Population dynamics, reproduction and growth of the Indo-Pacific horned sea star, Protoreaster nodosus (Echinodermata; Asteroidea)
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The horned sea star (Protoreaster nodosus) is relatively common in the Indo-Pacific region, but there is little information about its biology. This study of the population biology of P. nodosus was carried out in Davao Gulf, The Philippines (7°5′N, 125°45′E) between September 2006 and May 2008. Protoreaster nodosus was found in sand and seagrass dominated habitats at a mean density of 29 specimens per 100 m2 and a mean biomass of 7.4 kg per 100 m2, whereas a significantly lower density and biomass was found in coral and rock dominated habitats. Adult specimens (mean radius R = 10.0 cm) were found at depths of 0–37 m, whereas juveniles (R < 8 cm) were only found in shallow sandy habitats with abundant seagrass (water depth ≤2 m). Increased gonad weights were found from March to May (spawning period), which coincided with an increasing water temperature and a decreasing salinity. Density and biomass did not change significantly during reproduction, but sea stars avoided intertidal habitats. All specimens with R > 8 cm had well developed gonads and their sex ratio was 1:1. Protoreaster nodosus grew relatively slowly in an enclosure as described by the exponential function G = 7.433 e−0.257 × R. Maturing specimens (R = 6–8 cm) were estimated to have an age of 2–3 years. Specimens with a radius of 10 cm (population mean) were calculated to have an age of 5–6 years, while the maximum age (R = 14 cm) was estimated as 17 years. Potential effects of ornamental collection on the sea star populations are discussed.
KeywordsPatch Reef Full Moon Seagrass Meadow Larval Period Intertidal Habitat
We greatly acknowledge E. Santos and K. Schröder for supporting the initiation of the project. We thank I. Ebol, C. Ganadores, E. Glimada, J. Lagarteja, B. Müller, S. Nitza, S. A. Nitza, D. Padrogane, C. Petiluna, M. Saceda, F. Salac, J. Salinas, I. Santamaria and R. Tejada for supporting the fieldwork. Furthermore, we would like to thank R. Scheibling, B. Wilkinson, and two anonymous reviewers for their comments on an earlier version of this manuscript. We for fine-tuning the English language. We are grateful to the communities from Samal Island and Talikud Island for sharing their knowledge of the local marine resources. The performed experiments complied with the current laws of the Republic of the Philippines.
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- Bos AR, Alipoyo JCE, Cardona LT, Gumanao GS, Salac FN (2008b) Population structure of common Indo-Pacific sea stars in the Davao Gulf, Philippines. In: Proceedings of 9th biannual meeting philippine association of marine science. UPV J Nat Sci 13 (accepted)Google Scholar
- Carpenter PH (1884) Report upon the Crinoidea collected during the voyage of HMS Challenger during the years 1873–1876. Part I: General morphology, with descriptions of the stalked crinoids. Rept Scientific Results HMS Challenger (s: Zool.) 11:1–422Google Scholar
- Clark AM, Rowe FEW (1971) Monograph of shallow-water Indo-West Pacific echinoderms No. 690. British Museum (Nat. Hist.), LondonGoogle Scholar
- Colin PL, Arneson C (1995) Tropical pacific invertebrates. Coral Reef Press, CaliforniaGoogle Scholar
- Feder HM, Christensen AM (1966) Aspects of asteroid biology. In: Boolootian R (ed) Physiology of echinodermata. Wiley, New York, pp 87–127Google Scholar
- Moran PJ (1988) Crown-of-thorns starfish: questions and answers. Australian Institute of Marine Science, TownsvilleGoogle Scholar
- Scheibling RE (1981b) Growth and respiration rate of juvenile Oreaster reticulatus (L.) (Echinodermata: Asteroidea) on fish and algal diets. Comp Biochem Physiol 69A:175–176Google Scholar
- Scheibling RE (1982) Habitat utilization and bioturbation by Oreaster reticulatus (Asteroidea) and Meoma ventricosa (Echinoidea: Spantagoidea) in a subtidal sand patch habitat. Bull Mar Sci 32:624–629Google Scholar
- Scheibling RE, Metaxas A (2008) Abundance, spatial distribution, and size structure of the sea star Protoreaster nodosus in Palau, with notes on feeding and reproduction. Bull Mar Sci 82:211–235Google Scholar
- Schoppe S (2000) Echinoderms of the Philippines. Times Edition, SingaporeGoogle Scholar
- Wabnitz C, Taylor M, Green E, Razak T (2003) From ocean to aquarium. UNEP-WCMC, Cambridge, UKGoogle Scholar