Sea Shore Exploration in Winter
- Written by David Rees
Winter can be a great time to explore the beaches as every walk can bring new discoveries. Winter is when the seaweeds are thrown ashore. It is perhaps nature’s way of preparing the next line of sand dunes as tons of seaweed is thrown high up the beach and becomes buried in the sand to act as compost for the forward march of dune plants which will hold a wall of sand together against next year’s seas.
In other areas of coastline the opposite occurs as the sea gnaws away at the towering cliffs of soft limestone rock. Great chunks fall away exposing nature’s ancient history book: fossils bedded in strata of thousands of years, giving us a glimpse of the Algarve coastline millions of years ago.
But let’s look again briefly into rock pools. Amongst the seaweeds, anemones can be seen. The largest and most common is the Golden Anemone with its purple-tipped tentacles ready to pull in any passing morsel of food. The little Beadlet Anemone, pinky red in colour, can also be found along with the green Snakelocks Anemone which cannot retract its tentacles like other anemones. Similar to the anemones, but living in muddy sand areas, is the beautiful Peacock Worm with its fans of brown or purple tentacles. The body is a tube, deep in the sand, and is impossible to remove without causing damage. Peacock Worms are plentiful in the Alvor estuary.
Wherever you find Peacock Worms there is a good chance of discovering a Ribbon Worm. They hide in the mud at low tide and can be dug our or else are found swimming amongst rocks and weed in sheltered areas. It is incredibly elastic, being able to stretch itself to over twice its ordinary size.
Jellyfish, which belong to the same group as anemones, are sometimes washed up onto the shore in winter. The common jellyfish is white and has no true tentacles unlike its relative, the Portuguese Man-of-War, which is also washed onto the beaches at times, but its blue tentacles, reaching up to an amazing 30 metres in length, should not be touched. Even when the Portuguese Man-of-War is dead, its tentacles still pack a dangerous sting.
Starfish are not very numerous in the Algarve rock pools although several species do live there. One of the easiest to see is the Spiny Starfish which lives in the rocks along the pier at Praia da Rocha. It has stiff, very spiny arms on a pale grey body with spots of blue.
Up on the sand, seaweed make an interesting area of study. There are three main groups: Green Seaweed, Brown Seaweed, and Red Seaweed. Of the Green Seaweed, look out for Codium dichotomum, with dark green felt-like fingers, looking rather like a green fingered coral. Palmophyllum crassum is a fan-shaped scallop folded beautifully into concentric waves. Sea Lettuce is immediately obvious and strings of weed looking like intestines are Enteromorpha intestinalis. Of the Brown Seaweed you can easily find Colpomenia sinuosa – a hollow knobbly ball of brown, or look for the Peacock’s Tail Seaweed – resembling a ringed trumpet.
Many Red Seaweed wash up including Peyssonnelia squamania – delicate thin lobes, leaf-like, with rings of darker red. The Corrallinaceae family form pink mats on top of bounders and rocks along the seashore.
Whilst looking for seaweed, one could also be collecting the various shells which are thrown up by the tide. Topshells, Limpets, Towershells, Cowries, Bubbleshells and the spiny Murex make up a few of the ‘single’ shells, but look also for Mussels, Scallops, Oysters, Cockles, Razorshells and the large Venus Shell, all of which are double shells or bivalves.
The most important thing to remember once you start collecting is that those with the best collections are usually those who are up earliest on the beach in the morning, exploring the least populated areas of coastline. If you find that all the best shells have been collected already, then turn your attention to the cliffs. The Algarve boasts a magnificient display of fossils right down the coastline. The cliffs are mostly limestone and sandstone and hence it is easy work to chip out fossils from the cliffs or from fallen boulders.
Small versions of the Sand Dollar still exist in America, while here their fossil remains can be anything up to 20 cm across. The Sand Dollar, being quite a large fossil bedded in the soft limestone, requires careful work to remove it whole from the cliff.Here’s how to do it. Chip away beneath and at the sides of the fossil protruding from the rock using a cold chisel and hammer. Once you have dug out the rock from beneath and from the sides, try to ease the fossil down from above. Once your fossil is out, then the cleaning work begins. Drip or paint molten wax onto any parts of the fossil that are exposed and brush on Muriatic acid (available from most hardware stores) to the areas still covered in limestone. It is best to wear gloves, of course, during the cleaning process, and work outdoors or in the garage. The Muriatic acid will quickly eat away the limestone, exposing the fossil. The fossil itself is also made of limestone, though harder and more resistant than the limestone around it. Every now and then clean the fossil in a bucket of water, brush on more molten way to newly exposed areas of the fossil, and repeat the cleaning process with acid. Finally, coat the fossil with varnish to protect the fossil from flaking and from wear. (To preserve non-fossilised shells, rub in oil and do not varnish.) Although most fossils are from shells, look out for ones of animals like the Sand Dollar or from seaweed as well.
The diversity of sea shore life is truly enormous and we have only glimpsed a small selection. I hope nevertheless that these articles have inspired naturalists to go out to the countryside and explore. To quote from John Barrett’s Collins Guide to the Sea Coast: “Nothing replaces seeing for oneself, touching, smelling and listening to living animals and plants with all the forces of nature acting upon them. Never mind science for a moment, let the beauty sink in – the colours, movements and adaptations to a hard life are all worth knowing for their own sakes. Then a little later when the questions start to flow, turn to books for answers. However, recognise at once the insidious illusion that understanding can spring from just reading books and watching television. Nothing, but nothing, replaces going out in all weathers and seasons to look more closely at what has been seen before. By all means take books out with you, refer from the field to the page and back again. The books will mightily enlighten the seeing but they can never replace it.”
By David Rees
