It's because there are no inventories or databases of shipwrecks that have federal legal protection, as there is no federal legal protection at this time. The numbers we gave you earlier are from research done by my colleagues at Library and Archives Canada and by historians who estimate the number of shipwrecks that are currently in Canadian waters.
You may be able to find some information in provincial and territorial databases and directories. However, very few wrecks have been designated by the provinces and territories. For example, the RMS Empress of Ireland , in Quebec, is now considered cultural property, because extraordinary measures have been taken to designate this site and include it in the directory
Unfortunately, there are no numbers because there are no inventories, because there is no federal protection right now.