For example, there was a 20-year lag between the initial introduction and the first outbreak of the European gypsy moth in New England. When the population eruption finally occurs, it is typically rapid and far more difficult to manage. No cataclysm has ensued. Historical documents provide evidence that there was a greenhouse in PPP in the mid to late 1800's and that it is very likely if not certain that the Tetropium fuscum entered at that time - assuming that it was not already here in the first place . However, one opportunity or even a few opportunities does not guarantee invasion.
Invasion is a probabilistic process.
For example, the Great Lakes has received ballast water from transoceanic ships for the past 100 years, yet the zebra mussel and scores of other Eurasian species invaded only late in the century despite having had numerous opportunities to do so previously. Multiple introductions are often required for establishment, particularly for species with separate sexes. The beetles feed only on dead and dying trees in Europe. There is no reason to suppose they will behave any differently here . They are only one of at least 20 species of beetles in the Park.