Rockpooling destination: Revisit Land's End peninsular: Scour tolerant and robust fucoid/red seaweed habitats

Steep cliffs surround the bay, the lower craggy edges covered in lichens. The cliff bases and steeper bedrock transition between the lichen and barnacle communities with limpets, periwinkles and whelks. Boulders and bedrock of the mid and lower shore host a similar barnacle community plus a variety of seaweeds, including where sand scour is event, ephemeral seaweeds. Rockpools occur throughout the shore, and a river flows downs from the cliffs.

The bay experiences a dynamic regime, alternating between periods of erosion and deposition. The underlying substrate is boulders and bedrock, however, variable amounts of sand may be deposited on top, sourced from the sand bar situated offshore. The communities encountered reflect the alternation between these regimes.


The shore alternates between periods of deposition (sandy)  and erosion (stony).

April 2015

September 2013                    January 2014
The overlaying sand has been eroded to reveal the boulders beneath.

At the time of visitation the cove was comprised of boulders and bedrock with an occasional thin veneer of sand.

Habitat classification:

Substrate	LR (Littoral rock)
Habitat	LR.HLR (High energy littoral rock)	LR.MLR (Moderate energy littoral rock)		LR.FLR (Features of ilttoral rock)
Biotope complex	LR.  HLR.MusB (Mussels and/or barnacles on high energy littoral rock)	LR.MLR.BF (Barnacles and fucoids on moderately exposed shores)		LR.FLR.Lic.(Lichens on supralittoral and littoral fringe rock).	LR.FLR.Rkp (Rockpools)		LR.FLR.Eph (Ephemeral green or red seaweed communities		LR.FLR.CvoV (Littoral caves and overhangs).
Biotope		LR.MLR.BF.Fser (Fucus serratus on   moderately exposed eulittoral rock)	LR.MLR.BF.Rho (Rhodothamniella floridula on sand scoured lower eulittoral rock)	LR.FLR.Lic.Ver (Verrucaria Maura on littoral fringe rock)	LR.FLR.Rkp.Cor (Coralline crust-dominated shallow eulittoral rockpools)	LR.FLR.Rckp.SwSed (Seaweeds in sediment- floored eulittoral rockpools).	LR.FLR.Eph (Ephermeral green or red   seaweeds (Fresh water or sand influenced)	LR.FLR.Eph.EntPor (Porphyra purpurea and Entomorpha spp. on sand scoured mid to  lower eulittoral rock)
Sub Biotope		LR.MLR.BF.Fser.R (Fucus serratus and red seaweeds on moderately exposed lower eulittoral rock)			LR.FLR.Rkp.Cor.Cor (Corallina officinalis and coralline crusts in shallow eulittoral rockpools)

Below are images of organisms you may encounter whilst rockpooling among the lower shore habitats:

The influences of subtidal sand scour increases on the lower shore, influencing the species found. Sand scour tolerant  seaweeds flourish, including the red seaweed, sand binder (Rhodothamniella floridula) and the ephemeral green Cladophora spp.

Sand binder (Rhodothamniella floridula) can attain high abundance on the shore. Habitat classification: LR.MLR.BF.Rho (Rhodothamniella floridula on sand scoured lower eulittoral rock)

Among the sandbinder covered rock are rockpools filled with sand . These sediment filled rockpools support a variety of  red and ephemeral green seaweeds  including, Corallina officinalis, Ahnfeltia plicata and Lomentaria articulata.  LR.FLR.Rkp.SwSed (Seaweeds in sediment-floored eulittoral rockpools) EUNIS:A1.413.

Rhodophtya within a sand filled rockpool of the lower shore.

Rhodophtya within a sand filled rockpool of the lower shore.

Rhodophtya (Polyides rotundus) within a sand filled rockpool of the lower shore.

Ulva spp

A sea hare (Aplysiomorpha) and anemone within a sand filled rockpool of the lower shore.

The green seaweed, Bryopsis spp

A juvenile crab

Anemonia viridis

The ephemeral green seaweed, Cladophora rupestris.

