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Efforts to re-establish Brown Teal populations by releasing
captive reared birds first started in 1968 when the NZ Wildlife
Service released 10 pairs of Brown Teal onto Kapiti Island.
These birds were a mixture of both captive reared and wild
caught birds. Some thirty years on Kapiti Island still supported
a small but self sustaining population of Brown Teal.
The population was given a boost in 2001 when a further ten
pairs were released onto Kapiti Island.
Over recent years successful breeding of captive reared Brown Teal released on to Mana Island, Kaori Sanctuary, and Warrenheip
have been confirmed.
Between 1977 and 1983 320 Brown Teal reared by Ducks Unlimited
members were released onto coastal lagoons in the Manawatu
area of New Zealand. These birds adapted well to the wild
and successful breeding was recorded on a number of occasions,
but with widespread duck hunting in the area, together with
a whole suite of predators to contend with, this population
also declined. There are, however, still regular sightings
of Brown Teal frequenting the Waikanae Estuary, which is on
the mainland opposite Kapiti Island.
We now appreciate that nothing whatever had been done in
the Manawatu to reduce or eliminate the reasons why the original
Brown Teal in the area, which were once present in vast numbers,
had disappeared. But in those days everyone was on a learning
curve and in 1983 it was decided to try another area in the
North Island with a release of captive reared birds. This
was on Matakana Island in the Bay of Plenty, where 64 teal
were released, but this too was not a success and a decision
was made in 1984 to move the release programme to Northland,
where c500 Brown Teal still survived, in an effort to stabilise
the declining Northland population.
A considerable amount of Brown Teal habitat protection, creation
and enhancement work had been carried out in Northland by
the NZ Wildlife Service and from 1984-89 a total of 494 captive
reared Brown Teal were released onto five different wetlands
in Northland.
On-site pre-release holding aviaries were erected at two
sites and various experiments took place in an effort to determine
the best release technique and what was the most suitable
time of the year to release the birds, but no conclusions
were reached.
The totals of Brown Teal released into the wild between 1978
and 2001 were just over 1,500, with close to 1,000 of these
being released into Northland.
In Northland none of these Brown Teal were released into
areas where Brown Teal still survive and only in four instances
have they been released into areas recently vacated by Brown Teal.
A relatively insignificant amount of monitoring of teal released
in Northland has taken place; such follow-up work must be
an intrinsic part of the programme.
From the release exercises up to the year 1997 it would be
very easy for a conclusion to be reached that - no-one really
knows what they are doing! That may well be true, but a lot
of good people where trying to create miricles without alot
of money or support.
It is now encouraging that currently there is certainly a
more cohesive approach to releases being taken which is based
on sound science, so at least we can find out excatly where
we need to improve. Birds are now only released into either
predator minimised or predator free areas, and a representive
sample are transmittered and monitored to now truley understand
what is happening once your captive babies once released.
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