Yes you can apply capital losses back up to three years.  It is not automatic as you have to choose to do so.  If you do you won't see the difference on the 2015 return...essentially CRA will adjust the 2013 return and send you the resulting difference.  

If you have trouble with this
Please call us by clicking the following link to the Contact Us page. Then complete the required information. A phone number will appear, along with your incident ID. Call the number. This will ensure that an appropriate agent is assigned to your query:

https://support.turbotax.intuit.ca/contact/
We look forward to hearing from you.