I'm glad you asked! There are so many interesting people and places in Fiordland, so many stories (both true and not-quite true), so I would really encourage you to do some digging for yourself and see what else you can find out about the people and places mentioned in my book. Fiordland really is one of the world's last great wildernesses, and we should, I think, do our best to both understand it and to protect it. Here's some of the books that helped me with my research for Spark Hunter. Some of them are pretty old but you might be able to track down a copy of some of these if you are keen:
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Some of the other's that were of particular use to me in The Secret Green included:
Tamatea Dusky by Peta Carey, Bird Stories by Geoff Norman, Six-Legged Ghosts by Lily Duval, Treasures of Tane by Rob Tipa, Fungi of Aotearoa by Liv Sisson, Farthest West by AH and AW Reed, The Forgotten Forest by Robert Vennell, Traditional Lifeways of the Southern Māori by James Herries Beattie, Minerals and Gems of Māoriland by WM Campbell, The Treaty of Waitangi and the Ngai Tahu Claim by the Ngai Tahu Trust Board, as well as all those books you can see in the picture above.
I borrowed lots of turns of phrases from some of those old books written about Fiordland for my historic characters, and for the sparks' dialogue. And I was very inspired by some of the ideas about nature and the environment that I read about in books by amazing scientist-writers like Suzanne Simard, David George Haskell, Peter Wohlleben and Robert Macfarlane. Some of the sparks' views on life and forest can be traced back to these wonderful books.
There's a swathe of great information available online too, of course.
I found the Papers Past website great for finding old articles written about the mysteries of Fiordland:
National Library's Papers Past - The Otago Witness(https://paperspast.natlib.govt.nz/newspapers?snippet=true&query=Otago+Witness)
Ngāi Tahu's website is good for a bit of local history, too. Their Kā Huru Manu project is really cool - it's an atlas showing all of the original Māori names for the rivers, lakes and settlements in Te Wai Pounamu; zoom into Fiordland and you can see not only what places were named, but why:
Kā Huru Manu, Ngāi Tahu's cultural mapping project(https://www.kahurumanu.co.nz/atlas)
If you are visiting Fiordland National Park and want to do a walk or two (which you absolutely should) a good place to start is the Department of Conservation website:
Fiordland National Park(https://www.doc.govt.nz/parks-and-recreation/places-to-go/fiordland/places/fiordland-national-park/?tab-id=50578)
If you want to find out more about kākāpō or donate to recovery efforts:
The Kākāpō Recovery Project(https://www.doc.govt.nz/our-work/kakapo-recovery/)
(https://www.doc.govt.nz/our-work/kakapo-recovery/)
You can find out more about other New Zealand birds (even the ones that are now extinct) here:
NZ Birds Online(https://nzbirdsonline.org.nz/)
If you are in Southland, I recommend visiting the Southland Museum (https://southlandmuseum.co.nz/)in Invercargill and the Fiordland National Park Visitor Centre.(https://www.doc.govt.nz/parks-and-recreation/places-to-go/fiordland/places/fiordland-national-park/fiordland-national-park-visitor-centre/)