Seaweed abundance within the sediment filled rockpools, especially that of ephemeral greens is not as extensive as observed in October, 2014. (See blog post  http://thesaltyscavenger.blogspot.co.uk/2015/03/rockpooling-destination-revisit-of.html )

Where sand scour is reduced  serrated wrack and red seaweeds increase in abundance to form patches among the sand binder. Habitat classification: LR.MLR.BF.Fser.R (Fucus serratus and red seaweeds on moderately exposed lower eulittoral rock) and LR.MLR.BF.Rho (Rhodothamniella floridula on sand scoured lower eulittoral rock.

 The seaweeds of  LR.MLR.BF.Fser.R (Fucus serratus and red seaweeds on moderately exposed lower eulittoral rock)  include Lomentaria articulata, Mastocarpus stellatus, Fucus serratus, Chondrus crispus, Rhodothamniella floridula and Osmundea Spp.

Grey topshell (Gibbula cineraria)

Eventually Fucus cover gives way to robust reds and Himanthalia elongata. Habitat classification: LR.HLR.FR (Robust fucoids and/or red seaweed communities) EUNIS: A1.12.

Corallina officinalis forms a turf on the bedrock with robust reds, Himanthalia elongata and Laminaria spp.

Corallina officinalis forms a turf on the bedrock.

Mastrocarpus stellatus,  Rhodothamniella floridula, Laminaria spp and Himnathlia elongata.

Osmundea spp, Corallina spp  and Himnathlia elongata.

Rhodophyta

Rhodophyta

Bifurcaria bifurcata

Chondracanthus acicularis

A turf of robust reds, dominated by Mastrocarpus stellatus,  Laminaria spp and Himnathlia elongata.

Himnathlia elongata.

Edible crab (Cancer pagurus)

Sea caves on the shore provide shade allowing species who are more sensitive to sunlight  to extend their occurrence beyond that of the rockpools. Habitat classification: LR.FLR.CvoV (Littoral caves and overhangs) EUNIS: A1.44.

Corallinaceae crusts occur within and extend beyond the rockpools of the cave entrance due to the shade provided by the overhanging cliff.

Cladophora spp and Coralinaceae crusts live in the shaded entrance of the sea cave.

Corallinaceae crusts occur within a rockpool of the cave cliff edge.

Rockpooling Destination: Revisit Lands' End Penisular, April 2015 - Ephemeral seaweeds to Fucoid and Barnacle habitats

Steep cliffs surround the bay, the lower craggy edges covered in lichens. The cliff bases and steeper bedrock transition between the lichen and barnacle communities with limpets, periwinkles and whelks. Boulders and bedrock of the mid and lower shore host a similar barnacle community plus a variety of seaweeds, including where sand scour is event, ephemeral seaweeds. Rockpools occur throughout the shore, and a river flows downs from the cliffs.

The bay experiences a dynamic regime, alternating between periods of erosion and deposition. The underlying substrate is boulders and bedrock, however, variable amounts of sand may be deposited on top, sourced from the sand bar situated offshore. The communities encountered reflect the alternation between these regimes.


The shore alternates between periods of deposition (sandy)  and erosion (stony).

April 2015

September 2013                    January 2014
The overlaying sand has been eroded to reveal the boulders beneath.

At the time of visitation the cove was comprised of boulders and bedrock with an occasional thin veneer of sand.

Habitat classification:

Substrate	LR (Littoral rock)
Habitat	LR.HLR (High energy littoral rock)	LR.MLR (Moderate energy littoral rock)		LR.FLR (Features of ilttoral rock)
Biotope complex	LR.  HLR.MusB (Mussels and/or barnacles on high energy littoral rock)	LR.MLR.BF (Barnacles and fucoids on moderately exposed shores)		LR.FLR.Lic.(Lichens on supralittoral and littoral fringe rock).	LR.FLR.Rkp (Rockpools)		LR.FLR.Eph (Ephemeral green or red seaweed communities		LR.FLR.CvoV (Littoral caves and overhangs).
Biotope		LR.MLR.BF.Fser (Fucus serratus on   moderately exposed eulittoral rock)	LR.MLR.BF.Rho (Rhodothamniella floridula on sand scoured lower eulittoral rock)	LR.FLR.Lic.Ver (Verrucaria Maura on littoral fringe rock)	LR.FLR.Rkp.Cor (Coralline crust-dominated shallow eulittoral rockpools)	LR.FLR.Rckp.SwSed (Seaweeds in sediment- floored eulittoral rockpools).	LR.FLR.Eph (Ephermeral green or red   seaweeds (Fresh water or sand influenced)	LR.FLR.Eph.EntPor (Porphyra purpurea and Entomorpha spp. on sand scoured mid to  lower eulittoral rock)
Sub Biotope		LR.MLR.BF.Fser.R (Fucus serratus and red seaweeds on moderately exposed lower eulittoral rock)			LR.FLR.Rkp.Cor.Cor (Corallina officinalis and coralline crusts in shallow eulittoral rockpools)

