I want Newts

[shireknight]

Hi forum members,

I have loads of Frogs but I would like some Newts please.

My pond is about six years old, I saw a Newt in it in the very first year but I had fish in there then and the Newt quickly vanished again. My fish all died off a good two years ago and all it contains now is Frogs, pond skaters and the odd Dragonfly.

It is a 1000 litre plastic pond with a lilypad at the end, aquatic plants top left and right and a fairly large waterfall middle top. Behind the aquatic plant top left is a pile of small slate like stones that Newts should be able to easily climb up to allow them to exit the pond.

I have a pump which feeds the waterfall however it doesn't have a filter inside and is used purely for the waterfall and not filtering the water so if a Newt did get sucked into it the worst that would happen is it would find itself at the top of the waterfall and have to climb back down again.

Personally I think it's an excellent pond for Newts however they don't seem to agree, is there anything I can do to promote it to attract Newts please?

[Dogghound]

Encourage as much native aquatic vegetation as you can so you get between 50 and 70% pond cover. I would personally scrap the pump/water fall if you dont have any fish. Dont put any more fish into the pond. Build up the habitat around the pond with dense vegetation and log piles. If you have had them in the pond in the past then its likely that there is a population close to the pond so it increases the chance of re-colonisation. Once/if you get an established population of newts you may find that you lose your frogs or the number breeding in the pond decreases.

[wanlock dod]

It might be worth considering why the fish died. A check of the water quality with a few simple test kits might be worthwhile. I am not sure what water quality conditions nets prefer, but I doubt that they would bother with anywhere where the water conditions were not entirely to their liking. Just because you can't see it doesn't mean that it isn't important.

[Billabong Karen]

If you could post a photo of your pond it would make it easier for us to give pointers on how to make it more 'newt-friendly'!

[Dogghound]

Originally Posted by wanlock dod

It might be worth considering why the fish died. A check of the water quality with a few simple test kits might be worthwhile. I am not sure what water quality conditions nets prefer, but I doubt that they would bother with anywhere where the water conditions were not entirely to their liking. Just because you can't see it doesn't mean that it isn't important.

Smooth newts (which are most likely to be what the OP will get) like neutral to alkaline water. Excessive pollution or acidification is not tolerated however than can withstand a wide range of water qualities including small amounts of pollution. I suspect if frogs are breeding in the pond then the water will be fine. Fish often die over the winter as they dont get enough oxygen for a variety of reasons.

[wanlock dod]

Excessive pollution or acidification is not tolerated however than can withstand a wide range of water qualities including small amounts of pollution........ Fish often die over the winter as they dont get enough oxygen for a variety of reasons.

In my experience it is not possible to generalise about the pollution sensitvity of any aquatic species, although in many cases people only consider the combination of ammonia and BOD that is typical of sewage effluents. Newts are apparently able to breathe atmospheric oxygen, so may be able to tollerate low oxygen conditions better than many aquatic species.

A lack of oxygen sounds unlikely as the main cause of fish kills in winter given the much higher solubility of oxygen in water, and much lower oxygen consumption rates in the colder conditions.

Newts may well need suitable terrestrial habitats, as well as aquatic ones, and they would also presumably need a suitable route to the pond from where ever they are already. I can imagine this being a key factor in determining whether newts of any kind will find their way to any particular waterbody.

[Dogghound]

I wasnt trying to cause an argument or being critical of your post!

Originally Posted by wanlock dod

In my experience it is not possible to generalise about the pollution sensitvity of any aquatic species,

I can't comment on your experience, but amphibians are quite sensitive to pollutants as their skin is very permeable. Agro-chemical and chlorine based pollutants can have severed impacts on populations locally. Acidification has also lead to population collapses of smooth newts and is still a factor influencing them and great crested newts in some areas. I have seen pools in industrial sites lose populations due to this. Smooth newts are less sensitive than some of the other species and can tolerate low levels of organic pollutants. If you poured a ton of slurry into a small pond you would probably lose them though.

Regarding pollution sensitivity of aquatic species you can quite clearly generalise on it as a huge number of species of plants and animals can be used to analyse and indicate levels of pollution. Aquatic invertebrates are perhaps the best example of this. If you study the fauna up stream from a pollution source it will be totally different to down stream. For a basic example caddis, mayfly, alderfly etc show unpolluted water and Eristalis, Helophilus, leeches, tufix etc show polluted water. You can also use this whilst conduct amphibian habitat suitaility indexes, in which a lot of the criteria are subjective to pollution sources.

Originally Posted by wanlock dod

although in many cases people only consider the combination of ammonia and BOD that is typical of sewage effluents.

Who like? Nitrate input from sewage, fish, fowl etc causes eutrophication, unless it is severe smooth newts can live in quite nitrate rich ponds. Although GCN and Palmate tend not to be as tolerant. GCN struggle even with large amounts of wildfowl effluent. Highly eutrophic water will result in aquatic macrophytes dieing reducing invertebrate prey and egg laying material.

Originally Posted by wanlock dod

Newts are apparently able to breathe atmospheric oxygen, so may be able to tollerate low oxygen conditions better than many aquatic species.

Newts mainly surface to take oxygen and I agree they can tolerate low levels. However ponds with low oxygen which are in a poor condition have less aquatic macrophytes and less aquatic invertebrates, so are off less value. Additionally metamorphs are completely dependent on dissolved oxygen during their aquatic stage.

Originally Posted by wanlock dod

A lack of oxygen sounds unlikely as the main cause of fish kills in winter given the much higher solubility of oxygen in water, and much lower oxygen consumption rates in the colder conditions.

