Last Sunday I went down into the Little Maquoketa Valley and checked on the activities of the Cliff Swallows that build their artful mud nest colonies under some of the bridges that cross the river. Several new nests were built and occupied and male and female swallows took turns between feeding and sitting in the nest. They defend their completed nests by sitting in the entrances, puffing up their head and neck feathers to look larger, and lunging at intruders. (source: allaboutbirds.org).
And they have all reasons to defend their nests. Many House Sparrows were present again and took possession of older nests or may have kicked out the swallows before they were able to complete the nest.
And here is a third candidate who liked to attract a female to these cave light mud nests. A male House Wren pulled out grass and feathers, probably from a sparrow’s nest. They usually prepare multiple sites and the female wren chooses the one for laying the eggs.
If you are a local photographer or birder in the Dubuque, Iowa area and like to know where to have a good view, feel free to contact me. Click on the “ABOUT” page and use the contact form. Be forewarned, bug spray and stabile shoes are mandatory for this location. Don’t go there in flip-flops, they will not serve you well!