Q: Fish/Killifish Identification

[DailyLunatic]

First, a little background. I have a new tilapia pond. Dug April 10, 2023. Released 8 Pladdies from my Pot Pond to keep mosquitos down on May 15, 2023. Multiple failed attempts to get duckweed started. Stocked with Tilapia fingerlings July 14, 2023.

Over the last few days I have noticed several small guppy/minnow sized fish nibbling at the Tilapia feed. These are a fraction of the size of the Tilapia fingerlings, so I know they could not be stunted Tilapia, and my Tilapia would not be spawning until February or March of 2024 at the earliest. I introduced some smaller guppy sized pellets for them as well, which the larger took well enough, though the smaller still had to nibble around it.

There are dozens of them and range in size from 1/4" to 1-1/2". They are hard to make out as the water is milky (it is a non-ornamental pond). At first I had assumed they were decedents of the Pladdies I had released, but the coloring was wrong. Even in the milky water they were too pale and not a bright orange. If they were not the Pladdies, then I could not figure out how they got into the pond.

Today I got a better look and went to the inter-webs to see what kind of fish these might be. I am in Surin Provence, Central Thailand. It 'appears' to be this guy, or a close relative. They have the black line along the dorsal ridge, but I do not remember seeing a white dot on the head. They are distributed among ornamental fish keepers. If it is this guy, he will be going in my home aquarium when I am ready.
A Blue Panchax Killifish

Aplocheilus panchax summary page

www.fishbase.se

On to my Question:
I've been trying to figure out how this guy got into so new a pond. There has been no flooding since the pond was dug, (although the area is prone to flooding).
I know that some Killifish are Annuals, meaning they lay their eggs, and the eggs can survive, even require, months and longer periods of drought, hatching when water is available again. Where the ponds have been dug used to be a rice field, so that would fit. However, information I have been able to find indicates that the Blue Panchax is a Perennial, not an Annual.

The only things I can think of are:
-Eggs Hitchhiked on a bird or the like. If so, Would they have increased in population so quickly?
-Eggs Hitchhiked in one of the duckweed attempts? Most likely July 20, 2023 as it was the least inspected. A dip and dump from a neighbor's pond. Eggs perhaps, but I doubt fish were included. Again, it askes the question how they could increase in population so quickly.
-A variety of Killie that looks similar to Blue Panchax, but is Annual.
-Wife and locals insist they flop along the ground, in the rain, across the rice field, up a 3 foot berm, across a 10 foot flat of ground, and into my pond. They are here, why do you care?

Have no fear. I like the idea of having a mosquito fish in the pond. (-...zzzz...smack- believe me, I like the idea) I encourage their continued health, but if they are an annual fish, that is not likely. They would age and die, and the eggs would not dry as required.

I just can't figure out how so many got in there so quickly.

Just tossing this out for discussion.

Thank you for your attention,
-sterling

 

[Sgooosh]

First, a little background. I have a new tilapia pond. Dug April 10, 2023. Released 8 Pladdies from my Pot Pond to keep mosquitos down on May 15, 2023. Multiple failed attempts to get duckweed started. Stocked with Tilapia fingerlings July 14, 2023.

Over the last few days I have noticed several small guppy/minnow sized fish nibbling at the Tilapia feed. These are a fraction of the size of the Tilapia fingerlings, so I know they could not be stunted Tilapia, and my Tilapia would not be spawning until February or March of 2024 at the earliest. I introduced some smaller guppy sized pellets for them as well, which the larger took well enough, though the smaller still had to nibble around it.

There are dozens of them and range in size from 1/4" to 1-1/2". They are hard to make out as the water is milky (it is a non-ornamental pond). At first I had assumed they were decedents of the Pladdies I had released, but the coloring was wrong. Even in the milky water they were too pale and not a bright orange. If they were not the Pladdies, then I could not figure out how they got into the pond.

Today I got a better look and went to the inter-webs to see what kind of fish these might be. I am in Surin Provence, Central Thailand. It 'appears' to be this guy, or a close relative. They have the black line along the dorsal ridge, but I do not remember seeing a white dot on the head. They are distributed among ornamental fish keepers. If it is this guy, he will be going in my home aquarium when I am ready.
A Blue Panchax Killifish

Aplocheilus panchax summary page

www.fishbase.se

View attachment 324299

On to my Question:
I've been trying to figure out how this guy got into so new a pond. There has been no flooding since the pond was dug, (although the area is prone to flooding).
I know that some Killifish are Annuals, meaning they lay their eggs, and the eggs can survive, even require, months and longer periods of drought, hatching when water is available again. Where the ponds have been dug used to be a rice field, so that would fit. However, information I have been able to find indicates that the Blue Panchax is a Perennial, not an Annual.

