Rockpooling Destination: Revisit West Penwith, April 2015

The rocky shore is a high energy environment comprised of boulders and bedrock with rock pools, crevices and gullies.

he rocky shore is comprised of boulders and bedrock with rockpools, crevices and gullies. Habitat classification: LR.HLR (High energy littoral rock) EUNIS: A1.1 , LR.FLR.Rkp (Rockpools) EUNIS:A1.41 and LR.FLR.Lic.(Lichens on supralittoral and littoral fringe rock) EUNIS: B3.11.

The high energy environment of the shore leads to an extended lichen zone, that descends over much of the boulder field, which apart from Littorinids is relatively barren. Patches of lichens extend further down into the barnacle communities, which dominate from the upper to lower shore, interdispersed by shallow coralline rockpools in the mid shore, and deeper cobble filled rockpools on the lower shore. As the low tide mark is reached wave tolerant seaweeds lace the gullies.

Habitat classification:

Substrate	LR (Littoral rock)
Habitat	LR.HLR (High energy littoral rock)	LR.FLR (Features of littoral rock)
Biotope complex	LR.HLR. MusB (Mussel and/or barnacle communities)	LR.FLR.Lic.(Lichens on supralittoral and littoral fringe rock).		LR.FLR.Rkp (Rockpools)
Biotope		LR.FLR.Lic.Ver (Verrucaria Maura on  littoral fringe rock)	LR.FLR.Lic.YG (Yellow and grey lichens on supralittoral rock)	LR.FLR.Rkp.Cor (Coralline crust dominated shallow eulittoral rockpools)
SubBiotope				LR.FLR.Rkp.Cor.Bif (Bifurcaria bifurcata in shallow eulittoral rockpools)

Below are images of the organisms you may encounter in these habitats:

Lichens characterise the supralittoral and littoral fringe with periwinkles among the boulders. The littoral fringe of the boulder field does not support vast expanses of tar lichen (Verrucaria maura) which covers more stable bedrock of the littoral fringe, however, the mobile species found among the boulders on the littoral fringe are consistent with that of the V. maura biotope.  Habitat classification: LR.FLR.Lic.YG (Yellow and grey lichens on supralittoral rock) and LR (Littoral rock).

Examples of lichens found in the supralittoral:

Periwinkles are the most prolific mobile fauna of the boulder field, where they seek refuge within crevices. Rough periwinkles (Littorina compressa nigrolineata) and occasional barnacles. Habitat classification: A possible variant of LR.FLR.Lic.Ver (Verrucaria Maura on  littoral fringe rock).

                           

                           Littorina saxatilis agg

 Littorina compressa var. nigrolineata

Bedrock on the mid shore support barnacle communities and coralline rockpools. Within the barnacle communities beadlet anemones and increased numbers of gastropods can be found within the crevices, whilst limpets aggregate on the leeward sides of the rock and Lichina pygmaea forms tufts on the rock tops.
Habitat classification: LR.HLR. MusB (Mussel and/or barnacle communities) EUNIS: A1.11 and LR.FLR.Rkp.Cor (Coralline crust dominated shallow eulittoral rockpools) EUNIS: A1.411.

The lichen , Lichina pygmaea  forms small bushy growths on the boulders, often supporting increased numbers of small periwinkles (Melarhaphe neritoides). In April the lichen appears somewhat greenish, by comparison to previously in the year. (See blog post http://thesaltyscavenger.blogspot.co.uk/2014/02/rockpooling-destination-west-penwith.html)

A young crab feeds upon a M. neritoides

Barnacles and limpets (Patella sp)

Barnacles and M. neritoides

As the lower shore is reached the abundance of barnacles and Patella depressa increases.

The rockpools on this high energy shore are characterized by the presence of coralline seaweeds that make the rockpools appear as if they have been covered in a layer of pink paint. Habitat classification: LR.FLR.Rkp.Cor (Coralline crust dominated shallow eulittoral rockpools) EUNIS: A1.411.

Brown seaweeds that were absent in October, now grow in the rockpools. (See blog post: http://thesaltyscavenger.blogspot.co.uk/2015/05/rockpooling-destination-revisit-south.html)

China limpet (Patella ulyssiponensis)

P. ulyssiponensis

P. ulyssiponensis

P. ulyssiponensis interacting.

Common blue mussels (Mytilus edulis)  and Corallina officinalis occur within a crevice of a coralline rockpool.

A blenny and limpet.

