Fonds consists of Waltho's bird observation journals. Waltho organized his journals in two different ways; daily accounts of bird observations, or monthly summaries of the species observed in Toronto. The first ten volumes in this fonds are the daily observation journals, which are from 1954 to 1964, but with no volume for 1959. These are yearly diaries that Waltho used to record observations on the days he went bird watching. The notes are generally limited to the species spotted (referred to by their common names) and where he was when he observed them. Occasionally, Waltho notes information on birds nests that he found and the number of eggs observed. The last five volumes are his monthly summaries of bird observations from Toronto. These are from 1936 to 1958, but not all intervening years are represented. These volumes are set up like a checklist - the first page lists the bird species and the other sheets check off the species observed each day in a month, with a total at the bottom of each column for the number of birds seen each day. The first volume also has a collection of 76 Wonder Trails by Ellsworth Jaeger, which are short newspaper stories about different species of wildlife, with an accompanying drawing of that animal in its daily life.