The only things I can think of are:
-Eggs Hitchhiked on a bird or the like. If so, Would they have increased in population so quickly?
-Eggs Hitchhiked in one of the duckweed attempts? Most likely July 20, 2023 as it was the least inspected. A dip and dump from a neighbor's pond. Eggs perhaps, but I doubt fish were included. Again, it askes the question how they could increase in population so quickly.
-A variety of Killie that looks similar to Blue Panchax, but is Annual.
-Wife and locals insist they flop along the ground, in the rain, across the rice field, up a 3 foot berm, across a 10 foot flat of ground, and into my pond. They are here, why do you care?

Have no fear. I like the idea of having a mosquito fish in the pond. (-...zzzz...smack- believe me, I like the idea) I encourage their continued health, but if they are an annual fish, that is not likely. They would age and die, and the eggs would not dry as required.

I just can't figure out how so many got in there so quickly.

Just tossing this out for discussion.

Thank you for your attention,
-sterling

I think some fish got caught in the duckweed, and ended up breeding. killifish breed very readily

 

[DailyLunatic]

I think some fish got caught in the duckweed, and ended up breeding. killifish breed very readily

Seems like a lot in just 2 weeks.

 

[Colin_T]

eggs in plants.
they don't hop along the ground and die quickly when out of water. under good conditions they can breed when 1-2 months old.

 

[ClownLurch]

Neighbours wanted a bit of room in their tank for something else?

 

[TNG]

First, a little background. I have a new tilapia pond. Dug April 10, 2023. Released 8 Pladdies from my Pot Pond to keep mosquitos down on May 15, 2023. Multiple failed attempts to get duckweed started. Stocked with Tilapia fingerlings July 14, 2023.

Over the last few days I have noticed several small guppy/minnow sized fish nibbling at the Tilapia feed. These are a fraction of the size of the Tilapia fingerlings, so I know they could not be stunted Tilapia, and my Tilapia would not be spawning until February or March of 2024 at the earliest. I introduced some smaller guppy sized pellets for them as well, which the larger took well enough, though the smaller still had to nibble around it.

There are dozens of them and range in size from 1/4" to 1-1/2". They are hard to make out as the water is milky (it is a non-ornamental pond). At first I had assumed they were decedents of the Pladdies I had released, but the coloring was wrong. Even in the milky water they were too pale and not a bright orange. If they were not the Pladdies, then I could not figure out how they got into the pond.

Today I got a better look and went to the inter-webs to see what kind of fish these might be. I am in Surin Provence, Central Thailand. It 'appears' to be this guy, or a close relative. They have the black line along the dorsal ridge, but I do not remember seeing a white dot on the head. They are distributed among ornamental fish keepers. If it is this guy, he will be going in my home aquarium when I am ready.
A Blue Panchax Killifish

Aplocheilus panchax summary page

www.fishbase.se

View attachment 324299

On to my Question:
I've been trying to figure out how this guy got into so new a pond. There has been no flooding since the pond was dug, (although the area is prone to flooding).
I know that some Killifish are Annuals, meaning they lay their eggs, and the eggs can survive, even require, months and longer periods of drought, hatching when water is available again. Where the ponds have been dug used to be a rice field, so that would fit. However, information I have been able to find indicates that the Blue Panchax is a Perennial, not an Annual.

The only things I can think of are:
-Eggs Hitchhiked on a bird or the like. If so, Would they have increased in population so quickly?
-Eggs Hitchhiked in one of the duckweed attempts? Most likely July 20, 2023 as it was the least inspected. A dip and dump from a neighbor's pond. Eggs perhaps, but I doubt fish were included. Again, it askes the question how they could increase in population so quickly.
-A variety of Killie that looks similar to Blue Panchax, but is Annual.
-Wife and locals insist they flop along the ground, in the rain, across the rice field, up a 3 foot berm, across a 10 foot flat of ground, and into my pond. They are here, why do you care?

Have no fear. I like the idea of having a mosquito fish in the pond. (-...zzzz...smack- believe me, I like the idea) I encourage their continued health, but if they are an annual fish, that is not likely. They would age and die, and the eggs would not dry as required.

I just can't figure out how so many got in there so quickly.

Just tossing this out for discussion.

Thank you for your attention,
-sterling

The locals are correct. In that part of the world: you build a pond and the fish will come.

