WATERSOKL BREEDING GROUND SURVEY IN mICHIGAN, 1949 
H, J. Miller 
During the past two yoare personnel pf the Uspartment of Conssarvation hares 
made definite sfforta to determines the production potential of watsarfowl in Michi- 
gan. Although some significant data have bean obtained, the material ig 
insufficient far arriving at an estimated breasding population or an estimatad 
breeding population or an sstimate of production of any larg? area’ on a quanti- 
batiys basis, 
A majority of Michigan's waterfowl nesting arsas are in ths heavy cover 
of ths intaricr of ths Stats. A fsw important nesting arsas are found in ths 
Southern agricultural lands, but a large portion of cur production occurs in 
the vast forested rogions of the northarn two-thirds of ths State, ‘tater is 
not lacking, as thousands of strosama, lakes, swales, and bearer ponds ars 
scattered throughout this region. Hreadineg birds ars scatters and difficuit 
to locate as the heavy cover is a sasrious limitation to acenrata tengusing. 
Guided by previous axperisnes, we have confined our efforts to thrss types 
of surveys: 
1. Agsrial census of ssleetsed areas tao determines potential 
bresding population in ths southern farm lends, 
2. Surface cansuses or ground checks of potential breeding 
populations on sample argsas to obtain greater coyeragrs of thea 
otats, 
3. Brood censuses of the same sample areas to determines brood 
densitiss and survivel. 
Sample arsas were ceresfully aslected as the sama surveys will bs continued 
ta provide a comparative index of changes in production from ons year to another, 
Aerial Censuses 
Ths threa sampl? areas csnsused by airplans wars tho same as flown in ths 
spring of 1948, sxcopt that an additional township was included in the Barry 
County area in 1949, This accounts for ths differents in coresrags ahown in ths 
Table below. Ths two yaars of field date f¢ivs an index of change in breeding 
potential. Species eonaidsrad as uncommon bresdsrs in Michigan wers excluded 
from this computation. 

Location and siz? of Census a-%8 Local nesting ducks per squars mils 
(Ses Figura 1) 1948 1949 
Barry Co, (Block types coverages} f166 sq, miles) [202 sq. miles) 
{108 sq. mi. in 1948 and 144 aq. mi. 
in 1949} rl 4 
Ingham, Livingston, Oakland counties 
[18 square miles} 2.2 2.06 
Laks Eris Marshes, Monrat County 
(40 squers miles) 4.22 °10,455 
Averages 1.39 3.38 
134 
