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Increasing the value of surface water storage for protected wildlife, particularly the emblematic Cuvier’s Gazelle, in Mergueb Reserve (M’sila, Algeria). - The arid climate of the High Algerian Plateaux constitutes a limiting factor to the development of wild endangered Cuvier’s Gazelle (Gazella cuvieri) registered in IUCN’s red list. This antelope can utilize water from plants as well as dew, but it needs to visit waterholes frequently. In this semi-desert region, the classified nature reserve of Mergueb located in the M’sila Wilaya (Algeria) is the predilection area for Cuvier’s Gazelle. It is located south of Algiers in the main high steppes of Hodna and covers an area of about 16 482 hectares. It faces however the critical problem of water scarcity and surface water storage, vital for the survival of the gazelle. Precipitation in this arid region, with an annual average around 260 mm, is characterized by a large variability, with a sporadic and torrential distribution. Maximum monthly values are observed in May and from October to December. Months from June to September suffer important water deficit. The study undertaken in 2002 by the General Direction of Forestry (DGF) within the framework of G35 UNDP-DGF project led to the selection of sites to mobilize and store surface water for wild mammals to ensure water availability during periods of shortage. An integrated management scheme has been proposed, using simple techniques and local building materials at a minimum cost. It is represented by the ’Djobs traditional water storage system’ which description constitutes the core of the present paper. The choice of djobs as water storage system is based on: (1) simple building techniques adapted to the local materials; (2) a topography with very small watershed, where the runoff can be gathered and stored. Djob can be defined as a large shallow hole in the soil, or a small pond, that will store enough runoff water and will allow gazelles to easily use it without being scared. Favorable runoff catchment area for djob’s construction, should: (1) be clean, smooth, non-erosive and have small slope to slow down the runoff; (2) not require heavy equipment disturbing the environment; (3) provide local building materials and at a minimum cost; (4) be easy to clean and to restore; (5) allow the wild species to approach. Selected sites are characterized by: (1) their position across small shallow and very narrow thalwegs, thus requiring only an embankment to be built with local rocks and soil gathered from the stream channel bottom; (2) impermeable reservoir bottom and side wall reducing water loss; (3) limited dike height which is function of the amount of water to be mobilized and which should reduce surface water plan to limit evaporation. With this storing method, drinking water is available for a long period and the construction is easy to realize and does not disturb the environment, thus allowing wild livestock to settle. Because of the extreme intensity of the storms that may occur in the region, the dike resistance should be increased: (1) by curing the stream channel bottom and cleaning the banks (thalweg preparation); (2) by compacting the talus and its vegetation. Autumn rainfall is responsible for alluvial deposits in the djobs. Silt deposits inside these reservoirs are inevitable in these arid lands. However, the choice of the sites should minimize this effect; catchment area less than 63 000 m(2) with geological formations hard to erode should be favoured.

In conclusion, djobs are the solution for helping developing andprotecting Cuvier’s Gazelle. Their construction is simple to perform at a minimum cost. However, they should periodically be cleaned, controlled and fixed.