Da. Norton et N. Reid, LESSONS IN ECOSYSTEM MANAGEMENT FROM MANAGEMENT OF THREATENED AND PEST LORANTHACEOUS MISTLETOES IN NEW-ZEALAND AND AUSTRALIA, Conservation biology, 11(3), 1997, pp. 759-769
Loranthaceous mistletoes are interesting because of their complex depe
ndence on suitable host trees nad avian dispersers and because of thei
r patchy distribution at the landscape level. Although their over- and
under-abundance in Australia and New Zealand have been widely documen
ted, little attention has been given to the need of an ecosystem appro
ach to their management. Although the current status of mistletoes is
very different in Australia and New Zealand, some of the causal factor
s and the long-term effects of changes in mistletoe abundance are simi
lar in the two countries. We suggest that mistletoe abundance in pre-E
uropean landscapes was dependent on a series of evolutionary and envir
onmental filters relating to host specificity, pollination, dispersal,
infection, environmental habitat quality, predation, and disturbance.
European settlement modified there filters in a number of ways, resul
ting in either increases or decreases in mistletoe abundance. The thre
e broad groups of changes that have occurred with European settlement
involve fragmentation, predation, and altered disturbance regimes. Alt
hough managers have usually addressed mistletoe over- or under-abundan
ce with short-term solutions (e.g., pruning infected trees), we sugges
t that management must address the underlying causes of the problems i
nvolving mistletoes. This requires an ecosystem approach to management
that addresses both the direct and indirect causes of the current sta
tus of mistletoes.