Skip to main content
U.S. flag

An official website of the United States government

Evaluating spatial and temporal variability in growth and mortality for recreational fisheries with limited catch data

May 2, 2018

Understanding the spatial and temporal variability in life-history traits among populations is essential for the management of recreational fisheries. However, valuable freshwater recreational fish species often suffer from a lack of catch information. In this study, we demonstrated the use of an approach to estimate the spatial and temporal variability in growth and mortality in the absence of catch data and apply the method to riverine smallmouth bass (Micropterus dolomieu) populations in Pennsylvania, USA. Our approach included a growth analysis and a length-based analysis that estimates mortality. Using a hierarchical Bayesian approach, we examined spatial variability in growth and mortality by assuming parameters vary spatially but remain constant over time and temporal variability by assuming parameters vary spatially and temporally. The estimated growth and mortality of smallmouth bass showed substantial variability over time and across rivers. We explored the relationships of the estimated growth and mortality with spring water temperature and spring flow. Growth rate was likely to be positively correlated with these two factors, while young mortality was likely to be positively correlated with spring flow. The spatially and temporally varying growth and mortality suggest that smallmouth bass populations across rivers may respond differently to management plans and disturbance such as environmental contamination and land-use change. The analytical approach can be extended to other freshwater recreational species that also lack of catch data. The approach could also be useful in developing population assessments with erroneous catch data or be used as a model sensitivity scenario to verify traditional models even when catch data are available.

Publication Year 2018
Title Evaluating spatial and temporal variability in growth and mortality for recreational fisheries with limited catch data
DOI 10.1139/cjfas-2017-0052
Authors Yan Li, Tyler Wagner, Yan Jiao, Robert M. Lorantas, Cheryl Murphy
Publication Type Article
Publication Subtype Journal Article
Series Title Canadian Journal of Fisheries and Aquatic Sciences
Index ID 70196805
Record Source USGS Publications Warehouse
USGS Organization Coop Res Unit Leetown