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:
“One of the great reasons for the popularity of strikes is that they give the suppressed self a sense of power. For once the human tool knows itself a man, able to stand up and speak a word or strike a blow.”
—Charles Horton Cooley (1864–1929)
“Scepticism is an ability, or mental attitude, which opposes appearances to judgments in any way whatsoever, with the result that, owing to the equipollence of the objects and reasons thus opposed we are brought firstly to a state of mental suspense and next to a state of “unperturbedness” or quietude.”
—Sextus Empiricus (2nd or 3rd cen., A.d.)
“Where mass opinion dominates the government, there is a morbid derangement of the true functions of power. The derangement brings about the enfeeblement, verging on paralysis, of the capacity to govern. This breakdown in the constitutional order is the cause of the precipitate and catastrophic decline of Western society. It may, if it cannot be arrested and reversed, bring about the fall of the West.”
—Walter Lippmann (1889–1974)