Abstract
Ecosystem-based management relies on understanding how perturbations influence ecosystem structure and function (e.g., invasive species, exploitation, abiotic changes). However, data on unimpacted systems are scarce; therefore, we often rely on impacted systems to make inferences about ‘natural states.’ Among the Laurentian Great Lakes, Lake Superior provides a unique case study to address non-native species impacts because the food web is dominated by native species. Additionally, Lake Superior is both vertically (benthic versus pelagic) and horizontally (nearshore versus offshore) structured by depth, providing an opportunity to compare the function of these sub-food webs. We developed an updated Lake Superior EcoPath model using data from the 2005/2006 lake-wide multi-agency surveys covering multiple trophic levels. We then compared trophic transfer efficiency (TTE) to previously published EcoPath models. Finally, we compared ecosystem function of the 2005/2006 ecosystem to that with non-native linkages removed and compared native versus non-native species-specific approximations of TTE and trophic flow. Lake Superior was relatively efficient (TTE = 0.14) compared to systems reported in a global review (average TTE = 0.09), and the microbial loop was highly efficient (TTE > 0.20). Non-native species represented a very small proportion (<0.01%) of total biomass and were generally more efficient and had higher trophic flow compared to native species. Our results provide valuable insight into the importance of the microbial loop and represent a baseline estimate of non-native species impacts on Lake Superior. Finally, this work is a starting point for further model development to predict future changes in the Lake Superior ecosystem.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1146-1158 |
| Number of pages | 13 |
| Journal | Journal of Great Lakes Research |
| Volume | 47 |
| Issue number | 4 |
| DOIs | |
| State | Published - Aug 1 2021 |
Bibliographical note
Funding Information:We thank members of the Lake Superior Technical Committee (LSTC) and the LSTC Ecosystem Team for advice and data used in this model. We thank Cory Goldsworthy, E.J. Isaac, Jared Myers, Mark Ebener, Ben Michaels, Brad Ray, and Shawn Sitar for valuable insight and assistance with model input, Lori Evrard for assistance with figures, Tom Stewart, Dr. Ryan Lepak, Dr. John Janssen, and an anonymous review for providing insightful reviews on a draft of this manuscript. Funding for this project was from the College of Science and Engineering, University of Minnesota-Duluth Campus to Hrabik and Cooperative Training Partnership in Aquatic Toxicology and Ecosystem Research (EPA CR-83492801), awarded to the Regents of University of Minnesota. The findings and conclusions in this article are those of the author(s) and do not necessarily represent the views or the policies of the U.S. Fish and Wildlife Service or U.S. Environmental Protection Agency. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Funding Information:
We thank members of the Lake Superior Technical Committee (LSTC) and the LSTC Ecosystem Team for advice and data used in this model. We thank Cory Goldsworthy, E.J. Isaac, Jared Myers, Mark Ebener, Ben Michaels, Brad Ray, and Shawn Sitar for valuable insight and assistance with model input, Lori Evrard for assistance with figures, Tom Stewart, Dr. Ryan Lepak, Dr. John Janssen, and an anonymous review for providing insightful reviews on a draft of this manuscript. Funding for this project was from the College of Science and Engineering, University of Minnesota-Duluth Campus to Hrabik and Cooperative Training Partnership in Aquatic Toxicology and Ecosystem Research (EPA CR-83492801), awarded to the Regents of University of Minnesota. The findings and conclusions in this article are those of the author(s) and do not necessarily represent the views or the policies of the U.S. Fish and Wildlife Service or U.S. Environmental Protection Agency. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Publisher Copyright:
© 2021 The Author(s), the USGS
Keywords
- EcoPath
- Ecosystem function
- Ecosystem structure
- Trophic flow
PubMed: MeSH publication types
- Journal Article
