Fisheries Research Articles
Age-based demographic assessment of fished stocks of Lethrinus nebulosus in the Gascoyne Bioregion of Western Australia
Document Type
Article
Publication Date
10-5-2010
Journal Title
Fisheries Management and Ecology
ISSN
Print: 0969-997X Electronic: 1365-2400
Keywords
Catch-curve analysis, Performance indicator, Recreational catch, Stock assessment, Uncertainty
Disciplines
Aquaculture and Fisheries | Marine Biology | Natural Resources and Conservation | Natural Resources Management and Policy | Population Biology | Sustainability
Abstract
Age-based demographic analyses were undertaken to assess the current status of fished stocks of spangled emperor, Lethrinus nebulosus (Forsskål) in the Gascoyne Bioregion of Western Australia. Differences in age and growth characteristics were detected for samples collected from different assessment zones, with North Gascoyne fish observed to grow faster and reach a shorter average maximum length and younger average age than South Gascoyne fish. A significant difference in North Gascoyne catch-at-age data from different time periods demonstrated historical effects of fishing on population age structure. Instantaneous rates of fishing mortality (F) from catch-curve analyses of age–frequency data sampled for the North Gascoyne stock from recreational fishing catches from April 2007 to March 2008 were beyond the limit reference point compared with estimated instantaneous rates of natural mortality (M) (i.e. F > 1.5M), indicating that there is currently a risk to the sustainability of that stock.
Recommended Citation
MARRIOTT, R.J., ADAMS, D.J., JARVIS, N.D.C., MORAN, M.J., NEWMAN, S.J. and CRAINE, M. (2011), Age-based demographic assessment of fished stocks of Lethrinus nebulosus in the Gascoyne Bioregion of Western Australia. Fisheries Management and Ecology, 18: 89-103. https://doi.org/10.1111/j.1365-2400.2010.00754.x
