During this season several species will be concentrated into specific locations at a predictable time. By summer the birds will be dispersed to breeding territories and they will be more difficult to find. The best places to go are areas that concentrate the birds on migration. Point Pelee, Rondeau P.P., and Long Point P.P. are excellent. If you're lucky enough to be in Point Pelee when a wave of birds comes through, you can see more than 30 species of warblers in a day.
Warblers are constantly on the move.
In order to get sharp images, higher shutter speeds will be required. To increase magnification, consider decreasing the minimum focus distance by using extension tubes. For example, with our 500mm the MFD is 15 feet, the addition of a 14mm tube decreases this to about 13.5 feet. The use of E.T. will cause some light loss. Another option is to use a teleconverter to increase the magnification at a given distance.