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The 'Phoenix' phenomenon continued:
<P>Some observations from Helen Reef near Palau, in April 2000:
<BR>Colonies of <I>P. cylindrica </I>at 4-5 m were partially dead on the
tips of the branches but the base of the colonies had survived. Notably,
many partially dead <I>P. cylindrica </I>colonies were recovering by the
following process: the basal portions had extended toward the tips of the
branches. This does not happen with most <I>Acropora</I> colonies (excluding
Isoporas that have no axial corallites) because they do not appear to be
able to initially extend laterally, which is necessary in this recovery
process, before extending distally, to the tips of the colonies. Therefore,
once an <I>Acropora</I> colony (with axial corallites) is damaged at the
tips of its branches the rest of the colony will usually die; the same
effects are seen for <I>Acanthaster planci</I> predation.
<P>(see MEPS 164: 213-220, 1998)
<BR>For massive <I>Porites</I>, regeneration commences by an initial 2-3
mm upward growth of the healing edge followed by lateral encroachment of
soft tissue and skeleton toward the lesion's centre within the first month.
Lesion scars are evident in core samples, there is usually a 1 mm
gap (see photos in above citation) and clearly the trabeculae and synapticulae
structures over the healed lesions are more porous than in other parts
of the colony. Indeed, their existence may help clarify the extent of historical
damage to Indo-Pacific <I>Porites</I> spp. through sclerochronological
investigations, and refine predictive models on the occurrence of small
lesions on <I>Porites</I> where some laudable sclerochronological studies
have already been carried out.
<P>Rob van Woesik
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<BR>Dr. Robert van Woesik
<BR>Associate Professor
<BR>Department of Marine Sciences
<BR>University of the Ryukyus
<BR>Nishihara, Okinawa 903-0123
<BR>JAPAN
<P>E-mail: b984138@sci.u-ryukyu.ac.jp
<BR>Website: <A HREF="http://www.cc.u-ryukyu.ac.jp/~b984138/">http://www.cc.u-ryukyu.ac.jp/~b984138/</A>
<P>Ph: (81) 098 895 8564
<BR>Fax: (81) 098 895 8552
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