Distribution, age and growth of the diamondback squid, Thysanoteuthis rhombus (Cephalopoda: Thysanoteuthidae) from the tropical Arabian Sea
Individuals in all life stages of the large oceanic diamondback squid Thysanoteuthis rhombus were observed in the southeastern Arabian Sea. A total of 82 individuals were collected from the Arabian Sea between February 2013 and December 2018. The length-weight relationship follows an allometric grow...
Published in: | Fisheries Research |
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Main Authors: | , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Elsevier
2020
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Subjects: | |
Online Access: | http://eprints.cmfri.org.in/14132/ http://eprints.cmfri.org.in/14132/1/Fisheries%20Research_2020_Sajikumar%20K%20K_Distribution,%20age%20and%20growth%20of%20the%20diamondback%20squid,%20Thysanoteuthis%20rhombus.pdf https://www.sciencedirect.com/science/article/pii/S0165783619303339 https://doi.org/10.1016/j.fishres.2019.105478 |
Summary: | Individuals in all life stages of the large oceanic diamondback squid Thysanoteuthis rhombus were observed in the southeastern Arabian Sea. A total of 82 individuals were collected from the Arabian Sea between February 2013 and December 2018. The length-weight relationship follows an allometric growth pattern. Age and growth were estimated by statolith increment analysis (n = 77) and demonstrated a rapid growth rate ranging from 1.42 to 4.80 mm dorsal mantle length (DML)/day. Based on back calculated hatch dates, T. rhombus spawned from May to December with a peak in July. Male and female squids matured at 6 months of age. The oldest individual was a mature female (655 mm DML) that was 220 days old with a growth rate of 2.97 mm DML/day. Differences in size-wise (DML) instantaneous growth rates were evident. Stomach content analysis revealed that fish and squid were the major prey of adults and sub-adults, while in juveniles, crustaceans were the dominant prey item. Ontogenetic differences in the diet were apparent. |
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