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DRAFT alleles will exhibit deviations from Hardy-Weinberg expectations. The presence of null alleles will certainly skew estimates of allele frequencies, estimates of population differentiation, and could potentially suggest inbreeding where none occurs. Null alleles can be detected through tests of deviation from Hardy-Weinberg expectations. Such analyses are presented in section 3.4. 3.4 Hardy-Weinberg equilibrium Locus Captive Salt Camp Coyote Camp Boulders r, 234 0.469 0.365 0.460 1 275 0.066 1 0.3158 - 225 0.009 0.078 1 1 .11$ -')'226 0.002 0.836 1 0.321 267 0.171 1 0.2018 - 300 0.908 0.201 0.3264 0.657 Table 1: Tests of Hardy-Weinberg equilibrium for loci by population. Captive fish are from Willow Beach. Elements in the table are probabilities associated with tests. The results presented in table 1 indicate that two loci are out of Hardy Weinberg equilib- rium in the captive population, but all loci in the wild populations exhibit Hardy Weinberg equilibrium. Deviation from Hardy Weinberg typically results from a reduction in the ob- served number of heterozygous individuals. Often, this deviation results from inbreeding. Wright's (1951) FIS measures the amount of this deviation. The values for (FIS) for the exceptional loci in Willow Beach are 0.113 and 0.116 for loci 225 and 226. Because all other locus X population combinations do not differ from the expectations under Hardy-Weinberg equilibrium, their values of FIS do not differ significantly from zero. The fact that this pat- tern does not repeat across all populations and that the majority of loci are in equilibrium suggests that there is not a systematic departure from random mating as expected under inbreeding, nor are null alleles a problem with these data. 3.5 Independence among loci Population Locus 1 Locus 2 probability under null Willow Beach (Captive) X300 X267 0.041 Table 2: Significant disequilibrium among loci per population. Only the single population X locus pair that exhibited significant association is presented. Linkage disequilibrium measures the statistical association among alleles at different loci. Several factors can influence this association. First, loci could be physically linked on the 5