Hi All

I recently moved house, my new home came with a very well established garden pond, its is varying depth and is full of hide holes and vegetation.  This spring I had plenty of frog spawn and plenty of Palmate newts visit to breed, huge dargonflies emerged and returned to lay also.  But..my dear son (bless him) has introduced native fish to the pond, not a bad idea of a natural pond was my first thought. These  inlclude Rudd and 'Perch' there are just 3 perch up to half a pound or so, they are kept bellies full but it leads me to my question.

I read somewhere that the amphibians can 'sense' the presence of the predatory fish and may refuse to breed or even enter the pond now.  Is this true? will my Phibs return? will the Perch have to go? Perch are really good to keep as they quickly become tame and seem quite intelligent (for a fish) and like to be fed by hand, so much more interesting than Koi, so I dont want rid of them, but its them or the amphibians, who were there first.

Help?

Well if you want to make sure that young newts are predated effectively then Perch are the fish for the job - it is only natural - I dont think that any research has been undertaken into whether palmate newts will avoid ponds with fish - the research was using sticklebacks and crested newts and it seems the evidence suggested that cresties will avoid ponds with fish

Likewise your frog population will potentially decrease in number as they may also avoid predatory fish - I know it has been suggested that they will avoid crested newt ponds

So you will have to wait and see next spring

I know of a pond in Essex where a small population of rudd live with palmate newts - hundreds of them - I suspect that the larva of the newts are not as vulnerable to fish predation as the crested newt larva -

Also be careful about admitting moving native fish around the UK - you cannot do this I believe without a license from EA - unless you bought them - if the fish came from a private fishing lake then this can be considered as 'theft'

so it would be best to leave the fish in the pond - i.e. do not move them back to where they came from

Anyway I really like Perch they are great fish

what do you feed them on?

Jon

Thanks Guys

Jon, I will have to live with the law now I guess, the perch came from a farm pond with permission, but if that is illegal, I am happy to face the consequences, as a British citizen I am accunstomed to being 'nicked' for something slight whilst I watch the crims run free :). I did do a quick search and from what I understood, the common Perch is the only member of the Perch family in Britian that does not require a license, I could be wrong of course, I am an Engineer who only dabbles with mother nature. Though I am becoming a little known refernence on the Perch, as many an Angler stops me at the shop where I get some food for them wanting to know when, where and the fish eat etc. Word has got around I guess.

The Perch are fantastic to keep in the pond, I keep the water quality very well and its crystal clear most of the time so as a mini observatory it is very good.  The Perch have become quite tame, as I approach the pond edge at dusk they come to greet me, by hanging vertically with mouth just millimeters from the surface.  They will take  offerings from my fingers, not gently of course, that isnt in thier nature, but I am never bitten, not that it would be uncomfortable if i was.  

 As for food, well, mainly frozen prawns supplimented with frozen mussels (both defrosted of course) maggots and worms are added to vary the intake as and when they are available.  Interestingly, the Rudd spawned this year and a shoal of up to two inch fish occupy the surface but the Perch do not bother them, I assume this is because thier bellies are full.  In all very interseting animals to watch, to see them stalk the other fish is wonderfull.  In my opinion it is Britains most interesting fish, both in its habits and its appearance.

Martin 

Hi Martin

I am sure that a license would probably be required - as any movement of any fish needs to be licensed by the EA - but hey what is done is done I suppose or maybe garden ponds arent covered.

I am intending to build a new pond myself and I am tempted to make an extra big one so I could maintain a few perch.

Perch are also very good to eat - as good as trout some people say so maybe I could put a few on the bar bie when they are big enough though I probably wouldnt be able to do that to them once I get attached to them

Jon

http://i28.photobucket.com/albums/c207/martingillman/IMG_0965.jpg - http://i28.photobucket.com/albums/c207/martingillman/IMG_096 5.jpg

the beasties concerned. Hope you like it.

HI

Well there is some news on this, I am very much the layman, but I think there is something to report.  The newts have yet to show but, the frogs have avoided the main pond and only spawned in the seperate 'spawning pool'.  Now this was only dug in the winter, and last season the frogs spawned in the main pond.  The preditory fish were not present last year either, so this leads me to believe that the amphibians so far have spawned outside the main pond for either one or a combination of the two differneces.

