Population Dynamics of Shrimps in Littoral Marine Waters of the Mekong Delta, South of Viet Nam

Abstract

The population dynamics of eight commercial species of shrimp (Haliporoides sibogae, Harpiosquilla harpax, Metapenaeus affinis, Metapenaeus brevicornis, Metapenaeus tenuipes, Parapenaeopsis cultrirostris, Parapenaeopsis gracillima and Parapenaeus maxilipedo) distributed in littoral marine zone of the Mekong Delta were investigated. Length-based stock assessment using FiSAT II software package was used to assess the growth and mortality parameters: Asymptotic size (L8), growth coefficient (K), total (Z) and natural (M) mortality, exploitation rate (E), recruitment pattern, current probability of capture and selectivity of fishing gears. Yield-per-recruit analyses were carried out showing different levels of the exploitation. Results showed that the maximum sustainable yield would be reached for an exploitation rate higher than the current one for each population. However, the size of first capture should be increased for every population. The findings indicated that the current exploitations of shrimp populations distributed in littoral marine zone of the Mekong Delta are under exploitation level for maximum sustainable yield; however, all the shrimp populations are subject to growth over-exploitation.

Recruitment pattern and catch per unit effort of the Black Tiger Shrimp (Penaeus monodon) in Andoni River System, Niger Delta Region of Nigeria

“…This corresponded to the findings of Amin et al (2009) who reported the highest recruitment of Acetes japonicus in the coastal waters of Malacca between April and June. Dinh et al (2010) recorded recruitment of eight shrimps species, having single peak; in May for Haliporodes sibogae and Parapenaeus gracillima; in June for H. harpax, Metapenaeus affinis and M. tenuipes while M. breviconis had its peak in July. Parapenaeus cultrirostris and P. maxillipedo were at their peaks in August; all having their peak during the rainy season which is in consonance with the result of the current study.…”

ASPEK BIOLOGI DAN PARAMETER POPULASI UDANG JINGA (Metapenaeus affinis H. Milne Edwards, 1837) DI PERAIRAN KOTABARU, KALIMANTAN SELATAN

“…Ukuran maksimum M. affinis dicapai pada umur sekitar 1,5 tahun atau sekitar 18 bulan. Bila dibandingkan dengan parameter pertumbuhan di beberapa lokasi yang berbeda, laju pertumbuhan udang jinga di daerah penelitian lebih tinggi dibandingkan di perairan Turki dan Vietnam serta memiliki persamaan di perairan Iran dan India (Kapiris et al, 2013;Dinh et al, 2010;Ansari et al, 2014., Leena & Deshmukh, 2009) (Tabel 2). Variasi pertumbuhan tersebut dapat disebabkan oleh perbedaan kondisi lingkungan perairan (temperatur, salinitas, pH) dan perbedaan makanan atau nutrien yang dikonsumsi oleh M. affinis dari masing-masing perairan (Manasirli,2012;Vijayan&Diwan,1995;Guillaumeetal.,1989).…”

“…Beberapa udang Penaeid di perairan yang berbeda memiliki laju pertumbuhan yang tinggi diantaranya di perairan Kakinada 10,58; di perairan Khoozestan 7,01 dan di perairan Vietnam 5,78 (Devi, 1987;Ansari et al, 2014;Dinh et al, 2010). Laju pertumbuhan dan laju kematian udang jinga yang tinggi menunjukkan udang jinga memiliki pertumbuhan yang cepat dan berumur pendek.…”

“…Hasil penelitian terkait aspek biologi dan parameter populasi udang jinga di lokasi yang berbeda menunjukkan bahwa udang jinga memiliki pertumbuhan yang cepat dan tingkat pemanfaatannya terlaporkan berada pada kondisi lebih tangkap (overfishing) di beberapa perairan yaitu perairan Iran, Vietnam dan Kuwait (Gerami et al, 2012;Leena & Deshmukh, 2009;Dinh et al, 2010;Mohammed, 1995). Informasi biologi dan parameter populasi udang jinga (M. affinis) di perairan Kotabaru hingga saat ini belum terlaporkan sehingga kajiannya perlu dilakukan sebagai evaluasi tingkat pemanfaatan dan bahan kebijakan pengelolaannya.…”

Estimation of Growth and Mortality Parameters for Two Penaeid Species of Tanzanian Coastal Waters

“…The results of the latter method are fairly reliable if one or two main recruitments occur every year. In addition to von Bertalanffy model the development of length-based stock assessment models made possible investigations of dynamics of fish stock population to be done [4,7]. The objective of this study was to estimate the growth parameters of the two species using the length-based stock assessment models in order to define the levels of exploitation.…”