During the past few years a few things have begun to occur more often; firstly, more and more of you are spending an ever increasing amount of time in the USA, and, secondly, the IRS(Internal Revenue Service), also known as the CRA of USA taxation, has begun inquiring more and more about various aspects of foreign ownership and residency in the USA.
In other words, they are inquiring because they want to know about you, they want to know what you own in the USA, and they also want to know how much time you're spending in the USA.
I regularly receive requests or updates from clients on this matter. This has happened with ever increasing frequency over the past 2-3 years.
Recently Terry McBride of Raymond James in Saskatoon wrote a fairly comprehensive article "Snowbirds need to think about American Taxes" published in the Saskatoon Star Phoenix regarding residency and taxation for Canadians who spend time in the USA.
If you are vulnerable or potentially in danger regarding how much time you spend in the USA I recommend you consult with your tax professional to ensure you are completing the proper forms and paperwork at tax time.