Improving the Declining State of Whitebait
If you listen to old-school whitebaiters, tales of taking
away full buckets of the bait are not unheard of. However, nowadays you would
be doing extremely well to be catching those types of volume, and despite
fluctuating catches from year to year, most whitebaiters would agree that today’s
catches are far less than they have been in previous times.
What is whitebait?
Whitebait is not one single kind of fish. The term whitebait is a
general term used in many countries to describe small freshwater fish that are
tender and edible. In New Zealand it describes the juvenile forms (around 4–5
centimetres long) of five species of the fish family Galaxiidae. These juvenile grow up to become inanga,
koaro, banded kokopu, giant kokopu and short-jawed kokopu. These native
fish are known as galaxiids, due to the Milky Way-like galaxy patterns found on
the adult fish, in particular the giant kokopu.
Problem Definition
As mentioned, there are five species of juvenile fish that
constitute whitebait. Of these, the large the inanga makes up the largest
portion. So what about the other four species? well the other four species are
now considered to be seriously threatened due to a number of contributing factors.
Predator problems endanger the survival of Inanga:
·
Trout
·
Shags
·
Eels
·
Humans with nets
However, the pollution of our waterways and the destruction of whitebait
habitat are considered more of a concern. So perhaps these first few threats
(trout, shags, eels) are logically expected given they are part of nature and
possibly make up a life cycle, which might be expected to occur. The human on either
side of the riverbank with his or her net however would not be part of this
life cycle, although their intentions are the same of the shag, trout and eel,
which is to feed their bellies, with what is regarded in New Zealand as a delicacy.
So what else is causing havoc in the life of a whitebait then? Well I’m
glad someone asked, because without defining the problem correctly it is
difficult to understand how to solve the problem within the context of IEM
(well so I’ve heard!).
Defining the Problem correctly
The pollution of New Zealand’s water (from agriculture)
and the destruction of whitebait habitats are perceived
to be the major concerns with regards to the declining whitebait population,
other than the human net of course. It seems only logical that a clear link can
be made between the decline of whitebait over the last 50 years and
agriculture, particularly dairy farming considering that this has been a major
growth industry in the last 20-30 years (coincidently over a similar period to
the decline of whitebait).
The whitebait seeks habitats upriver where there is still plentiful
indigenous forest cover. The issue with agriculture especially dairy
farming is that a lot of this indigenous cover is being removed and to add to
that stock are allowed to roam the banks of lowland streams where their hooves cut
up the riverbanks while their grazing of the riverbanks reduces the streamside
vegetation. Something to take into consideration is that the number of
cows in New Zealand has increased to more than the human population.
Impediments in our waterways notably culverts and dams that have been introduced
in many rivers and streams throughout the country to benefit human civilisation
is considered another major problem for the survival of whitebait. Impediments in
our waterways restrict the journey of fish to be able to move upstream to spawn
and therefore reduced the juvenile fish (whitebait) travelling downstream. Another
problem that may be considered is that there is a lack of understanding about
the spawning habitats of all the whitebait species. Of the five whitebait species,
only the spawning habits of inanga are fully understood. This may be another
reason why whitebait is declining or the population rates fluctuate from year
to year.
Issues:
Whitebait spawns on a spring tide, by laying eggs in the vegetated areas
next to streams. They need cool, moist, protected areas, because the eggs
remain there until the next spring tide when they are picked up by the tide,
hatch into the stream and wriggle out to sea.
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| Retrieved from: http://www.doc.govt.nz/publications/parks-and-recreation/activities/fishing/whitebaiting/whitebait-regulations-all-nz-except-west-coast/whitebait-facts/ |
The modification of riverbanks (for urban purposes of because of
livestock) and livestock grazing up to the edge of streams wrecks the
whitebaits habitat, and leaves the vulnerable whitebait eggs out to dry, whilst
the culverts and dam infrastructure restricts their movement to spawn at all. The
other big problem for whitebait is the pollution to waterways from agriculture.
Freshwater fish struggle to survive in polluted waterways - they need
clean, high-quality rivers to thrive. In most of the country, the quality of
river water has been declining because of run-off from agriculture and urban
land uses.
