Rock Pooling Destination: Seapalling, Norfolk, England

Rock Pooling Destination: Seapalling, Norfolk March 2013

The shore at Seapalling is influenced by a series of artificial sea defenses that have changed the dynamics of the shore to produce multiple bays comprised of sand with shingle berms in between. 

After a week of spring storms a variety of subtidal fauna had been washed up in the strand line:

Thousands of razor shells  washed up on the shore.

Common starfish (Asterias rubens) in an intertidal pool. Note the wide tubular shapes also present- these are the insides of the razor shells that had been washed up on the shore.

A subtidal polychaete worm (opheliidae).

A subtidal seacucumber (Thyone spp.)

A subtidal anemone (Possibly Urticina spp).

The dorsal side of a sea mouse (Aphrodita aculeata)

The ventral side of a sea mouse (Aphrodita aculeata)

Crabs

A female shore crab (carcinus maenas) with eggs referred to by fisherman as gravid or buried.

A squat lobster (galatheoidea)

A slipper limpet (Crepidula fornicata)

Common whelk shell with a slipper limpet  (Crepidula fornicata) living inside.

A mussel (Modioulus spp.) 

Rocky shore communities of the artificial sea defenses:

Barnacles, periwinkles, limpets, sparse dog whelks and fucoids charecterise this habitat. 

Biotope classification: LR.MLR (Moderate energy littoral rock).

Rocky shore communities have formed on the artificial sea defenses; barnacles, Limpets (Patella vulgata) and the small periwinkle (Melarhaphe neritoides ) charecterise the equivalent upper and mid shore of the sea defenses. 

 Barnacles and periwinkles occur in a distinct band on the sea defenses.

A barnacle 

The common starfish (Asterias rubens) and beadlet anemones (Actinia equina). A number of  common star fish were washed up during the recent storms and were found seeking refuge amongst the sea defenses.

Common starfish (Asterias rubens) that have been washed in take refuge in the shady pools of the artificial  sea defenses.

The common sunstar (Crossaster papposus)

Ulva spp and Porphyra spp are ephemeral red and green seaweeds characteristic of mid shore communities influenced by sand scour.

On extreme low tides the blue mussel (Mytilus edulis) can also be observed (photo taken in 2012)

Serrated wrack (Fucus serratus) occurs on the lower shore

Edible crab (Cancer pagurus) and common starfish (Asterias rubens) seek refuge in the crevices between the stones of the sea defenses after being washed up in the recent storms. 

The common starfish (Asterias rubens) and razor shells washed up by the recent storms.

Common Crustaceans of the shore

Common crustaceans of the rocky shore:

When it comes to rock pooling crustaceans are one of the most popular groups of marine organism; Crabs, Prawns, Shrimps, Sand Hoppers and Sea slaters are all familiar sea side fauna.  Crustaceans are mostly scavengers and will feed across the shore when the tide is in. When the tide is out the best place to look for crabs are under seaweed and beneath boulders, prawns and shrimps are most common in rock pools, sea slaters are usually higher up on the shore darting between crevices, whilst sand hoppers can be found amongst the strandline.

Below are images of the common species of crustacean you may encounter whilst rock pooling on the rocky shores of the UK:

Sea slater (Ligia oceanica) occurs on the uppermost shore and splash zone in and amongst crevices.

Sand hoppers (Taltrid amphipods) occur amongst the strandline of sandy shores.

Amphipods occur across the shore, usually amongst decaying seaweed or under boulders. 

A male and female amphipod embrace. 

Common Prawn (Palaemon spp) occurs in rock pools.

Common Prawn (Palaemon spp) occurs in rock pools.

Hermit crabs (Paguroidea) occur in rock pools.

Hermit crabs (Paguroidea) occur in rock pools.

The Green Shore Crab (Carcinus maenas) occurs across the shore amongst seaweed and beneath boulders.

Green Shore Crab (Carcinus maenas)

Green Shore Crab (Carcinus maenas), showing a defensive display after the boulder under which it was hiding was moved.

Green Shore Crab (Carcinus maenas) amongst anemone tentacles.

Green Shore Crab (Carcinus maenas) burried whilst the tide is out.

Green Shore Crab (Carcinus maenas) burried whilst the tide is out.

Velvet Swimming Crab (Necora puber) occurs under boulders of the mid to lower shore.

Velvet Swimming Crab (Necora puber)

Risso’s Crab (Xantho pilipes) occurs underneath boulders of the lower shore

Montagu’s Crab (Xantho hydrophilus) occurs underneath boulders of the lower shore.

Broad- clawed Porcelain Crab (Porcellana platycheles) occur on the under-side of boulders in the lower shore.

Broad- clawed Porcelain Crab (Porcellana platycheles)

Squat Lobster (Galathea squamifera) occurs underneath boulders of the lower shore.

Dynamene bidentata - Males and female underneath a boulder of the lower shore.

Dynamene bidentata - Males and female underneath a boulder of the lower shore.

Edible Crab (Cancer pagurus) Small specimens may be found underneath boulders of the lower shore.

Edible Crab (Cancer pagurus)Larger specimens are found in the subtidal.

Edible Crab (Cancer pagurus)Larger specimens are found in the subtidal.

Brown Shrimp (Crangron spp) occur in sandy habitats, just where the surf breaks and can become trapped in pools as the tide falls.

Majiidae are a family of crabs some of whom occur in the lower shore amongst algae and beneath boulders.

Common Spider Crab (Maja brachydactyla) occurs subtidally but may be encountered on low spring tides or, washed up on the shore.