The efforts to protect bird deaths from window crashes is great to see! Clarification of the statement, “They found about 10 birds ...” would be very helpful. Does this mean 10 individual birds, or 10 bird species? “Many of them tropical migrants” suggests that it is 10 bird species, but this is not clear.

Editor’s note: The students found about 10 individual birds, mostly of species that are tropical migrants and cross Princeton each year on their journeys north and south.

William E. Heyd ’67
Kalamazoo, Mich.