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Species point records from 1982 Jones Menai Strait littoral rock survey1982-Jones-Menai-Strait-littoral-rock-survey.csv

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RecordKey SurveyKey SurveyName SampleKey StartDate EndDate DateType LocationName DataType Latitude Longitude Projection AphiaId Species Uncertain Abundance_SACFORN Abundance_Count IsDead SampleComment
JNCCMNCR10221356 JNCCMNCR10000129 1982 Jones Menai Strait littoral rock survey JNCCMNCR10009618 1992-06-02 1992-08-02 DD Gorad-y-Gyt to Menai Suspension Bridge (Menai Strait) Point 53.2265199873352 -4.1510788774388 WGS84 140167 Lacuna crassior FALSE Not set Not set FALSE Freshwater drains down the cliffs in places, resulting in luxuriant growths of Enteromorpha intestinalis which extend into the upper littoral. Lichens are poorly developed on these rocks, though the Verrucaria band can be detected where Enteromorpha does not blanket the shore. This shore is one which was visited annually from the 1930's by Prof. W.R. Brambell's easter marine zoology course, both for the general fauna of the limestone ridge and for the upshore shale fauna at Gorad y Gyt. Records resulting from this intensive collecting are numerous, often listed under the general locality name Cae Coch. Of particular interest were the boring mollusca of the lower shore; Hiatella was plentiful in the limestone and Zirphaea crispata in the soft basement shales. Collecting of the latter by student parties occasionally resulted in some damage since intact animals can be obtained only by attacking the rock with a crowbar. However, this kind of activity is much less common at the present time. The shore has always been subject to considerable deposition of fine sediment and it is probably this more than any other factor which limits the range of the species. There is evidence, so far inconclusive, that there is, in fact, more fine sediment in suspension and being deposited within the Menai Strait than was formerly the case. A complete fucoid zonation is present but Pelvetia and, to a lesser extent, Fucus spiralis, are limited by the prevalence of mobile substrata in the upper part of the shore. On the limestone shelves the factor limiting fucoid colonisation is generally the accumulation of fine sediment in depressions on the platform but where the rock is available for settlement well developed plants occur. At the lower edge of the shore, Laminaria saccharina and L. digitata become dominant, the latter large and with long stipes which, since they often bear Palmaria palmata as an epiphyte, are sometimes mistaken for L. hyperborea. This was the level of the shore which received the most attention from student courses; few new records have been added since the early 1970's and the main activity on the shore is now angling. Many anglers may be present on some days but they do not appear to cause significant disturbance since this shore is not suitable for bait digging. The shore retains this essential character to the Menai Suspension Bridge. All along, its sheltered nature is marked by the close approach of the land vegetation; the lower-hanging branches of the trees are trimmed off by the upper limit of salt water level presenting the appearance of having been neatly trimmed by a mechanical cutter. There are several seepages of fresh water and also untreated sewage (fortunately from small outfalls), which have a localised effect, increasing the quantity of green algae, in particular Enteromorpha intestinalis and Ulva lactuca.