A key
concern for Maori in the Waikato is the loss of whitebait from the lower Waikato
River because it is seen as a historic cultural fishery. The presence of large
numbers of whitebait in the river has also been viewed as an indication what
the health of the river is. Recovery of the whitebait fishery is therefore an
important restoration goal for iwi in the Waikato River.
What is already happening?
The New Zealand whitebait connection organisation is an example of how the declining
state of whitebait in New Zealand can be reduced using an integrative approach.
The NZ whitebait connection is essentially a community based environmental
management group that is taking a bottom up approach (from the grass roots)
providing knowledge about freshwater ecology and the effects of land management
on freshwater quality. Acknowledging the causes of an issue can be seen
as one of the first steps toward making any improvements to the issues
management.
Waikato Environment and Scientists have come up with a solution to
overcome the spawning issues posed by dams and culverts in New Zealand rivers
purely by studying the existing behaviour of the fish and understanding the
system. The solution is rope: picture
Yes, seriously the use of rope for fish to climb up is a successful
answer that these scientists have come up with, check out the video below to
learn for yourself!
Recommended solutions:
·
Whitebait regulations could be revised, meaning
licences for catching whitebait would be needed. This however does not address
the problems identified earlier this is just a response to take less of what is
already considered a depleting stock because of more fundamental reasons.
Using an integrated management approach, I would
recommend the following:
·
To be able to change the declining state of water
quality, reduce the impacts on habitats and overcome the barriers of structures
in rivers preventing the spawning patterns of whitebait a number of IEM
approaches need to be implemented.
·
Central government action is needed in particular
to be able to have any attempt at reducing the dominating effects of
agriculture on the quality of the water in our rivers and ultimately the
survival of not only whitebait but also many other aquatic species. Multiple tiers
of government could be implemented here using a top down approach.
·
Goals need to be set in terms of nutrient run off,
and rules need to be established regarding the access of stock to open waterways,
both of which are having major impacts on the quality of whitebait habitats.
·
The scope and the scale of the problem in a
nationwide context needs to be identified so that the question of what subjects
should be included in the initial efforts to reduce the effects on the declining
population of whitebait. The historical nature of whitebait trends and
fluctuations also needs to properly understood to figure out long-term goals
and objectives.
·
Although I have already mentioned the idea of
community based environmental management as a solution that is currently being
undertaken by the informal group NZ whitebait
connection. None of this knowledge or support will be useful without
increasing community awareness or creating options for participation and
collaboration between all stakeholders and institutions that have an interest
in whitebait or are having an effect on its existence. Although a bottom up approach may begin to drive awareness
of the issue it may have little effect on major industry having effect on water
quality therefore a top down approach would be necessary as well (multi level
governance).
- · Restoration can only be achieved if the factors responsible for the decline in the fishery can be identified and reduced. The agricultural industry is therefore a key industry that needs to be involved in the participation and collaboration process to improve the declining state of our waterways, not only to protect whitebait but every other ecosystem reliant on freshwater streams and rivers, and to provide for a sustainable future.
- · Pressure points need to be identified. Spawning habitats for inanga are very limited in rivers and is therefore a pressure point in the life history of inanga, restoration of spawning habitat in the Waikato River is clearly required. Not only would this be required in the Waikato, but it would also be a trend that needs addressing all over the country. To address this, the consultation needs to occur with the industries that are affecting the environments; this may even require government intervention to regulate the use of and access to riverbanks. Improving the protection of whitebait habitats for spawning purposes may therefore be a short-term objective to produce results in the long term.
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| Who wants to see this disappear? I know I dont!! |
References:
Carl Walrond.
'Whitebait and whitebaiting - Whitebait in New Zealand', Te Ara - the
Encyclopedia of New Zealand, updated 1-Mar-09
URL: http://www.TeAra.govt.nz/en/whitebait-and-whitebaiting/1
URL: http://www.TeAra.govt.nz/en/whitebait-and-whitebaiting/1
‘In our Nature’ – blog by Nicola Toki,
retrieved from URL: http://www.stuff.co.nz/national/blogs/in-our-nature/7393261/Why-our-whitebait-are-at-risk
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