Preliminary observations on the recruitment variability in <i>Tripneustes gratilla</i> (echinodermata: echinoidea) in three selected biogeographic regions in the Philippines

DOI

抄録

The sea urchin Tripneustes gratilla is an economically important resource found along reef flats in many areas in the Philippines. Monthly field monitoring was conducted in three marine biogeographic regions in the Philippines: Northwestern Luzon, Northern Mindanao and Southern Mindanao, to determine and compare the density and size frequency distribution of T. gratilla benthic recruits (40 mm test diameter) from July 2009 to May 2010. Preliminary results showed that the mean density of recruits was significantly higher in the Southern Mindanao (9.41 individuals/ 100 m2) and Northern Mindanao (5.42 individuals/ 100 m2) compared to Northwestern Luzon (only 0.28 individuals/ 100 m2). On the other hand, most of the larger-sized urchins (up to 92 mm) were recorded in the Northwestern Luzon, and adults (>60 mm) comprised up to 66% of the total density. The observed variability in the density and size frequency distribution of T. gratilla recruits is discussed based on the biophysical profiles of the three regions. Southern and Northern Mindanao seem more favorable for sea urchin recruitment compared to Northwestern Luzon. Our ability to repeatedly induce spawning every month and the prevalence of mature stages (up to 100%) of egg samples in the three regions so far indicate the possible regular supply of larvae in all the regions, however, the vulnerability of the recruit stage to the changing environment may differ across biogeographic regions.

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詳細情報 詳細情報について

  • CRID
    1390001205301739648
  • NII論文ID
    130004953709
  • DOI
    10.3755/galaxea.15.107
  • ISSN
    18833969
    18830838
  • 本文言語コード
    en
  • データソース種別
    • JaLC
    • Crossref
    • CiNii Articles
  • 抄録ライセンスフラグ
    使用不可

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