Some of us are inveterate beachcombers and cannot resist the urge to poke about in the flotsam and jetsam, examine an interesting piece of seaweed or collect a handful of shells. For most people this is just part of a walk on the beach and it goes no further. However, for the naturally curious it is the start of another excursion into the fascinating natural world. This may involve sharing a photograph on the Outer Hebrides Biological Recording (OHBR) Facebook group page, or it can become an absorbing afternoon trying to identify a handful of shells with the aid of a couple of books, a hand lens and help from a really good website. The perfect occupation for a rainy afternoon.
In October this year, I picked-up a small number of shells from Traigh Uige on the west coast of Lewis. This was just a beachcomber’s curiosity, as I had assumed that someone might have already surveyed some of the seashore life on this popular beach. Later, I was surprised to discover that there not even a limpet had been recorded on this part of the coast. This made my handful of shells more significant. Although my random assortment of dog whelks, periwinkles, top shells, tellins and venus clams amounted to only 14 very common species, I had added a new location to the distribution map for these species. This may not seem very important, but without a comprehensive understanding of the biodiversity of our islands, it is difficult to measure the health of our natural environment.
Beachcombing is a popular pastime and recording the animals and plants on our rocky shores and sandy beaches is a good way to add to our knowledge of the wildlife of our coast, Looking at seashells is probably one of the best introductions to animal life on the shore. Don’t be deterred by the term marine mollusc, or the scientific names, Afterall they are just snails that live on the shore. Many of the common species are relatively easy to identify and it is not too difficult to obtain help with the identification.
One of the great advantages of working with marine molluscs collected on the shore is that their occupants have usually disappeared leaving just the shell . In small numbers, they can be safely collected with inflicting any ecological damage or committing molluscicide. Provided the shells are clean, dry and carefully wrapped to prevent breakage, labelled with the date and location, they can be stored to be identified at a later date.
It is not always possible to make an accurate identification from a photograph, but we can usually provide some interesting snippets of information about the natural history and offer some suggestions on how you can develop your identification skills. If a name can be provided together with a location and a date, we have a biological record which will contribute to our growing knowledge of the life on our coast. Our resident beachcombers and visitors have produced some fascinating observations of the plants and animals which live on our coast and those which get washed-up on our shores after a storm. As we live on the edge of the North Atlantic, you never know what you might find.
If you would like to know more about the our coastal wildlife, there are two OHBR leaflets : Marine Life on Sandy Shores and Some Common Seaweeds of the Rocky Shore. You can discover what animals and plants have been recorded on your favourite stretch of coast or beach by using the NBN Atlas Scotland.
Seashells on the Seashore II will tell you a little more about marine molluscs and how to start identifying some of the seashells you will find on our shores.
 Please only take a small number of shells for identification purposes and ensure that they are empty.