There were 17 Wood Ducks on our pond this morning, with four Canada Geese and a pair of Mallards. Some of the ducks moved from the water into trees bordering the pond, although we have no natural cavities here. There was much courtship activity -- heads bobbing, males chasing, females checking out nesting boxes. We have five boxes surrounding the pond. Two of the boxes had visits this morning by possible occupants. Both Wood Ducks and Hooded Mergansers have nested here in past years. The mergansers were seen here three days ago, but not this morning. We also have one muskrat, an entertaining mammal that we've welcomed before. Two years ago a pair raised four young. Our pond and the swamp behind it hold no native cattails, the invasive species of that plant and purple loosestrife replacing much of the natural vegetation. That loss was underway long before we arrived. I think it poses a food problem the the muskrats. Two nights ago something ate the bark from two tamarac trees, young ones I've been nursing along. I suspect the muskrat. I wish it would eat duck weed and floating algae clumps. We have lots of that.