Length-weight relationship, growth and mortality of Anadara granosa in Penang Island, Malaysia: an approach using length-frequency data sets

• Published in: Journal of the Marine Biological Association of the United Kingdom Vol. 95; no. 2; pp. 381 - 390
• Main Authors: Mirzaei, Mohammad Reza, Yasin, Zulfigar, Shau Hwai, Aileen Tan
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01.03.2015
• Subjects: Age; Anadara granosa; Aquaculture; Datasets; Fisheries management; Fishing; Growth models; Intertidal zone; Mortality; Seawater; Penang Malaysia; Selangor Malaysia; Malaysia; ISEW, Malaysia; growth performance; West Coast of Malaysia; Cockle; length distribution; growth parameters; Anadara granosa; mortality; longevity; length-weight relationship; population dynamics
• ISSN: 0025-3154; 1469-7769
• DOI: 10.1017/S0025315414001337

Length-weight relationship, growth parameters and mortality rates of Anadara granosa in the intertidal zone of Balik Pulau, Penang Island, West Coast of Malaysia were investigated based on monthly length-frequency data (December 2011 to November 2012). A total of 548 individuals ranging from 11.25 to 33.13 mm size were subjected to analysis. Logarithmic relationship between the length and weight was Log W = 2.328 Log L − 2.537 (R2 = 0.922) for combined sexes. From this equation it was clear that the exponent ‘b’ value for A. granosa showed a negative allometric growth (b < 3). A von Bertalanffy growth function with an asymptotic length (L∞) of 35.40 mm and a growth constant (K) of 1.1 year−1 was established from length frequency distributions. The t0(−0.140) was estimated by substituting the L∞and K in the Pauly's equation. The sizes attained by A. granosa were 10.13, 14.36, 17.89, 20.82, 23.56 and 25.29 mm at the end of 2, 4, 6, 8, 10 and 12 months, respectively. The estimated growth performance index (Ø) was 3.13 while the estimated lifespan of the cockles was about 2.72 years at the study area. The estimated value of total mortality based on length-converted catch curve was Z = 3.02 year−1. The natural mortality (M) and fishing mortality (F) rates were 1.84 and 0.48 year−1, respectively. The exploitation level (E) of A. granosa was 0.20, which indicated slight fishing pressure on the stock.