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The new recruits were only sufficiently abundant for statistical analyses during May,
June and December 1997 and February 1998. Mean abundances per core of new
recruits for these months were rather similar for each patch replicate and, therefore, all
3 replicates were analysed for these months. The results of their indices of dispersion
are displayed in Table 7.2. These results suggest that new recruits, i.e., individuals
benthic for less than 1 month, were generally randomly distributed except during June
1997 when they were aggregated.
Figures 7.6(i-xii) present the density plots of the abundances of new recruits for these
months. Spatial autocorrelation analysis performed on these distributions revealed no
significant spatial structuring and the correlograms are therefore not shown. The
density plots suggest that the non-random distributions of new recruits during June
1997 probably resulted from patches which were smaller that the sampling unit, 3cm,
which probably explains why their spatial correlograms were non-significant.
Month v:m ratio pattern id pattern I,, pattern
1 1.428 Random 1.037 Random 0.385 Random
May 1997 2 1.841 **A 1.106 *A 0.501 *A
3 0.916 Random 0.986 Random -0.096 Random
1 3.677 ***A 1.522 *A 0.507 *A
June 1997 2 2.217 ***A 1.194 *A 0.502 *A
3 4.938 ***A 1.563 *A 0.508 *A
1 1.208 Random 1.038 Random 0.187 Random
December 1997 2 1.163 Random 1.050 Random 0.146 Random
3 1.423 Random 1.042 Random 0.213 Random
1 0.832 Random 0.961 Random -0.191 Random
February 1998 2 1.228 Random 1.066 Random 0.206 Random
3 1.441 Random 1.098 Random 0.397 Random
Table 7.2 : Indices of dispersion of P. elegans new recruits for the months with mean
densities greater than 3 individuals per core. A=Aggregated distribution where *
represents a statistical significance from random at p