Login | Request Account (DAF staff only)

Spatial and fishing effects on sampling gear biases in a tropical reef line fishery

View Altmetrics

Welch, D. J., Mapstone, B. D., Davies, C. R. and Russ, G. R. (2010) Spatial and fishing effects on sampling gear biases in a tropical reef line fishery. Marine and Freshwater Research, 61 (10). pp. 1134-1146. ISSN 1323-1650


Article Link: https://doi.org/10.1071/MF09278


Biased estimates of population parameters for harvested stocks can have severe implications for fishery management strategy choices. Hook-and-line fishing gear is size-selective and therefore collects biased samples from wild populations. Such biases may also vary in space and time. To assess this assertion, we compared line- and spear-caught samples of the main target species of an Australian hook-and-line fishery to quantify relative bias in size and age structure estimates. We also assessed the consistency of biases among four fishery regions and between two management zones – areas open and closed to fishing. Fish less than 310 mm and younger than 4 years comprised a larger proportion of the speared than the line samples regardless of region or management zone. Conversely, hook-and-line sampled more fish in larger size classes (>370 mm) and older age classes (≥6 years) relative to spear fishing. These biases were qualitatively, but not quantitatively, consistent in all regions and management zones. This variation in sampling resulted in different inferences about regional and zone-related patterns in population size and age structure. We recommend careful consideration of sampling bias when drawing conclusions about regional and management zone effects on fish populations.

Item Type:Article
Keywords:bias, coral trout, Great Barrier Reef, hook-and-line, no-take zones, selectivity, spearfishing
Subjects:Aquaculture and Fisheries > Fisheries > By region or country > Australia > Great Barrier Reef
Aquaculture and Fisheries > Fisheries > Fishery research
Aquaculture and Fisheries > Fisheries > Methods and gear. Catching of fish
Live Archive:03 Apr 2024 23:28
Last Modified:03 Apr 2024 23:28

Repository Staff Only: item control page


Downloads per month over past year

View more statistics