In a study that was conducted, there were tested two hypotheses that could explain mitochondrial paraphyly of Holarctic gadwalls (Anas strepera) with respect to Asian falcated ducks (A. falcata).
First, hybridization could have resulted in falcated duck mitochondrial DNA (mtDNA) introgressing into the gadwall gene pool.
Second, gadwalls and falcated ducks could have diverged so recently that mtDNA lineages have not sorted to reciprocal monophyly.
The two independent nuclear introns indicated that these species diverged between 210,000 and 5,200,000 ybp, which did not overlap the predicted time for incomplete lineage sorting.
These analyses also suggested that ancient introgression (similar to 14,000 ybp) has resulted in the widespread distribution and high frequency of falcated-like mtDNA (5.5% of haplotypes) in North America.
This is the first study to use a rigorous quantitative framework to reject incomplete lineage sorting as the cause of mitochondrial paraphyly.
[4] It is widely recorded well outside its normal range, but the popularity of this beautiful duck in captivity clouds the origins of these extralimital birds.
[5] During a survey done in Central China, a migratory area in the winter for the falcated duck, the numbers of animals sighted was minimal.
[6] This is a species of lowland wetlands, such as water meadows or lakes, and usually feeds by dabbling for plant food or grazing.
Most of the body plumage is finely vermiculated grey, with the long sickle-shaped tertials, which give this species its name, hanging off its back.
Males use a courting method similar to others in the Anas genus, including an introductory shake, a neck-stretching burp call, a grunt whistle, and a head-up-tail-up display.
[10] A fieldwork study at Hyo-ko Waterfowl Park, a nature preserve in Niigata, Japan, found what they presumed was a male hybrid of a falcated duck and a Eurasian wigeon.
Grunt-whistling, and burping calls being the method of inciting courtship, even resemble that of the falcated duck and not of the Eurasian wigeon.
This hybrid species performed courtship rituals more closely related to the falcated duck, yet socially was active in Eurasian wigeon flocks.
[13] Although the overall population of the falcated duck is larger than once believed and is no longer classified as an endangered species, it is still considered "near threatened" on the IUCN's (or the International Union for the Conservation of Nature's) Animal Red List.
One of the most ecologically sensitive areas in the world is the eastern end of Nanhui county, China, and is a site for the falcated duck during the migratory season.
[10] Falcated duck populations are present in a number of wildlife preservers, national parks and other protected areas,[15] and zoos.
Conservationists are keen to continue monitoring populations that have unfortunately stopped breeding, and plan to petition for hunting and shooting regulations on both the local and national level, respectively.
For hunters who make a living off of either using the falcated duck as a food source or from simple sport hunts, conservationists are looking for alternative employment opportunities.
Finally, conservationists hope to improve the management and coordination of already existing nature reserves where the falcated duck is present.