I'm going on a quest to find some information...still awaiting replies from various experts. I'll keep you posted.
It seems to me that this time of year consistently brings bits of crap washing up on the leeward shores of Lake Michigan. Bits of plants, fish bones, sticks and twigs, sun bleached shells. There's a haze of algae. Good, environmental stewards come out with buckets and bags and pick up man made junk that washes up, too.
In a couple of weeks it will be clear again, and the strand of organic waste along the shoreline will have been buried by sand.
I'm not sure why that happens. Perhaps the waves dig up the waste from last year. Perhaps water currents and temperatures stir up the waters and pull up things that have sat quietly on the lake bottom.
It's not so much stuff that it's unpleasant, of course. We went down to the beach today, and the kids just had more stuff to use with their sand castles, is all. Tree bark used as bridges, water logged sticks used as girders to reinforce sand towers, sprigs of plants or tattered lily pads served as flags and decoration.
It was another scorcher today, and Lake Michigan seems to have a transformitive power. A dip in the lake and the weather seems a lot more bearable for the rest of the day, on into the evening. Though our floor is once again covered in fine beach sand.