Chlidonias,
I've read that NZ's only native mammals are two species of bats and saw on Attenborough's Life of Mammals that they (one or both) do a lot of feeding on the ground...
Can you elaborate on these species..?
How has 1080, previously mentioned and predation affected them..?
How is their status in the wild and are there any in captivity..?
Thanks in advance...
NZ bats are awesome. To be particularly picky, they are NZ's only native LAND mammals because of course we also have lots of cetaceans and several pinnipeds. There actually used to be three species of native bat: the long-tailed and lesser short-tailed are still with us, but the greater short-tailed is now presumed extinct. Subfossil remains show that all three were once found all over NZ but by the time the greater short-tail was discovered it was restricted to islands off Stewart Island (and at that time considered to be just a very large subspecies of what we now call the lesser short-tail). The last known population was on Big South Cape island off Stewart Island but disappeared (along with most of the birds and other wildlife) once rats became established there in the late 1960s. None have been seen since. Muttonbirders' kids remembered how they used to go and look at them in the caves and the muttonbirders would find them roosting in the muttonbird burrows. Its remotely possible that there are a few still on some small islands in the vicinity but it is unlikely.
The lesser short-tailed bat is found in three subspecies: the kauri short-tailed bat in Northland and on Little Barrier Island; the volcanic plateau short-tailed bat in (lower) Northland, the central North Island and Taranaki; and the southern short-tailed bat in Nelson, Fiordland and Codfish Island (off Stewart Island; where the kakapo are). The total population is about 50,000 which sounds like a lot, but 40,000 of those are in the central North Island alone.
The long-tailed bat is widespread but probably declining. It is no longer found down the east coast of the South Island (the last ones found there were in Geraldine but I think they've gone now). I don't know population figures.
The scene in the Life of Mammals of the short-tailed bats burrowing through the leaf litter after prey was fantastic. They also burrow into the rotting wood of their tree roosts. When in flight they stay low to the ground. The long-tailed bat stays high so they are generally fairly easy to distinguish when seen. (In the hand they are very distinct: the long-tailed bat has a long tail and short ears; the short-tailed bat has a short tail and long ears). Their differing habits are probably the main factor in their survival rates. The short-tailed is easy prey for cats because they are on the ground a lot and fly low.
I really doubt 1080 is of any concern at all for bats. The ones on Kapiti that were held in aviaries until poisoning on the island was complete, was probably just for the sake of making sure nothing happened to them rather than for any real perceived threat. It could be possible they may take the baits, being ground-feeders, but unlikely. (Just as an aside, there is a native parasitic plant called the wood rose which is apparently the world's only ground-flowering plant that is bat-pollinated).
I know short-taileds have been kept in captivity at Mt. Bruce (before being originally introduced to Kapiti) and they proved easy to keep, as may be expected for a ground-dwelling bat. Apparently there will be some at Auckland Zoo's new native area:
Rare native bats bound for Auckland Zoo | NATIONAL | NEWS | tvnz.co.nz
The following link is also interesting, being from Mt. Bruce:
More about New Zealand lesser Short-tailed bat pekapeka- Mystacina
Note that it says in there that short-tailed bats are related to South American bats, but that is actually an older idea which has been more or less disproved from fossils found in Australia showing that a common ancestor came from there instead (short-tails probably came to NZ from ancient Australia around 30 million years ago). The long-tailed bat on the other hand belongs to a genus of Australian bats and must be a fairly recent colonist of NZ.
The short-tailed bat has a commensal wingless fly that lives on the bats and in their roosts. There is also a song called "Bat Fly" by a NZ band called "Fatcat and Fishface", which is about this fly (my girlfriend really likes the song). Listen to the lyrics!!! So cool.
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