MAN CAVE
Weesang Paaka with a tagged rainbow.
FISH WEARING BLING
STORY: JACOB LUCAS, NELSON
MARLBOROUGH FISH & GAME
T
rout adorned with coloured tags
are now found in a number of
waterways in the top of the south. Each
tag is individually numbered and come
in an assortment of colours, meaning
each release into a certain waterway
has its own specific colour and number
range. The trout are tagged at the
hatchery, and involves placing the fish in
anesthesia and performing a simple tag
insertion under the skin.
So why do we tag fish? Well, in this
region it is done so we can monitor the
effectiveness of our releases. We do this
through tag returns (when anglers catch a
tagged fish and tell us about it), and also
in our drift dive counts - an underwater
census of the fish population where
tagged fish are sighted by divers as they
42
August 2019
float down the river.
Tags also allow us to see what fish get
up to – where they go from their point
of release. We’ve had trout, for example,
which have travelled large distances from
their release point, and even some that
have navigated obstacles such as dams
– in some cases by surviving a drop over
the Branch River weir – a dizzying fall of
around 5 metres.
In the past we have also used small
microchips (PIT tags), which are inserted
under the skin and have a unique
number. Essentially these are the same
microchips that your family pooch is
sporting as required by your local council,
but are invisible to the naked eye and thus
require an electronic reader.
Last year one local angler handed in one
of these microchips, which he found in a
trout he’d just baked for dinner. Looking
back at our records we saw that this fish,
a hen, was caught in the same pool she
was released in nearly a decade earlier
– a tad unusual for rainbow trout which
are known to be fairly transient. She’d
certainly seen better days, which was
not surprising considering she was
nearing the maximum known age for a
rainbow trout – around 11 years old – a
remarkable feat for a New Zealand trout
having to navigate a lifetime in wild New
Zealand waters.
Many local anglers get a real kick out of
catching a tagged fish and will proudly
notify Fish & Game of their catch. In the
past few years we’ve had terrific feedback
from anglers catching our tagged fish in
a range of waterways, this is gratifying
on one level where that the angler has
derived enjoyment from catching the fish,
but on another level that the release has
worked well, and the hatchery trout have
adapted to the river environment.