The Hawaiian dove population is dominated by two species, the zebra dove and spotted dove. Parts of Hawaii also contain the Mourning Dove, but its population is small by comparison. Zebra doves are the smaller species, with a distinct barred pattern around its neck and shoulders.
Unlike other doves who forage in large groups, zebra doves tend to eat alone or in pairs. They can commonly be found eating short grass or grass seed.
Spotted doves are larger and feature a spotted pattern around the back of the neck. They can be seen in larger flocks and in populated areas have become accustomed to the presence of humans.
Zebra doves were introduced to Hawaii in the 1920s, and spotted doves were likely introduced around the same time. Both quickly spread to all islands and in some areas are the most populous bird seen.
On my recent trip to Kauai, I got plenty of opportunities to photograph both species in different environments. While both seemed to be more skittish than the Nene, I found that if I was still enough and remained low to the ground these birds would eventually approach reasonably close to me.