We are recruiting postdoc and PhD student positions for an NSF-funded project on the patterns and mechanisms of ecosystem size spectra across macroecological gradients. The anticipated start date would be in Spring/Summer 2026. Formal announcements are forthcoming, but if you are interested contact:
James Junker james.junker[at]unt.edu for the PhD student position
Jeff Wesner jeff.wesner[at]usd.edu for the postdoc position
Extended resources for Junker, J., R. McClure, J. Pomeranz, J. Wesner, B. Murry. Use of size spectra as a holistic indicator of change for fisheries and ecosystem management. Poster #46. AFS 2025 Annual Conference.PDF
Are you interested in the application of size spectra to ecosystem and fisheries management? See details.
The ISD arises from multiple theories in ecology and has potential as a universal indicator. However, our understanding of the macroecology of the ISD is limited, particularly for non-marine ecosystems, as most studies have been limited to small spatial or temporal scales. Multiple agencies routinely collect these data (e.g., NEON, LTER, fisheries agencies, etc.), but it is not currently possible to analyze macroecological or temporal trends in size spectra because the data have not been compiled and harmonized. Gathering these data will allow ecologists to quantify spatial and temporal variation in size-abundance scaling across freshwater ecosystems and to test theory-driven hypotheses for how that scaling responds to fisheries management decisions (e.g., changing regulations and harvest, stocking) and natural and anthropogenic change (e.g., species invasions, eutrophication, warming).
***** Are you a manager of fisheries data that collects body size information? Would you like to use size spectra as a potential management metric? *****
We are assessing the interest in broader use of size spectra for understanding and managing inland fisheries. This might include workshops at conferences like AFS, shared learning resource collections, web portals to automate analysis of community size spectra, or other opportunities for data syntheses.
If you are interested, please reach out to james.junker[at]unt.edu.
Below is an biased and incomplete bibliography of useful size spectra resources.
Sprules, W. G., and L. E. Barth. 2016. Surfing the biomass size spectrum: some remarks on history, theory, and application. Canadian Journal of Fisheries and Aquatic Sciences 73:477–495. DOI:10.1139/cjfas-2015-0115
Petchey, O. L., and A. Belgrano. 2010. Body-size distributions and size-spectra: universal indicators of ecological status? Biology Letters 6:434–437.DOI:10.1098/rsbl.2010.0240
White, E. P., S. K. M. Ernest, A. J. Kerkhoff, and B. J. Enquist. 2007. Relationships between body size and abundance in ecology. Trends in Ecology & Evolution 22:323–330.DOI:10.1016/j.tree.2007.03.007
Novak, B., B. A. Murry, J. S. Wesner, V. Gjoni, C. C. Arantes, E. Shepta, J. P. F. Pomeranz, J. R. Junker, K. Zipfel, A. Stump, L. E. Solomon, K. A. Maxson, and J. A. DeBoer. 2024. Threshold responses of freshwater fish community size spectra to invasive species. Ecosphere 15:e70090. DOI: 10.1002/ecs2.70090
Murry, B. A., and J. M. Farrell. 2014. Resistance of the size structure of the fish community to ecological perturbations in a large river ecosystem. Freshwater Biology 59:155–167. DOI: 10.1111/fwb.12255
Jennings, S., and J. L. Blanchard. 2004. Fish abundance with no fishing: predictions based on macroecological theory. Journal of Animal Ecology 73:632–642. DOI:10.1111/j.0021-8790.2004.00839.x
Persson, L., P.-A. Amundsen, A. M. De Roos, A. Klemetsen, R. Knudsen, and R. Primicerio. 2007. Culling Prey Promotes Predator Recovery Alternative States in a Whole-Lake Experiment. Science 316:1743–1746. DOI:10.1126/science.1141412
Blanchard, J. L., S. Jennings, R. Law, M. D. Castle, P. McCloghrie, M.-J. Rochet, and E. Benoît. 2009. How does abundance scale with body size in coupled size-structured food webs? Journal of Animal Ecology 78:270–280. DOI: 10.1111/j.1365-2656.2008.01466.x
Heneghan, R. F., J. D. Everett, J. L. Blanchard, and A. J. Richardson. 2016. Zooplankton Are Not Fish: Improving Zooplankton Realism in Size-Spectrum Models Mediates Energy Transfer in Food Webs. Frontiers in Marine Science 3. DOI: 10.3389/fmars.2016.00201
Trebilco, R., J. K. Baum, A. K. Salomon, and N. K. Dulvy. 2013. Ecosystem ecology: size-based constraints on the pyramids of life. Trends in Ecology & Evolution 28:423–431. DOI: 10.1016/j.tree.2013.03.008
Pomeranz, J. P. F., H. J. Warburton, and J. S. Harding. 2019. Anthropogenic mining alters macroinvertebrate size spectra in streams. Freshwater Biology 64:81–92. DOI: 10.1111/fwb.13196
Andersen, K. H., and J. E. Beyer. 2006. Asymptotic Size Determines Species Abundance in the Marine Size Spectrum. The American Naturalist 168:54–61. DOI: 10.1086/504849
Delius, G., F. Scott, J. Blanchard, and K. Andersen. 2024. mizer: Dynamic multi-species size spectrum modelling. manual.
Wesner, J. S., J. P. F. Pomeranz, J. R. Junker, and V. Gjoni. 2024. Bayesian hierarchical modelling of size spectra. Methods in Ecology and Evolution 15:856–867.DOI:10.1111/2041-210X.14312
Edwards, A. M. 2020. sizeSpectra: R package for fitting size spectra to ecological data (including binned data).
Edwards, A. M., J. P. W. Robinson, M. J. Plank, J. K. Baum, and J. L. Blanchard. 2017. Testing and recommending methods for fitting size spectra to data. Methods in Ecology and Evolution 8:57–67. DOI: 10.1111/2041-210X.12641
Edwards, A. M., J. P. W. Robinson, J. L. Blanchard, J. K. Baum, and M. J. Plank. 2020. Accounting for the bin structure of data removes bias when fitting size spectra. Marine Ecology Progress Series 636:19–33. DOI: 10.3354/meps13230
Pomeranz, J., J. R. Junker, V. Gjoni, and J. S. Wesner. 2024. Maximum likelihood outperforms binning methods for detecting differences in abundance size spectra across environmental gradients. Journal of Animal Ecology 93:267–280. DOI: 10.1111/1365-2656.14044