BTUDIPN ON THE INSECT FAUNA O N YUOTCH BROOM
115
on that wtagc of the life history, but unfortunately our data are not
nuflioiontly dutailed for thin conclurrioii. “Wiuter dinappearance” is compounded of Hcvertll factorn, amongst them death caused by predabrs
in litter, which we entimated quantitatively in one year only; death
oau88d by the fungua Beuuveria, which we probably underestimated,
,
.
-
-
k?
0.001
kT/:-:
1
a
FIG. 2. Mortslity affecting Phytode&a oliwrcea at Silwood Park, on logarithmic scale.
K, total mortality; k l , predation on immature stages on broom; k2, egg sterility; k3,
death of immature stages in Boil; k4, winter mortality of adults, including death caused
by BsatMMricr basaiono; k6, paresitism of adulta by Perilitus dubiue; k8, parasitism of
larvas; k7, parasitism of eggs. (Data from Richards and Waloff, 1961.)
and disappearance due to emigration on emergence in spring. By now
we know that many more beetles emigrate than we previously supposed,
but unfortunately we have no measure of this process for the years of
this population study. There is some semblance of direct effects of
density of hibernating beetles and the percentage kill by Beauweria, but
the infection by t,he fungus cannot be independent of the abundance of
its numerous alternate hosts and also of climatic conditions.
B. THE BIOLOGY AND POPULATION DYNAMICS OF
Sitona regensteinenaia
A relatively brief, but nevertheless rigorously critical study was made
byDanthanarayana (1965)inbroomAreano. 5,fromautumn 1962to 1965.
115
on that wtagc of the life history, but unfortunately our data are not
nuflioiontly dutailed for thin conclurrioii. “Wiuter dinappearance” is compounded of Hcvertll factorn, amongst them death caused by predabrs
in litter, which we entimated quantitatively in one year only; death
oau88d by the fungua Beuuveria, which we probably underestimated,
,
.
-
-
k?
0.001
kT/:-:
1
a
FIG. 2. Mortslity affecting Phytode&a oliwrcea at Silwood Park, on logarithmic scale.
K, total mortality; k l , predation on immature stages on broom; k2, egg sterility; k3,
death of immature stages in Boil; k4, winter mortality of adults, including death caused
by BsatMMricr basaiono; k6, paresitism of adulta by Perilitus dubiue; k8, parasitism of
larvas; k7, parasitism of eggs. (Data from Richards and Waloff, 1961.)
and disappearance due to emigration on emergence in spring. By now
we know that many more beetles emigrate than we previously supposed,
but unfortunately we have no measure of this process for the years of
this population study. There is some semblance of direct effects of
density of hibernating beetles and the percentage kill by Beauweria, but
the infection by t,he fungus cannot be independent of the abundance of
its numerous alternate hosts and also of climatic conditions.
B. THE BIOLOGY AND POPULATION DYNAMICS OF
Sitona regensteinenaia
A relatively brief, but nevertheless rigorously critical study was made
byDanthanarayana (1965)inbroomAreano. 5,fromautumn 1962to 1965.