I had a boatyard on the Tamar for 7 years. It was 7 miles upstream from The Narrows at Devonport but tidal, right up to Morwelham Quay, a further 7 miles upstream.
Despite the freshwater draining off soggy Bodmin Moor and the sea flooding in twice daily, the Tamar is a dodgy place to source edibles. The Tamar valley at this point was the biggest arsenic, tin and copper mining area in Europe, in Victorian times.
At The Silver Mine, 1/4 mile down the lane from the yard, the spoil heap is completely free of even brambles, well over 100 years after mining ceased.
In addition, the village of Bere Alston had, in my time at least [92-99] a sewer that ran untreated sewage into this famous salmon river.
Last but not least, the river shows raised levels of radioactivity due to the nuclear subs docks at Devonport.
With all this in mind, my shipwright decided to try the ‘wild’ oysters that can be found further downstream. He was extremely sick. On the basis that he might just have picked a bad one, he tried again. Same result.
You can see the high tension lines crossing the river over the old mine.
The cables are just the right height to cause confusion to the many flocks of birds that used the river as a m/way. Go over or go under? The 110,00 volts can’t have helped them decide.
One day the same chap came in off the river with a freshly killed Canada goose. It had flown into a power line. Next day his wife, my PA, brought in Canada goose breast sandwiches. I have never actually eaten muddy pond weed but from the smell of it, that’s what Canada goose breast tastes of.
'orrible