At a national scale, the best source of data on the population status of Caspian Tern is the Breeding Bird Survey (BBS). Although it only samples a moderate proportion of the population and has medium precision, it provides data for all regions where the species occurs. Conversely, the Great Lakes Decadal Colonial Waterbird Census (GLDCWC) is better suited to detecting terns, but has a more limited geographic scope, and has been completed only four times over a 50-year period. The GLDCWC indicates a moderate long-term increase in abundance since the early 1970s, which aligns with the large increase shown in the national BBS trend. The BBS indicates a steady increase from the 1970s to a peak around 2010, and a subsequent decline. Surveys in Manitoba, home to some of Canada's largest colonies of Caspian Tern, also show evidence of an overall increase, although not in the most recent survey, which was affected by high water levels. However, the small Atlantic coast population may be experiencing a decline (Wires and Cuthbert, 2000), and the species has been listed as threatened in Québec since 2009 based on only breeding in the province sporadically (Gouvernemement du Québec 2010). 

The goal for Caspian Tern is to remain at or above its recent population level, based on the Breeding Bird Survey. Trend data show that Caspian Tern is currently within its goal range.