But today, de Gelder is fitted with state-of-the-art prosthetics and is back on the job. He is the author of “No Time for Fear,” an inspirational book about his experiences. As a shark conservation advocate, he believes everyone has an obligation to protect sharks and the important role they play in the ecosystem. De Gelder was among a group of shark attack survivors who joined the Pew Environment Group in 2010 to press the United Nations for improved shark conservation measures.