It may sound unlikely, but I wasnt just making it up.

I the issue with a frozen pond is that detritus in the bottom of the pond decomposes and uses oxygen, the plants still produce oxygen and the water contains some dissolved oxygen but when this rate is slower than the rate of decomposition and respiration (using oxygen) of organisms in the pond then the oxygen level reaches a critical point in which death occurs. Fish not only use up oxygen but they also produce lots of waste which contributes to the drop in oxygen (i.e further decomposition, nitrate input). Prolonged thick ice also inhibits photosynthesis which further reduces oxygen. Amphibians require less oxygen than fish as they can drop there metabolic rate lower than a fish, so fish (especially large ones) feel the affects first. Species like frogs can suffer though, a lot is dependent of the actual pond.

[wanlock dod]

Dogghound,

Such discussions and exchanges of views are always interesting, although I would say that anything posted on a forum such as this needs to be treated as being similarly reliable to "some bloke down the pub told me..."

I have seen several examples where EPT taxa have been present in numbers far above what would be expected (from RIVPACS) in heavily polluted streams, regardless if the level of pollution (although these were not polluted by sewage). Similarly, an EA study showed that EPT were less sensitive than the community as a whole in a study on mining impacted sites (again, no sewage). Thus making such generalisations about pollution sensitivty is not always correct, although I would agree that your observations are most likely consistent with sewage related contamination. The point is that there are many different types of pollution, and they do not all affect all species in the same way. Many people (not necessarilly yourself) seem to assume that the BMWP score for a species will indicate its relative degree of sensitvity to all pollutants, but this is simply not the case. I know of several cases where snails are considered to be by far the most sensitive organisms for example.

I had a look for ecotoxicity data on newts. I didn't find any although I know that there has been interest in amphibian sensitivity over the past decade or so, particularly with respect to some herbicides. I am not aware, however, of any cases where amphibians have been identified as the most sensitive group of species for any environmental quality standards (although my detailed experience is probably limited to only around a hundred or so different types of chemicals).

In the case of the fish deaths you mentioned, I would be particularly interested to know whether you actually confirmed that the levels of dissolved oxygen were too low for aquatic life (and that there were no other relevant toxicants present), or whether it was simply assumed to be the case. Certainly your mechanism seems plausible, although demostrating cause and effect is something that is possible only very rarely, and probably never without supporting analysis.

I would encourage everybody to consider every individual situation with an open mind, whilst bearing in mind that certain groups or species could be sensitive. If we assume that some of these generalisation will always be true then sooner or later we will find we have got it quite wrong.

I seem to have spent most of my career so far standing between chemists and biologists trying to make them see that whilst they both have a fair point, neither of them can resolve the whole issue on their own (and I'm still losing that one).

[Tringa]

Wish I could help, but in my limited experience, you have a pond - you get newts.

Although our pond is in good nick now, last year it was poor. We had about nine goldfish that had been there for about 5 years. It was cloudy and the bottom 6-9 inches were smelly sludge and yet when we emptied it there were newts, which we put under bushes. They and the frogs came back after we had refilled it (the frogs were getting back in as we were trying to keep them out) and this year we have seen newtpoles and adults.

One thing that may have an effect is your pump. Although you said it circulates the water without filtering, if a newt gets caught by the inlet it will have to go through the pump before returning to the pond. Our pump killed a few newts until we put it (it is a submerged pump) in a bag made from a net curtain.

Sorry I cannot provide a solution, but I was very surprised that once we made a pond, the newts just appeared.

Wanlock mentioned the rest of your garden. What is it like? Ours is a fairly untidy mess with lots of places for things to hide. However, unless your garden is pure tarmac with a pond in the middle then I think newts would find somewhere to live when out of the water.

Dave

[shireknight]

Thanks for the replies, I shall take a couple of pictures tomorrow and post them up.

I built the pond deliberately as a wildlife pond and made the mistake of thinking that fish were a part of the natural environment so started with 7 fish a mix of Goldfish and Shubumkins. They slowly started disappearing and my neighbour mentioned he had seen a Heron in my garden one day while I was asleep (I work nights)

I have a water testing kit and I never could find anything wrong with the water quality and at one point I even found a brand new baby fish however over time they still kept vanishing and then the remaining ones started dying with no signs that I could see that anything was wrong.

The baby who by now was a good two years old and about 6 inches long was the next to last to die which really hurt me and a month or so later the last adult who was huge started floating on it's side (would right itself and swim the the bottom if I touched it though) and eventually died a few days later.

To this day I don't believe that water quality was an issue however I think I know what happened.

One day about a year or so before the last fish died I found a Pineapple chunk next to the pond, I live alone so I know it wasn't anything to do with me. Now my neighbours who are in their late seventies had regularly asked how my fish are and like you do with your neighbours I always entered into conversation about my pond and never thought anything of it. However shortly after the last fish died the neighbour asked me what I was intending to do with the pond now it was empty and I just casually mentioned that I was going to do nothing with it because it was supposed to be a nature pond and that the fish were an accident in the first place and should never have been put in there.

At this he went ballistic and launched into a ranting tirade about how my waterfall attracts loads of birds that sit on top of his conservatory all day making a mess that he has to pay to have cleaned off and that he would lodge a complaint about it with the council.

I was completely taken aback at this because until now (some six years or so) we had never so much as had a cross word and he had never even mentioned any bad points about my pond before. The upshot of all this is that I suspect he killed the fish slowly over time by throwing stuff into the pond