Fish tanks as vectors for accidental introduction of exotic

[Stella]

http://www.conservationmaven.com/frontp ... xotic.html

(blog link)

About research by Ian Duggan from Waikato Uni.

I saw him present on this at the NZ Freshwater Sciences conference in 2008. He said there that he also sampled some pet shop tanks, which of course had higher numbers or exotic critters, and are of course the gateway.

I can't access the scientific paper, but the abstract is thus:

The aquarium trade has a long history of transporting and introducing fish, plants and snails into regions where they are not native. However, other than snails, research on species carried “incidentally” rather than deliberately by this industry is lacking.

I sampled invertebrates in the plankton, and from water among bottom stones, of 55 aquaria from 43 New Zealand households. I recorded 55 incidental invertebrate taxa, including copepods, ostracods, cladocerans, molluscs, mites, flatworms and nematodes.

Six were known established non-indigenous species, and eight others were not previously recorded from New Zealand. Of the latter, two harpacticoid copepod species, Nitokra pietschmanni and Elaphoidella sewelli, are not native to or known from New Zealand, demonstrating the aquarium trade continues to pose an invasion risk for incidental fauna. The remaining six species were littoral/benthic rotifers with subtropical/tropical affinities; these may or may not be native, as research on this group is limited.

A variety of behaviours associated with the set-up and keeping of home aquaria were recorded (e.g., fish and plants in any home were sourced from stores, wild caught, or both, and cleaning methods varied), which made prediction of “high risk” behaviours difficult. However, non-indigenous species had a greater probability of being recorded in aquaria containing aquatic plants and in those that were heated.

Methods for disposal of aquarium wastes ranged from depositing washings on the lawn or garden (a low risk for invasion) to disposing of water into outdoor ponds or storm-water drains (a higher risk). It is recommended that aquarium owners be encouraged to pour aquarium wastes onto gardens or lawns—already a common method of disposal—as invasion risk will be minimised using this method.

[BikBok]

my daughter observed that where we dispose the used water is where the grass is greenest and lushest! I feed my potplants with it too.

[DennisP]

my daughter observed that where we dispose the used water is where the grass is greenest and lushest! I feed my potplants with it too.

I second this.

[SamH]

I agree too. I usually dump my tank water onto the hedge outside the window, heaps bigger than the rest of the hedge.

[livingart]

always follow best practice

[Carlos & Siran]

We watered the tomatoes and water melon with it this year, heaps of tomatoes and our first ever water melon!!

[Caryl]

Boy do plants love aquarium water!

[bronze-dragon]

Boy do plants love aquarium water!

our cat loves it too :roll: he demands a cup full when he comes out to the fishroom with me.

[livingart]

our cat loves it too :roll: he demands a cup full when he comes out to the fishroom with me.

fish flavoured water

[kiwiplymouth]

The following is a list of responsible fishkeeping guidelines that I have posted elsewhere.

Feel free to add to the list.

Dispose of unwanted fish in the most humane method available (whilst obeying regulations)

Never introduce any exotic organism or plant to any area that may enter a waterway

Dispose of used aquarium water and any fish corpses far away from any waterway

Help educate the public of the consequences of an exotic introduction into our waterways

Prevent any cross breeding (hybridisation) of different species

[Ira]

Prevent any cross breeding (hybridisation) of different species

Unless they're a really cool hybrid. Like if you can hybridise redspot plecs and bettas go for it, I'll buy two off you...

[reef]

I prefer to dump water with ships ballast water direct into the ocean.

[livingart]

I prefer to dump water with ships ballast water direct into the ocean.

yes would be interesting to know how much comes in that way

[reef]

yes would be interesting to know how much comes in that way

most of it

[Ira]

yes would be interesting to know how much comes in that way

As far as marine pests go, within the margin of error of any survey...All of them. Now, freshwater pests the aquarium(And pond) hobby can be blamed for a lot of them, like koi and goldfish. Along with the fishing hobbyists for pests like trout...

[alanmin4304]

Many years ago the Japanese fishing boats coming into Lyttleton Harbour were reqiured to have a portaloo type toilet on the warf by the ship because the toilets in the boat were basically a pipe going out the side. The portaloos were then emptied into the Lyttleton sewerage system which discharged directly into the harbour around the corner a bit.

[livingart]

[Adrienne]

Interesting

I get my water for hatching bbs direct from the ocean so am probably bringing more organisms into my tanks this way than those who do not feed live bbs.

[David R]

All my water goes down the drain, there's no way I can discharge 800L+ per week onto my lawn or it would be a swamp!

[Ira]

All my water goes down the drain, there's no way I can discharge 800L+ per week onto my lawn or it would be a swamp!

You must have extremely poor drainage if that's the case.

[David R]

We do, its called clay. Over summer it wouldn't be a problem, but over winter the back lawn is a bog anyway.