Either they can sense the presence of preditory fish and have refused to spawn in the pond, or they simply prefer the small pool.  Now the small pool is equal depth to the shallow end of the pond so I dont think that depth is the attraction, so my hunch is the presence of the Perch has been detected and the frogs have made a choice.  It will be interesting to see what the newts do later on.  The frogs have been very active in teh pond, including courting, but, decided to lay in the pool.

Any theories????

Hi Martin

Your right on both counts - the shallow water is attractive to the frogs - i.e. the water is warmer. The presence of fish is probably also detected by the frogs - similar to crested newts which also detect the presence of sticklebacks in recent studies.

The newts may also decide to use the smaller pond more often than the larger pond - though I am not sure whether palmate newts have been shown to detect the presence of predatory fish though there is evidence (such as your possible observations) which may point to this.

JC

Hi

Well the newts have arrived,  havent found any spawn yet, but I have seen males and females in the main pond at night, not seen any courtship yet. 

All the frog spawn has successfully hatched, i have gazillions of taddies in the tiny pool.  I will have to set at least half free into the main pond, this should increase the chances for the rest and install the right balance of nature in the main pond.  As cruel as it seems, I also want the dragon fly larvae to grow and the newts to reproduce so some of those taddies will have to become 'colateral damage'.

I have fitted what is essentially a minature 'shark net' in the main pond, which sections of the shallow end.  This keeps the fish out and gives the newts a chance to lay at least without being eaten.  The entire pond bottom and sides are a rocks and boulders so once hatched any fry/tadpoles will have a place to hide away from most predators.

Its all going well, i just wish we had Cresties in the are (south somerset) they might have moved in to the little haven. The Perch will go soon, I may keep one which wont have much on an impact, I feel its the right balance.

M

Don't feel too bad about accepting some taddies will be fodder for other species. When I got my pond the best thing I am hoping for is grass snakes - I get them in the garden occasionally - and if a few froglets become the meal that attracts them, well so be it.

I do wonder sometimes about the presence of GCNs and wonder if it is sometimes a case of not knowing they are about. A neighbour and I were chattting last week, he does gardening, and he was telling me about removing a large amount of blanket weed from a customer's pond and in it were "hundreds" he said of huge newts (indicated about 9-10"). He knows the smaller species we have in our ponds locally. He said the pond owner had no idea they were in there. He placed the weed on the edge for them to wriggle back to the pond. Maybe there are places with GCNs that are not known as no surveying is done. They are not supposed to be in my area but obviously are as another one turned up in a garden pond the other year about a mile away from the large group.

Wow, hundreds! of GCN.  Lucky fella, I just hope that blanket weed wasnt full of spawn.

I have thought about removing all fish from my pond, afetr all there is no shortage of fish in the UK, of the species I hav anyway.  Maybe that will attract cresties if there are any here, i am right on the edge of farmland and meadow so there must be a chance.

Well, as you can see, they returned, a very fat female, one of several I saw tonight, and a few males too including the very pale (albino?) male in the other pic.

Well there were at least 6 pairs courting this evening so there may be hope.  I didnt realise the newts ate the eggs, newts arent nice at all are they, they eat the taddies too.

I am going to seperate about a dozen and hatch them out of the pond, just to ensure a few make it to an inch, then they can go back. Noticed what looked like a few very young dragon fly nymphs around, i am lucky enough to get the huge dragonflies in my garden, big blue ones (emperors I think?) so i want to keep them too but there will be an almighty struggle in the little eco system that is my garden this year.

Hi Martin,

I think Suzi's referring to the dragonflies as being 'not such good guys' rather than the newts ;)

Martin,

I don't have a clue how many tadpoles a dragonfly consumes before it leaves the pond, but it's probably fair to say quite alot!. They are certainly voracious predators. Personally I would leave the dragonfly larvae there and let the food chain take it's course. It's reasons like this why amphibians generally lay so many eggs I think.