crabs, it may be necessary to establish tissue weights from weight- 

 length regression analysis. 



The model for calculating mean daily consumption rate (lijk) for fishery 

 species i, human subpopulation j, and area k is therefore: 



VjlklPi 



^'j" " /Vij; ? ^'''" " Mjk ? i/jki Tjk, 



(4) 



where: 

 lijkl 

 Nijk 

 Wijkl 



Pi 



Hjki 



Tjki 



= Mean daily consumption rate of species i for subpopula- 

 tion j, area k, and household 1 (kg/day) 



= Number of households (successful harvest trips) for 

 species i, subpopulation j, and area k 



= Weight of species i harvested by household 1 of subpopu- 

 lation j in area k (kg) 



= Proportion of cleaned edible weight of species i to total 

 harvested weight 



= Number of people in household 1 of subpopulation j in 

 area k 



= Time elapsed since last meal by household 1 of subpopu- 

 lation j in area k (days). 



When consumption rates (lijki) are log-normally distributed, a 

 geometric mean consumption rate may be calculated by log-transform- 

 ing the data before applying Equation 4 to calculate a mean consump- 

 tion rate. 



Consumption rate data may be summarized further by calculating 

 means across species, subpopulations, and areas. However, it should 

 be recognized that means of Ijjk across species do not represent actual 

 diet patterns for consumers of mixed-species diets. To calculate mean 

 consumption rates for mixed-species diets, all Ijjki should be summed 

 across species within a household before determining mean consump- 

 tion rates across households (Ijk): 



'- ? e 



= 2 



1 



/jjkl 



(5) 



N, 



ijk 



where: 



Ijki = Mean daily consumption rate of all fishery species for 

 household 1, subpopulation], and area k (kg/day) 



Njk = Number of households in subpopulation j and area k 



and other terms are defined above. 



Landolt et al.(1985) summarized the assumptions involved in calculat- 

 ing mean consumption rates (lijkl) by household as follows: 



• Consumption 



- Pi values are assumed as noted above 



- Catch was distributed evenly among consumers in household 



- People in household actually ate the entire cleaned catch 



56 



