Will,
IMHO, you first need to decide what type of story YOU wish to write. Will this be a historical narrative w/ bits of entomology, or will this piece you plan to write be a scientific entry, containing bits and pieces of the man you referred to?
Also, consider your audience. For whom will you be writing this story: flyfishermen, other bug-nuts, etc.
What is your ultimate goal with this piece: publication, informative essay, etc.?
I realize the frustration in answering your query with more questions, and I do apologize, but I think that these key ingredients will aid you in coming to the final piece.
HTH,
Dusty