9 replies to this topic

[californiaminnow]

Stopped by Petco today to get snake supplies and noticed some odd fish in their feeder tanks. Thought I'd grab them in case they are some neat native fish. After adding to a planted tank at home I believe they are young sunfish. I have two of them, both about an inch long. Any ideas about specific species?

 

https://ibb.co/RQdcsk3

https://ibb.co/PmBwxQq

Edited by californiaminnow, 13 April 2021 - 06:21 PM.

[El Todd]

Green sunfish?

[Michael Wolfe]

Look here on the forum under Identification Assistance - Feeder Tank Finds and Identification

 

but I think El Todd is right

 

[centrarchid]

Green Sunfish are a frequent contaminant in bait-minnow production ponds. They are easily stocked by herons and the GS is really good at swimming into some overflows during heavy rain events. Farms I visit appear to have greater problem with herons moving a few that promptly breed to contaminate harvest that then shows up in feeder fish tanks. The farmers do not like the GS.

[swampfish]

How do herons move fish from one pond to another? Do they drop live fish while flying, regurgitate live fish, or move eggs on their legs? I have never heard of this before. I googled it and got nothing.

 

Phil Nixon

[El Todd]

How do herons move fish from one pond to another? Do they drop live fish while flying, regurgitate live fish, or move eggs on their legs? I have never heard of this before. I googled it and got nothing.

 

Phil Nixon

There's been some new research in this area indicating that fish transportation to new bodies of water can happen via things such as duck feces. I don't have a link though.

[gerald]

https://www.sciencen...ooped-out-ducks

This experiment was with carp eggs fed to mallards.  I can see how this might happen with mallards and other birds that slurp stuff off the bottom (spoonbill, flamingo) but seems unlikely with a targeted sight-feeder like a heron.

[El Todd]

https://www.sciencen...ooped-out-ducks

This experiment was with carp eggs fed to mallards.  I can see how this might happen with mallards and other birds that slurp stuff off the bottom (spoonbill, flamingo) but seems unlikely with a targeted sight-feeder like a heron.

 

Yup - that's the study, thanks for providing the link.

 

From what I know, some fish species have internal egg fertilization; but I have no idea which fish species have internal fertilization - or if any natives breed that way. I guess it stands to reason that it's possible for a heron to eat a fertilized fish and thus transport a new species to a new body of water; however, I have never seen any studies exploring/testing this particular possibility.

[centrarchid]

The herons catch a fish, usually one that is on the upper size range of what they like to consume, then they drop while trying to handle it. That is only part of the transplanting part. The heron needs to drop the fish so it can get into another body of water. Well the heron sometimes fly with fish in beak either to another location on same body of water or a perch near another body of water close by. The fish can be dropped in flight or from new perch. If fish able to reach open water without too much damage, then you have a stocking event of one fish.

 

I have seen herons drop green sunfish several times, most because I was the reason they opted to fly with a fish in beak. When ponds close together or near a stream, then odds pretty good that a fish will eventually be transplanted from one body to the next over time. Farthest I have seen heron carry a fish before dropping was about 100 yards.\

 

 

Then there is the business of fish moving overland during heavy spring and summer rain events. Multiple fish move at a time with those and they are much more predictable.

[centrarchid]

I mess with fish eggs a lot. Greens sunfish eggs and how they are deposited do not have any characteristics I would associate with good transport by water fowl. No fish eggs with survive passage through an avian digestive tract, with possible exception of annual killifishes. Even that is a stretch.