The Canadian population of Gadwall is at least moderately well monitored by three programs. The Waterfowl Breeding Population and Habitat Survey (WBPHS) is considered to be most representative, as it is designed specifically for waterfowl, provides good coverage of the population, and has high precision. The Breeding Bird Survey (BBS) has similarly high overall reliability. The continental Christmas Bird Count (CBC) results also provide high coverage, but reliability is only medium because methods are less standardized. The WBPHS indicates a moderate long-term increase of 75%, while the BBS and CBC show large increases over the same period, of 206% and 401%, respectively.

The goal for Gadwall is to maintain a population of at least 1.1 million individuals within the area sampled by the Waterfowl Breeding Population and Habitat Survey. This is based on the North American Waterfowl Management Plan's goal of 1.921,000 individuals across the survey's full range, but adjusted to reflect the average proportion of the breeding population in Canada (59%). Data from the Canadian portion of the range indicate that Gadwall is currently within its goal range.