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Studies of invertebrates at Aammiq
With the exception of such fascinating and beautiful creatures as butterflies and dragonflies, invertebrates lack "star quality." Yet the importance of invertebrates should not be underestimated. For one thing, perhaps three-quarters of all animal species are insects. For another, invertebrates have great ecological importance, providing a food source for many other creatures and lying at the base of the food chain. And finally, invertebrates are sensitive and rapid reacting indicators of the health of an ecosystem. Often the first sign of trouble in an environment is a change in the invertebrate community. Yet in Lebanon, invertebrates are very poorly known. In introducing its publication on national biological diversity in Lebanon, the Lebanese Ministry of Agriculture stated that "the lists included in this work are no longer up to date; there is an urgent need to undertake new studies in order to have complete information on the current state of the Lebanese freshwater fauna." The Aammiq Wetland in the Bekaa Valley, the focus of A Rocha Lebanon's work, has been thoroughly surveyed in terms of its vertebrate fauna over a period of six years. However, the aquatic invertebrate communities of Aammiq, like those of other freshwater habitats in Lebanon, are still relatively unknown. Even such groups as the spectacular dragonflies of the area remain under-appreciated. The result is that although the importance of Aammiq for aquatic invertebrate biodiversity in the Middle East is assumed to be high, exactly how high remains unknown. Invertebrates and managementThere are also practical issues to do with invertebrates at Aammiq. The wetland is a mosaic of many kinds of habitats, including reedbeds, flooded meadows, open water, flowing springs, small isolated pools and permanent and temporary waters. The task of wetland management that A Rocha Lebanon is involved in here will mean that some of these habitats will be expanded at the expense of others. But such actions raise hard questions that are best answered by studies on invertebrates: should pools be dug to create permanent water in areas that are now dry for several months of the year? Should we attempt to isolate certain parts of the marsh from fish predators such as the introduced Gambusia? Yet because we know so little about the diversity and abundance of the invertebrates in these different habitat types, we don't yet have the best basis on which to make such management decisions.
Methods
Sampling is being conducted at the following sites within the marsh area:
For each habitat type, sampling sites have been spaced as widely as possible within the marsh to maximise the chance of collecting the full range of species. Samples are taken where water is 20-30 cm deep, using a barrel sampler. The water depth, temperature and oxygen are measured, and the sampling location recorded using a global positioning system (GPS). All water and vegetation are then removed from inside the barrel sampler, and invertebrates separated out using a 250 micron mesh net. Back in the laboratory, the invertebrates are separated from remaining organic fragments and identified using a range of different reference works. DragonfliesAdult dragonflies and damselflies are collected on weekly field excursions to various parts of the Aammiq Wetland, and nearby ponds and streams in the West Bekaa throughout the spring and summer. Information recorded includes date and location of observation, numbers seen, species, sex and life stage of individuals collected. Collected specimens are pinned and stored. *** For further information on this project, contact lebanon@arocha.org |
 and Richard Storey (right) %E2%80%9Cpick bugs%E2%80%9D from samples of marsh water.jpeg?language=default "Brian Cousins (left) and Richard Storey (right) “pick bugs” from samples of marsh water")
