Ecology of the burrowing amphipod, Pontoporeia affinis, in Lake Michigan / by Wayne Paul Alley.

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TABLE 12. Spearman rank correlation coefficients indicating the degree
of association that occurred between the patterns of seasonal abundance
of Pontoporeia affinis for the stations of the C transect and then respective depth zones.
C- 1 versus 10- 35m o422
C-2 versus 36-65m.467*
C-3 versus 65-105m.405
C-4 versus > 105m 515*
C-5 versus > 105m.432
C-6 versus 66-105m.175
C-7 versus 36-65m.266
* Significant at 5%
PATTERNS OF SPATIAL ABUNDANCE
All observations from each station of the five cross-lake transects
were pooled for the three sampling periods to provide information on the
spatial standing crop of Pontoporeia (Fig. 46). These results indicated
that its abundance at shallow inshore stations A-l and A-6 was lower
than at other stations on the A transects which were located at greater
depths and farther from shore. The remaining four transects show a
general tendency for average amphipod counts at the stations located in
the deeper portions of the lake to be less than the shallower inshore
stations. The standard deviations of amphipod density of the inshore
stations are generally greater than those of the deeper stations. Stations