Chaoborus (Diptera: Chaoboridae) mandibles—paleolimnological indicators of the historical status of fish populations in acid-sensitive lakes

摘要: Paleolimnological analyses of Chaoborus mandibles were used to assess the status fish populations over previous 150 300 years in five lakes from Adirondack region New York State. Windfall Pond (pH 6.5) has not acidified and currently viable populations. Big Moose Lake 5.0) recent years, number declined 14 1930's seven early 1980's. The occurrence only migratory (subgenus Sayomyia) cores indicated long term presence Lake. Brooktrout 5.0), Deep 4.7) Upper Wallface 4.8) have all three are fishless. (Sayomyia) was present throughout core, but entirely limnetic species, C. americanus, appeared topmost interval core. appearance americanus top core a elimination Lake, probably during 1970's. Elimination by 1940's inferred for because above 1930 level replaced trivittatus as dominant. Dominance that planktivorous never present. These results strongly suggest stratigraphic provide useful assessment general historical lakes. technique should be other regions, well applications than those concerning lake acidification.