That is a good looking knife. As was mentioned scrimshaw, engraving and inlay look like the techniques used.
I've done a little research into these skills as I'm interested in making sole authorship art knives as I progress. What I can tell you from my research is that all three are very difficult and costly. I would venture to say inlay is the easiest and cheapest to get the hang of but that is only because the tools and materials can be cheap to start out. I'm only guessing though. If you want to try it and don't plan on making your own gravers and such plan to spend a lot of money and time. Gravers, engraving vices, jewelers tools, etc are pricey and it is a difficult skill to master.
The engraving and some scrimshaw is transferred from art and a type of ink paper (no idea what its called) similar to how they layout tattoos. There are schools out there that teach this stuff and i would recommend it but I lost my book marks. I had a thread on art knives I posted a while back that has some info on these schools. You can search it but I'll post it if I get the time.
For inspiration I also recommend Julie Warenski, I am a big fan of her and her late husband Buster's work. Kyle Royer is also a good person to look at as he is younger and doesn't have decades of experience making knives or engraving but he does both. I do know hes had some training, maybe a lot so take that into consideration.
-Clint