Reasons For The Decline
The lacy elimia has disappeared from more than 90 percent of its historic range. The curtailment of habitat and range for this (and few other snail species) species in the Mobile Basin's larger rivers (Coosa River for lacy elimia) is primarily due to extensive construction of dams, and the subsequent inundation of the snail's shoal habitats by the impounded waters. This snail has disappeared from all portions of its historic habitats that have been impounded by dams.
Dams change such areas by eliminating or reducing currents, and thus allowing sediments to accumulate on inundated channel habitats. Impounded waters also experience changes in water chemistry, which could affect survival or reproduction of riverine snails. For example, many reservoirs in the Basin currently experience eutrophic (enrichment of a water body with nutrients) conditions, and chronically low dissolved oxygen levels. Such physical and chemical changes can affect feeding, respiration, and reproduction of these riffle and shoal snail species.
Read more about this topic: Lacy Elimia
Famous quotes containing the words reasons for, reasons and/or decline:
“The source of Pyrrhonism comes from failing to distinguish between a demonstration, a proof and a probability. A demonstration supposes that the contradictory idea is impossible; a proof of fact is where all the reasons lead to belief, without there being any pretext for doubt; a probability is where the reasons for belief are stronger than those for doubting.”
—Andrew Michael Ramsay (1686–1743)
“With what reason remains he reasons ill.”
—Samuel Beckett (1906–1989)
“Families suffered badly under industrialization, but they survived, and the lives of men, women, and children improved. Children, once marginal and exploited figures, have moved to a position of greater protection and respect,... The historic decline in the overall death rates for children is an astonishing social fact, notwithstanding the disgraceful infant mortality figures for the poor and minorities. Like the decline in death from childbirth for women, this is a stunning achievement.”
—Joseph Featherstone (20th century)