Category: Seaweeds
Watery Embrace
Underwater
I love how the sunlight sparkles and shimmers within the rippling movement of the waters on the coast. These are abstract worlds which I would like to glimpse more often than I do, full of the richness of life and wonder. These images feature what I believe is a seaweed called Gutweed (Ulva intestinalis).
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Shanklin Beach, Isle of White, England, August 2018 © Pete Hillman.
Discoveries In The Rockpool #2
Discoveries In The Rockpool
Washed Up
Spiral Wrack Fucus spiralis
Coral Weed
Corallina officinalis
This seaweed has a feathery appearance with its regular, opposing branched pattern. It varies in colour due to age and lighting conditions. The deeper it is it grows dark pink. It has a pink, disc-shaped encrusting holdfast which helps it anchor itself to rocks, shells or other larger seaweeds. It can grow up to 12cm in height.
It is typically found lining the edges of mid-shore rock pools. It is common and widespread.
Photographs of Coral Weed (Corallina officinalis), taken August 2015, in rock pool Meadfoot Beach, Torquay, Devon. © Pete Hillman 2015. Camera used Nikon D3200, with Sigma 105mm macro lens.
Prasiola stipitata
This is a small, dark green lettuce-like algae when wet, which forms flaky coatings over rocks and boulders. Length 1cm.
It grows on rocks and stones in the splash zone, mostly frequented by seabirds which drop their faeces from which it gets its nitrates to flourish. A common and widespread species, but mainly seen in spring and early summer.
Photographs of Prasiola stipitata taken April 2013, Llandudno, Wales. © Pete Hillman 2013. Camera used Nikon Coolpix P500.
Purple Laver
Porphyra umbilicalis
Greenish in colour when young, but becoming purple-red as it matures, and is very resistant to drying out and the action of the waves. It forms thin, delicate sheets which cling to rocks and has a polythene-like texture. Width 20cm.
Found attached to rocks in sandy habitats. Abundant and widespread on rocky shores throughout.
Purple Laver is used to make laverbread in Wales, which is a traditional Welsh recipe.
Photographs of Purple Laver (Porphyra umbilicalis) taken April 2013, Llandudno, Wales. © Pete Hillman 2013. Camera used Nikon Coolpix P500.
Sea Belt
Saccharina latissima
Also called ‘Sugar Kelp’ or ‘Poor Man’s Weatherglass’, this is a long, belt-like brown to olive coloured seaweed with wavy edges and a crinkled centre. Length 4cm.
It grows in deep pools and around the low tide mark, usually on sheltered rocky shores attached to rocks with a small branching holdfast. A common and widespread species.
Photographs of Sea Belt (Saccharina latissima), taken August 2015, in rock pool Meadfoot Beach, Torquay, Devon. © Pete Hillman 2015. Camera used Nikon D3200, with Sigma 105mm macro lens.
Egg Wrack Wool
Polysiphonia lanosa
A brownish-red seaweed which is tufted and made up of branching filaments which gives it a wool-like consistancy. Length 70cm.
Found middle to low shore, and grows mainly on Egg Wrack (Ascophyllum nodosum) for physical support, known as an epiphyte. It makes use of the hosts buoyancy at high tide so it will gain more sunlight. Common and widespread throughout the British coastline.
Photographs of Egg Wrack Wool (Polysiphonia lanosa), taken August 2015, in rock pool Meadfoot Beach, Torquay, Devon. © Pete Hillman 2015. Camera used Nikon D3200, with Sigma 105mm macro lens.
Toothed Wrack
Fucus serratus
Also called “Saw Wrack’ or ‘Serrated Wrack’, this is an olive to golden brown seaweed, flattened with a prominant midrib and saw-toothed fronds. Length 60cm. Frond width 2cm.
Found on the lower zone, it latches onto rocks on more sheltered shores. A common and widespread species.
Photographs of Toothed Wrack (Fucus serratus), taken August 2015, in rock pool Meadfoot Beach, Torquay, Devon. © Pete Hillman 2015. Camera used Nikon D3200, with Sigma 105mm macro lens.
Spiral Wrack
Fucus spiralis
Also called ‘Flat Wrack’, it is a dark olive-brown or greenish seaweed with a prominent midrib with no gas bladders. There are often pairs of swollen reproductive bodies on the tips of the frond branches. The fronds have a tendency to twist. Length 15 to 20cm.
Occurring on the upper shore, preferring sheltered to moderately exposed shores, where they cling to the hard surfaces. It also extends well into estuaries. It reproduces from July to September. A common and widespread species.
Photograph of Spiral Wrack (Fucus spiralis) taken June 2012, Llandudno, Wales. © Pete Hillman 2012. Camera used Nikon Coolpix P500.
Channelled Wrack
Pelvetia canaliculata
This seaweed is dark greenish-brown in colour when dry and yellow when wet. It has no gas bladders, the fronds have no midribs, and they are curled along the length forming a channel. Height 15cm.
Found on the upper shore attached to rocks. Reproduces from August to September. It is very resiliant to desiccation, and can survive for up to eight days without water. A common and widespread species.
Photograph of Channelled Wrack (Pelvetia canaliculata) taken June 2012, Llandudno, Wales. © Pete Hillman 2012. Camera used Nikon Coolpix P500.
Egg Wrack
Ascophyllum nodosum
Also called ‘Knotted Wrack’, this is a yellowish to olive-green seaweed, which has long, narrow chain-like fronds with gas-filled bladders. This is a slow-growing seaweed which has no mid-rib. Height 0.5 to 2m.
Found on rocky shores, often on the mid-shore, preferring sheltered conditions, extending into estuaries and usually attached to rocks. It reproduces April to June. Egg Wrack Wool (Polysiphonia lanosa) is commonly found attached to it in clumps. A common and widespread species.
Photograph of Egg Wrack (Ascophyllum nodosum) taken June 2012, Llandudno, Wales. © Pete Hillman 2012. Camera used Nikon Coolpix P500.
Gutweed
Ulva intestinalis
This aptly named bright grass green seaweed forms an inflated, tube-like frond which resembles an intestine. Length up to 80cm.
Found attached to rocks and stones on sandy or muddy shores, in sheltered estuaries and rock pools on the upper shore. A common and widespread species.
Photographs taken April 2013, Llandudno, Wales, and August 2015, Meadfoot Beach, Torquay, Devon.
Sea Lettuce
Ulva lactuca
A pale to dark green seaweed, which has no midrib. It has wavy edges and translucent green fronds. Length 40cm.
The Sea Lettuce is tolerant of most conditions, except extreme exposure. It is found throughout the intertidal zone on rocky shores, estuaries, and free-floating. It may also be discovered attached to rocks or stones in rockpools. A common and widespread species.
Photographs taken June 2012, Llandudno, Wales, and August 2015, Meadfoot Beach, Torquay, Devon.