# How do fish get into man made lakes? **URL:** \ **Category:** Factual Questions\ **Created:** [May 11, 2004, 10:07pm UTC](https://boards.straightdope.com/t/how-do-fish-get-into-man-made-lakes/244696 "2004-05-11T22:07:11Z")\ **Posts on this page:** 12\ **Page:** 2
**Author:** ![kniz](https://avatars.discourse-cdn.com/v4/letter/k/c37758/32.png) [@kniz](https://boards.straightdope.com/u/kniz)\ **Post date:** [May 13, 2004, 2:41am UTC](https://boards.straightdope.com/t/how-do-fish-get-into-man-made-lakes/244696/21 "2004-05-13T02:41:48Z")
šŸ˜‰ [sup]**Just to cover all bases there have been reports of it raining fish (&frogs).**[/sup] ---
**Author:** ![Revrezner](https://avatars.discourse-cdn.com/v4/letter/r/3da27b/32.png) [@Revrezner](https://boards.straightdope.com/u/Revrezner)\ **Post date:** [May 16, 2017, 7:48pm UTC](https://boards.straightdope.com/t/how-do-fish-get-into-man-made-lakes/244696/22 "2017-05-16T19:48:55Z")
In FL where I live the game fish and wildlife department adds fish to man-made bodyā€™s of water. This itā€™s to combat mosquitoes. Canals, lakes and man made bodyā€™s off water are common here. They build long rows of channels of water with rows of soil. The fish eat the insect eggs and naturally controls the insects. ---
**Author:** ![Omar\_Little](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/omar_little/32/269_2.png) [@Omar\_Little](https://boards.straightdope.com/u/Omar_Little)\ **Post date:** [May 16, 2017, 7:57pm UTC](https://boards.straightdope.com/t/how-do-fish-get-into-man-made-lakes/244696/23 "2017-05-16T19:57:49Z")
The Northern Snakehead, a predatory Asian fish that has expanded into the Potomac, the Hudson Bay, Arkansas and other locations in the US. Per the US Geological Survey conclusions: > [@](#): > > Prior to being added to the list of injurious wildlife under the Lacey Act in October 2002, which banned import and interstate transport without a permit from the U.S. Fish and Wildlife Service, snakeheads were sold in pet stores and in live food fish markets and some restaurants in several major U.S. cities, including Boston, New York, and St. Louis. Live specimens have been confiscated by authorities in Alabama, California, Florida, Texas, Virginia, and Washington where possession of live snakeheads is illegal. > > Some snakeheads living in natural waters of the U.S. may have been released by aquarium hobbyists or those hoping to establish a local food resource. Also, some cultures practice ā€œprayer animal releaseā€, a faith-based activity in which individuals purchase, then release, an animal (fish, amphibian, reptile, or bird) to earn merits with a deity. [https://www2.usgs.gov/faq/categories/9787/3000%20](https://www2.usgs.gov/faq/categories/9787/3000%20) Blame the gods! ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [May 17, 2017, 7:41am UTC](https://boards.straightdope.com/t/how-do-fish-get-into-man-made-lakes/244696/24 "2017-05-17T07:41:07Z")
> [@mmmiiikkkeee](#): > > No way could that happen. The eggs would be long dead and dissolved after passing through a bird. I wouldnā€™t rule it out so quickly - in general, birds have a pretty fast digestive transit - which is why so many plants use them successfully to distribute seeds. Now, fish eggs are not seeds of course, but there are examples of fish eggs that are quite tolerant of other difficult conditions such as dehydration. Like the colonisation of islands by animals surviving on floating debris - It only has to succeed once in a million cases, against the odds, to still be a reality. ---
**Author:** ![watchwolf49](https://avatars.discourse-cdn.com/v4/letter/w/e9c0ed/32.png) [@watchwolf49](https://boards.straightdope.com/u/watchwolf49)\ **Post date:** [May 17, 2017, 2:12pm UTC](https://boards.straightdope.com/t/how-do-fish-get-into-man-made-lakes/244696/25 "2017-05-17T14:12:25Z")
> [@vetbridge](#): > > > [@](#): > > > > There are also fishless natural lakes. > > I can attest to that fact. I have spent many hours fishing these types of lakes. > > šŸ˜‰ Indeed ā€¦ fish are complete extinct in the State of Oregon ā€¦ ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [May 17, 2017, 2:18pm UTC](https://boards.straightdope.com/t/how-do-fish-get-into-man-made-lakes/244696/26 "2017-05-17T14:18:31Z")
