FROG KILLS KOI IN UK POND

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Ian Taylor

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Mar 7, 1998, 3:00:00 AM3/7/98
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My friend has a largish (approx. 800 gallon pond). In it there are
goldfish and koi. Lately he has found a couple of the bigger koi dead for
no apparent reason. Today he was in the garden when he saw a fish rolling
around in the pond. He netted it (a koi about 8 inches long) and on its
back was a large frog. The frog had to be prised off the fish, I assume it
was attempting to mate with the frog! This is not a joke, it is quite true.
Has anyone else seen this phenomenon and has it killed their fish?

Also the dead fish were at the bottom of the pond. What makes dead ones
float or sink? Is it gas like in most corpses, in this case in the swim
bladder?

Thanks

Ian

>--0-0-->

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Mar 7, 1998, 3:00:00 AM3/7/98
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Is your friend sure the frogs actually killed the fish? I have loads of
frogs in my pond and they don't kill fish by riding on them or trying to
mate with them. There may be another problem in this pond. The fish are
strong and slimy and not an easy thing for a frog to hold on too. Also
frogs let go of things that don't "act" like female frogs. If a male grabs
a male by accident or whatever = he lets go when he realizes there is no
ready female there in his grasp.
--
Carol.....
**Fundamentalism - the horrible fear that someone, somewhere is having
fun**
~~~*~~~*~~~*~~~*~~~*~~~*~~~*~~~*~~~*~~~*~~~*~~~*~~~*


Ian Taylor <i...@threedee.force9.co.uk> wrote in article

Graham Fell

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Mar 7, 1998, 3:00:00 AM3/7/98
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As a UK ponder with gf and many frogs, I've never had this problem - but
got no koi. In fact I think the gf eat the tadpoles but still.
Incidentally the spawn is so early this year due to a v. mild UK Feb. that
any major frosts will kill some of the top spawn. We're hoping for an
average March

Graham (Cumbria)

Kellie

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Mar 7, 1998, 3:00:00 AM3/7/98
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> The frog had to be prised off the fish, I assume it
> was attempting to mate with the frog! This is not a joke, it is quite true.
> Has anyone else seen this phenomenon and has it killed their fish?

Ian- I was told about this when I first set up my ponds, but you are the first
other person to mention it! A guy who gave a pond seminar here in Dallas said
that toads and frogs will sometimes latch onto a fish and restrict its
breathing or whatever and kill it! Bizarre!--
Kellie
Always be kind to animals, Morning, noon and night:
For animals have feelings too, And furthermore, they bite. - John Gardner

Mark A Jensen

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Mar 7, 1998, 3:00:00 AM3/7/98
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I saw a television show on Cane Toads in Australia. It said that they
would mate with anything that would move, including a person's foot! When
frogs mate, the male grasps onto the female very strongly (i believe the
term is amplexus). This would surely kill a fish if a horny toad (bad
pun) were to do this. I wouldn't underestimate the power of sex.

Mark

Jan Jordan

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Mar 8, 1998, 3:00:00 AM3/8/98
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>On 7 Mar 1998 19:12:35 GMT, "Ian Taylor" <i...@threedee.force9.co.uk> wrote:

>My friend has a largish (approx. 800 gallon pond). In it there are
>goldfish and koi. Lately he has found a couple of the bigger koi dead for
>no apparent reason. Today he was in the garden when he saw a fish rolling
>around in the pond. He netted it (a koi about 8 inches long) and on its

>back was a large frog. The frog had to be prised off the fish, I assume it


>was attempting to mate with the frog! This is not a joke, it is quite true.
>Has anyone else seen this phenomenon and has it killed their fish?

I've heard of the female frog sometimes getting drown by the male
while mating, but this sounds like one screwed up male frog. I hope
your friend removed it from the area (frog legs anyone?) after he
removed it from the fish.

>Also the dead fish were at the bottom of the pond. What makes dead ones
>float or sink? Is it gas like in most corpses, in this case in the swim
>bladder?

I imagine that's it. In this case they sank cause they've had the gas
squeeze right out of them?

~Keep 'em Wet!~
jan/3-Cities WA
Zone 7
Remove Z to e-mail


Pete Bradbury

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Mar 8, 1998, 3:00:00 AM3/8/98
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In article <mjensen-0703...@130.191.9.184>, Mark A Jensen

