Distribution and abundance of Hilsa, Tenualosa ilisha larvae in the Shatt Al-Arab River and East Al-Hammar Marsh

Abstract

The larvae of Tenualosa ilisha were surveyed in the present research at four stations in the Shatt Al-Arab River and East Al-Hammar marsh. The study was conducted from April 2013 to March 2014. Water temperature was ranged from 12°C in December to 38 °C in July at all stations. Salinity was changed from 9.35‰ in October to 36 ‰ in August at station A, while salinity changed was from 1.03 ‰ - 3.5 ‰ at stations B, C and D. A total of 185 T. ilisha larvae (5.0-20 mm TL.) were collected. Higher number of T. ilisha larvae was recorded at station C (88), comprised 47.56 % of the total fishes larvae collected, and the lowest number (23) was from station A, comprised 12.43 % of the total fishes larvae collected. T. ilisha larvae were found in the study region during eighth month of the year, from March to October. The highest abundance of larvae at station C in March was 3.28 larvae/10 m², and lowest was 0.14 larvae/10 m² at station D in April. Water temperature showed a significant positive correlations with abundance of T. ilisha larvae at stations A, B, C and D (r = 0.833, o.692, 0.890, 0.616 p < 0.05 respectively). While, the salinity showed negative correlations with abundance of T. ilisha larvae at stations A (r = -0.700, p < 0.05), and a weak negative correlations with stations B, C and D (r = -0.523, -0.455, -0.470 p < 0.05 respectively). The results sh0wed that Shatt Al-Arab river and East Al-Hammar marsh play a vital role in T. ilisha reproduction, may urgent plan need to it protect the spawning and nursery ground for larvae of this species.