Hermit crab one takes it over. For some larger marine species, supporting one or more sea anemones on the shell can scare away predators. The sea anemone benefits, because it is in position to consume fragments of the hermit crab's meals. Other very close symbiotic relationships are known from encrusting bryozoans and hermit crabs forming bryoliths. When properly sized gastropod shells are not available, hermit crabs have been known to resort to wearing other objects such as tree nut hulls or pieces of beach litter rather than go unprotected. This has become very common in some areas, due not only to the
Invasive species which were brought to control insects upon the introduced grain crops, have displaced native birds as have rainbow lorikeets and cockatoos (both from Australia) which fly free around areas west of Auckland City such as the Waitakere Ranges. In much of New Zealand, the Australian black swan has effectively eliminated the existence of the previously introduced mute swan. Two notable varieties of spiders have also been introduced: the white tail spider and the redback spider. Both may have arrived inside shipments of fruit. Until then, the only spider (and the only venomous animal) dangerous to humans was the native katipo,