Since thre seemed to be some confusion about your question, Sato2, let me wade in here.
On landing, you declare only the cash you are carrying with you (above $10,000). Income you will receive later, once in Canada, is handled two ways. Yes, your bank will inform FINTRAC as it receives wire transfers into your account. The bank may also ask you for more information about the source of the funds, including perhaps asking or a declaration from a source bank.
Pensions received from offshore will be taxed in your Canadian tax return, and there is a place in the return to state taxes paid in the source country -- which reduces your tax payable to Canada.
If -- as PMM says -- there is no tax treaty between Canada and the source country, you may be taxed twice on this income. This is where a good international tax accountant might be useful. Otherwise, just follow the Guide for your tax return. Or, better yet in my opinion, buy QuickTax. For about $40 it simplifies the tax return immensely.
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