Over the last five years research has found that kelp beds are expanding northwards and contracting their southern ranges. This has been, in part, attributed to human impacts, through overfishing of top predators (for example cod (Gadus morhua) in UK waters), changes in current flow, increases in sea surface temperature, changes in nutrients and sedimentation and heat waves, which may lead to kelp drying out on the beach. These lead to an increase in grazing from sea urchins (Echinoidea), competition from southern seaweeds and a consequential decline in the local kelp beds.
Hannah Hereward, joint A Rocha UK and A Rocha International’s marine researcher, is partnering with Lee Abbey in Devon. Hannah is also undertaking a part-time masters in Marine Biology at the University of Plymouth. Hannah has spent the last few months assessing Lee Abbey’s, Lee Bay beach. The combined opportunities have led to Hannah focusing on the interactions between kelp (Laminariales), blue-rayed limpets (Patella pellucida) and heat waves for her internship and dissertation thesis.
Kelp is the largest seaweed found across the world. It covers 19,000km² of the UK coastline. This combined with 11,000km² of another seaweed family, equates to around the same area covered by broadleaf woodland in the UK, an area equivalent to the size of Wales.
Kelp is an important habitat for many species, including the blue-rayed limpet, which almost exclusively relies on kelp for grazing. Kelp is also of benefit to humans because it processes atmospheric carbon, is of high economic value (indirectly, by providing habitats for economically important fish and directly, for alginate) and it provides a natural coastal defence.
Stay tuned for more information as Hannah completes her proposal and prepares for the coming field season!