TY - JOUR
T1 - Bottom hypoxia alters the spatial distribution of pelagic intermediate consumers and their prey
AU - Dillon, Rebecca A.
AU - Conroy, Joseph D.
AU - Lang, Kathryn J.
AU - Pangle, Kevin L.
AU - Ludsin, Stuart A.
N1 - Funding Information:
We thank the technical staff from the Aquatic Ecology Laboratory and biologists from ODNR–DOW for help with field work and laboratory processing. This research was primarily supported by the Federal Aid in Sport Fish Restoration Program (F-69-P, Fish Management in Ohio), administered jointly by the US Fish and Wildlife Service and the ODNR–DOW (project FADR79 to SAL, RAD, and JDC). Additional monetary support was provided by a Mayers Summer Research Scholarship from The Ohio State University’s College of Arts and Sciences (to KJL). We thank Jennifer Pfaff for providing comments on a previous draft of the manuscript.
Publisher Copyright:
© 2021, Canadian Science Publishing. All rights reserved.
PY - 2021
Y1 - 2021
N2 - While recent research has shed insight into how bottom hypoxia affects pelagic food webs in coastal marine ecosystems and natural lakes, its effects on man-made lake (reservoir) food webs remains more incomplete. To address this gap, we conducted a study in two midwestern USA reservoirs to examine how the spatial overlap and vertical distributions of dominant zooplanktivores (i.e., pelagic fish, bentho-pelagic Chaoborus spp.) and their prey vary between periods of normoxia and hypoxia. Surprisingly, we found high levels of spatial overlap between zooplankton and both intermediate consumers (pelagic fish and Chaoborus) during both normoxia and hypoxia, though the extent of spatial overlap was higher during hypoxia at night relative to day. As expected, pelagic fish and zooplankton avoided hypoxic waters, and Chaoborus moved from hypoxic waters during the day to the well-oxygenated surface waters at night. Using our findings, we discuss the potential influence of bottom hypoxia and Chaoborus on the function and structure of north-temperate reservoir food webs.
AB - While recent research has shed insight into how bottom hypoxia affects pelagic food webs in coastal marine ecosystems and natural lakes, its effects on man-made lake (reservoir) food webs remains more incomplete. To address this gap, we conducted a study in two midwestern USA reservoirs to examine how the spatial overlap and vertical distributions of dominant zooplanktivores (i.e., pelagic fish, bentho-pelagic Chaoborus spp.) and their prey vary between periods of normoxia and hypoxia. Surprisingly, we found high levels of spatial overlap between zooplankton and both intermediate consumers (pelagic fish and Chaoborus) during both normoxia and hypoxia, though the extent of spatial overlap was higher during hypoxia at night relative to day. As expected, pelagic fish and zooplankton avoided hypoxic waters, and Chaoborus moved from hypoxic waters during the day to the well-oxygenated surface waters at night. Using our findings, we discuss the potential influence of bottom hypoxia and Chaoborus on the function and structure of north-temperate reservoir food webs.
UR - http://www.scopus.com/inward/record.url?scp=85102351996&partnerID=8YFLogxK
U2 - 10.1139/cjfas-2020-0001
DO - 10.1139/cjfas-2020-0001
M3 - Article
AN - SCOPUS:85102351996
VL - 78
SP - 522
EP - 538
JO - Canadian Journal of Fisheries and Aquatic Sciences
JF - Canadian Journal of Fisheries and Aquatic Sciences
SN - 0706-652X
IS - 5
ER -