Louisiana Pearlshell (Margaritifera hembeli)
February 5, 1988 (endangered); reclassified threatened September 24, 1993.
For questions regarding the Louisiana Pearlshell, please contact Chris Davidson at email@example.com or 501-513-4481.
The Louisiana pearlshell is a medium-sized mussel with an oblong shell, growing up to 4 inches in length. This species is thought to have similar reproduction as other mussels: females release parasitic larvae (glochidia) that attach to the gills of specific species of host fish and later drop off as juvenile mussels. The host fish for the Louisiana pearlshell is unknown.
Louisiana pearlshell can be found on stable sand and gravel substrate in small, clear-flowing streams. It is known from three watersheds in central Louisiana. The only record of this species in Arkansas is from a specimen collected in the early 1900s in Bayou Dorcheat.
Why is it Endangered?
Dams and impoundments have had a large effect on this species, fragmenting and destroying habitat and populations. Beaver activity and dam construction has also been documented as a source of disruption to the distribution of this species across its range.
Sediment and stream bed scouring from human activities such as gravel mining, clear cuts, off-road vehicle use, and cattle creates unsuitable habitat for mussels and negatively impacts water quality.
The U.S. Forest Service has begun managing riparian zones within Louisiana pearlshell habitat in an effort to improve water quality and reduce sediment runoff.
Although beavers and Louisiana pearlshell are both endemic to the species' range and coexisted prior to listing, current habitat fragmentation and population isolation stemming from human-related activities have increased the threat from beaver activity. Beaver control has been used as a conservation tool in areas where they pose a local threat to Louisiana pearlshell.
Range in Arkansas: