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NUMBER 89 95
counterparts, with some very much more so, such as Hawkins'
Rail {Diaphorapteryx hawkinsi), the flightless Chatham Island
Duck, the Chatham Island Pigeon, and the Chatham Island
Bellbird. Further, of the 36 prehistorically known species, at
least seven were flightless (two ducks, four rails, and the
Chatham Island Fernbird; see Olson, 1990), and three more
were weak fliers (a duck, a snipe, and a parrot).
With the exception of an apparently new species of crested
penguin {Eudyptes, species undescribed; Figures 8, 9), no marine
taxa are known to have become extinct. The seabirds have
been affected, nevertheless, by the changes that occurred following
human settlement. Fossil remains of numerous species
of seabirds occur in large concentrations in many places, particularly
along dune ridges and promontories, on Chatham Island
and on Pitt. Few species of seabirds still breed on these
two larger islands; most current breeding colonies are restricted
to rugged, small, offshore islands or stacks. Fossil eggshells
and bones of very immature chicks indicate the presence of
former breeding colonies of a wide range of species. Radiocarbon
dating of bones indicates that some of these colonies were
occupied from at least 4500 years ago (NZA 1906, locality 18;
4300 ± 150 yrs BP=4545 CAL BP), and presumably much earlier.
Some colonies continued to be occupied into the period of
first human settlement, but there is no evidence of their persistence
into the European era and, indeed, little evidence of viable
colonies beyond about 300 years ago. These Chatham
Island/Pitt Island breeding species included albatrosses {Diomedea
epomophora sanfordi and at least one larger species);
mollymawks; shearwaters; diving-petrels; several prions; gadfly
petrels, especially the Taiko and another species, apparently
similar but not identical to the Mottled Petrel {Pterodroma inexpectata);
and storm-petrels.
FIGURE 8.—Skulls of Eudyptes spp. (dorsal views). Left to right: Eudyptes pachyrhynchus (MNZ 24546); Eudyptes, species
undescribed (MNZ S26908, PRM sample #6/89), from Maunganui, Chatham Island; Eudyptes sclateri (MNZ 18897). (Scale
bar=30 mm.)