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AgENCy PERFORMANCE � CASE STUDy 1<br />

during the nine-month larval period and for the<br />

return to the WA coast of those that survived.<br />

The shift back towards more favourable<br />

oceanographic conditions, in particular with the end<br />

of the strong La Niña weather period as well as the<br />

return of a more normal Indian Ocean Dipole pattern<br />

of sea surface temperatures, provides a basis for<br />

some optimism for a return to normal puerulus<br />

(a) Rat Island − Preliminary May<br />

(b)<br />

Average settlement per collector<br />

20<br />

15<br />

10<br />

5<br />

0<br />

Settlement date (new moon)<br />

Recent years<br />

Long Term Average<br />

2007/08 2008/09 2009/10 2010/11 2011/12<br />

MAY<br />

JUL<br />

SEP<br />

NOV<br />

JAN−08<br />

MAR<br />

MAY<br />

JUL<br />

SEP<br />

NOV<br />

JAN−09<br />

MAR<br />

MAY<br />

JUL<br />

SEP<br />

NOV<br />

JAN−10<br />

MAR<br />

MAY<br />

JUL<br />

SEP<br />

NOV<br />

JAN−11<br />

MAR<br />

MAY<br />

JUL<br />

SEP<br />

NOV<br />

JAN−12<br />

MAR<br />

Average settlement per collector<br />

20<br />

15<br />

10<br />

5<br />

0<br />

Seven Mile Beach − Preliminary May<br />

2007/08 2008/09 2009/10 2010/11 2011/12<br />

MAY<br />

JUL<br />

SEP<br />

NOV<br />

JAN−08<br />

MAR<br />

MAY<br />

JUL<br />

SEP<br />

NOV<br />

JAN−09<br />

MAR<br />

MAY<br />

JUL<br />

SEP<br />

NOV<br />

JAN−10<br />

MAR<br />

MAY<br />

JUL<br />

SEP<br />

NOV<br />

JAN−11<br />

MAR<br />

MAY<br />

JUL<br />

SEP<br />

NOV<br />

JAN−12<br />

MAR<br />

Settlement date (new moon)<br />

Recent years<br />

Long Term Average<br />

81<br />

settlement levels. However, even if puerulus<br />

settlement returns to more normal levels during<br />

2011/12, it will be three to four years before the<br />

first wave of any improved recruitment enters the<br />

fishery. On that basis, conservative catch levels will<br />

continue to be necessary for the West Coast Rock<br />

Lobster Managed Fishery for the next few years.<br />

Figure 38. the graphs nearby show the average monthly settlement of rock lobsters that reach the puerulus<br />

stage from May 2007 to March 2012 and the actual settlement until May 2011 at (a) Rat Island<br />

(Abrolhos Islands) and (b) Seven Mile Beach puerulus collectors.

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