Having not noticed any bumble bee activity from the remaining part of rotten decking I'd had to put a halt to removing a while back I re-commenced the removal and found where I'd expected to find an abandoned bees nest, a mass of the most incredibly tough and virtually impossible to tear "silk".
This indestructible matted mass was extracted and several caterpillars wiggled out. After a failed attempts to remove more caterpillars I rolled the cocoon thing between my hands and "swarms" of caterpillars wriggled out into the collecting bowl. Thinking nature knows what's good to eat I tossed a few into the pond.
Koi absolutely loved them so yesterday they dined in style on brown bread and Wax Moth caterpillars.
Hadn't heard of the Wax Moth and how it destroys bees, but on investigation it's also being looked into as it's enzymes can also break down plastics! Quite amazed at just how incredibly tough their silk is more than anything.