Yvonne,
Well, the BIF (birds in flight) shots were all handheld using my 70-300 zoom lens or a friend's borrowed zoom (I can't hand hold my 300mm f/2.8, but the lighter zooms are doable), but the others (especially if they're at 500mm) were all either taken from a tripod and a
Wimberley Head, or just propped on my car window (no, I don't have a window pod, but I plan to get one before my next trip back down to Florida). In general, I stayed in my car at the Viera Wetlands, as the birds were pretty close and tended to spook if we got out.