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.
Its been a while since I blogged about anything to do with the island and with the weather looking increasingly unsettled over the next few days, now seems like as good a time as any.
The breeding season is well and truly wrapped up and as such attention turned to migrant waders and summering spoonbills. The island did not disappoint, with some aggressive management of the water levels the island is a hotbed of migrant waders with the period from late July to August producing a good sprinkling of scarce waders and some very good numbers of common waders.
The first returning spotted redshanks and curlew sandpipers where recorded on the 23rd of July with 3 stunning summer plumage spot reds and 1 curlew sandpiper. Curlew sands have then been almost daily throughout the period with numbers peaking at an impressive 25 in early September. The first little stints appeared on the 21st of August with numbers peaking at 7 on the 23rd of August. Ruff passage has also been impressive, normally a rare bird on the island 3 have been summering on main lagoon. No doubts as a consequence of the dry conditions at other wetland sites. A personal highlight for me was a Green sandpiper on Belpers on the 22 of July, followed by three flying over on the same date.
Numbers of avocets have been steady at well over 600, along with over a 100 dunlin, over 300 redshanks, over a 100 black tailed godwits and scatterings of greenshanks, ringed plovers, sanderlings (another normally rare bird on the island) and bar tailed godwits. The first Snipe was flushed the other day and Common Sandpipers have been present throughout August.
The summering flock of Spoonbills took some time arriving, with numbers building up slowly from the 13th of July 2011, staying at 12 throughout late July and early August before peaking at 18 on the 23rd of August, soon after the flock relocated to Orfordness, leaving us with only two.
We’ve had the first scattering of passerine migrants with yellow wagtails passing through the island, the first wheatears, a Sedge warbler (the 1st for 5 years) and Chiffchaffs and Willow warblers.
A sure sign of the season changing is the arrival of a Kingfisher and the first wintering Robin, in addition Wigeon’s, Teals and Pintails have all started to build up on main lagoon. An unexpected highlight last week was a little gull, the first for three years and only the 26th ever record for the island.
It’s been a busy time for visitor events on the island with two open weekends and the Havergate adventure all taking place in August. All can be considered more or less a success, with over 500 people enjoying a trip out to the island over all the events. The Life+ project has also continued unabated with numerous visits from contractors and design consultants as we move inexorably closer to work starting in October.