07 September 2014

Dwarf Eel-grass in the Burry

Close inspection on non-flowering plants off Salthouse Point yesterday led me to the conclusion that my previous records of this genus were probably incorrect and that what I’d named previously as the narrow-leaved form of Eel-grass Zostera marina var. angustifolia (see HERE) were in fact Dwarf Eel-grass Z. noltei. This certainly fits in with the results of intertidal surveys carried out by CCW in 2000, 2004 and 2009, the results of which are combined in the distribution map below.
From a distance Dwarf Eel-grass appears as darker patches of mud (top photo), but closer inspection reveals an interwoven root system that traps sediment creating slightly raised domes of drier mud. In the Burry the Eel-grass community (NVC SM1) grows as sparse, mono-specific patches on the open mudflats lying just below the saltmarsh fringe, this being a broken mosaic of the pioneer communities of Common Cord-grass Spartina anglica (SM6) and Long-stalked Glasswort Salicornia dolichostachya (SM8).
Lava Spire Snails
The most obvious animal in these intertidal habitats is the Lava Spire Snail Hydrobia ulvae, which can be found at densities of >2000m-1, although evidence of other invertebrates was plentiful in this extremely productive zone of the marsh. See Ian Tew's earlier post HERE for some of the other inter-tidal fauna.
Lava Spire Snails on Common Cord-grass

1 comment:

Barry Stewart said...

I found some flowering and fruiting material that confirms the Burry plants are as suspected noltei