Abstract:
A study to establish bioeconomic options for economic exploitation of Chambo (Oreochromis spp.)
fisheries of Lake Malombe was conducted between 2010 to 2012. Three models, logistic regression,
Univariate Autoregressive Integrated Moving Average and Gordon Schaefer bioeconomic models were
used in the analysis. Primary qualitative and quantitative data from fishers and consumers were
collected using a pretested semi structured questionnaire. Time series data from 1976 to 2011 was
generated from the Traditional Fishery Data Base at Fisheries Research Station. The logistic regression
analysis showed that the goodness of fit Hosmer and Lemeshow test yielded c2 (8) of 6.924 and was
insignificant at 0.05 (P = 0.214). The -2 Log Likelihood showed that the model fitted the data at an
acceptable level (P = 0.001). Six predictor variables (stratum, marital status, literacy, years in fishing
and daily working hours) were significant. Autoregressive Integrated Moving Average model (0, 1, 1)
was selected. From the selected model, at the current exploitation rate it was forecasted that Chambo
catches would decline to -1,111.80 tons in 2021 from 4,118 tons in 1976. From the Gordon Schaefer
dynamic model, it is estimated that the economic rent at maximum economic yield, is MK2.148 million
as compared to MK1.533 million at maximum sustainable yield. The Gordon Schaefer bioeconomic
model showed that high economic rents are associated with maximum economic yield than maximum
sustainable yield. Based on the bioeconomic analysis, it is recommended that Chambo fisheries be
managed at maximum economic yield, which implies reducing the current fishing effort.
