Micro environment

[benjamin]

I have chosen to do my extended essay for the IB (International Baccalaureate), on the effects of various pollutants on small aquatic ecosystems. For my experiments I would like to use animals which are cheap to buy, reproduce quickly, and that don't raise any ethical issues (so invertebrates). I'ld also like to include at least two species each for producers (plants or algae), primary, secondary, and tertiary consumers, and detrevors, ideally the two species would be of varying degrees of hardyness. Also animals without a terrestrial stage are ideal. Any suggestions are appreciated.

 

[mark]

Are you saying you are gonna put some animals through stress to see how much they can take?

 

[ian]

I guess not some animals, but that seems like a lot.

 

[jeff]

How about daphnia? I mean that would be the obvious choice it seems. Or guppies if its water quality your interested in.

(Message edited by newtsrfun on December 16, 2005)

 

[joseph]

Daphnia seem to be the classic to use for this. Maybe some kind of aquatic insect larvae like mayflies.

I heard fish eggs(not sure of amphibian eggs) are not under the ethics issue(in the US at least) as long as they are not allowed to hatch.

 

[alan]

http://www.google.com/search?q=Daphnia+toxicology

 

[stipe]

Guppies would be your best option i recon.

 

[alan]

In the UK, using any vertebrate would violate animal control regulations. Use Daphnia.

 

[benjamin]

I will not try to stress the animals and I'm not testing anything's limit. I'm more interested in seeing which animals are more sensitive to pollutants than others, and how certain pollutants will upset the balance of an ecosystem. I was always considering daphnia, but I need something to eat them, that's an invertebrate and reproduces almost as fast. I'm thinking of planarians and pond snails for detrevors. Insect larvae unfortunately don't reproduce as quickly as I'ld like.

I'm beginning to think that maybe micro-organisms would be my best bet for creating an ecosystem including all the species I would like. Although it would be easier to have organisms I could see.

 

[mark]

Hydra love eating daphnia, reproduce quickly (at least in my tanks they do) and are sensitive to pollutants.

 

[john]

Planaria have been used as pollution bellwethers in several studies.