PE EIE[R-Rg RESEARCH ON - HJ Andrews Experimental Forest

Further Studies
The data provided for small mammal populations
will be more useful if we are able t o
make more accurate population density estimates
and if we determine the yearly, seasonal,
and geographical fluctuations in
density. Further, a more detailed understanding
of population dynamics will permit a
more accurate estimate of energy flow, and
set the stage for studies of uptake, storage ,
and loss of chemical materials by smal l
mammal populations .
Of course, the same sort of informatio n
must be obtained for the large mammals ,
which include several important primary consumers.
For large mammals the role of movement
must be studied, since seasonal movements
entail a translocation of materials, an d
patterns of mortality provide loci of nutrien t
release .
For birds the study of movements will also
be important, since long-distance annua l
migrations provide a potential mechanism for
the annual loss of materials from the ecosystem
.
A prime consideration in all such studie s
will be the establishment of confidence limits
for the data, and estimates of additiona l
sampling necessary for results of a stipulate d
level of accuracy . Then we will be in a position
to respond to the needs of modeling in a
realistic way with regard to the actual field o r
laboratory work which provision of any particular
piece of information will require .
In addition to these inventories of vertebrate
animals in the forest ecosystem, we will
seek an understanding of the effects that
animal populations may have on the populations
of plants which constitute their food ,
i.e ., the control function exerted by animal s
over plant populations. A knowledge of suc h
relations, properly quantified, will help pro -
vide the basis for models of the dynamics o f
plant populations .
Acknowledgments
This study was supported by the Department
of Game, State of Washington ; Institute
of Forest Products, University of Washington ;
Ecology Training Grant from the Nationa l
Science Foundation to the Zoology Department,
University of Washington ; and by
National Science Foundation Grant No .
GB-20963 to the Coniferous Forest Biome ,
U .S. Analysis of Ecosystems, Internationa l
Biological Program . This is Contribution No .
36 to the Coniferous Forest Biome, IBP . We
also wish to thank the personnel of the Cedar
River watershed and the Seattle Water Department
for their assistance and cooperatio n
throughout the study .
Literature Cited
Adamczyk, K ., and L . Ryszkowski. 1968 .
Estimation of the density of a rodent popu -
lation using stained bait. Acta Ther .
13(17) : 295-311 .
Babinska, J ., and E . Bock. 1969 . The effect of
prebaiting on capture of rodents . Act a
Ther. 14(19) : 267-270 .
De Lury, D . B . 1947 . On the estimation o f
biological populations. Biometrics 3 :
145-167 .
Gebczynski, M . 1965 . Seasonal and age
changes in the metabolism and activity o f
Sorex araneus L . Acta Ther. 10(22) :
303-331 .
Gorecki, A. 1965 . Energy values of body in
small mammals . Acta Ther . 10(23) :
333-352 .
Grodzinski, W ., Z. Pucek, and L . Ryszkowski .
1966. Estimation of rodent numbers b y
means of prebaiting and intensive removal .
Acta Ther . 11(10) : 297-314 .
Hayne, D . W. 1949 . Two methods for estimating
population from trapping records . J .
Mammalogy 30(4) : 399-411 .
Leslie, P. H. 1952. The estimation of population
parameters from data obtained by
means of the capture-recapture method. II .
The estimation of total numbers . Biometrika
39(3&4): 363-388 .
McNab, B . K. 1963 . A model of the energy
budget of a wild mouse . Ecology 44(3) :
521-532 .
206