Tuesday 27 January 2015

Rockpooling Destination: Hemsby, January 2015

A strandline dominated by hornwrack still occurs on the shore but now several new things are beginning to be washed up in the strandline too. 

The most interesting are the mermaids' purses; months before skates, rays and catfish (formally dogfish) laid their egg cases among the cobbles and bryozoans and within these egg cases the embryos developed into miniature adults. As they became too large for their egg cases they broke free and the discarded egg cases drifted with the waves and currents until finally, they were washed up on the shore.

If you find a mermaids' purse why not report your sighting to the shark trust great egg case hunt?. You can find out more about submitting sightings and about rays and sharks at 
http://www.sharktrust.org/en/great_eggcase_hunt


The sandy shore with a strandline dominated by the remains of the bryozoan, hornwrack (Flustra foliacea). Habitat classification: LS.LSa.St (Strandline) and LS.LSa (Littoral sand).


The sandy shore with a strandline dominated by the remains of the bryozoan, hornwrack (Flustra foliacea)



A small spotted catshark (Scyliorhinus canicula) egg case.


A Thornback (Raja clavata) egg case


A spotted ray  (Raja montagui) egg case.

This was one of two, grey seal pups washed up on the shore that day. 

Saturday 24 January 2015

Hemsby, January 2015

Winter storms have washed up quantities of hornwrack (Flustra foliacea) onto the sandy shore at Hemsby, Norfolk.


Many different things can be found among the washed up hornwrack, including the remains of crabs, sponges, razor shells and slipper limpets.

The sandy shore with successive strandlines dominated by the remains of the bryozoan, hornwrack (Flustra foliacea). Habitat classification: LS.LSa.St (Strandline) and LS.LSa (Littoral sand).

Hornwrack (Flustra foliacea)

The remains of Hornwrack (Flustra foliacea), crabs and seaweeds comprise the strandline.

Tuesday 13 January 2015

Lerwick, September 2014 - Upper mid shore to lower shore..

The exposed to moderately exposed shore is comprised of sloping bed rock and boulders with crevices, gullies and rockpools. There is freshwater influx from a small waterfall at the base of the cliffs.

Lichens characterise the supralittoral and littoral fringe. Whilst limpets and sparse barnacles charecterise the upper shore with periwinkles throughout both the littoral fringe and upper shore (See previous post).

Rockpools occur from the upper shore down. The majority of which are encrusted with corallinaceae crusts. These coralline rockpools support a variety of fauna depending on their relative size, exposure and position on the shore (See previous post).

Above the rockpools the rock of the upper mid to lower shore is covered in varying abundances of fucoids and barnacles with an array of other organisms within the rock crevices.


Habitat classification: 

Substrate
LR (Littoral rock)
Habitat
LR.MLR (Moderate energy littoral rock)
LR.FLR (Features of ilttoral rock)
Biotope complex
LR.MLR.BF (Barnacles and fucoids on moderately exposed shores)
LR.FLR.Rkp (Rockpools)
Biotope
LR.MLR.BF.FspiB (Fucus spiralis on full salinity exposed to moderately exposed upper eulittoral rock)
LR.MLR.BF.Fser (Fucus serratus on moderately exposed eulittoral rock)
LR.FLR.Rkp.Cor (Coralline crust dominated shallow eulittoral rockpools)
LR.FLR.Rkp.FK (Fucoids and Kelp in deep eulittoral rockpools)
Sub biotope


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 these habitats:


The shore is comprised of sloping bed rock and boulders with crevices, gullies and rockpools.

Fucoids and barnacles form a patchwork across the shore interspersed with rockpools. Habitat classification: LR.MLR.BF (Barnacles and fucoids on moderately exposed shores).

Fucus spiralis occurs in the upper mid shore. Habitat classification: LR.MLR.BF.FspiB (Fucus spiralis on full salinity exposed to moderately exposed upper eulittoral rock)

A dog whelk (Nucella laupillus).


An edible periwinkle (Littorina littorea).




Small individuals of common mussel (Mytilus edulis) occur within crevices.



The damp crevices support a variety of organisms including Cladophora sp and limpets.
Coral weed (Corallina officinalis) overgrows corallinaceae crust in a damp crevice of the shore, surrounded by limpets and barnacles.

A variant of coral weed grows on a limpet.

A sprintail on the shore.



