Bay Photos by Donna

With some birds, it appears there’s almost no way of telling which is male and female by looks alone. Some may have just slight, maybe hardly noticeable differences. And for others, it’s quite obvious between the two sexes. The reasons for this are simple.

The male and female of a bird species that looks different (sexual dimorphism) is because of their mating, behavior, and survival pressures. The males develop bright plumage and songs to attract females and fight rivals, while females are drab for camouflage while nesting and brooding. These birds usually do not mate for life.

Bird species where both sexes look alike (monomorphism) often share high nesting duties with nest building, incubating eggs and protecting territory as well as hunting, making camouflage equally important for both sexes. They will also mate for life.

When birds sexes do look different, we often associate the bird with the male’s look and gorgeous coloring. Learning the females can be difficult sometimes as they look no way near like their mate. However, when they look alike, learning what is the slight difference that tells you it’s a female is the ID key.

Compare for yourself!

Northern Cardinals
(male left, female right)

Red-bellied Woodpeckers
(male has red on head/nape, female only on nape)

Northern Flickers, Yellow-shafted
(male has black ‘mustache’, female not)

Eastern Towhee, Red-eyed
(male on left, female on right)

House Finches
(male on left, female on right)