 Below are images of organisms you may encounter whilst rockpooling in the upper and mid shore habitats:

One year ago these boulders were covered by sand. Now uncovered they are slowly being colonized by organisms, either from neighbouring rock or from planktonic recruitment.

Boulders and rockpools of the upper to mid shore that are influenced by the fresh water run off and sand scour are characterised by ephemeral red and green seaweeds. Habitat classification: LR.FLR.Eph (Ephermeral green or red  seaweeds (Fresh water or sand influenced) EUNIS:A2.82

The ephermeral green and/or red  seaweed biotope extends over much of the upper and mid shore coinciding with the rivers flow.

Ephemeral green algae (Ulva spp - previously Entomorpha spp)

The distribution of fauna in the mid to lower shore is influenced by wave exposure, subtidal sand scour, fresh water run off and desiccation. The result is a patchwork of biotopes that are not distributed evenly down the shore. Here fucoids and barnacles cover the boulders, whilst ephemeral green algae lace the diluted pools where the river flows to the sea.  Habitat classification: LR.MLR. BF (Barnacles and fucoids on moderately exposed shores) and LR.FLR.Eph (Ephermeral green or red seaweeds (Fresh water or sand influenced). 

Unlike the upper shore the mid shore habitats appear unchanged from October, 2014 when this photograph was taken.

The fucoid and barnacle community of the  LR.MLR. BF (Barnacles and fucoids on moderately exposed shores) habitat comprises dog whelks, beadelt anemones, barnacles and red seaweeds, among other species....

Beadlet anemone (Actinia equina)

A Chiton, so highly camouflaged it could be missed among the coralline edged rock.

Gibbula umbilicus can be found between and under the boulders, where conditions are damper.

Limpets are able to withstand greater desiccation than other shore gastropods and are found all over the boulders, usually aggregated on the lee ward side.  

New fucoid growth, on a particularly sandy boulder. As the lower shore is reached the influence of subtidal sand scour increases and this influences the organisms found.

Fucus sp and a red seaweed.

Rockpooling Destination: Revisit Land's End Peninsular April 2015 - Littoral fringe, barnacle communities and coralline rockpools

Steep cliffs surround the bay, the lower craggy edges covered in lichens. The cliff bases and steeper bedrock transition between the lichen and barnacle communities with limpets, periwinkles and whelks. Boulders and bedrock of the mid and lower shore host a similar barnacle community plus a variety of seaweeds, including where sand scour is event, ephemeral seaweeds. Rockpools occur throughout the shore, and a river flows downs from the cliffs.

The bay experiences a dynamic regime, alternating between periods of erosion and deposition. The underlying substrate is boulders and bedrock, however, variable amounts of sand may be deposited on top, sourced from the sand bar situated offshore. The communities encountered reflect the alternation between these regimes.


The shore alternates between periods of deposition, sandy  and erosion, stony.

April 2015

September 2013                    January 2014
The overlaying sand has been eroded to reveal the boulders beneath.

At the time of visitation the cove was comprised of boulders and bedrock with an occasional thin veneer of sand.

