Terrestrial predators in the intertidal zone

The intertidal zone is not isolated from the terrestrial environment. In particular there are a number of predators and grazers that feed in the intertidal and shallow marine environment. 

Below are images of such examples:

  On the tops of the low cliffs that flank rocky shores in Shetland, an assortment of marine organisms’ remains scatter the ground. These are the remains of terrestrial predation of the intertidal zone.

Sanderlings feed amongst the strand line

Shetland ponies come down on to the shore to graze on the washed up seaweed.

Rockpooling destination: Unst, Shetland, September 2014

The rocky shore comprises shelving bedrock with crevices and small rock pools.

 Tar lichen occurs in the littoral fringe and extends as patches into the upper shore (supralittoral) with periwinkles. The upper and mid shore are charecterised by barnacles and limpets with the addition of mussels in the mid shore; whilst spiral wrack occurs on the sheltered aspects of the rock and red seaweeds occur across the lower shore.

Habitat classification:

Substrate	LR (Littoral rock)
Habitat	LR.HLR (High energy littoral rock)	FLR (Features of littoral rock)
Biotope complex	LR.HLR. MusB (Mussel and/or barnacle communities)	LR.FLR.Lic (Lichens on supralittoral rock)	LR.FLR.Rkp (Rockpools)	Eph.FLR.Eph (Ephemeral green or red seaweed communities
Biotope		LR.FLR.Lic.Ver (Verrucaria maura on littoral fringe rock)	LR.FLR.Rkp.Cor (Coralline crust dominated shallow eulittoral rockpools)	LR.FLR.Eph.EntPor (Porphyra purpurea and Entomorpha spp. on sand scoured lower eulittoral rock)

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

   The rocky shore comprises sloping bed rock with crevices and rockpools. Tar lichen (Verrucaria maura) and rough periwinkles (Littorina sp) occur in the supralittoral, rockpools, barnacles, limpets and barnacles occur throughout the upper, mid and lower shore. Whilst mussels occur with crevices of the mid shore. Spiral wrack (Fucus spiralis) is confined to the sheltered sides of the rock and red occur throughout the mid and lower shore. Habitat classification: LR.FLR.Lic.Ver (Verrucaria maura on littoral fringe rock), LR.FLR.Rkp.Cor (Coralline crust dominated shallow eulittoral rockpools) and LR.HLR. MusB (Mussel and/or barnacle communities.

  Small periwinkles (Melarhaphe neritoides) and both species of rough periwinkle (Littorina sp) occur with tar lichen (Verrucaria maura) within the littoral fringe. Habitat classification:  LR.FLR.Lic.Ver (Verrucaria maura on littoral fringe rock).

Barnacles and limpets occur across the shore (Eulittoral) with small coralline rockpools scattered throughout. Habitat classification: LR.FLR.Rkp.Cor (Coralline crust dominated shallow eulittoral rockpools) and LR.HLR. MusB (Mussel and/or barnacle communities.

    A small coralline rockpool of the mid shore with a small encrustation of corallinacea crusts, Limpets (Patella sp) and Beadlet anemones (Actinia equina).

Coral weed (Corallina officinalis), Corallinaceae crust, barnacles and epiphytic seaweed within a coralline rockpool

   Limpets (Patella vulgata) and sparse barnacles.

  Limpets (Patella vulgata), barnacles and a red seaweed.

Common blue mussels (Mytilus edulis) occur within crevices amongst barnacles and limpets (Patella sp) of the mid shore. Habitat classification: LR.HLR. MusB (Mussel and/or barnacle communities.

   M. edulis occur within crevices amongst barnacles, limpets (Patella sp) and the red seaweed, Porphya sp.

   Barnacles, M. edulis and periwinkles.

  M. edulis, barnacles and limpets (Patella sp).

1  Further down the shore Barnacles, M. edulis forms clumps overgrown with red seaweed and dog whelks (Nucella lapillus) and periwinkles. 

   Dulse on the lower shore

Dulse on the lower shore

Dulse on the lower shore

    A red seaweed and springtails on the mid shore

  Mastocarpus stellatus, Porphyra sp and Ulva sp on the lower shore

   Fucus spiralis and Ulva sp (previously Entomorpha sp) in a sheltered area of the shore

     F. spiralis in a more sheltered area of the shore

  Cladophora rupestris and F. spiralis

  Ephemeral greens cover the lower shore boulders. Habitat classification: LR.FLR.Eph.EntPor (Porphyra purpurea and Entomorpha spp. on sand scoured lower eulittoral rock).

Rockpooling destination: North Shetland, September 2014

The shore comprised of pebbles, cobbles and boulders slopes gently to the low water mark and is positioned within a sheltered inlet on the Northern extend of Shetland main land.

The upper most shore shore is characterised by lichens and succulent plants with a strandline of washed up seaweed and debris. Channel wrack forms a band in the upper shore before a blanket of fucoids come to cover the mid and lower shore.

