Lake trout historically supported the most valuable freshwater commercial fisheries in North America, but their populations crashed in parts of the Great Lakes during the 1950s and 1960s due to overfishing and invasive species.
Timothy P O'Brien
Timothy O’Brien is a Supervisory Fish Biologist stationed at the Great Lakes Science Center in Ann Arbor, Michigan.
Since 2004, I have conducted ecosystem assessments in Lake Huron and Lake Michigan that track long-term changes in fish populations. My work mainly focuses on Lake Huron where I lead the Pelagic Prey Fish Assessment Program. The field component of this research involves carrying out an integrated acoustic and mid-water trawl survey which includes Lake Huron’s three hydrogeomorphically distinct basins, the main basin, North Channel, and Georgian Bay. The primary deliverable of this work is to provide state, tribal, and provincial fishery managers with current data on abundance, size/age, and spatial distribution of prey-fish stocks that support fish species targeted in commercial and recreational fisheries. My research interests extend to include early life history processes in fish populations and factors affecting recruitment, growth variation, and distribution of important species including rainbow smelt (Osmerus mordax) and bloater (Coregonus hoyi).
I supervise of team of Biological Technicians in the Deepwater Sciences Branch who are responsible for conducting long-term fishery assessments in Lake Michigan and Lake Huron. Additionally, I oversee the fish age estimation laboratory for Lake Huron and Lake Michigan fishery assessment programs. In addition to my science program role, I serve as station supervisor for the Cheboygan Vessel Operations Base in Cheboygan, Michigan which is the home port for research vessels Sturgeon and Arcticus.
Professional Experience
Supervisory Fish Biologist, November 2017 – Present
Biological Science Technician (Fisheries), May 2011 - October 2017
Student Trainee (Biology), Student Career Experience Program, June 2008 - April 2011
Biological Science Technician (Fisheries) Term, January 2005 - May 2008
Student Services Contractor – February 2004-December 2004
Education and Certifications
M.S. 2010. Fisheries and Wildlife. Michigan State University, Department of Fisheries and Wildlife
B.S. 2004. Resource Ecology and Management. The University of Michigan, School of Natural Resources and Environment
Science and Products
Hydroacoustic data from uncrewed surface vehicle (USV) overtakes in Lake Superior, 2022
Lakebed features extracted from single-beam sonar in two Laurentian Great Lakes
Hydroacoustic data from uncrewed surface vehicle (USV) overtakes in Lakes Huron and Michigan, 2021
Multimedia related to this scientist
Lake trout historically supported the most valuable freshwater commercial fisheries in North America, but their populations crashed in parts of the Great Lakes during the 1950s and 1960s due to overfishing and invasive species.
Publications by this scientist
Archive of morphological data for the Coregonus artedi species complex of the Great Lakes, Lake Nipigon and Great Slave Lake
Paired comparisons with quiet surface drones show evidence of fish behavioral response to motorized vessels during acoustic surveys in Lake Superior
Intra-lake trends and inter-lake comparisons of Mysis diluviana life history variables and their relationships to food limitation
Large-scale variation in lakebed properties interpreted from single-beam sonar in two Laurentian Great Lakes
Status and trends of the Lake Huron prey fish community, 1976-2022
Comparison of traditional and geometric morphometrics using Lake Huron ciscoes of the Coregonus artedi complex
Status and trends of the Lake Huron prey fish community, 1976-2021
Status and trends of the Lake Huron prey fish community, 1976-2019
Status and trends of the Lake Huron prey fish community, 1976-2020
Replacement of the typical artedi form of Coregonus artedi in Lake Huron by endemic shallow-water Ciscoes, including putative hybrids
Status and trends of pelagic prey fish in Lake Huron, 2018
Spatial patterns of rainbow smelt energetic condition in Lakes Huron and Erie in 2017: Evidence for Lake Huron resource limitation
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
News about this scientist
Science and Products
Hydroacoustic data from uncrewed surface vehicle (USV) overtakes in Lake Superior, 2022
Lakebed features extracted from single-beam sonar in two Laurentian Great Lakes
Hydroacoustic data from uncrewed surface vehicle (USV) overtakes in Lakes Huron and Michigan, 2021
Multimedia related to this scientist
Lake trout historically supported the most valuable freshwater commercial fisheries in North America, but their populations crashed in parts of the Great Lakes during the 1950s and 1960s due to overfishing and invasive species.
Lake trout historically supported the most valuable freshwater commercial fisheries in North America, but their populations crashed in parts of the Great Lakes during the 1950s and 1960s due to overfishing and invasive species.
Publications by this scientist
Archive of morphological data for the Coregonus artedi species complex of the Great Lakes, Lake Nipigon and Great Slave Lake
Paired comparisons with quiet surface drones show evidence of fish behavioral response to motorized vessels during acoustic surveys in Lake Superior
Intra-lake trends and inter-lake comparisons of Mysis diluviana life history variables and their relationships to food limitation
Large-scale variation in lakebed properties interpreted from single-beam sonar in two Laurentian Great Lakes
Status and trends of the Lake Huron prey fish community, 1976-2022
Comparison of traditional and geometric morphometrics using Lake Huron ciscoes of the Coregonus artedi complex
Status and trends of the Lake Huron prey fish community, 1976-2021
Status and trends of the Lake Huron prey fish community, 1976-2019
Status and trends of the Lake Huron prey fish community, 1976-2020
Replacement of the typical artedi form of Coregonus artedi in Lake Huron by endemic shallow-water Ciscoes, including putative hybrids
Status and trends of pelagic prey fish in Lake Huron, 2018
Spatial patterns of rainbow smelt energetic condition in Lakes Huron and Erie in 2017: Evidence for Lake Huron resource limitation
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
News about this scientist