Allen, correct on that first part. Here is one of several 'landmark' papers on this relationship, by one of my college professors.... ArticlePDF Available Ribbed Mussels and Spartina Alterniflora Production in a New England Salt Marsh December 1984Ecology 65(6) DOI:10.2307/1937776 Authors: Mark D Bertness Brown University Download full-text PDF Read full-text Citations (220) References (36) Abstract The ribbed mussel, Geukensia demissa, is commonly found associated with the salt marsh cordgrass, Spartina alterniflora. Mussels attach to the basal portion of S. alterniflora stems with strong proteinaceous byssal threads and deposit fecal material on the surrounding sediment as a byproduct of their filter-feeding activity. Here I demonstrate by manipulating mussel densities in the field that the presence of G. demissa stimulates S. alterniflora growth, and examine experimentally a number of potential mechanisms of this facilitation. In the natural habitat, mussel density is positively correlated with increased grass height, biomass, and flowering, and experimental removal and addition of mussels in these habitats demonstrates that mussels stimulate both aboveground and belowground S. alterniflora production. In tall-form S. alterniflora habitat, net primary production is positively correlated with mussel density and soil nitrogen levels. Experiments in this habitat show that mussels increase soil nitrogen, and this increase in nutrients would appear to be responsible for stimulating S. alterniflora growth. On the seaward edge of the marsh, net primary production is strongly correlated with mussel density, but not soil nutrients. On the marsh edge, mussels are shown to bind sediments and prevent erosion and physical disturbance. The relationship between S. alterniflora and G. demissa appears to represent a facultative mu- tualism that leads to increased marsh net primary production and stability. While previous research has shown that S. alterniflora production increases G. demissa growth and reproductive success, G. demissa also has strong stimulating effects on S. alterniflora. Nonconsumer plant-animal interactions such as the G. demissa-S. alterniflora association are potentially important determinants of marsh growth, stability, and community structure that have not been previously appreciated. On 12/30/21, Allen Aigen <[log in to unmask]> wrote: > The pseudofeces and feces ejected by the mussels probably also helps build > up the sediment that is trapped between the Spartina stems, allowing the > area to keep up with moderately rising sea levels. The mussels often attach > to the Spartina below the surface.Allen Aigen > On Thursday, December 30, 2021, 11:51:03 AM EST, Harry Lee > <[log in to unmask]> wrote: > > The role of Geukensia demissa in the structure SE US saltmarshes was > mentioned in Lee (2009: 16, species 11): "An infaunal species typically > attaching to hard objects buried in the muck of the estuarine Spartina > community, of which it is an important member." > > The Ribbed Mussel's special combination of epifaunal and infaunal habits > provides a potent anchor for the root system of cordgrass and other flora in > the habitat. > > Harry > > > On 12/28/2021 7:09 PM, David Kirsh wrote: > > Dear Listers, > > I was alerted to this information by a news item on public radio. Ribbed > mussels play a leading role in the integrity of salt marshes and feral swine > are the nemesis. > > But I hadn’t heard about the wider threat of feral swine described in the > accompanying video. > > David Kirsh > Durham, NC > > https://www.savannahnow.com/story/news/2021/12/07/wild-hogs-mussels-coasts-climate-change/8881734002/ > > [log in to unmask] > - a forum for informal discussions on molluscsTo leave this list, click on > the following web > link:http://listserv.uga.edu/scripts/wa-UGA.exe?SUBED1=conch-l-L&A=1Type > your email address and name in the appropriate box andclick leave the > list.---------------------------------------------------------------------- > > > ---------------------------------------------------------------------- > [log in to unmask] - a forum for informal discussions on molluscs > To leave this list, click on the following web link: > http://listserv.uga.edu/scripts/wa-UGA.exe?SUBED1=conch-l-L&A=1 > Type your email address and name in the appropriate box and > click leave the list. > ---------------------------------------------------------------------- ---------------------------------------------------------------------- [log in to unmask] - a forum for informal discussions on molluscs To leave this list, click on the following web link: http://listserv.uga.edu/scripts/wa-UGA.exe?SUBED1=conch-l-L&A=1 Type your email address and name in the appropriate box and click leave the list. ----------------------------------------------------------------------