Promoting Intertidal Sciences, Conservation & Education Studies | blog | 15th Aug | Dr Mike Kent

A green and pleasant land?

As I approached Baby Bay on a low spring tide , I sensed something was not quite right. The rocks at the water’s edge were covered with a profuse growth of green seaweed, mainly gut weed and sea lettuce (Ulva species). These algae are usually most abundant at the top of the shore or along areas of fresh-water run off, not at the low tide mark where I’d expect a covering of brown wrack and kelp.

The verdant scene did not bring to mind thoughts of a “green and pleasant land”, but of stinking algal blooms associated with pollution, such as that which occurred on 17th March 1967 when the SS Torrey Canyon struck a rock off the Seven Sisters reef. Millions of gallons of oil spewed out of the damaged vessel, turning the sea black. Tides swept the oil onto Cornish shores, leaving them knee-deep in a disgusting brown sludge. Thousands of sea birds were killed directly by the oil. But toxic chemicals sprayed onto intertidal rocks to disperse the oil and clean up the shores caused the algal bloom. The dispersants killed brown seaweeds and limpets. Then, opportunistic fast-growing green seaweeds grew on the vacant plots. With no grazing limpets to check growth, a slippery, smelly and unsightly carpet of algae covered the shore.

I know not what caused the exceptional growth of green algae at Baby Bay. It could have been part of the normal cyclical changes of dominance between limpets and seaweeds. Or it might have been due to extreme weather or pollution. To identify the cause with any confidence requires long-term data about the rocky shore ecosystem. Only by using evidence from the past can we identify the cause of a present event.

Our Scriptures exhort us to be good stewards and take care of God’s creation:


The Lord God took the man

and put him in the garden of Eden

to work it and keep it.

Genesis 2:15

In the context of being stewards of the rocky shore at Baby Bay, we should aim to know the community as well as a good shepherd knows his flock. Then we will be able to care for it properly. Not everyone has the time, resources, inclination or ability to get to know the rocky shore community that well. But, thankfully, we don’t all need to. In Paul’s letters to 1 Corinthians 12:18-28 and Ephesians 4:11-16 he makes it clear that church members belong to the wider church, the Christian body, that has many parts. And God calls all of us to particular roles in it, so that we can serve each other with our particular talents. Therefore, Christians in Polzeath can contribute to the stewardship of our marine environment by supporting anyone who is called to conserve it, and we should value the work they do on our behalf. We should also encourage young church members to pursue a career in marine ecology and conservation if they feel called to do so. This may be no less a Christian calling than teaching, medicine or pastoral ministry.