Otter Trapping - Knowledge and Methods by Washington State Trappers Association (book). A "how to" handbook written by trappers who trap otters from the high mountain country to the tide waters. This book consists of the combined knowledge and experience of 17 different trappers who share their favorite otter sets with you. This methods book is a "must read" for anyone interested in trapping otters. Paperback, 40 pages, many photos.