Deeper rockpools support a higher diversity of seaweed species including, a greater abundance of Corallina officinalis and the brown forking weed (Bifurcaria bifurcata). Habitat classification: LR.FLR.Rkp.Cor.Bif (Bifurcaria bifurcata in shallow eulittoral rockpools) EUNIS: A1.4113

The invasive Sargassum muticum

Chondrus crispus

Chondrus crispus

Anemonia viridis

Grey topshell (Gibbula cineraria)

Rockpooling Destination: Revisit South- West Penwith, October 2014 - Lichen Communities of the shore

The rocky shore is a high energy environment comprised of boulders and bedrock with rock pools, crevices and gullies.

The rocky shore is comprised of boulders and bedrock with rockpools, crevices and gullies. Habitat classification: LR.HLR (High energy littoral rock) EUNIS: A1.1 , LR.FLR.Rkp (Rockpools) EUNIS:A1.41 and LR.FLR.Lic.(Lichens on supralittoral and littoral fringe rock) EUNIS: B3.11.

The high energy environment of the shore leads to an extended lichen zone, that descends over much of the boulder field, which apart from Littorinids is relatively barren. Patches of lichens extend further down into the barnacle communities, which dominate from the upper to lower shore, inter dispersed by shallow coralline rockpools in the mid shore, and deeper cobble filled rockpools on the lower shore. As the low tide mark is reached wave tolerant seaweeds lace the gullies.

Winter waves had washed many 'by the wind sailors' (Velella velella) onto the shore. These extraordinary creatures are not one, but many organisms that form a colonial hydroid that floats on the oceans, driven by the wind against its sail. During winter storms hundreds can be washed up onto the shores of the Lands' End peninsular.  

'By the wind sailors' (Velella velella) are often washed up on the Cornish shores over Winter.

V. velella use their dorsal projections as a sail to sail across the oceans in search of small pelagic prey, which they catch with their stinging tentacles.

Habitat classification of the shore:

Substrate	LR (Littoral rock)
Habitat	LR.HLR (High energy littoral rock)		LR.FLR (Features of littoral rock)
Biotope complex	LR.HLR. MusB (Mussel and/or barnacle communities)	LR.HLR.FR (Robust fucoid and/or red seaweed communities)	LR.FLR.Lic.(Lichens on    supralittoral and littoral fringe rock).		LR.FLR.Rkp (Rockpools)
Biotope			LR.FLR.Lic.Ver (Verrucaria Maura on  littoral fringe rock)	LR.FLR.Lic.YG (Yellow and grey lichens on supralittoral rock)	LR.FLR.Rkp.Cor (Coralline crust dominated shallow eulittoral rockpools)
SubBiotope			LR.FLR.Liv.VerB (Verrucaria maura and sparse barnacles on exposed littoral fringe rock)		LR.FLR.Rkp.Cor.Bif (Bifurcaria bifurcata in shallow eulittoral rockpools)

Habitat classification of the shore anticlockwise from the top of the shore down:
 LR.FLR.Lic.YG (Yellow and grey lichens on supralittoral rock)
 LR.FLR.Liv.VerB (Verrucaria maura and sparse barnacles on exposed littoral fringe rock)
LR.FLR.Lic.Ver (Verrucaria Maura on  littoral fringe rock)
  LR.HLR. MusB (Mussel and/or barnacle communities)
 LR.FLR.Rkp.Cor (Coralline crust dominated shallow eulittoral rockpools)
A crevice within the habitat LR.HLR. MusB (Mussel and/or barnacle communities)
 LR.FLR.Rkp.Cor.Bif (Bifurcaria bifurcata in shallow eulittoral rockpools)
and LR.HLR.FR (Robust fucoid and/or red seaweed communities).

Below are images of the organisms you may encounter in the lichen communities of the shore:

Lichens cover boulders of the supralittoral and littoral fringe. Yellow and grey lichens cover the boulders of the supralittoral  and below the black Tar lichen covers the boulders of the littoral fringe. LR.Flr.Lic.YG (Yellow and grey lichens on supralittoral rock) EUNIS: B3.111 and LR.FLR.Lic.Ver (Verrucaria Maura on  littoral fringe rock) EUNIS: B3.113.

 Yellow and grey lichens cover the boulders of the supralittoral. Habitat classification: LR.Flr.Lic.YG (Yellow and grey lichens on supralittoral rock) EUNIS: B3.111.

Tar lichen (Verrucaria Maura) covers the boulders of the littoral fringe. Habitat classification: LR.FLR.Lic.Ver (Verrucaria Maura on  littoral fringe rock) EUNIS: B3.113.

Periwinkles are the most prolific mobile fauna of the boulder field, where they seek refuge within crevices. Rough periwinkles (Littorina compressa nigrolineata) and occasional barnacles. Habitat classification: A variant of LR.FLR.Liv.VerB (Verrucaria maura and sparse barnacles on exposed littoral fringe rock) EUNIS: B3.1131.

