These pictures come from Kilchoan Early Bird who writes, "I found this fresh water eel in a river today. I've not seen one in years - that said I've not really looked in years! The glass eels will have gone up the river by now. They arrive here round about the end of March, at the first full moon. This one was about four inches long."
The larvae of European eels travel with the Gulf Stream across the Atlantic Ocean, and grow to 75–90 mm within three years, before they reach the coasts of Europe. When they swim upstream they're called 'glass eels' because of the their transparency.
I had never thought that eels come in to Ardnamurchan's rivers: something else to look out for.
Many thanks to Kilchoan Early Bird for pictures and story.