I first became aware of Joel Sartore because of The Great Courses (which offers courses on many different subjects). Mr. Sartore is their expert for the fundamentals of photography (which you can see a listing of here). This is not a sales ad by the way :) My Mom purchased the DVD set for me as a gift - on an amazing sale. So far I have only seen a tiny section of it because I have been way too busy this semester to sit down and watch it, but I will this summer.
What little of it I have seen has made a lot of sense to me. Joel Santore has been a National Geographic photographer for many years, as well as other publications such as Time and Life. You can see his work at his own website, http://www.joelsartore.com/. His passion for wildlife and nature really shine through in his work. He has authored several books and seems to have a very full life.
Ever since I can remember, I have been impressed and amazed with pictures I have seen in National Geographic. My husband and I have watched documentaries showing what the photographers have to go through to capture animals in their natural habitat. It requires a lot of patience, stamina and good humor. Mr. Santore's photos are no exception.
He has a great FAQ's page on his blog. You can find it here. I look forward to learning even more from him this summer.