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Reproductive activity of Pygospio elegans - Approximately 50% of the sexually
mature females sampled between March and June 1997 contained embryos and/or
larvae in their tubes (Figure 3.4). Reproductive activity decreased during the summer
and by October very few female tubes contained embryos or larvae. However,
reproductive activity increased again over the winter months and by February 1998,
the majority (81.2±12.5%) of female tubes again contained embryos or larvae. These
two increases in the proportions of mature females brooding larvae in their tubes
potentially explain the timings of larval recruitment. The high numbers of female
tubes containing larvae during the spring (Figure 3.4), approximately 50%, may have
been responsible for the cohort observed settling during May (Figure 3.2(iii)). It is not
possible to account for the December cohort in this way without sampling during
November when a high percentage of tubes containing larvae would have been
expected. The high percentage observed during February 1998 would presumably
have been responsible for a spring recruitment during 1998.
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,cs
60 —
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g 30 —
Et
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Mar Apr May Jun
I
Jul Aug Oct Dec
MONTH
-r
Feb
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czt
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—40 a.) ba
ez:
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Figure 3.4 : Mean number per core (bar graph) and percentage (line graph) of female
tubes containing embryos or larvae from March 1997 to February 1998 (± S.E.mean,
n=3).
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