Habitat in and beside lakes & ponds
In 2002, Discovery Southeast began a 2-year study of amphibian habitat, principally within half a mile of the Juneau road system, but in following years branching out to other parts of northern Southeast Alaska. We (Armstrong, Willson and Carstensen) soon noticed that toad, frog and newt stillwater breeding habitat could almost be considered the inverse of aquatic habitats selected by anadromous fish.
In consequence, while moving waters important to the Southeast ‘money-fish’ (salmon and trout) have been intensively researched for more than a century, the quiet spawning ponds of inedible (even toxic!) herps are almost completely unstudied, and even unclassified.
For our study, a geomorphic classification seemed most appropriate. In other words, what are the geological and biological agents of pond formation. Here they are, listed roughly in order from most recent (and rapidly changing) to most ancient (and successionally stable):
human – anthropogenic
beaver – created and actively maintained by beaver
glacial – kettles, etc uncovered since peak of Little Ice Age
uplift – ponds on former tideland developed since Little Ice Age
fen – ponds on gently sloping sedge/herb dominated peatlands
bog – ponds in sphagnum-dominated peatlands
bedrock – controlled by bedrock, includes larger lakes