Sea bean is the name given to a drift seed. That is a seed that can float and drift on the ocean surface driven by the currents and wind, to be washed ashore on a distant beach. The Sea bean website (www.seabean.com) is a good resource, as is the book ‘Sea-Beans from the Tropics’ by Ed Perry IV and John V. Dennis. Some are not beans at all, but fruits that contain seeds.
In the UK there are local seeds that float and can drift a short distance down a river or along the coast. We find conkers (Horse Chestnut), hazelnuts, acorns and beech mast on the strandline, especially in autumn. Some seeds we find, like peach and avocado stones, may have been discarded by beach visitors. We also find sea kale seeds, which use the wind and sea to disperse. These seeds would only survive a short time in the salt water and still be viable.
But then you come to the true sea beans, and it is these that have spectacular journeys. The most common ones that wash up on the northwest coastline of Europe are transatlantic travellers and will have started their journey in Tropical America or the Caribbean. They drop to the ground from a vine or bush, into a watercourse or when rain floods the ground, they float out to the ocean. They can float for up to 30 years (research still ongoing!) and drift on the Gulf Stream and North Atlantic Drift to eventually land on our beaches. To do this, they must have hard, impermeable coats and contain air pockets to enable them to float.
While commonly found in Florida, they are scarce on the west coast of Scotland, Ireland and Cornwall (maybe 1,000 to 5,000 recorded in each area from 1690 to 1990), and incredibly rare on the southeast of England (under 10 recorded from 1690 to 1990).
Sea beans have been drifting across the Atlantic since time immemorial but plastic from the Americas also follows the same currents. Transatlantic plastic is a very important constituent of beach and plastic pollution as non-native species can hitch hike across the Atlantic Ocean and land on our shores, with the potential to cause an imbalance of our own fragile marine and coastal ecosystems.
We think seven sea beans have been found recently by volunteers on Strandliners surveys. Surveys are one of the best ways to find them as they involve close scrutiny of what has washed in.
But we would like to know what you have found so that we can create a Strandliners database of sea bean discoveries on the southeast coastline. Could you tell us what you found, where and when you found it, with a photograph if possible.
We need information including, if possible…
What it is? (Does it need identifying?)
Location, where found (beach/riverbank, lower, strandline or back?)
Date (day or season and year)
Size (“diameter x height” or “width x height x depth”?)
Please email email@example.com with any records, historic included, of these special treasures.