It's the coldest stretch of the year, but can spring be far behind as Walnut Creek's urban ducks begin to pair up.
Walnut Creek naturalist Brian Murphy took this photo of mallards and wood ducks behind the Broadway library last week.
"Wood ducks are at the top of the photo and mallards are in the photo as well – the eye strip around the female wood duck eye makes identification easy while the colors of the male wood duck are very easy to spot," Murphy reported in an email
"Mallards are ground nesting ducks while wood ducks nest in cavities found in old growth trees. In an absence of old growth trees, wood duck nest boxes work very well. The wood duck pair in the photo will soon begin to look at wood duck boxes in the creek and pick one to nest in this year."
Murphy is a volunteer with the Just For Ducks program of the Mount Diablo Audubon Society.