Populations of once dominant reef building coral Acropora clathrata in Arabian Gulf is declining, mainly due to thermal bleaching and anthropogenic fac tors such as rapid urbanization, toxic wastes, destructive fishing practices, land reclamation and sedimentation. To actively restore coral populations, continuous supply of corals is required without causing damage to the existing reefs. In this study, as part of the coral gardening approach, mid water coral nurseries were constructed in Abu Al Abyad Island, United Arab Emirates following the coral tree nursery model. Six hundred fragments, with an aver age length of 6.32 cm (SD ±1.23 cm) of Acropora clath rata were mounted in the nursery and reared for 21 months while monitoring the health of the fragments continuously and estimating the growth rate and survivorship of the corals every three months. Only 9.8% of mortality was recorded in the entire study period, while a linear growth rate of 6.44 cm･year -1 (SD ±0.72) was achieved in the first 12 months and 9.25 cm･year -1 (SD ±0.63) in the re maining 9 months. Almost negligible mortality and satis factory growth of corals during the entire nursery period suggest that the coral tree nursery model is suitable for propagating A. clathrata in Arabian Gulf.

Reintroduction of once existing red mangrove, Rhizophora mucronata trials were carried out in Abu Dhabi, United Arab Emirates. Propagules were procured from Pakistan and cultured in a greenhouse before they were planted alongside existing Avicennia marina forest in two sites of Abu Dhabi emirate, Abu Al Abyad and Ras Ghanada Islands. This study documents the present condition of the plants after 11 years of plantation. Long term survival rate was as high as 81% in Abu Al Abyad while Ras Ghanada experienced a very low survival rate at 10%, primarily due to external factors. In contrast, Ras Ghanada plants showed higher growth with the mean height stands at 2.06 m (SD ± 0.31m), while in Abu Al Abyad it is 1.53 m (SD ± 0.36 m). In Abu Al Abyad, more than one third (36.4%) of surviving plants showed reproductive phenology, whereas in Ras Ghanada it was only 10.3%, despite of greater height classes. Many Rhizophora were also noticed with well-developed stilt roots. This study showed that Rhizophora mucronata can be planted in Abu Dhabi, despite the Emirate's harsh climatic conditions.

There is a necessity to protect and manage the marine ecosystem towards the conservation of the ecological equilibrium and in turn the sustainability of the fishery resources in Abu Dhabi, UAE. Marine stock enhancement (MSE) proved that releasing hatchery fingerlings of marine animals can improve the abundance of harvest beyond the level supported by natural recruitment. For such programme to be beneficial and economical, considerable investment and scientific efforts are required. Among the concerned entities in the United Arab Emirates, the Aquaculture and Marine Studies (AMSC) in Abu Al Abyad Island successfully released 59 million of juveniles of different finfish species and 96 million juveniles of prawn species in Abu Dhabi waters. In the context of conserving the ecological equilibrium, the AMSC was able to plant an area of 5,026 ha in various areas of Abu Dhabi Emirate with grey mangrove, Avicennia marina; culturing over 21,290 corals of Acropora sp., Porites sp., Cyphastrea sp and Psammocora sp. in an area of 0.5 ha nurseries in Abu Al Abyad and Yasat Islands which will later be transplanted in the degraded reef sites in both islands; and a well-established seagrass coverage of 2500 m2 was achieved in affected areas in Abu Al Abyad Island.

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