This is fairly easy to do using my logging program Log4OM. First I set up a special Search Parameter, finding all contacts where the SIG field is WWFF. All my contacts with WWFF parks have this Adif field set to this value.
I can then display just WWFF park contacts in Log4OM. Changing the layout can see the SIG and SIG INFO fields, the SIG INFO field has the park number worked.
To fill in Grid Squares, for each park used the ParksnPeaks website, Parks link to look up each park, which in the park details has the Grid Square. eg for VKFF-0618 Alfred National Park, the Grid Square is QF42qk.
After filling in all park contact Grid Squares, selected them all, and used the "Plot KML"button to plot them all out in Google Earth. I chose to use 4 digits only and 3D View based on QSO count.
Here is the final result in Google Earth, displaying all Australian Grid Squares that I have chased a park in.
The park activations grid squares worked line up with population density pretty well, for overseas readers the population of Australia mainly live close to the West, South and East Coasts, the Centre of the continent is mainly desert and sparsely populated. I do have a few out of the way parks though.
There are peaks in parks numbers worked in Adelaide, Melbourne, Canberra and Sydney Grid Squares.
Heres how I'm going so far for each call area/state
VK1 - ACT
Easy, all in one grid square, QF44. I do also live there :)
VK2 - NSW.
There is a shortage of grids worked in Western NSW, probably due it being semi-desert and not many people. I have worked some of the remote areas though such as Sturt NP in the far North West corner. Surprisingly have not worked any parks just North of Canberra in QF45, although have worked Amateurs there, eg in Yass. Also a hole in the Coast in QG60 around Grafton, but have worked stations in this area, just not in parks. Probably take some time to get them all...
VK3 - Victoria
I have got the whole State covered! Its a small state rich with Parks and Amateurs to activate them.
VK4 - Queensland
Mainly in the South East and some up in far North Queensland. Its a really big state... Have to wait for expeditions to fill in the gaps...
VK5 - South Australia
The South East, where most of the population lives is well activated. There have been a few expeditions to say the Flinders Ranges to get some of the inland squares.
Some of South Australia is restricted access, eg Woomera and Aboriginal land in the North West, so will be hard to get all squares.
VK6 - Western Australia
A vast area with most of the activity around the South West corner. To activate parks in the North looking at weeks of travel to get there... Have managed to get a few rare grids though.
VK7 - Tasmania
Although small it will be hard to make park activations on the West Coast, wilderness with no roads, and long tough walking to get to.
VK8 - Northern Territory
Despite a few park activations have not worked any yet. Most is desert and low population, and permits are required to enter aboriginal land. Plus its too far away to reach on 40 m here in the daytime, so need good propagation on say 20 m to work.