6. Distinguish between permanent residents, transients, and summer or winter residents or visitors, and accidental visitors.
7. When in doubt as to the identity of a species, never enter it in the record, simply to swell the list. Continued study will enable you eventually to determine the most puzzling occurrences.
8. Record carefully temperature, direction and velocity of wind, and if possible, barometric pressure.
9. Chart the area studied, designating wooded places, pastures, marshy and dry places, roadside, orchards, garden, and water spaces.
10. Study the destination and point of departure of migrating species.
11. Learn both the common names and the scientific names of species if you intend to be strictly accurate. Common names of the same species frequently differ in different localities and are therefore liable to be misleading. Scientific names are easily mastered and usually have a definite meaning, which will help you to remember some distinguishing character or habit of a species.
12. Always be open to fair criticism, and to acknowledge errors in observation. The most distinguished students of any subject are those who profess to have the most to learn. A keen eye and quick brain are indispensable to any student, and calm judgment must always precede reliable conclusions.
A very practical illustration of how a bird-census may be taken is described in Dr. C. F. Hodge’s invaluable book, Nature-Study and Life. The school-children of the city of Worcester, Massachusetts, worked together under Dr. Hodge’s direction, and made a census of the nesting-species in a city block for two seasons three years apart, showing not only the number but also the increase and decrease of nesting-species during that time.
From Marion, Virginia, comes a detailed census of the birds found in the surrounding county during the spring migration. Space is not available for printing in full this census, which includes some ninety odd species, but the method followed, as explained by the following communication, is of interest, and should prove helpful to students in other localities. “The Woman’s Club of Marion has an organized Audubon Society of sixty pupils and four teachers. The three Junior classes are taught once a week from the Audubon leaflets. The Senior Class has helped take the census of Smythe County under the guidance of its teacher. In sixteen field lessons, ninety-four species and eighteen hundred and sixty-three birds of these species have been seen.”