Population dynamics,reproduction and growth of the Indo-Pacific horned sea star, <Emphasis Type="Italic">Protoreaster nodosus</Emphasis> (Echinodermata; Asteroidea) |
| |
Authors: | Arthur R Bos Joan C E Alipoyo Lemuel T Cardona |
| |
Institution: | (1) Research Office, Davao del Norte State College, New Visayas, 8105 Panabo City, The Philippines;(2) German Development Service, DED, 11th Floor PDCP Bank Center Building, VA Rufino corner LP Leviste Streets, Salcedo Village, 1227 Makati, The Philippines;(3) National Museum of Natural History Naturalis, P.O. Box 9517, 2300 RA Leiden, The Netherlands;(4) Department of Environmental Science, Radboud University, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands |
| |
Abstract: | 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.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|