At the bottom of page 10, in a recently delivered well known canoeing magazine, there is a mention of tobacco and copper offerings to Maymayguaishi.  (spelling varies)

Since our first trip we have always left a pinch of tobacco, but have never seen the copper reference.  Maybe we can we blame our poor fishing and general bad weather on that omission?

Searching for copper offerings, all I found was Tibetan comments.