African Journal of
Biotechnology

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12488

Full Length Research Paper

Biologic characteristics of Scomber japonicus (Houttuyn, 1782) in Tunisian waters (Central Mediterranean Sea)

Hassen ALLAYA1,2*, Abdallah HATTOUR2, Ghailen HAJJEJ2 and Monia Trabelsi1
1Faculty of Sciences, University Campus, University of Tunis, 2092 El Manar Tunis, Tunisia. 2National Institute of Sea Sciences and Technologies (I.N.S.T.M), 2025, Salammbô,Tunis, Tunisia.  
Email: [email protected]

  •  Accepted: 24 April 2013
  •  Published: 15 May 2013

Abstract

Some biological parameters of chub mackerel, Scomber japonicus, were studied in the Tunisian waters. A total of 368 specimens were collected between January 2009 and December 2010. The fork lengths ranged between 16.3 and 31.8 cm. Overall female: male ratio was 1:1.03. In the report of gonadosomatic index (GSI) and gonad macroscopic observation, spawning season was estimated to be from December to February and from June to August. The hepatosomatic index (HSI) increased in October-November and May in females, and increased in September-October and May in males. The length-weight relationships for S. japonicus, were Wt = 0.0119FL2,9909 for females, Wt = 0.0096FL3,0691 for males, Wt = 0.0111FL3,0186 for pooled data, indicating a significant isometry growth pattern (P<0,005) for the two sexes separately and for all samples.

 

Key words: Scomber japonicus, Tunisian water, sex ratio, growth, spawning.