D. Salman

The reproductive biology of Parhyale basrensis Salman (Crustacea, Amphipoda) in the Shatt al-Arab river

Basic biological investigations on the intertidal amphipod Parhyale basrensis are made. The incubation period is 1–2 weeks. The generation time is 5–6 weeks. Females produce at least 4 broods before they die. The number of eggs carried by the female is a linear function of size of the female. Egg numbers varies from 4–37. Maturity occurs at a size of 4 mm for the female and 4·5 mm for the male. The breeding season is extending from late February to late November or December. Recruitment starts at the beginning of May. Successive broods may have different life spans. The maximum life span of the population is 13–15 months and the minimum life span is 6–7 months.

Abundance and seasonal migrations of the penaeid shrimp Metapenaeus affinis (H. Milne-Edwards) within Iraqi waters

Migration of Metapenaeus affinis (H. Milne-Edwards) from the Arabian Gulf to nursery grounds in the inland waters of Iraq extends from May/June to January/February. Shrimp ranging in size from 3–125 mm total length were found in inland waters. In the shallow waters of the Al-Assaflya small-sized shrimp only were caught, while in the Marshes large-sized shrimp were abundant. Maximum numbers of recruits were recorded when temperatures reached 23–25 °C. However, the discharge of the Shatt Al-Arab may also be an important factor regulating recruitment.The growth rates of small shrimp were higher than those of large ones. There mostly was, a preponderance of females over males. Spawning at sea appears to occur immediately after emigration. Gonad development was not observed. Commercial landings, at the two main fish markets at Basrah, during September–November 1985 averaged 1000 kg day−1.

Life cycle and population dynamics of Annina mesopotamica (Ahmed), (Isopoda, Flabellifera) in the Shatt Al-Arab Region, Basrah, Iraq

A population of the intertidal, ovoviviparous, cirolanid isopod Annina mesopotamica was studied at the Al-Chibassy tributary of the Shatt Al-Arab river from 14 May 1973 to 29 April 1974, and at the Garmat-Ali river of the Shatt Al-Arab, Basrah, Iraq from 5 November 1984 to 30 June 1986. Population density varied between 128 to 5760 individuals m−2 with a mean of 1218 m−2. Highest numbers occurred between June and September. Breeding extended for most of the year except November/January to February/March, although ovigerous females were present throughout the year. The incubation period varied with season, and was ca. 2 weeks during the warmest period, and about a month at lower temperatures. Egg numbers varied between 4 to 66 with mean 24. Brood size was linearly proportional to female size. The size frequency distribution of the population was polymodal with a predominance of females over males. Four different types of growth curves were found: exponential, concave, convex, and intermediate between concave and convex. Growth rate varied between 0.63 and 2.19 mm month−1. Mortality was higher among summer cohorts. Life span varied between 5 and 11 months.

Seasonal changes in zooplankton communities in the re-flooded Mesopotamian wetlands, Iraq

Non-directional re-flooding of the wetlands in southern Iraq, which were extensively drained during the 1990s, started in 2003. The change in species composition and abundance of rotifer and cladoceran communities together with their abiotic environment were studied for 15 months in the re-flooded wetlands. The re-flooded wetlands were characterized by higher salinity than typical freshwater inland marshes, and some rotifer and cladoceran species were characteristic of the saline, post-re-flooding environment. The changes in species composition and abundance of rotifers were mostly seasonal, demonstrated by the cyclic changes in principal component analysis and their positive relationships to water temperature. Al-Huwaiza Marsh is distinguished from the other two marshes (Central and Al-Hammar Marshes) and is characterized by relatively lower and stable salinity, close to neutral pH, near or above saturation DO, and lower SO4−2. These characteristics might explain the differences in recovery processes of zooplankton communities among the three marshes. The Jaccards similarity index for Cladocera revealed similarity between the two stations of each marsh (in terms of maximum densities recorded); however, this was not mirrored by Rotifera. Al-Huwaiza Marsh stations were very similar to each other, whereas the Al-Hammar and Central Marshes had one station of each very similar to the other station of the other marsh. Cladocera and Rotifera are predominantly freshwater species; Rotifera is more sensitive to water quality changes, particularly salinity, than the Cladocera. The observed seasonal cycles of zooplankton communities might suggest that the system was stabilizing during the study period. However, water supply shortages since 2008 continue to threaten the wetlands.

Stenothoe Irakiensis, a New Species of Stenothoid Amphipod From the Arabian Gulf

[Description de Stenothoe irakiensis sp. nov., un amphipode abondant dans une communaute encrassante presente sur une bouee relevee dans le golfe Arabique., Description de Stenothoe irakiensis sp. nov., un amphipode abondant dans une communaute encrassante presente sur une bouee relevee dans le golfe Arabique.]