Definition: A taxon is Endangered when the best available evidence indicates that it meets any of the \r\ncriteria A to E for Endangered, and it is therefore considered to be facing a very high risk of extinction in the wild.
Definition: Gravel is an environmental material which is composed of pieces of rock that are at least two millimeters (2mm) in its largest dimension and no more than 75 millimeters.
Definition: A habitat that is in or on a body of water containing low concentrations of dissolved salts and other total dissolved solids (<0.5 grams dissolved salts per litre).
