On my way back from the show in Southern California last month, I had the opportunity to stop by Sacramento National Wildlife Refuge as I do almost everytime I drive down the I-5 corridor. During the different times of year there are different species of birds present and this time, in late March, the marsh wrens were singing and nest building. The singing has two purposes that can distinguished by the sound of the song. The first is to guard it's territory and the second is to attract a mate. This wren was guarding it's territory. Because they are small they can be hard to find among the reeds, but it's song allowed me to find it and study it.