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During the mid-May 'heatwave' I searched under the pier, on a warm thundery morning in the middle of a set of mediocre spring tides, the water receding just past the end of the pier.
As usual the pier piles were alive with Dogwhelks,
Nucella
lapillus, gorging on the Acorn Barnacles, Semibalanus balanoides,
and Mussels Mytilus edulis, that adorn
the metalwork. If you look very carefully at mussel shells that have been
opened, you will probably see a tiny round hole, where a Dogwhelk
may have spent up to a couple of days boring through with its tooth-like
radula. The mussel provides a substantial meal for the Dogwhelk.
Patches of Dogwhelk eggs could be found sheltered in the ironwork
crevices but not in the same numbers as in February and March.
Sea Anemones
There were many anemones to be seen with the Snakelocks
Anemone, Anemonia viridis, seeming to outnumber the Beadlet
Anemones, Actinia equina. The sea anemone Sagartia
troglodytes and its variations were ubiquitous, showing a seemingly
unlimited array of colour as their heads and tentacles were observed on
the sand surface, although they are firmly attached to rock below the surface.
(see Glaucus 04.04.39-41).
A single large specimen of the Plumose Anemone,
Metridium
senile, was found in one pool, a beautiful white individual, its fine
tentacles resembling cotton wool.
Many tiny Hermit Crabs, Pagurus
bernhardus, were found, most housed in topshells with a few in dogwhelk
shells, leaving their trail lines on the sand’s surface as they go about
their busy lives. There were also many small Shore Crabs, Carcinus maenas,
as well as one larger individual that must have recently peeled as it was
soft as jelly. There was no trace of its cast off shell. One large specimen
of the Edible Crab, Cancer pagurus, found wedged into a discarded
piece of downpipe, measured 15 cm across its carapace. A few
Hairy Crabs, Pilumnus hirtellus, were found hiding under some of
the less disturbed rocks.
Smaller crustaceans observed included a number of prawns,
Palaemon
sp. in the pools as well as the amphipod Gammerus locusta under
some of the stones.
Small Fish
Under the landing stage at the south end of the pier I discovered a Greater Pipefish, Syngnathus acus. It was lying perfectly still amongst some rusting pipe and metalwork and could easily have been missed by the unpractised eye.
Other fish present included a single Butterfish, Pholis gunnellus, a couple of Bullheads (or Sea Scorpions) Taurulus bubalis, and a single Rock Goby, Gobius paganellus.
One dampener from my trip was that a large number of stones had been previously turned over and not replaced. This is an ongoing problem which certainly appears to commence in the spring, often coinciding with the crop of peeler crabs. While most rockpoolers and bait collectors are aware of the damage this causes to the animal communities associated with these rocks and will replace them the way they were found, it only needs a small number of individuals to continually search in this fashion, to damage the short and long term ecology of the area.
December 1st and only 24 days to Christmas. The weather was dry but there was a very cold north-east wind blowing off the land, which made it very chilly underneath the pier head at low water. While the sea was reputedly a number of ° higher than the outside temperatures, hands became very cold once they had been immersed in the water pools.
At first glance the pools appeared quite barren and little was observed. A few Dogwhelks, NucelLapillus, were braving the elements and feeding on the acorn barnacles high on the pier piles, while at the pile bases more were observed along with groups of eggs. A large green Snakelocks Anemone, Anemonia viridis, caught my eye as it lay partly submerged. Its tentacles were spreadeagled out of the water, it drew a sorry comparison to a handsome expanded compatriot in a deeper pool nearby.
Turning Rocks
There were a few large boulders which promised something and when turned
over produced quite a varied menagerie. Large and small porcelain crabs
clung to the undersides of the rocks. Three Edible
Crabs, Cancer pagurus, lay partly submerged in the exposed sand
whilst prawns, Palaemon sp. relocated to other cover in sudden jerky
movements, one second and they had moved 50-70 cm.
Hairy CrabA single Hairy Crab, Pilumnus hirtellus, scurried off, most probably not amused at having been disturbed. This species of crab has one claw much larger than the other.
Small Fish
Three Long-spined Sea Scorpions (or Long-spined Bullheads), Taurulus bubalis, remained perfectly still, hoping their camouflage would assist in not betraying their location. This was in contrast to half a dozen rocklings. The bronze-brown rocklings were difficult to count, as the shallow rock pool water came alive when the rocks were lifted and rocklings disappeared in all directions.
Sea Anemones
Beadlet Anemones, Actinia equina, were present but not in large
numbers and they were easily outnumbered by Snakelocks Anemones. At the
most southern point of the pier I found a Dahlia Anemone,
Urticina
felina, one of the rarer anemones for this site. The disc and tentacles
spanned 10 cm in diameter, but it was disappointingly dull in colour, mainly
greys and dull reds, with much debris attached to the main column. Further
inshore, Snakelock Anemones became more numerous and a few more Beadlet
Anemones were found.
Sagartia troglodytesMany of the sandy pools contained the sea anemone Sagartia troglodytes although not in large numbers. Most of those present were in the size range of 20 mm across, including the tentacles.
Crabs
Shore Crabs, Carcinus maenus, were fewer than in the summer. A few small Hermit Crabs, Pagurus bernhardus, housed in dogwhelk shells lay quietly on the sand surface in the small pools. There may well have been many more if I had looked but by now my hands were freezing cold and it was definitely time to go home.
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