ILLINOIS AUDUBON BULLETIN 
Published Quarterly by the 
ILLINOIS AUDUBON SOCIETY 
Number 174 Fall 1975 
CONTENTS 
THE PRESIDENT’S MESSAGE Peter Dring 2 
BIOLOGICAL CONTROLS Robert Van Den Bosch + 
SELF-EXTINCTION FOR THE MOSQUITO A. H. Drummond, Jr. 9 
THE ‘75 SPRING COUNT, REPORT AND RESULTS Vernon M. Kleen 12 
BALD EAGLE WALK — 25 APRIL 1975 20 
WINTERING SWAINSON’S AND BROAD-WINGED HAWKS 
Jim Comfort 21 
GULL AND JAEGER IDENTIFICATIONS Chive E. Goodwin 24 
FIELD NOTES, SPRING MIGRATION Vernon M. Kleen 28 
BOOK REVIEWS: 38 
DUCKS, GEESE AND SWANS By Oscar J. Merne 
THE RIVER KILLERS By Martin Heuvelmans 
THE LIFE OF BIRDS By Joel Carl Welty 
FUNCTIONS: ILLINOIS AUDUBON BULLETIN and NEWSLETTER 40 
Upcoming Events 
Dec. 20 - Jan. 4 Official Christmas Bird Count Dates 
Jan. 15-Feb.15 Period for Winter Bird Surveys 
Apr. 30 - May 2 Annual Meeting, Lakeview Center Auditorium 
Peoria 
FRONT COVER: View of Rock River from Lorado Taft Campus at 
Northern Area Fall Campout. —Photo by Peter Dring 