Habitat classification:

Substrate	LR (Littoral rock)
Habitat	LLR (Low energy littoral rock)			FLR (Features of littoral rock)
Biotope complex	LR.LLR.F (Fucoids on sheltered marine shores)			LR.FLR.Lic (Lichens on supralittoral rock)
Biotope	LR.LLR.F.Asc (Ascophyllum nodosum on sheltered mid eulittoral rock).	LR.LLR.F.Pel (Pelvetia canaliculata on sheletered littoral fringe rock)	(Fucus spiralis on moderately exposed to very sheltered upper eulittoral rock)	LR.FLR.Lic.YG (Yellow and grey lichens on supralittoral rock)	LR.FLR.Lic.Ver (Verrucaria maura on littoral fringe rock)

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

    The shore comprises relatively stable pebbles, cobbles and boulders within a sheltered inlet .Habitat classification: LR.LLR (Low energy littoral rock).

  In the splash zone ‘supralittoral’ yellow and grey lichens occur amongst the black lichen, Verrucaria maura. A red succulent plant also occurs amongst the crevices. Habitat classification: LR.FLR.Lic.YG (Yellow and grey lichens on supralittoral rock).

    Channel wrack (Pelvetia canaliculata) occurs as a band amongst Verrucaria maura in the upper shore. Habitat classification: LR.LLR.F.Pel (Pelvetia canaliculata on sheltered littoral fringe rock)

 New growth of P. canaliculata.

Spiral wrack (Fucus spiralis) with the occasional P. canaliculata occur below the main band of P. canaliculata of the upper shore. Habitat classification: LR.LLR.F.Fspi (Fucus spiralis on moderately exposed to very sheltered upper eulittoral rock) 

A barnacle

    New growth of F. spiralis

F. spiralis, Bladder wrack (Fucus vesiculosus) and Egg wrack (Ascophyllum nodosum).

  Egg wrack (A. nodosum) dominates the mid shore. Habitat classification: LR.LLR.F.Asc (Ascophyllum nodosum on sheltered mid eulittoral rock).

    Beneath the A. nodosum are limpets (Patella vulgata) and barnacles.

   Limpets, dog whelks (Nucella lapillus), edible periwinkles (Littorina littorea) and spirorbid polychaetes occur on boulders beneath the fucoid under storey.

   A limpet covered in spirorbid polychaetes.

  Edible periwinkles (Littorina littorea)

A flat periwinkle (Littorina sp.)

Ulva sp grows on the less stable mixed substrata.

  The surrounding edges of the inlet are comprised of a higher component of cobbles and boulders. Habitat classification: LR.LLR (Low energy littoral rock).

Rockpooling destination: South-west Shetland, September 2014

The large South-Westerly facing sandy bay is flanked by rocky headlands and is relatively barren of life. That which does occur is concentrated around the strandline.

Habitat classification:

Substrate	LS (Littoral substrate)
Habitat	LS.LSa (Littoral sand)
Biotope complex	LS.LSa.Mo.Sa(Barren and amphipod dominated mobile sand shores)	LS.LSa.St (Strandline)
Biotope:		LS.Lsa.St.Tal (Talitrids on the upper shore and strand-line)

Below are images of some of the organisms you may encounter in this habitat:

   The shore is comprised of mobile barren sand with strandlines at the successive tide marks. Habitat classification: LS.LSa.Mo.Sa(Barren and amphipod dominated mobile sand shores) and LS.LSa.St (Strandline).

    Clean mobile sand with amphipod burrows extend over vast expanses of the shore. Habitat classification: LS.LSa.Mo.Sa(Barren and amphipod dominated mobile sand shores).

    During the autumn migration many wades come to feed on sandy shores and amongst strandlines. Here the evidence of such feeding can be seen.

Fresh seaweed and jelly fish are washed up to form the strandline, among which the burrows of talitrids occur. Habitat classification: LS.Lsa.St.Tal (Talitrids on the upper shore and strand-line).

Jelly fish are washed up in the strandline during the summer months.

Strong waves wash up kelp (Laminaria sp) from the subtidal; on the kelps stipe and holdfast is a community of epiphytic organisms, including bivalves, red seaweeds, bryozoans and polychaetes.

Laminaria sp with a stipe covered by a variety of red seaweeds.

Laminaria sp with a stipe covered by a variety of red seaweeds and bryozoans.

Furbellows (Saccorhiza polyschides)

Sugar kelp (Saccharina latissima)

Thong weed (Himanthalia elongata)

Egg wrack (Ascophyllum nodosum) covered in bryozoa, blue common mussels (Mytilus edulis).

Egg wrack (Ascophyllum nodosum) covered in bryozoa, blue common mussels (Mytilus edulis).

Egg wrack (Ascophyllum nodosum) covered in bryozoa, blue common mussels (Mytilus edulis).

Egg wrack (Ascophyllum nodosum) covered in bryozoa.

Egg wrack (Ascophyllum nodosum) covered in bryozoan with a goose barnacle.