Mike Dilger’s wildlife watching
In his series of great places to watch wildlife in the UK, the star of BBC1’s The One Show this month takes us on an outing to discover rockpools, with tips on seeing their fascinating inhabitants.
The wonderful world of rockpools
Rockpooling can provide hours of entertainment for families during the school summer holidays if you visit a beach at the right time. A rockpool is one of the most ephemeral of all habitats and the lives of its inhabitants are dictated by one thing – the tide. The powerful gravitational forces of the sun and moon have an astonishing impact on our coasts, resulting in two high and two low tides during most 24-hour periods but spring tides reveal the best pools and wildlife.
The constantly varying sea level makes rocky seashores a tough place in which to live as temperature and salinity fluctuate wildly according to the state of the tide. This results in some creatures being baked and desiccated by the sun one minute and then inundated by seawater the next. These demanding conditions invariably create a suite of wonderfully strange animals, many of which wouldn’t look out of place in a sci-fi movie. Rockpool species inhabit different areas of the coastline – some are happiest in the marine environment closer to the low-tide mark, while others that have adapted to being periodically left high and dry can live further up the shore. ‘Time and tide wait for no man’, so to get the most out of your rockpooling experience, knowledge of the state of the tide is crucial. The best time to arrive at the beach is when the water is either rapidly receding, or at its lowest ebb – head straight for the lowermost zone of the shore. The rockpools in this region will be uncovered for the least amount of time and frequently contain the most interesting finds. You can then proceed up the shore, while remembering at all times to stay ahead of the incoming tide. It’s
worth bearing in mind that many inhabitants are sensitive to vibrations, so sitting quietly next to a promising rockpool may enable you to observe the shyer species. The general consensus is that nets should be used very carefully in such a fragile environment – hands and pots can be easily as effective when you know how and where to search. Lots of rockpool creatures have distinct niches, with some preferring to conceal themselves beneath seaweed or on the underside of an overhang, while others hide underneath boulders or in crevices.
Be considerate
You should also remember that you are intruding on the private world of these species, so stones and seaweed should always be carefully replaced. While keeping your finds in a bucket will let you admire them up close, it is important to remember not to create a food chain in your container, where larger predators are able to pick off lunch at will. Don’t keep them in the bucket too long, either. Once you’ve observed your catch for a short time, put the creatures back in the same pool you found them in – species collected from the lower shore will not survive for long if placed back in a pool on the upper shore.
Before your beach visit, don’t forget to pack non-slip footwear to avoid sliding on rocks or falling over. The seashore can be a hazardous place so take your time and remember to keep an eye on the tide as you enjoy searching the magical pools for bizarre critters.
“Don’t create a food chain in your bucket and put your catch back where you discovered it.”