Wedge-tails are in greater numbers over the WA wheatbelt areas than I've seen in 33 years of flying here. Well known reasons - farmers don't shoot them anymore, and no more chlorinated hydrocarbon insecticides being used. Not uncommon to see 4 in the same thermal. Passed one not long back @ 8500 - it sure gets your attention when you passby and receive a baleful look from a big wedgie!
cheers