Brood Survival - Hatching Dates 
Data on Brood survival and hatching dates has baen sathared during beth 
the 1948 and 1949 ssasons on the Klamath basin and related areas in the North- 
eastarn California ragion. Figures for these two yaars are of a comparables 
natura as presented in Table 4. (See Table 4} 
As proviocusly saxpleainad, brood counts in the Sacramanto Vallsy ars difficult 
to obtain in sufficisnt numbers to ba of valus in dstermining batching datee, 
poms indication on dats of hateh has been obtained from aesst studiss both during 
1948 and 1949. Theas data are summarized in Table 5. 
Table 5 
Dats of Hatch - Sacramento Valley 
1948 1949 
(Porcent Hatched) [Percent Hatched} 
Week Period 
April 21 - 30 F 
May 1l1- 2 
May m=—- lA 10 ii 
May 15 - «2k 41 2 
ay ae o- ah 24 5 
May ay =- Thane & 17.5 28 
7uns 5-11 12.4 33 
June 12 - 18 5 9 
June 9 - 25 vi 
June 26 - July 2 Q 
July [ek 3 
1948 - data based on 19 nesta ~ 61 brood observations 
1949 - data based on 58 nests of kmown data of hatch 
Clinatic Influenesa 
Generally speaking, climatic influences are not felt ta bs of much signifi- 
canes in thoss regions of the Stata whare watar conditions are artificially 
eontrolied dus to agricultural demands, In the northeastern Califormia region, 
apring rainfell ia important. Later spring rains tend to maintain water lerals 
in natural marsh arses. “+ack of late apring rains resuits in ths drying up of 
these areas and young broods fail to reach maturity sinc? no other watsr arsag 
ara available lecally. FPraduction in this arasa in 1949 was lower than in 1944, 
Que largely to the pattern of rainfall distribution, 
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