito activity in freshwater ecosystems," sponsored by Advanced Environmental Research Institute, University of North Texas, $10000 Funded. (2024 - 2025).
  • Frisk, M.G. (Principal), Cerrato, R.M. (Co-Principal), Shipley, O.N. (Co-Principal), Junker, J.R. (Co-Principal), Olin, J.A. (Co-Principal), "Defining foraging hotspots of finfish and sharks in the New York Bight: linking trophic dynamics with spatiotemporal trends in species distributions," sponsored by NYSDEC/NYSG, State, $279357 Funded. (2024 - 2025).
  • Junker, J.R. (Principal), Compson, Z.G. (Co-Principal), Cui, X. (Co-Principal), "“AutoTaxonomizer”: Developing taxonomic- and morphology-informed neural networks for the analysis and identification of novel macroinvertebrate communities," sponsored by UNT College of Science/UNT College of Engineering, University of North Texas, $10000 Funded. (2024 - 2025).
  • Junker, J.R. (Co-Principal), "Collaborative Research: MSA: The influence of temperature and resource supply on community size spectra in streams," sponsored by National Science Foundation, Federal, $39585 Funded. (2021 - 2024).
  • Paterson, G. (Principal), Vick-Majors, T.J. (Co-Principal), Olin, J.A. (Co-Principal), Junker, J. (Co-Principal), "A novel method for quantifying Dreissenid veliger contributions to Lake Huron zooplankton communities," sponsored by Michigan SeaGrant, State, $199660 Funded. (2022 - 2024).

Service

University Service

  • Committee Member, Christopher Graffam. (March 1, 2024 - Present).
  • Committee Member, Julia Renfrow. (March 1, 2024 - Present).
  • Committee Member, Hunter Roose. (January 1, 2022 - Present).
  • Committee Member, Ryan Heines. (January 1, 2022 - July 29, 2024).

Professional Service

  • Committee Member, Society for Freshwater Science. Logan, UT. (January 1, 2024 - Present).
  • Reviewer, Ad Hoc Reviewer, Scientific Journals. (January 1, 2024 - December 31, 2024).