Carol's Cornwall
A Photographic  Library dedicated to
the Wildlife and Landscape of Cornwall

On the Beach (Algal Bloom Event St. Austell Bay August 2009)


Observations by David Fenwick 14.08.09, text taken with permission
from
A Photo Fauna of the Devon and Cornwall Peninsula.

The Status of Rockpools at Spit Point, Par, Cornwall.
Had a very sad afternoon, although the afternoon began very promising despite what had been forecast on the news. On venturing onto the beach at Spit Point there were no obvious signs of washed up fish or anything and the first uppershore rockpools I checked were teaming with small fry and other life, however this didn't last long and it wasn't long before I started to find dead gobies.

On looking in upper-middleshore pools things got a lot worse and Green Sea-Urchin were laying on the bottom of pools somewhat lifeless (usually they are all under rocks), along with various species of marine worms, some of the worms had a little bit of life left in them. I felt that if it was a warm day then most things would have been finished off completely.

The next thing that stood out a mile was that Common Periwrinkles weren't where they usually occur, they had come out of the pools and were frequenting, and grouped, or should I say clumped on rocky peaks, well out of the water, and by the thousand.

Going down to the middleshore I found large numbers of empty limpets, which was
unusual, they were just all over the place. The shells were very clean and it looked like the insides had all been eaten by seabirds as guano was frequently found around them. Birds seen in the area included Herring Gull, Oystercatcher and
Turnstones. I decided to kick a few limpets off the rocks to see how well they were attached, they came off with little effort and even large limpets could be pulled off the rocks by hand. The whole limpet colony there was obviously very stressed and being predated by the score.


Dead Sandeels and Two-spotted Gobies were common place and I also came across a dead 3lb Ballan Wrasse in the large uppershore pools. Towards Par Dock Breakwater the uppershore was stinking of hydrogen sulphide and especially where small mussel colonies ventured into some of the smaller pools. Here there was also a film and foam on the pools.

On venturing back I took images of near lifeless Snakelock Anemones, dead crabs and images of the colour of the water at low water mark, which was quite dark and murky. On walking back to the shore I noticed hundreds of seagulls and many cormorants on the rocks between Spit Point and Fisherman's Point at Baker's Beach, and presumed that there could be fish washing up there. This was confirmed by someone on the beach who had been to Baker's Beach yesterday and reported that hundreds of fish had been washing up there.

Overall, it was a very saddening experience. Last month I sent a very impressive
species list to Marlin that covered this area and I was really looking forward to having a good autumn's rockpooling season as well. If the weather warms up and the winds stay slight I fear the worst for this area and feel many species will be under threat and the area take some time to recover.


The status of Par Beach, Cornwall.
I decided to visit Par Beach after Spit Point and to see what was happening there. The first thing I saw was thousands of Sea Potatoes washed together just below the high water mark. Dead Sea Potatoes were common place all down the beach. I then noticed that there was an increase in the amount of Common Cockles on the surface of the sand. Then came a real shock, thousands of half-dead and dead lugworm all across the beach, many had been speared by beaks of seabirds, thousands must have already been eaten. Many dead flatfish were seen, the most common were plaice, a brill was also found, but no sole as per news reports, they numbered about a dozen. Other dead fish species included a few sandeels, gobies and a young conger eel of some 70cm in length.

A yellowish-brown scum could be found all over the beach in lines below the high tide mark down to low water. Hundreds of seabirds were also in the area these included Herring Gull, Black-headed Gull and Crow.

About Marine Algal Blooms
Ref: A Carrick Council statement on the algae bloom.

Marine algal blooms are natural phenomena. A 'Red Tide' is one of many such types which can appear in the oceans and seas at this time of year, although other colours are often seen instead. Under certain conditions, such as warm, sunny weather it can form huge blooms, which can be miles across. It is called a 'Red Tide' because it turns the sea a red-brown colour.

This algae can sometimes be harmful to the environment because it can deplete oxygen levels in the sea, making it difficult for fish, and other animals to breathe. It can also produce a toxin which can kill fish and other marine life. These blooms can last for some time, but will eventually disperse naturally. The algae identified so far is "Karenia mikimotoi" (previously called Gymnodium mikimotoi). This particular algae generates a toxin which is potentially harmful to shellfish, but causes more harm by removing oxygen from the water, effectively suffocating other animals such as fish and worms.

Images of the Event and its effect on Wildlife in the Area

Sit Point
Effect on Marine Worms
Relocation of Common Periwrinkles     close-up
Dead Ballan Wrasse     head
Surveying the Damage


Par Beach
Mass stranding of dead Sea Potatoes     close-up
Young Dead Conger Eel
Dead Plaice
Lugworms - driven to surface     close-up
Lugworm - speared by birds
Other effected worm species
Common Cockles on surface
Seabirds flocking to feed on carrion
Foam washed up across beach     close-up

For more images visit the Algal Bloom page of
A Photo Fauna of the Devon and Cornwall Peninsula


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