Proper Names

Q. Dear Editor, I was wondering if you could help me with a style query. I am copyediting a 10-chapter document on fish. The author has asked me to include the scientific name in parentheses after the common name of fish species. It seems to me that repeating this each time the fish is mentioned would make the text bulky (the names are repeated often in each section). Can we mention the scientific name of the fish in parentheses just once in each chapter, or should we keep repeating this style after each species is noted? I hope I’m being clear. . . . Many thanks for your advice on this!

A. Just once is enough. According to Scientific Style and Format (published by the University of Chicago Press and, like CMOS, available online), “If the organism is widely known by a vernacular name, this may be used if, at the first reference to the organism, the vernacular name is presented in clear association with the Latin name.” See SSF, section