Habitat classification:

Substrate	LR (Littoral rock)
Habitat	LR.HLR (High energy littoral rock)	LR.MLR (Moderate energy littoral rock)		LR.FLR (Features of ilttoral rock)
Biotope complex	LR.  HLR.MusB (Mussels and/or barnacles on high energy littoral rock)	LR.MLR.BF (Barnacles and fucoids on moderately exposed shores)		LR.FLR.Lic.(Lichens on supralittoral and littoral fringe rock).	LR.FLR.Rkp (Rockpools)		LR.FLR.Eph (Ephemeral green or red seaweed communities		LR.FLR.CvoV (Littoral caves and overhangs).
Biotope		LR.MLR.BF.Fser (Fucus serratus on   moderately exposed eulittoral rock)	LR.MLR.BF.Rho (Rhodothamniella floridula on sand scoured lower eulittoral rock)	LR.FLR.Lic.Ver (Verrucaria Maura on littoral fringe rock)	LR.FLR.Rkp.Cor (Coralline crust-dominated shallow eulittoral rockpools)	LR.FLR.Rckp.SwSed (Seaweeds in sediment- floored eulittoral rockpools).	LR.FLR.Eph (Ephermeral green or red   seaweeds (Fresh water or sand influenced)	LR.FLR.Eph.EntPor (Porphyra purpurea and Entomorpha spp. on sand scoured mid to  lower eulittoral rock)
Sub Biotope		LR.MLR.BF.Fser.R (Fucus serratus and red seaweeds on moderately exposed lower eulittoral rock)			LR.FLR.Rkp.Cor.Cor (Corallina officinalis and coralline crusts in shallow eulittoral rockpools)

Bedrock and boulders of the upper shore. A year ago theses were covered by sand, now they are slowly being colonized by fauna, many of whom appear to have moved down from the previously bare rock. Small periwinkles (Melarhaphe neritoides), Rough periwinkles (Littorina sp) and limpets occur on bedrock outcrops, whilst rockpools and boulders are becoming colonised by ephemeral greens.

The assignment of habitats to such shores can be difficult as the species present represent transitional communities that have not yet attained a stable species/ abundance relationship upon which classical biotope classification systems are based. This highlights the importance of long term monitoring of shores when conducting phase 1 habitat surveys, as the habitats found can change.

Below are images of organisms you may encounter whilst rockpooling within the littoral fringe and upper to mid shore habitats:

These photographs show the increase in ephemeral green algae cover on rocks between October 2014 and April 2015. 

Periwinkles occur on the shore and are one of the most prominent mobile fauna of the littoral fringe and upper shore.

Melarhaphe neritoides

Littorina spp and M. neritoides and sparse barnacles on the littoral fringe cliff edge.

Rough periwinkles (Littorina spp) and limpets (Patella vulgata) have begun to recolonise upper shore boulders that were previously covered by sand.

Similarly upper shore bed rock is being recolonised by limpets (Patella vulgata)

The cliff bases enable organisms to move up and down in response to the sediment regime and sand scour, as a result they support more stable barnacle communities with limpets, periwinkles, mussels and whelks. In the case of limpets the spray from the waves of this high energy shore, enable them to live far up the cliff base.Habitat classification: LR.HLR.MusB (Mussels and/or barnacles on high energy littoral rock) EUNIS: A1.11.

The base of the cliffs are hollowed by the grinding of the boulders. An indication of the high wave exposure experienced by organisms on this shore.



Barnacles and small periwinkles (Melarhaphe neritoides) cover the bases of the cliffs.

The cliff bases hold a number of small coralline rockpools that support corallinaceae crusts, limpets and red seaweeds. Habitat classification: LR.FLR.Rkp.Cor (Coralline crust-dominated shallow eulittoral rockpools) EUNIS: A1.411

A coralline rockpool with red seaweeds and limpets.

The distribution of fauna in the upper and mid shore is influenced by wave exposure, subtidal sand scour, fresh water runoff and desiccation.  Where the upper shore is not influenced by fresh water run off, barnacle communities similar to that of the cliff bases cover the boulders. Habitat classification: LR.HLR.MusB (Mussels and/or barnacles on high energy littoral rock) EUNIS: A1.11. 

Barnacles

Barnacles

A limpet (Patella spp)

A limpet (Patella spp)

Barnacles and Littorina compressa var. nigrolineata.

Dog whelks (Nucella lapillus), Limpets (Patella spp) and barnacles.

Barnacles and Patella depressa

Verrucaria mucosa

Some boulders are smooth and uncolonised by fauna.