Welcome to the Midnight Collective Broadsheet 36
Actively supporting NZ’s endangered wetland bird
In a matter of days the
dune lake has gone from famine to feast, with a second small brood of
ducklings, being spotted. It is very difficult to identify the birds this year,
with last year’s thick grass still covering much of the lake, and we initially mis-identified
these. We thought that a kahu must have taken one of the original three
youngsters but did a rethink as these three emerged unscathed from the last few
days extreme weather.
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| Mum 1 with 3 ducklings |
We held little hope for
the surviving two ducklings until out they came, trotting onto the lake from the
blackberry. So we now have two
broods out on the water, and so far, at least they appear to be thriving.
 |
| Mum 2 defending her two ducklings from a mallard |
But then, just as we were
getting used to this development, a critically endangered Parera male turned
up. We think this may be the same one we spotted on the 17 July and his mate but can't confirm this though the relationships in this little community have begun to get very complicated.
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| Pure bred parera male - note grey head and green underwing |
Here, a recap on the
history of this conservation debacle might help. English mallards were
introduced into NZ around 1900, but when it was realised they were
interbreeding with parera (Pacific black duck) the practise was stopped.
Following sustained pressure from the gun lobby in the late 1930’s, however
mallards were again introduced from the US – around 30,000, which swamped the
local parera, and most of the parera population now have mallard genetic traits
– most, but not all. These birds can migrate to Australia and through the
Pacific, and from there back here, so what was a national disaster has now become an international one.
At the dune lake however,
we have regularly seen, usually between July and October not only solo pure bred parera, but
also pure bred pairs. And they are breeding here as well. We photographed a parera female with three adolescent young on the wharemauku in February. Meanwhile ducks
with predominantly parera strains (the males have grey heads and are often mistaken
for mallard females) have been raising families on the lake.
And here the plot begins
to thicken. Although this lake is set in the middle of town, these birds are
wild animals and their behaviours are quite different to the ducks you see (and feed) on your local ponds. It is this behaviour we have been trying to monitor to see if they
are maintaining a ‘cultural’ difference even while their genetic strains are
merging. Some evidence seems to point towards this. They usually keep in hapu
(small groups) of ten to fifteen. (We suspect these groups to be a closely
related extended family of siblings/cousins but cannot confirm this). The green headed males we
have observed seem to be intolerant of the grey headed males and over the last
three years we have seen these larger groups splitting into clearly defined
groups of green heads and grey. This doesn’t seem to happen in more domestic settings.
The females both mallard and parera, are colour
blind in this respect, but nor are they passive receptives of a males
attention. They will reject advances. What is curious however is that the grey headed males seem to stay
with the female, at least for a time, when she emerges from a nest with her
brood. This doesn’t happen with the green headed mallards, who the females are often at pains to protect their brood from.
We observed at the
lake with this current brood. The female with two chicks attacked a green
headed male when he made too close a foray to gain her attention but showed no
such aggression towards the pure bred parera.
They kept close together during resting, and when she moved he followed so this could be the original pair with the female re-emerging after a 3 week nesting period. The second mother was followed around
by a parera-cross male who was attacked by the same green headed mallard. This one wasn’t
having too much success with the girls and his frustration was showing. The
parera-cross was smaller than the mallard and didn’t put up a fight, eventually
managing to get away however, and back to the female who was quite tolerant of his company – where she had fled from the mallard.
There is certainly a
complex relationship story developing here and we will keep trying to track it,
though it is never the same day twice at the dune lake. They may have
disappeared next time we go down; and who knows how many nests are being
incubated beneath the blackberry. One thing is for sure – with the expressway
closing in its never a dull moment.
Track we were listening to
while posting this the ineffable Daphne Walker and Hoki Mai which is a song from WW11, calling the Boys back home...
Hoki mai e tama ma
ki roto, ki roto
I nga ring e tuwhera atu nei
Kei te kapakapa mai
te Haki te Haki
nga rangi runga Tiamana e
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