Rough periwinkles (Littorina sp) and sparse barnacles.

Sparse barnacles, Small periwinkles (Melarhaphe neritoides) and Rough periwinkles (Littorina compressa nigrolineata) aggregate within pits and a depression of the boulder faces. 

Littorina compressa nigrolineata, sparse barnacles and limpet (Patella vulgata).

Littorina compressa nigrolineata

Littorina compressa nigrolineata

Rockpooling destination: St. Loy, Cornwall October 2014 - Supralittoral - Upper shore

The shore is a high energy environment, comprised of boulders and bedrock, with crevices, rock pools and gullies.

 

Fauna are relatively sparse among the spralittoral and upper shore boulders, increasing within the rockpools, crevices and gullies of the mid and lower shore bedrock.

The upper most shore is charecterised by lichen communities, whilst barnacle communities occur across the rest of the shore, inter-dispersed by coralline rockpools and as the lower shore is reached, robust fucoids and red seaweeds come to dominate.

A river flows onto the shore and beneath the boulders, until it emerges again on the shore, this time marked by an increase in ephemeral green algae.

Where conditions are sheltered enough, a strandline of kelp occurs.

Habitat classification: (Supralittoral - Upper shore)

Habitat	LR.HLR (High energy littoral rock)	FLR (Features of littoral rock)				LS.LSa (Littoral sand)
Biotope complex	LR.HLR. MusB (Mussel and/or barnacle communities)	LR.FLR.Lic.(Lichens on supralittoral and littoral fringe rock).			LR.FLR.Eph (Ephemeral green or red seaweed communities	LS.LSa.St (Strandline)
Biotope		LR.FLR.Lic.YG (Yellow and grey lichens on supralittoral rock)	LR.FLR.Lic.Ver (Verrucaria Maura on littoral fringe rock)		LR.FLR.Eph (Ephermeral green or red seaweeds (Fresh water or sand influenced)
Sub Biotope			LR.FLR.Liv.VerB (Verrucaria maura and sparse barnacles on exposed littoral fringe rock)	LR.FLR.Lic.Ver.Ver (Verrucaria maura on very exposed to very sheltered upper littoral fringe rock)

Below are images of some of organisms you may encounter whilst rock pooling in these habitats:

The exposed nature of the shore leads to an extended lichen zone. Habitat classification: LR.FLR.Lic.(Lichens on supralittoral and littoral fringe rock) ENUI.11S: B3 and LR.HLR. MusB (Mussel and/or barnacle communities) EUNIS: A1.11.

A variety of grey and yellow lichens occur on the boulders within the supra littoral. Habitat classification: LR.FLR.Lic.YG (Yellow and grey lichens on supralittoral rock) EUNIS: B3.111.

Below the grey and yellow lichens the black, Tar lichen (Verrucaria maura) covers the rock . Habitat classification: LR.FLR.Lic.Ver (Verrucaria maura on litto.ral fringe rock) EUNIS: B3.113

Faunal diversity is low among the boulders  and principally constitute Verrucaria maura and periwinkles. Here a rough periwinkle (Littorina sp) seeks refuge on the underside of a boulder. Habitat classification: A variant of LR.FLR.Lic.Ver.Ver (Verrucaria maura on very exposed to sheltered upper littoral fringe rock).

A limpet, Periwinkle (Littorina sp) and sparse barnacles occur below the more barren LR.LIC.Ver.Ver. Habitat classification:A variant of  LR.FLR.Liv.VerB (Verrucaria maura and sparse barnacles on exposed littoral fringe rock) EUNIS: B3.1131

A rough periwinkle (Littorina compressa), small periwnkles (Melarhaphe neritoides) and barnacles seek refuge from wave exposure by pushing them selves up into each knock and cranny that the uneven texture of the boulder face provides.

Rough periwinkles (Littorina sp) aggregate between boulders.

A rough periwinkle (Littorina saxatilis agg.) and small periwinkles (Melarhaphe neritoides).

A rough periwinkle (Littorina compressa)

Further down the shore the Verrucaria spp occurs as patches, and barnacle and limpet abundance increase. Other species, such as dog whelk (Nucella lapillus) also occur. Habitat classification: LR.HLR. MusB (Mussel and/or barnacle communities) EUNIS: A1.11.

Limpets

On exposed shores species aggregate on the leeward side of boulders to avoid  being dislodged by wave action.

Thick topshells (Osilinus lineatus) aggregate among more sheltered boulders that are in the lee of bedrock formations.

Thick topshells (Osilinus lineatus), beadlet anemones (Actinia equina), barnacles and limpets charecterise the upper shore barnacle communities.

An encrusting red grows on a boulder.

Catenella caespitosa forms a turf  in the damp between two boulders.