Ecology of my Pond

The pond was originally dug c1860 by the second occupier of the property to provide
water for the horses. In recent years a ten inch pipeline was put in place to take the flood water which had previously spilled over into a furrow , Being too small to take the floods it overflowed and flooded around the house,, Unfortunately the pipe line became damaged and consequently when we arrived were were regularly flooded. Last year I fixed the pipeline and have made it so the dam now fills almost to the brim during the winter.


Over the past summer the pond is building up a sort of ecosystem. Its difficult to call it an ecosystem, or is just a collection of opportunists and some that have actually been put there?.A species of introduced frog has has started breeding and I counted about ten. Couldn't get close enough to make a real identification but I am sure they were the Green and Golden Bell Frog Litoria aurea from Australia where the numbers are decreasing but seem to be well established in New Zealand.There are three introduced species in NZ. The other at the top is the Southern Bell Frog Lotoria raniformis.
Two paradise ducks have now found the pond but only visit it in the mornings and take off in fright as soon as I approach.This duck is unique to New Zealand and has increased rapidly since the forests and bush were destroyed making way for pasture. The female with is white head and bronze colouring is more attractive than the male.Also known as NZ Shelduck Tadorna variegata but perhaps more a goose than a duck




Another visitor is the New Zealand fantail, a delightful little bird about the size of a sparrow but far more sexy. It appears not to be afraid of humans as it will settle just a few feet away on a branch and do a little pirouette before darting off over the water to catch a little gnat.


Well its midwinter now and there is ice on the pond in the mornings. Its too cold for my little friends and the frogs have hibernated. They will only come out when the water warms up and I'm not sure when that will be. After the pond first filled up the duck weed took over and covered the whole water surface, but with the help of the stormwater much was washed out and I have interfered and taken out a bit more.

Maybe if if I put in some plant eating fish the problem will be sorted out.Each plantlet disc of this particular species Lemna minor has only one root which is several cms long.
The patches of green duckweed can be seen clearly on the dam surface (top Picture)

Each plantlet is made up of three or four disc and each disc is made up of small compartments of air or bags of air enabling it to float. This picture is about life size. It is amongst the smallest flowering plants in existance. Another species present and associated with the duckweed is Azolla filiculoides(below) This tiny plant is actually made up of two living symbiotically together, each benefitting the other.The arrangement is not reversable as neither can live without the other.


The two are the tiny aquatic water fern and a filimentous blue green algae which aids the photosynthetic process and the production of energy for the fern but more importantly the fixation of nitrogen. .
Another species in New Zealand is Azolla pinnata and this can be distinguished by its feathery root.This one is not present in the pond.

Spirogyra is now forming on the sides of the pond.We used to learn about it in junior school biology.So here is a picture of it close up. I managed to photograph it with the aid of my microscope and digital camera.I'm quite surprised it worked.

Invasive species

My most recent interest is about the importance of invasive species and how these affect the concept of Gaia. If we consider that life actually created the earth as we know it today and we change that life we will also change Gaia, I call this invasion of the worlds ecosystems with plant and animals that are alien to the various ecosystems the 'Globalisation of fauna and flora'Many years ago I did research into how natural grassland became invaded with pioneer plants when the fertility status was changed by adding fertilizer.The pioneer plants were both broad leaved'weeds' and grasses.

This is how the grassland looked in pristine condition as it had evolved over millions of years with the dominant species (Plot 6) Themeda triandra









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After the application of heavy dressings of nitrogen fertilizer this is what it looked like.The weeds were seeds brought in by various means, probably by wind. The climax grassland is not easily invaded unless disturbed in some way or another. Mostly climax grasses disappear through selective over grazing, This has been brought about through intensive farming with cattle and sheep with the erection of fences and the complete absence of native grazers. In the above case the climax grasses actually died out leaving bare patches before the invading plants came in so they were not out competed.

Thinking it through

Ecology has been my interest from when I was very very young. It still is,but recently my interests have been enlarged to include evolution, DNA , GAIA. and Consciousness. How does it all fit together? I do not think of the Earth is a living organism in the normal sense but it is the best way to think of it. Evolution is a fact not just a theory and DNA research confirms it. Consciousness remains the real problem but my feelings are that it's evolution started when life began and has evolved with it. Anyway that's a start.