Wednesday, 13 February 2019

Dame Allan's John Muir Challenge

Last week, a hardy group of students completing the John Muir Award were challenged to explore and conserve a natural environment. 16 pupils from Dame Allan’s School in Newcastle braved the icy wind to study the winkling activities around St. Cuthbert’s Island. The data the students collected will contribute to future management plans of the rocky shore around the Reserve. 
People taking periwinkles off the shore to sell or use as bait is an increasingly popular activity, and often a huge amount of biomass is being removed in one episode. The effect it is having on the wider ecosystem requires further study.

The students were tasked with investigating patterns in the distribution, abundance and size of three marine snails; Common Periwinkle, Rough Periwinkle and Dog Whelk. The profile of the rocky shore surrounding St. Cuthbert’s Island allows for quite a sheltered environment, which periwinkles prefer rather than large waves crashing against the rocks. Because of this, we would expect them to be more abundant on the mid shore. We also would expect smaller individuals to be more abundant as winkle pickers are more likely to take the larger ones. 

The data collected showed a higher abundance of all three species at the mid shore compared to the lower shore.

There was no significant difference in the lengths of the two periwinkle species on the different shore heights, however the length found at both locations was relatively small. The average length of a Common Periwinkle is 2.7cm, compared to the 1.4cm average found on the mid shore. This could suggest that larger individuals are being removed and the population is not having enough time to recover between episodes of winkling, bringing the average size of this population down.  

After leaving the shore at mid-day, the students headed out to Sandham Bay on a much-needed walk to thaw freezing fingers and toes! They were in search of a small but mighty threat to the wildlife in both in the marine and terrestrial environment… Nurdles. 

These are tiny pieces of plastic that end up in the sea which attract harmful and toxic chemicals. Like other plastics they are being mistaken for food and are consumed by animals such as fish and birds, being absorbed into their tissue and hence passed on to anything that may then eat it… whether that be animals higher up the food chain or humans. This is known as bioaccumulation and can cause all sorts of health problems. 

Upon arriving on Sandham Bay, the beach appeared relatively clean, however on closer inspection, small pieces of plastic were found tangled in washed up seaweed. Ghost fishing gear, from three large lobster pots to well-camouflaged bundles of fishing line, yet again made up a large proportion of the litter collected. The students did a great job cleaning the beach, with three large bags of rubbish safely removed. 

The students had a great day and returned to Newcastle with a better understanding of the work done on the Reserve to protect the species living there. They also appreciated the dangers plastic poses to the natural environment, from the obvious threat of entanglement in rope and plastic bags, to the bioaccumulation of small and microplastics up the food chain.
For more information on Nurdles, see

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