1. The effects of temperature on the Oak-Winter Moth-Tit food chain were st
udied at Wytham Wood, Oxford, and experimentally in the controlled environm
ent solardomes at the institute of Terrestrial Ecology, Banger.
2. Tree cores from Wytham indicated that mature Oaks grew best at high temp
eratures and rainfall, but with low caterpillar populations. Young trees gr
ew less well at elevated temperature, probably because they lost more water
than they gained, Elevated temperatures advanced budburst, reduced foliar
nitrogen and increased leaf toughness.
3, Moth eggs laid later or maintained at cooler temperatures than average r
equired fewer heal units to hatch. Caterpillars rook up to 50 days to compl
ete growth at field temperatures but did so in only 20 days at a constant 1
5 degrees C.
4. The mass of Tit chicks at day 15 (day 1 = egg hatch) was positively corr
elated with temperature and negatively correlated with rainfall during the
5. At elevated temperature, budburst and moth egg hatch were synchronized,
but earlier. Late feeding larvae and larvae fed on leaves from trees grown
at elevated temperature produced smaller pupae. Pupal mass was unaffected w
hen caterpillars and trees were maintained together under the same conditio
6. Delaying egg hatch in Tits, to simulate conditions at elevated spring te
mperatures, resulted in reduced chick mass, body size and fledging success.
This occurred because die chicks were fed later and prey quality was poore
r, because the peak of caterpillar biomass was missed.
7. We predict that moth reproductive output will be retained at elevated te
mperatures because both leaves and caterpillars develop faster. Brood size
in birds may be reduced because they cannot lay early enough to coincide wi
th the narrower peak of food abundance.