A. K. Jaiswar

Growth, mortality and exploitation of bigeye scad, Selar crumenophthalmus off Mumbai, north-west coast of India

An investigation was carried out to study the growth, mortality and exploitation of bigeye scad, Selar crumenophthalmus off the Mumbai coast during September 2008 to August 2009. The von Bertalanffy growth equation was derived as Lt = 310 mm [1−exp {−1.4 year −1 × ( t −(−0.059 year))}] with the growth performance index (o’) of 3.13. The fishable lifespan of the species was 2+ years in Mumbai waters. Bigeye scad attains total length of 240 and 293 mm during its first and second year of life. The size at first capture ( L c ) was estimated as 240 mm (1+ year). The recruitment was continuous and throughout the year with a single pulse during August. Nearly 50% of the recruitment took place during August and September. The total, natural and fishing mortality rates were 4.62, 2.21 and 2.41 year −1 , respectively. The estimated exploitation ratio (0.52) was very close to the optimum value of 0.5. Hence, the stock can be considered as optimally over-exploited in Mumbai waters.

New Distributional Record of Flat Needlefish Ablennes hians (Valenciennes, 1846) (Beloniformes: Belonidae) in the North-Eastern Indian Ocean with Taxonomic Details

Present study is based on five specimens of flat needlefish Ablenneshians collected from Puri North (Lat. 19047′43.062″N, Long. 85049′38.5788″E), Odisha, India on 7 January 2018. Based on morphometric and meristic characters, the specimens were identified as Ablenneshians (family Belonidae), having laterally compressed body with a series of vertical bars, 26 to 27 anal fin rays, 24–25 dorsal fin rays, 13–14 pectoral fin rays, and single lobe of gonad. A.hians can be distinguished from other three species of needlefishes reported from northeast coast of India based on body shape (body strongly compressed laterally in A. hians vs. rounded in cross section in other three species), number of anal fin rays (24–28 in A. hians vs. 15–25), vertical bars on body (a series of vertical bars in A. hians vs. no vertical bars in others except for S. leiura where few vertical bars are present on anterior half of the body). The occurrence of flat needlefish along Odisha Coast revealed the extension of its known geographical distributional range i.e. from noth of Andhra Pradesh in the North-eastern Indian Ocean. Further, it is an addition to the ichthyofaunal biodiversity of northeast coast of India.

Extending Geographical Distribution Range of Reef Needlefish Strongylura incisa (Valenciennes, 1846) (Teleostei: Beloniformes: Belonidae) in the Eastern Indian Ocean with a Key to the Species of Needlefish Occurring in the Area

Present study deals with new distributional records of Strongylura incisa (Belonidae) based on five specimens collected from the Andaman Islands and Tuticorin Coast (Tamil Nadu), India during 2016–17. Specimens were identified by absence of scales at bases of dorsal and anal fins, 19–20 dorsal fin rays, 21–23 anal fin rays, 102–113 predorsal scales, dorsal fin origin over 4–5 anal fin rays, prominent elongate spot on cheek between opercle and preopercle, and double lobe of gonad. Strongylura incisa can be distinguished from its most similar congener S. leiura based on number of predorsal scales (100–125 in S. incisa versus 130–180 in S. leiura), dorsal fin origin over anal fin rays (4–6 in S. incisa versus 7–10 in S. leiura), number of gonad lobes (2 in S. incisa versus 1 in S. leiura) and colour characteristics (prominent elongate spot on cheek between opercle and preopercle in S. incisa versus black bar on cheek between opercle and preopercle and anterior region of the body in S. leiura). Present study provides the first documented record of S. incisa from the Andaman and Nicobar Islands and East Coast of India with an updated key for Strongylura species. Further, it is an addition to the ichthyofaunal biodiversity of the Andaman and Nicobar Islands and East Coast of India.

Fishery and stock status of cuttlefishes off Andhra coast, India with focus on the needle cuttlefish Sepia aculeata Van Hasselt, 1835

The fishery and stock status of cuttlefishes along the northern coast of Andhra Pradesh was studied with special reference to the needle cuttlefish; Sepia aculeata Van Hasselt, 1835. Cuttlefishes caught by trawlers along the coast of Andhra Pradesh contributed 68.29% of the total cephalopod landings of the state during the study period (2006-2016). The average annual cephalopod landing in Andhra Pradesh for the study period was 2991 t and the mean annual catch per hour (CPH) during 2006-2016 was 0.47 kg h-1. The cumulative sum (CUSUM) analysis indicated increasing trend in cuttlefish landings of the state during the study period. Stock status plots indicates that cuttlefish stocks along the Andhra Pradesh coast are in the “fully exploited” phase.