Estimating the length-weight relationship and relative condition factor of the Omani abalone (Haliotis mariae Wood, 1828)
DOI:
https://doi.org/10.1590/Keywords:
Length-weight relationship (LWR), Growth pattern, Relative condition factor (Kn), Haliotis mariae, Allometric growth, Isometric growthAbstract
This study examines the length-weight relationship (LWR), growth patterns, and relative condition factor (Kn) of the Omani abalone (Haliotis mariae), using data collected over 12 months from key fishing areas in Dhofar, Oman. The primary aim is to establish LWR equations and assess growth dynamics across size classes to enhance fishery management practices. The LWR equations derived were W = 0.000046 x L3.2417 for total weight and W = 0.000019 x L3.2764 for foot weight, both showing a high correlation between weight and shell length, indicating reliable predictive strength for estimating abalone size from weight. Growth analysis revealed isometric growth (in which body proportions remain constant with size) in smaller and larger abalones, whereas medium-sized individuals showed positive allometric growth (in which weight increases faster than length), likely reflecting changes associated with maturation stages. Kn values ranged from 1.003 to 1.011 throughout the study period and were consistently above or near one across the locations, highlighting stable condition and general health, with minor variations among regions. The findings provide a basis for estimating harvestable biomass and applying size-based monitoring in Omani abalone fisheries. Implementing LWR-based methods can strengthen regulatory enforcement and help sustain abalone populations, with broader implications for ecological and socioeconomic resilience. Future studies may build upon such findings by incorporating environmental parameters to further explore their influence on growth dynamics and health status.
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