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

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It appeared that turbulence caused by waves might contribute
information about changes of Pontoporeia abundance in the lake. Information collected at the stations of the C, D, and E transects and wave
heights measured by the personnel of the three car ferries were utilized
in the subsequent statistical analysis. Wave heights were coded from 0
to 5 with a rank of one representing a wave one meter high, a rank of
two a wave two meters high, and so forth. The largest wave height
noted for a period three days prior to and including the sampling day was
recorded for the stations of each transect. The lake was treated as a
single system and then divided into two depth zones: 20-50 m and less
than 105 m. The shallowest station of the three transects was 20 m.
Table 7 shows the simple correlation coefficients of amphipod
abundance versus the environmental and biological parameters. There
does not appear to be any significant relationship between Pontoporeia
and wave height for the 20-50 m zone, less that 105 m, and all depths
combined. The multiple regression equations for these data also indicated that wave height is not associated with Pontoporeia abundance.
Unfortunately, the turbulence caused by waves would achieve its grestest
effects at depths less than 20 m, which would indicate that these results
are inconclusive.
SEASONAL DISTRIBUTION
In the investigation of the seasonal abundance patterns of Pontoporeia,
the fundamental question concerning the reliability of data collected at