Currently, the only ways to tell the number of caravans you have are:
a) Look at total worker count, then do mental arithmetic to find out the number of caravans.
b) Select a caravan, then use the "select all units of that type" hotkey.
Both methods are less than ideal, and wastes several second every time you want to check it. If showing it on the UI is impossible, an alternative would be a "select all caravan" hotkey, which would be almost as good.
a) Look at total worker count, then do mental arithmetic to find out the number of caravans.
b) Select a caravan, then use the "select all units of that type" hotkey.
Both methods are less than ideal, and wastes several second every time you want to check it. If showing it on the UI is impossible, an alternative would be a "select all caravan" hotkey, which would be almost as good.