Last night, Susan surprised me with dinner and talk by Paul Nicklen.  Paul is one of the top environmental & nature photographers. He specializes in the polar regions. His credits include numerous assignments for National Geographic Magazine. His prevention consisted of many stories of how he got the shot. He was very informative and funny. One interesting point, Paul takes credit for starting the DSLR revelation at Nat Geo. His point was that when you are under the ice and you only have 36 film exposures, you will miss a lot.  So once DSLR matured he started using them.  He could now shoot 1000+ exposures without having to surface.

Here's a TED talk he gave in 2011.

Paul's Instagram page.