Thw bird walk this morning got rained out, but then it wasn't raining and we went around the trail loop at Thorne Swift Nature Preserve. Lake Michigan was utterly beautiful and the clouds were splendid. The air was balmy and moist. I was surprised at the amount of green algae in the water. Last time I was here it wasn't like that. I looked it up when I got home. Zebra mussels filter the lake water, so the sunlight can grow plant life at greater depths than it did even ten years ago. Then there is always the extra nutrient problem. The green color was interesting, but I really miss the clear lake water.