I've heard of this before from my neighbour whbaose father keeps Koi,
but so far - touch wood - its not happened to ba fish. So far as
fatalities are concerned, this year none - probably due to it being such
a mild winter in the UK, most years with a frozen pond, appprox 2-4
fatalities.

I suppose you've also got to bear in mind that in the 'spring' fish are
likely to be pretty weak, and a strong toad or frog could be just too
much for an enfeebled fish.

Regards,

Pete

--
Pete Bradbury
================================================
ARM powered !!!!!!!!!!! RiscPC 700 - 42 meg RAM
================================================


Madhusudan Natarajan

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Mar 10, 1998, 3:00:00 AM3/10/98
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In article <mjensen-0703...@130.191.9.184>, mje...@rohan.sdsu.edu (Mark A Jensen) wrote:

>
>I saw a television show on Cane Toads in Australia. It said that they
>would mate with anything that would move, including a person's foot! When
>frogs mate, the male grasps onto the female very strongly (i believe the
>term is amplexus). This would surely kill a fish if a horny toad (bad
>pun) were to do this. I wouldn't underestimate the power of sex.
>

>Mark

This is a little fallacious. The article you saw was very loosely interpreting
things. Frogs (henceforth frog = frog/toad) can try and mate with anything -
they have no "sense" that way, .. but <hidden caveats> the pattern followed is
as follows.

The female swims around (or moves around depending on where it is). The male
frog follows close behind half piggy-back riding so that it can fertilize all
the eggs the female is releasing. To do this, male frogs usually end up
clutching the female front limbs. The usual pattern is to grasp the female
close to the "toes" where there actually exists a sort of fleshy glob which
helps in grabbing a hold.

Its not as if the frog can stick to anything in its frenzy to mate. It needs
to grasp the object rather tightly. A human foot has the necessary digits and
spaces in between to permit such a hold. A biggish smooth slippery koi with a
slime coat is in no danger because theres no way a frog can stay anchored on
it (no holds). A teeny koi and a biggish frog.... maybe.. and even there there
is no danger of suffocation because the gills arent clamped down.

Id be more worried about the following
Big koi, small toad.. toad = dinner, and some toads are poisonous
Small fry koi, biggish frog.. koi = dinner.


Madhusudan Natarajan
Northwestern University, Evanston, IL. USA
m-nat...@nwu.edu

Walter Knapp

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Mar 10, 1998, 3:00:00 AM3/10/98
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Malcolm Burnage wrote:
>
> Unfortunatly frogs can and do kill fish:
> My stepson has just very nearly lost his prize Sturgeon because a frog
> straped itself across it's head and had a leg in its gill, the fish is
> now in a paddling pool in the conservatory while it recovers. I have had
> a pond for more years than i can remember and have had frogs etc in my
> ponds with no problems but it shows you that it can happen.

I wonder if this is the correct interpretation, or did the Sturgeon grab
the frog and the frog grabbed back. Or the Sturgeon just sucked in a leg
when the frog was hiding in bottom debris. Frogs will grab like that
sometimes when snakes grab them. Once in a while it helps.

We tend to think in favor of whichever we like the most, but it may not
be so. Also, I believe your details, but have no idea what scenario is
the real one.

Nature has some twists and turns. Including death.

Walt
wwk...@mindspring.com

Malcolm Burnage

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Mar 11, 1998, 3:00:00 AM3/11/98
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Unfortunatly frogs can and do kill fish:
My stepson has just very nearly lost his prize Sturgeon because a frog
straped itself across it's head and had a leg in its gill, the fish is
now in a paddling pool in the conservatory while it recovers. I have had
a pond for more years than i can remember and have had frogs etc in my
ponds with no problems but it shows you that it can happen.
By the way he would like to know if there are any other
Sturgeon/Stertlet keepers out there.

In article <6e2ck6$208...@acns.nwu.edu>, Madhusudan Natarajan <m-
nata...@nwu.edu> writes

-- remove delete. for email return
Malcolm Burnage

julien Dussaix

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Mar 18, 1998, 3:00:00 AM3/18/98
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i try to find goldfish adress on the wed please help-me, and give me
some.

julien Dussaix

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Mar 18, 1998, 3:00:00 AM3/18/98
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Madhusudan Natarajan

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Mar 18, 1998, 3:00:00 AM3/18/98
