MID-WINTER SURVEY INFO: (Division of Migratory Bird Management, US Fish and Wildlife Service, unpublished data.)
Quantity values from the Mid-Winter Surveys should be clarified in their limitations. These numbers should be recognized as only an “Index” and are NOT purported to be the “number of ducks wintering in each state”. Looking at a state from year to year can be useful, but comparing the absolute values of different states may not be as valid. Different states devote different degrees of effort and, while each is reasonably consistent from year to year, comparisons among states are to be discouraged beyond recognition of those that are “gaining” and those that are “declining” for a given period. The reader is also cautioned to note the year-to-year changes in the total MWI. Planned charts showing the “share” of the MWI in each state may be more useful for some purposes.
2015 Species MWI:
State MWI (1955-2015):
Species MWI (1955-2015):
Mallard MWI (1955-2015):