TY - JOUR
T1 - Complex to simple
T2 - Fish growth along the Illinois River network
AU - DeBoer, Jason A.
AU - Thoms, Martin C.
AU - Lamer, James T.
AU - Casper, Andrew Fowler
AU - Delong, Michael D.
N1 - Funding Information:
We thank Sabina Berry for processing channel catfish spines, Andrew Weiland for processing otoliths, Levi Solomon for acting as second reader for age estimation, and Travis Brenden and Derek Ogle for statistical consultation and code refinement. JDB was supported by an Australian Government Research Training Program (RTP) Scholarship from the University of New England. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Permission to handle our study animals was given by the University of Illinois, Institutional Animal Care and Use Committee, Protocols 14023 and 16152. Data are held within the University of New England, Australia, data repository:www.une.edu.au.
Funding Information:
We thank Sabina Berry for processing channel catfish spines, Andrew Weiland for processing otoliths, Levi Solomon for acting as second reader for age estimation, and Travis Brenden and Derek Ogle for statistical consultation and code refinement. JDB was supported by an Australian Government Research Training Program (RTP) Scholarship from the University of New England. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Permission to handle our study animals was given by the University of Illinois, Institutional Animal Care and Use Committee, Protocols 14023 and 16152. Data are held within the University of New England, Australia, data repository: www.une.edu.au .
Publisher Copyright:
© 2020
PY - 2021/1
Y1 - 2021/1
N2 - Fish growth in river ecosystems is influenced by a multitude of environmental drivers, including the heterogeneity of these drivers. Globally, river ecosystems are subject to anthropogenic stressors that can simplify riverine landscapes, homogenize riverine communities, and favor nonnative fishes. Yet, how anthropogenically driven simplification of riverine landscapes affects fish life-history traits remains largely unknown. The aim of this study was to examine the character of fish growth along the entire main channel of an Anthropocene River. We collected four species of potamodromous fish from different functional feeding guilds, from each of six functional process zones (FPZs) – unique large-scale hydrogeomorphic patches – along the entire length of the Illinois River (Illinois, USA), and calculated three growth metrics: growth rate (k), maximum size (L∞), and a relative growth index. The majority (7 of 12) of species-growth metric combinations did not differ among FPZs. Of the five species-growth metric combinations that were different, none exhibited more than three distinct groups of values. The limited difference in growth along the main channel of the Illinois River reflects a homogenization of ecosystem function, and is associated with the systemic simplification of physical heterogeneity of the river channel. The fishes studied from the Illinois River also tended to have faster growth rates (k) and smaller maximum sizes (L∞) relative to other North American freshwater ecosystems. Our results reveal spatial constraints to life-history traits and changes to ecosystem interactions, which are evidence of being in a new regime or state. This has implications for the reproductive output and resilience of native fishes in Anthropocene Rivers.
AB - Fish growth in river ecosystems is influenced by a multitude of environmental drivers, including the heterogeneity of these drivers. Globally, river ecosystems are subject to anthropogenic stressors that can simplify riverine landscapes, homogenize riverine communities, and favor nonnative fishes. Yet, how anthropogenically driven simplification of riverine landscapes affects fish life-history traits remains largely unknown. The aim of this study was to examine the character of fish growth along the entire main channel of an Anthropocene River. We collected four species of potamodromous fish from different functional feeding guilds, from each of six functional process zones (FPZs) – unique large-scale hydrogeomorphic patches – along the entire length of the Illinois River (Illinois, USA), and calculated three growth metrics: growth rate (k), maximum size (L∞), and a relative growth index. The majority (7 of 12) of species-growth metric combinations did not differ among FPZs. Of the five species-growth metric combinations that were different, none exhibited more than three distinct groups of values. The limited difference in growth along the main channel of the Illinois River reflects a homogenization of ecosystem function, and is associated with the systemic simplification of physical heterogeneity of the river channel. The fishes studied from the Illinois River also tended to have faster growth rates (k) and smaller maximum sizes (L∞) relative to other North American freshwater ecosystems. Our results reveal spatial constraints to life-history traits and changes to ecosystem interactions, which are evidence of being in a new regime or state. This has implications for the reproductive output and resilience of native fishes in Anthropocene Rivers.
KW - Heterogeneity
KW - Homogenization of ecosystem function
KW - Life-history traits
KW - Portfolio
KW - Resilience
KW - Stressors
UR - http://www.scopus.com/inward/record.url?scp=85097388879&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85097388879&partnerID=8YFLogxK
U2 - 10.1016/j.ecocom.2020.100891
DO - 10.1016/j.ecocom.2020.100891
M3 - Article
AN - SCOPUS:85097388879
SN - 1476-945X
VL - 45
JO - Ecological Complexity
JF - Ecological Complexity
M1 - 100891
ER -