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In article <350F98...@club-internet.fr>, sha...@club-internet.fr wrote:

$$i try to find goldfish adress on the wed please help-me, and give me
$$some.

. a few..
http://www.geocities.com/Tokyo/4468/
http://www.aquafind.com/
http://members.aol.com/Lazulifawn/index.html
http://www.koivet.com/goldfish/
http://www.nucleus.com/~mchow/fishcentral/coldwater.htm
http://www.cdepot.net/2birdsgoldfishfarm/
http://www.aqualink.com/fresh/species.html .. and scroll down to goldfish.
. and I have tons more. Im bored with typing them up here..

Seriously, there are about a million pages out there on the web. I suggest you
learn to use search engines more efficiently.

GTong

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Mar 18, 1998, 3:00:00 AM3/18/98
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>> i try to find goldfish adress on the wed please help-me, and give me

>> some.

Try this: <http://www.geocities.com/Tokyo/4468/>.

--
"Every infinity is composed of only two halves."

(Remove ".out" for my email address.)

Marcy Greeley

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Mar 21, 1998, 3:00:00 AM3/21/98
to sha...@club-internet.fr

julien Dussaix wrote:

>
> julien Dussaix wrote:
> >
> > i try to find goldfish adress on the wed please help-me, and give me
> > some.


You might want to check out
the Goldfish Home Page at:

http://www.mindspring.com/~fishvet/gfindex.htm

...or do a search on Yahoo! with the word "goldfish"...
good luck,
Marcy
http://www.tekkers.com/pond.html

julien dussaix

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Mar 22, 1998, 3:00:00 AM3/22/98
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please give me some pictures of goldfish and web sites on, thanks.

suki...@gmail.com

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Apr 10, 2017, 6:43:36 PM4/10/17
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I found this blog while trying to find anything I could about frogs killing koi fish. We have a very large natural pond with 12 medium to large koi. Last spring for the first time we started to see tiny black fish in the pond, needless to say they were baby koi. We had a few hundred, many were eaten and many others just didn't make it. This spring, we were surprised to find that about 60 of the had made it through the winter. A few days ago, we began to hear loud noises from around the pond, it sounded like a bunch of turkeys. Well it turned out to be hundreds of small black frogs. I didn't mind until I saw one go after one of the baby koi and get on its back. I scared it off, but the koi was already dead. I began to watch them and they were hanging around where the koi tend to congregate, they float there as if they're dead and when a small koi swims by, they aggressively swim after it and and get on its back killing it in seconds. They were wiping out my entire small koi population, I even wondered if they possibly had some type of poison in them. So glad to hear that this is not unheard of!

thompson...@gmail.com

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Mar 5, 2018, 1:31:10 PM3/5/18
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On Saturday, 7 March 1998 08:00:00 UTC, Ian Taylor wrote:
> My friend has a largish (approx. 800 gallon pond). In it there are
> goldfish and koi. Lately he has found a couple of the bigger koi dead for
> no apparent reason. Today he was in the garden when he saw a fish rolling
> around in the pond. He netted it (a koi about 8 inches long) and on its
> back was a large frog. The frog had to be prised off the fish, I assume it
> was attempting to mate with the frog! This is not a joke, it is quite true.
> Has anyone else seen this phenomenon and has it killed their fish?
>
> Also the dead fish were at the bottom of the pond. What makes dead ones
> float or sink? Is it gas like in most corpses, in this case in the swim
> bladder?
>
> Thanks
>
> Ian

i to have just had to seperate a frog grasping hold of one of my koi it was on its back and holding on very tight had a problem getting it off my koi died iv had frogs in my pond with koi for 6 years no problem that i know of till today

t44...@gmail.com

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Mar 24, 2018, 1:22:28 PM3/24/18
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I have just witnessed this myself , I have just netted my koi at bottom of pond with a frog on top of it-the frog had wedged its front feet into the fish gills killing the fish. It is mating season at the moment - so this is possible. I was a bit quick removing the frog from the koi to see if the fish was alive ... had I thought I could have taken a pic as I was pretty shocked as not witnessed anything like this before !

ianjam...@gmail.com

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May 7, 2018, 11:25:00 AM5/7/18
