Retrieving initial selected item from Ajax populated dropdownlist

I have a dropdownlist that is populated by an Ajax call using a WebMethod after the Page loads.  The way my page is set up, a user can click a search button to get a list of records and then print that list as a report.  If the user changes their selection in the dropdownlist I have no problem retrieving their selection change and forwarding that information to the print function, but it is possible that a user could do a search and click print without changing the dropdownlist selection, and right now I cannot get the initial loaded selection because the dropdownlist is loaded by an Ajax call.  I am using hidden fields in the aspx page but they are showing empty, I assume because the dropdownlist is populated by Ajax after the Page_Load event.
<!-- DropDownList declaration --> <asp:Label ID="lblSelectActivity" Text="Select Activity: " CssClass="lblSelAct" ToolTip="View records for a sele ...