Population Growth Model and Mortality of Pakistan Lobster (Panulirus polyphagus) in Estuary Waters of Tarakan City

Abstract

Lobster Panulirus polyphagus has a fairly high economic value and is found in the estuary waters of Tarakan City. This research aims to study the growth and mortality model of Lobster P. polyphagus originating in the estuary waters of Tarakan City. The research method was carried out using a quantitative descriptive method. Sampling was conducted 14 times from December 2021-May 2022 using gill nets. The results showed that the male sex ratio was more than the female. Allometric growth of males and females is negative allometric with a thin body shape. The structure of the size obtained was mostly in males ranging from 18.3-20.6 cm, and females around 20.5-22.2 cm. The maximum length growth of P. polyphagus based on von Bertalanffy's growth model was 31.519 cm in males and 31.374 cm in females. The total mortality (Z) of P. polyphagus for males and females was 1.104 and 1.119; catch mortality (F) of 0.106 and 0.253; natural mortality (M) of 0.998 and 0.866; exploitation rate (E) of 0.096 and 0.226, respectively. The high natural mortality causes the extinction of the Lobster species, so good management is needed so that it is sustainable.

Growth and mortality model of Chacunda gizzard shad Anodontostoma chacunda (Bleeker, 1852) in Tarakan waters, North Kalimantan, Indonesia

“…This can be done for sustainable management which is important for A. chacunda. Information on growth patterns and mortality has important information for the management of fishery resources for sustainable development (Indarjo et al 2023b).…”

“…The growth model of A. chacunda was analyzed using the length-weight relationship (Ferdoushi et al 2022) to determine fish stock conditions (Zahid et al 2022). The condition index value is an indicator value in analyzing the physiological and nutritional status of aquatic biota (Panicker and Katchi 2021), characteristics of growth patterns and age (Salim et al 2020a;Indarjo et al 2023b) using the Von Bertalanffy model (Indarjo et al 2022), and condition index analysis (Indarjo et al 2020a) used in fish physiology (Panicker and Katchi 2021) to analyze individual fish body shape (Salim et al 2021) or relative fish health within a specific population or individual (Salim et al 2020a). A mortality analysis model (Pauly 1984) was used Beverton and Holt formula to determine total mortality (Sparre and Venema 1999), catch mortality, natural mortality, and exploitation rate (Pauly 1984), indicating whether the fish has been optimally utilized (Ray et al 2023).…”