Koloa Mōhā
Names
- ʻŌlelo Hawaiʻi: Koloa Mōhā
- Common: Northern Shoveler
- Scientific: Spatula clypeata, Anas clypeata
Song
Conservation Status
- State recognized as Indigenous
Species Information
The koloa mōhā, or northern shoveler, is a common North American dabbling duck (Family: Anatidae) that winters in the Main Hawaiian Islands (MHI), typically arriving in September and October and departing for Alaska by March or April. By virtue of their unusually large flat bills, koloa mōhā are adapted to a diet primarily of aquatic invertebrates such as water fleas (Daphnia spp.) and crustaceans (copepods and ostracods), which they obtain by filtration. In addition to nektonic prey, however, koloa mōhā are also known to eat seeds and gastropods. Like many ducks, koloa mōhā are sexually dichromatic in plumage, with breeding males sporting a dark green head, white throat, and brown belly, in contrast to the females’ more uniform mottled brown plumage. Koloa mōhā are less gregarious than other dabbling ducks, are among the most territorial during breeding, and maintain pair bonds longer than other similar species. They are known to hybridize with at least three other North American duck species (blue-winged and cinnamon teals, and muscovy ducks) and with several other species in Eurasia.
Distribution
Common throughout the southern and western United States and Mexico during the winter, shifting to the northernmost central U.S., west central Canada, and Alaska during the breeding season. Koloa mōhā are also common through Eurasia. In Hawai‘i, koloa mōhā have been sighted routinely on all of the MHI, but have not be recorded in the NWHI.
Habitat
During winter, koloa mōhā utilize a variety of wetland habitats, including freshwater and saline marshes, and agricultural ponds. They prefer shallow open lakes containing dense growth of aquatic vegetation, and tend not to forage on dry land. In Mexico, they are known to inhabit coastal lagoons, estuaries, and some mangrove swamps. Some of these areas are already protected, but much habitat has been lost to development.
Threats
Primary threats include the following:
- Loss of wetland habitat to development, pollution, or habitat-modifying invasive plants.
- Avian disease.
Plans & Projects
Additional Resources
For more information and references visit the DLNR State Wildlife Action Plan factsheets. DOFAWʻs species pages and State Wildlife Action Plan fact sheets are provided for general information and are not meant to be a citable, original source of data. If you are a student, researcher, or writer looking for a citable source, please explore the references below or find other original data sources, rather than citing these webpages. The references below were provided by the authors of the State Wildlife Action Plan fact sheets at the time of drafting:
- Dubowy PL. 1996. Northern shoveler (Anas clypeata). In The Birds of North America, No. 217 (Poole A, Gill F, editors). Philadelphia, (PA): The Academy of Natural Sciences; and Washington DC: The American Ornithologists’ Union.