This interactive Electronic Field Guide is designed to assist in the identification of some of the many invertebrates found in small streams throughout eastern Massachusetts. This version of the EFG does not cover all freshwater macroinvertebrates found in the region, but does include more than 100 genera found during invertebrate surveys in the major coastal watersheds. Streams ranging in size from tiny headwater springs to third-order tributaries were sampled, and both perennial and intermittent streams were investigated for macroinvertebrate fauna (see Site List for more details). Our aim is to enhance biological inventory and monitoring programs that require identification of stream invertebrates, to improve the efficiency and effectiveness of these important conservation efforts, and to inspire anyone else who might be deterred by the difficulties in aquatic invertebrate identification.
Information on the various organisms in this guide is based on various literature sources, as well as data acquired during recent collection efforts. An attribute of particular interest is the relative rarity or commonness of an organism, listed as ABUNDANCE. This information does not necessarily reflect the status of the organism region-wide, as many common aquatic invetebrates are not frequently found in small streams. An example of this is the Skimmer Dragonfly Libellula, a diverse genus that includes several common species frequently found in ponds and wetlands. Thus a species designated as "rare" may be common in other habitats, or could simply be difficult to find. On the other hand, a species designated as "lotic" [HABITAT] and "rare" [ABUNDANCE] is a prime candidate for more thorough investigation and future protection.