One of Havergate's star species but also one of its hardest to see as quietly gone about having a great year.
Starlet Sea anemone's have almost every protection and status imaginable. They have their own Biodiversity action plan (BAP), are a red book species in the United Kingdom and even internationally are classed as vulnerable by the IUCN (International union for conservation of nature). Which means they are officially threatened by extinction unless the circumstances effecting their status improve.
Starlet sea anemone's are actually a fascinating little species. At best 15mm in size but in reality no more than 10mm it is found only in brackish or saline lagoons and restricted to the south and south east coasts of the UK. They are a highly sedentary species, moving only occasionally. It buries it tubular body into the ground and leaves it mouth and arms above the mud. It feeds by using its arms to grasp food as it passes and passing it to its mouth.
Picture courtesy of Graham White
There reproductive habits are also fascinating, it produces asexually all year around, dividing itself into two and regrowing each half but also it is able to when conditions are good and resources plentiful reproduce sexually. The female releases masses of eggs and the males thousands of free swimming sperm. 7 days later after several larval stages a new Starlet sea anemone forms with just four tentacles growing the rest over the course of a week or two.
Last year a survey to establish a baseline of the species was conducted, consisting of a two day survey on all the lagoons, the results where disappointing..... Two days of walking around all the lagoons revealed at best a mere handful of starlets, perhaps no more than 5 or 6 for the entire island with entire lagoons including Doveys, Cottage flood and Belpers devoid of starlets.
How much it can change in a year? All lagoons have now been colonised or more accurately recolonised. North lagoon, which held at best two (remember this for the entire lagoon) from last year, now has a staggering amount of anemones. In some areas there where as many as 60 – 70 of the anemones per square metre. Gullery held much less relatively, with only 10 per square metre and distribution was very patchy. Belper's lagoons where the water has been kept all year around, numbers where robust with up to 20 per square metre, other areas prone to drying out where empty but this is no great surprise. Numbers where low but present in Cottage flood,a lagoon previously thought to be devoid of starlets. Finally, Dovey's lagoon after being completely empty last year held good amounts,second only to North lagoon, with in places as many as 30 per square metre.
I think they can also be considered a good indicator of the quality of our saline lagoons which despite the old creaking sluices and poor water distribution are still capable of providing good habitat.
The challenge now is to learn from was done this year to ensure that this species is adequately monitored in the future and also able to flourish.