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92
DEPTH
(cm)
0
50
60
100
120
140
150
180
190
200
210
* NZA 1948
* NZA798
* NZA 2778
* NZA 801
* NZA 800
* NZA 1989
ggbil
Uneven cave sediment-fill surface
10-50 cm dark-brown organic soil, much disturbed, with
bones of sheep (Ovis) and rat (Rattus)
10 cm orange-brown sandy silt, much disturbed, with bones
of sheep and rat
Surface level of undisturbed sediment
10 cm brownish-cream, homogeneous detrital sand rich in
avian bones
30 cm creamy-white detrital sediment, predominantly
bryozoan fragments and echinoid spines. Rich in creamcolored
avian remains and landsnail shells
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
20 cm white detrital sediment with fewer 'fines' than the layer
above. Rich in avian bones - pale whitish-cream except near
walls and intruding roots where they have become orange
stained
20 cm darker brown/cream sediment with greater clay
fraction. In main cave fewer bones than in the layer above,
but dense accumulations in several side tunnels
10 cm rounded, creamy-white, limestone cobbles(up to 70 mm
diam.), interspersed with marine shells (Cliione)
5 cm hard, moist, fine, brown clay/mud with an orange (ironstained)
upper surface
20-30 cm large, angular slabs of Te Whanga Limestone with
an intermediate layer of cobbles and rounded boulders (to
150 mm diam.)
10 cm - air gap where percolating water has washed away
finer sediments
20 cm of friable white-yellow-brown sand, with lenses of
orange-brown sand, and a moist water-scoured upper surface
Solid rock floor of Te Whanga Limestone
(essentially at the contact between the Te Whanga Lst and the
overlying Te One Lst in which the cave has developed)
FIGURE 6.—Schematic stratigraphic section of sedimentary deposits within Te Ana a Moe Cave (locality 16).
Locations of radiocarbon-dated samples are marked by asterisks (*) and are identified by their Rafter Radiocarbon
Laboratory reference (NZA) numbers.
range of taxa are represented in the deposits, in total many
thousands of bones from hundreds of individuals, the following
species predominate in the assemblages: Chatham Island
Rail {Gallirallus modestus), Dieffenbach's Rail, a merganser
{Mergus, species undescribed, Figures 12-14), Chatham Island
Fernbird {Bowdleria rufescens), Magenta Petrel, or Taiko,
Fairy Prion {Pachyptila turtur), and Common Diving-petrel.
One particularly important find was that of an almost
complete individual skeleton of the flightless Chatham Island
Duck, Pachyanas chathamica Oliver (1955) (Figure 7). Bones
were more abundant in the lower levels (particularly in the
2300-3900 CAL BP strata), but species composition varied
little with depth. The fact that the youngest dates obtained for
in situ faunal material were ca. 1150 CAL BP (e.g., NZA
1948, locality 16) is taken to indicate that at about this time,
when the infilling sediment reached the level of the single
walk-in entrance, the cave ceased to be an effective pit-fall
trap for birds.