Foxtail Stonewort

This is a summer annual which germinates in spring or early summer and produces spores in late summer. It reproduces both sexually, by spores, and asexually via small bulbs (1) (2).

All the foxtail stonewort populations are located within Sites of Special Scientific Interest, Natural Nature Reserves and Special Areas of Conservation which provide protection from habitat destruction and endeavour to maintain and enhance existing populations (1) (3).

This is a medium-sized alga with simple, equal sized whorls, which are increasingly close together towards to top of the alga, resembling furry fox tails (1) (2).

As an alga that is specially adapted to tolerate nutrient-poor environments, the foxtail stonewort lives in natural and artificial brackish lagoons with small fluctuations in water level that never exceed two metres (1) (2) (3). Some animal disturbance helps reduce vascular competitors and so encourages foxtail stoneworts. Sand, gravel or pebbles are ideal substrates for growth (1).

The foxtail stonewort inhabits four sites on the south coast of England in Dorset, Hampshire and the Isle of Wight. One of these populations is substantial but the others are small. There are also scattered populations in Ireland, along Europe's northern coastline and the Mediterranean coastline as well as isolated populations in southern Africa (1) (2). Hebridean populations have also recently been discovered (2).

The foxtail stonewort is listed as Vulnerable and is fully protected under Schedule 8 of the Wildlife and Countryside Act 1981 (1).

The saline lagoon habitat which is home to this alga is under threat from land reclamation for industry, agriculture and recreation as well as from water pollution and changes in salinity as a result of interruptions to waterways (1). Nutrient enrichment following fertiliser run-off from farmland is a particular concern since it encourages the growth of vascular plants against which this specialised stonewort cannot compete (3).