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General Discussion

COOK. During which months were rata trees eaten?

FITZGERALD. In the Orongorongo Valley northern rata Meterosideros robusta was eaten in all months of the year. Over the whole year this species comprised about 30% of the diet.

CHARLESTON. Do they more than accidentally eat insects? Having kept the old possum I found them willing to eat almost anything and they just loved meat.

FITZGERALD. Yes. that is right, they will eat practically anything. Dr Ben Bell has done some work on possums eating puriri moths. When these moths are in season he found them taken in large numbers by possums when attracted to a light. He had the moths analysed and they had a high lipid content. Mick Clout's example I cited was not just a case of a few odd larvae in the gut -the dipterous bibionid larvae were there in considerable numbers, something like 1,800 in one stomach. To a very large extent these larvae came through the gut intact.

PEKELHARING. Is there totara Podocarpus totara in the Orongorongo Valley and, if so, do possums eat it?

FITZGERALD. Yes, it is there and they eat it, but it is not in their first 14 choices of tree species.

BROCKIE. Mistletoes were once widespread through New Zealand but have been disappearing at an alarming rate. One species Trilepidea (Elytranthe) adamsii was confined to the Coromandel district and is now thought to be extinct because possums have eaten it out. This is the one and only New Zealand native species that seems to have become extinct on the mainland, and possums seem to be the culprit. It looks as though other mistletoe species are heading in the same direction and very rapidly.

FITZGERALD. This is an interesting point. Dr Given has produced a recent paper^* on rare and endangered plant species and it would be worth checking - presumably you could make some intelligent guesses about other species likely to become extinct like the mistletoes.

ANONYMOUS. The reverse is reported from South Australia where mistletoe is alleged to be spreading through the lack of possums.

FITZGERALD. I think Sir Charles Fleming noted that pollen analyses indicate species such as Meterosideros were quite widespread in parts of Australia, but no longer occur there.

MIERS. Kamahi and fuchsia were also in a similar category in Australia.

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