Barnacles and limpets (Patella vulgata)


P. vulgata seek refuge amongst F. spiralis


Nucella lapillus

Clumps of F. spiralis amongst barnacles and Nucella lapillus. Barnacle density is increased in this section of the shore; and they constitute the major diet of the dog whelks.
Clumps of F. spiralis amongst barnacles and Nucella lapillus

Clumps of F. spiralis amongst barnacles and Nucella lapillus
Beadlet anemones (Actinia equina), barnacles and Nucella lapillus

A beadlet anemone (Actinia equina)


Small individuals of M. edulis grow amongst the barnacles.
Small individuals of M. edulis grow amongst the barnacles.
Different sized barnacles represent different cohorts amongst the shore from separate recruitment episodes.


Serrated wrack (Fucus serratus) and Thong weed (Himanthalia elongata) occur on the lower shore. Habitat classification: LR.MLR.BF.Fser (Fucus serratus on moderately exposed eulittoral rock)

Young Fucus serratus, thongweed (Himanthalia elongata)and barnacles on the lower shore.

Young growth of Fucus sp.

Seaweed diversity increases down the shore.



Thongweed (Himanthalia elongata)


Osmundea sp
A flat periwinkle (Littorina sp) on the lower shore.















































































Friday 9 January 2015

Lerwick, Shetland September 2014 - Rockpools

The exposed to moderately exposed shore is comprised of sloping bed rock and boulders with crevices, gullies and rockpools. There is freshwater influx from a small waterfall at the base of the cliffs.

Lichens characterise the supralittoral and littoral fringe. Whilst limpets and sparse barnacles charecterise the upper shore with periwinkles throughout both the littoral fringe and upper shore (See previous post).

Rockpools occur from the upper shore down. The majority of which are encrusted with corallinaceae crusts. These coralline rockpools support a variety of fauna depending on their relative size, exposure and position on the shore.

Habitat classification: 
Substrate
LR (Littoral rock)
Habitat
LR.FLR (Features of ilttoral rock)
Biotope complex
LR.FLR.Rkp (Rockpools)
LR.FLR.Lic.(Lichens on supralittoral and littoral fringe rock).
Biotope
LR.FLR.Rkp.Cor (Coralline crust dominated shallow eulittoral rockpools)
LR.FLR.Rkp.FK (Fucoids and Kelp in deep eulittoral rockpools)
LR.FLR.Lic.Ver (Verrucaria Maura on littoral fringe rock)
LR.FLR.Lic.YG (Yellow and grey lichens on supralittoral rock)
Sub biotope
LR.FLR.Rkp.Cor.Cor (Corallina officinalis and coralline crusts in shallow eulittoral rockpools)






The shore is comprised of sloping bed rock and boulders with crevices, gullies and rockpools.
A shallow coralline rockpool covered in corallinaceae crust. Habitat classification: LR.FLR.Rkp.Cor (Coralline crust dominated shallow eulittoral rockpools).


Coralline rockpools come in a variety of forms and larger pools tend to support more species.
The coralline rockpools are extensive in the mid and lower shore and support and increased variety of  seaweed species, including  clumps of  Coral weed (Corallina officinalis). Habitat classification: LR.FLR.Rkp.Cor.Cor (Coralline crusts and Corallina officinalis in shallow eulittoral rockpools).

A variety of seaweed species can be found  within the coralline rockpools, especially in the summer months. The seaweeds comprise a variety of reds plus ephemeral greens.
The most obvious seaweed is the encrusting corallinaceae crusts that make the rockpool look like it has been covered in pink paint.

The other charecteristic seaweed to be found within the rockpools is coral weed (Corallina officinalis).
C.officinalis can form turfs on the sides and bottom of the rockpools.
C.officinalis grows on top of the corallinaceae crust.

A variety of red seaweeds also occur within the coralline rockpools.





Ceranium sp


Codium sp
A number of gastropod species occur within the coralline rockpools. Including edible periwinkles (Littorina littorea) and limpets.
Edible periwinkles (Littorina littorea) and limpet within a coralline rockpool.


The 'home' scar left by a limpet


Barnacles also occur in some rockpools and look as if they almost 'erupt' from the corallinaceae crust.


Barnacles amongst corallinaceae crust


On the lower shore sugar kelp (Saccharina latissima) begins to occur within the deeper rockpools.  Habitat classification: LR.FLR.Rkp.FK (Fucoids and Kelp in deep eulittoral rockpools).


Saccharina latissima occurs within deeper rockpools.

Serrated wrack (Fucus serratus) and Thong weed (Himanthalia elongata) also occur in the deeper lower shore rockpools.

Fucus serratus


Breadcrumb sponge (Halichondria (Halichondria) panicea) occurs within the deepest pools near the low tide mark.