By the end of the rainy season, around late November, farmers will dig holes around 2’ deep near the water edge of their paddy fields to catch fish. By morning, it’s full of fish, snakeheads, catfish, etc. the fish climb out of the water and crawl into the trap. I’m told the fish follow the smell of freshly dug earth, though I have no way of proving that.

 

[DailyLunatic]

Neighbours wanted a bit of room in their tank for something else?

No. She has Ponds.
The neighbor raises Tilapia and Frogs for sale. She uses Duckweed, Water Hyacinth, and Water Lettuce to improve her water quality. When her pond gets over 90% covered she will harvest and usually mulches her garden. She heard I needed some and gave me a bushel basket of each. (Note: Water Hyacinth and Water Lettuce are regulated/illegal in many US States. Please be aware of, and follow your local regulations.)

In 17 days, my Water Hyacinth has increased somewhat in volume (15%?), and is looking great. The Water Lettuce has tripled in volume, though it is a bit sickly looking and yellowing from what she gave me. And the Duckweed has disappeared entirely. I have never been able to keep Duckweed alive to save my life, even in my aquariums.

This is happening in both ponds, one with fish, the other without (well, without those possibly introduced along with the Duckweed, that is.), so I don't feel predation on the Duckweed is the issue. Most likely some water parameter or nutrient/mineral deficiency that Duckweed does not like. Originally, I had thought it to be a full-sun issue, but as her ponds are also full-sun, I have ruled that out.

Next step in the fish identification will be capture and closer examination. I already have a trap and netting on the way because of another invader. Estimated arrival in approx. 7 more days.

-sterling

 

[Colin_T]

the fish in the picture is a blue panchax killifish

 

[DailyLunatic]

the fish in the picture is a blue panchax killifish

Yes it is, because I pulled that example off the internet.

When I capture some I will post pictures at that time. Traps incoming.

-sterling

 

[Colin_T]

You could go spotlighting at night. That's how some people catch rainbowfish. They wander around with a spotlight and long handled net and scoop the sleeping fish up. The spotlight is also useful for spotting chocodiles in the area.

 

[DailyLunatic]

Sorry. I've been away from the forums for a while. Life got in the way, what can I say.

Thought I'd catch-up the group on what I found on these unknowns.

First, I did manage to get the minnow trap and did trap a few for closer examination. I trapped daily for 1 week and found the following:

1] 1 Blue Panchax Killifish
2] A few Juvenile Tilapia. In a pond of Juveniles, this is to be expected.
3] About a kagillion Tilapia Fingerlings. These are smaller than the fingerlings I had released to the pond just 31 days prior. (Negative growth rate?)

In another post I gave the log of events that most likely lead to me having Tilapia Fingerlings in a pond where the fish I released into it are not yet of breading age. Wife had (trying to be helpful) released 7 juveniles into the pond a few weeks before I released the fingerlings to the pond. (long story, but cut to the chase, I've lost control of my life)
6 of the 7 went belly up the next morning. The remaining survived for a few days before it too was found.

My mistake was confusing Harvest Age with Breeding Age. I had assumed Harvest Age was Adult. My bad. Apparently they begin laying at around 12 weeks, and to my eyes are still juveniles, while Harvest Age is around 6 - 8 months.

Being Mouth Brooders, any one of, or multiple, of these 7 could have had fry with her when released into the pond. I honestly never considered the possibility that Tilapia smaller than my hand could have been of breeding age. Live and learn.

The initial release of fingerlings, now juveniles, are 11 weeks old now, and just smaller than my hand. Coincidentally, I'm seeing the exact same small fish on the surface of the water.

Mystery solved

.

 

[GaryE]

That isn't an annual, or a fish that breeds quickly. They must have come in adult with plants, tangled into their hiding places. You would need several months to get them to breeding size, if I recall, at least 3-4. Aplocheilus panchax has been kept in aquariums for ages, not because of its colours, which as you can see are dull, but because it's hardy. They breed like mice once you get them going.

There aren't many Asian killies, but the family is ancient - they are found in Africa, Europe, Asia, both Americas (even just down the road from me in Canada, where a local University is studying cold tolerant Fundulus heteroclitus) - everywhere unfrozen except Australia. By now, if you slide a net under the floating vegetation and pull it up quickly, you'll probably catch dozens. They are voracious mosquito eaters (look at the upturned mouth for surface strikes).

 

[Colin_T]

Tilapia can breed when 2-3 inches long. If there are any fish that size, they could be breeding.