As goes the water, so go the dragonflies. That's the finding of a new report from the IUCN concluding that one fifth of dragonflies and damselflies in the Mediterranean region are threatened with extinction as a result of increasing freshwater scarcity. Threats facing the insects include habitat degradation, pollution and climate change.

According to the IUCN report, "The Status and Distribution of Dragonflies of the Mediterranean Basin" (pdf), the assessment of 163 Mediterranean dragonflies and damselflies shows that five species are Critically Endangered, 13 are Endangered and 13 are Vulnerable under the IUCN's Red List of Threatened Species classification system. In addition, 27 species are considered Near Threatened. Six more species were so rare that the IUCN Dragonfly Specialist Group could not collect enough data to properly assess their status.

Of the 13 Mediterranean dragonflies classified by the IUCN as Endangered, nine are endemic to the region.

So why should we care about dragonflies? The report points out that healthy dragonflies and damselflies are an indication of healthy water supplies. If the insects disappear, it is a sign that local waters are in low supply or are unsafe. "For many countries, water resources are a key issue," according to the report, "and in the southern Mediterranean countries it is estimated that Egypt, Israel, Libya, Malta, Syria and the Gaza Strip, for example, are using more than their renewable water resources (primordial aquifers, for example). About 64 percent of Mediterranean freshwater is used for agriculture."

Because dragonflies are popular species and fun to watch, it's easy to tap volunteers to track and monitor their populations. This could help scientists monitor freshwater conditions and also turn dragonflies into "appreciated ambassadors for freshwater conservation," according to the report.

What do we do next to protect these species, along with key water supplies? "The selection and protection of key sites are essential to ensure the survival of these species," said IUCN's Annabelle Cuttelod, co-author of the report, in a prepared statement. "Their ecological requirements need to be taken into account in the planning and management of water use, especially for agriculture purposes or infrastructure development."

Image: The Glittering Demoiselle (Calopteryx exul), an endangered damselfly. © Jean–Pierre Boudot; courtesy of the IUCN