The changes in population size of carabid beetles inhabiting an ancient woodland were
analysed in a long-term investigation covering a period of nine years (1994–2002). The
amplitude of fluctuations of the relative density of these species was estimated and
compared with those of carabid beetles inhabiting recent woodlands and more
unstable habitats in open landscapes. To analyse this, 8 pitfall traps were set in an
ancient beech and oak woodland in the nature reserve ‘‘L.uneburger Heide’’ in
northern Germany and were emptied every fortnight the whole year round.
Catching rates for some species (e.g. Carabus problematicus and Abax parallelepipedus)
fluctuated only slightly, whereas those of other species (e.g. C. violaceus and
C. auronitens) varied as much as ten-fold. Comparison of these results with those of
other long-term investigations of recent woodlands and also of more open habitats
showed that in each of the three habitat types some species varied very little in
abundance and others, very widely. So it seems that the amplitude of fluctuations in
abundance is a feature of each single species rather than a special attribute of their