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Yes this has happened in my pond last winter noticed a fish at the bottom I thought was dead when I put it in the net and brought it to the surface notice a frog wrapped tightly around it I removed the frog and threw it over the garden fence the fish swam off but within 2 days it died.😬

natash...@gmail.com

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Feb 17, 2019, 3:43:36 AM2/17/19
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I have this happening to me right now, I don't have koi fish I have shubunkins. My poor little fish! It's gripped so tight around him that I can't take him off!

thebigyello...@gmail.com

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Mar 21, 2019, 4:49:04 PM3/21/19
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I’ve just had this happen too! But the frog wasn’t gripping the gills it had actually lodged its legs into the koi’s eyes!! Yes it’s eye sockets! How in gods name it had done it I don’t know but I literally had to prise this frog off my koi and pull its front legs out of the koi’s eye sockets! It’s dark right now so I can’t check my fish over easily but fingers crossed it’s alright? It swam away but there must be damage? I fk hope it survives. I’ve never seen or heard of the before! I’m guessing the only reason the fish isn’t dead, it that the frog didn’t attach to the gills and suffocate the koi. Maybe that means she can survive albeit properly blinded :(

c.ga...@sky.com

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Mar 27, 2019, 10:36:10 AM3/27/19
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Had the same issue here in suny Kent. Toad attached to the koi’s head, both front arms in the koi’s eyes but the toad was facing towards the tail - so the koi was able to breath but it looked like something from the film aliens. Doubtful it will have any sight left now but the toad - once removed - learnt how to fly into the neighbours garden.... apparently it only happens if there is no female toad in the pond...

Then an hour later noticed my black sturgeon was belly up on the bottom of the pond - scooped it out to find it too had a toad on its head. With Orange eyes and it had a claw or toe nail on each front hand (probably to grip the female) now the sturgeon is in a holding pool along with all my other fish. Had scrape marks all down it’s head where the toad had been trying to latch on. This was a big fish some 20” long yet it may not live the day thanks to a fk toad.

Anyone know of an “Anne summers” or “love honey” site for toads/frogs so I can get something else to distract the Randy so-and-so’s........

iainri...@gmail.com

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Apr 22, 2019, 11:11:41 AM4/22/19
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Hello ian i have two koi carp abd a frog was ob one the carps head yesterday gotvthecfrg of and today the frogcwas on thecsam koi carp again will my fish bebokay paula abd iain

hughesmi...@gmail.com

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Jun 1, 2019, 2:55:13 AM6/1/19
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We have had the exact same experience. The frogs killed all our fish by clinging on to them. I tried to prise them apart with no joy. We now keep our pond purely as a wildlife pond with no fish, which is better for wildlife anyway.

gregs...@gmail.com

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Jul 26, 2019, 5:44:53 AM7/26/19
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I have the opposite problem, not that I like frogs. But one of my larger koi grabs the frogs by the leg and carries them around the pond until they die. Then just toys with the dead frog like a child with a teddy bear.
I've had koi for a good few years and never seen this before.
Anyone seen this behaviour?

appsj...@gmail.com

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Jul 4, 2020, 7:45:05 PM7/4/20
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Myself and at least 3 others witnessed frogs clamping round the gills of koi carp in a pond in Bournemouth. We watched for a good half hour trying to work out what was actually happening. I genuinely believe they were trying to smother the fish. Definitely happened though no matter what the reason

Neene Price

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Apr 8, 2021, 8:38:07 AM4/8/21
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This definitely happens. I have lost 4 koi and several large orfe to this phenomenon this Spring. They clamp the gills shut so suffocate the fish or just exhaust the fish by the additional weight the fish have to carry around or damage their eyes from they clamp on there. They only seem to clamp onto large fish from what I have seen. I remove them where I can but often this happens overnight and death has occurred by the time I check the pond in the morning.
I used to love frogs and toads but I have definitely gone off them now.........
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