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Fish poo

(25 Posts)
Bags Mon 14-May-12 17:15:06

Why isn't fish poo regarded as pollution? Human poo in rivers clearly is. Just wondering and didn't want to post this on nightowl's birthday thread.

However, I can wish nightowl a happy birthday on this thread! cupcake

jeni Mon 14-May-12 17:16:05


Bags Mon 14-May-12 17:25:36

jeni, you said floating poo sticks (not Pooh sticks, but poo sticks) down the river was pollution. Fish do poos too. Just wondering..... wink

pompa Mon 14-May-12 17:26:55

I think you will find that in certain circumstances fish poo is a poo-lution problem, specifically where fish farming can produce abnormally high levels. Very large accumulations of human waste in a river is called New York.

On more serious note, in out region, huge numbers of swans and geese are causing serious problems on still waters, they both poo in the water which increases the nitrate levels and reduces oxygen levels, killing fish life. We lost all the fish in our trout lake when 400 + geese descended on it for the summer.

Bags Mon 14-May-12 17:27:24

Not to mention otters, water voles, rats, and other river water frequenters.

Anagram Mon 14-May-12 17:28:02

I suppose fish poo is environmentally-friendly, as fish only eat weeds and algae?

jeni Mon 14-May-12 17:28:50

Pike ear ducklings!

jeni Mon 14-May-12 17:29:27

Pike eat ducklings

Anagram Mon 14-May-12 17:30:54

I preferred the first version! grin

Bags Mon 14-May-12 17:32:49

All poo is environmentally friendly! It's called fertiliser. Plants aren't fussy what animal it has come out of.

We were told chicken poo is too strong to put straight on gardens so we put ours from the henhouse on the compost heaps. However, the stuff that got shat onto the grass got left and didn't seem to cause any harm. I guess it got rained in a lot of the time!!!!

Anagram Mon 14-May-12 17:34:27

OK then, Bags - why don't we put human poo on our vegetable plots?
Or dog poo?

Bags Mon 14-May-12 17:36:30

Because it needs time to break down any pathogens that might be in it. Human waste can be and is used as fertiliser perfectly successfully when it's properly composted. Have you heard of composting toilets? Check out the Centre for Alternative Technology.

Anagram Mon 14-May-12 17:37:32

Thanks, but I just wondered.....grin

jeni Mon 14-May-12 17:38:01

They do in some places, it's called nightsoil.its why you should not eat raw uncooked and unwashed fruit and veg in some places!

pompa Mon 14-May-12 17:41:16

Most fish are naturally carnivorous, eating other fish and small aquatic life. It's only man that feeds them fish pellets etc. Those that appear to browse on plant life are actually looking for small live food most of the time.

JessM Mon 14-May-12 17:58:47

I think pompa is spot on - it is a matter of concentration. Pollution is just a vague word, not a precise thing.

crimson Mon 14-May-12 18:16:09

Didn't human waste get taken down the Thames in barges years ago to be used as fertiliser?

pompa Mon 14-May-12 18:29:34

We live very close to Maldon, with it's flotilla of sailing barges. many of those barges used to take grain etc. up the Thames to feed London, they would return with used straw and manure for use on the fields.

Elegran Mon 14-May-12 19:05:11

I once read an account of an experiment that farmed fish in long tanks, about waist-high, and on top of the tanks were trays of growing plants for food. The nutrients from the fish helped the plants and vice versa. It needed pumps and aeration and so on, but i think no more than intensive fish farming would anyway. I wish I could recall more about it - it sounded like a good way to produce protein and green stuff at the same time.

nanaej Mon 14-May-12 19:40:00

Is pollution 'un-natural' waste? Most natural waste including poo will break down. Is it only manufactured goods (or their by products) that don't decompose that pollute . Or natural substances that are artificially concentrated?? Don't know just asking!

pompa Mon 14-May-12 19:51:22

I would class pollution as anything that adversely affects the balance of a natural system. This could quite well be a natural substance, but in an abnormal concentration, such as the swan/goose poo that I mentioned earlier. In a closed environment such as a fish pond or tank, too many fish will produce nitrate levels that the filter system cannot deal with, result - poorly/dead fish.

jeni Mon 14-May-12 19:58:03

The biggest problems are pathogens that contaminate the food. Vide bean sprouts last year!

pompa Mon 14-May-12 20:36:40

Interestingly the biggest polluters of our waterways and coasts are our own water authorities, they are prosecuted for pollution more than any other company or body. This is mostly due to raw sewage being discharged when their systems fail or cannot cope.

JessM Mon 14-May-12 20:42:17

Worldwide scale jeni I'd say the biggest pollution problem was human faeces contaminating water that people drink. It's natural and its lethal. Beats all other pollutants put together in terms of deaths, hands down, no contest.

jeni Mon 14-May-12 20:46:49

YES! Night!