One vital statistic is only implied, and that just barely, in the Australian Transport Safety Bureau‘s report “Australian aviation wildlife strike statistics: Bird and animal strikes 2002 to 2009“. The report lists the number of times various animal species struck (or were struck by) aircraft. But it does not specify what percentage of those strikes occurred in the air, and what on the ground. Here is the report’s summary:
Hare/rabbit strikes were the most common animal struck, with kangaroos, wallabies and foxes/dogs making up the top four…. Three out of four turtle strikes reported for the entire period occurred in 2008-2009, as well as three out of six echidna strikes.