> [@Mangetout](#): > > I wouldnā€™t rule it out so quickly Mayhaps heā€™s changed his mind in the 13 years since he posted that. šŸ˜ƒ ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [May 17, 2017, 2:32pm UTC](https://boards.straightdope.com/t/how-do-fish-get-into-man-made-lakes/244696/27 "2017-05-17T14:32:11Z")
OK. I wouldnā€™t rule it out so _slowly_. Dammit zombie threads. ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [May 17, 2017, 2:33pm UTC](https://boards.straightdope.com/t/how-do-fish-get-into-man-made-lakes/244696/28 "2017-05-17T14:33:03Z")
I once had this large plastic container that I used to mix up soil for carnivorous plants, and over time it filled with rain water. I glanced in it once and noticed it moving around and somehow it had been colonized by [ostrocods](https://en.wikipedia.org/wiki/Ostracod). Donā€™t know if the eggs were in one or the soil components or were brought in by birds. ---
**Author:** ![mmmiiikkkeee](https://avatars.discourse-cdn.com/v4/letter/m/edb3f5/32.png) [@mmmiiikkkeee](https://boards.straightdope.com/u/mmmiiikkkeee)\ **Post date:** [May 17, 2017, 4:41pm UTC](https://boards.straightdope.com/t/how-do-fish-get-into-man-made-lakes/244696/29 "2017-05-17T16:41:23Z")
> [@Really\_Not\_All\_That\_Bright](#): > > Mayhaps heā€™s changed his mind in the 13 years since he posted that. šŸ˜ƒ Nope, still havenā€™t changed my mind. You have to keep in mind that seeds are specifically adapted to pass through a given animals digestive system and the conditions encountered there; so they may have physical characteristics making them difficult to mechanically crush and thick ā€œskinsā€ resistant to acid and digestive enzymes for example. While there are some species of fish whose eggs are hardier than others, they are typically adapted to be resistant to environmental conditions encountered where they evolved. Those eggs may be resistant to desiccation, higher salinity, or limited amounts of freezing or low oxygen environments. Iā€™m not aware of any fish species whose eggs are adapted to resist the mechanical grinding of a birds crop and the chemical digestive process theyā€™d be exposed to after being eaten. Many species of animals seek out fish eggs as a food source because they are so nutritious and digestible. Resistance or toughness in fish eggs is usually with respect to a few parameters, not all of them. ---
**Author:** ![Shagnasty](https://avatars.discourse-cdn.com/v4/letter/s/9dc877/32.png) [@Shagnasty](https://boards.straightdope.com/u/Shagnasty)\ **Post date:** [May 17, 2017, 5:19pm UTC](https://boards.straightdope.com/t/how-do-fish-get-into-man-made-lakes/244696/30 "2017-05-17T17:19:01Z")
The idea that I have heard isnā€™t that it comes from birds swallowing them and pooping them out but simply because the eggs can stick to their feet, bodies or beak and then get redeposited in another place. I stand by my original statement as well. In the Deep South, you can dig something like a brand new farm pond in a pasture that isnā€™t connected to anything else and you WILL have fish in it within a few months to a year. Many of them arenā€™t the types of fish that people stock either. They range from small minnows to sunfish. Bass and catfish (including undesirable mudcats) will show up a little later along with frogs and snakes. Something is putting them there and birds are one of the only explanations that makes sense. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [May 18, 2017, 7:03am UTC](https://boards.straightdope.com/t/how-do-fish-get-into-man-made-lakes/244696/31 "2017-05-18T07:03:06Z")
> [@mmmiiikkkeee](#): > > Nope, still havenā€™t changed my mind. You have to keep in mind that seeds are specifically adapted to pass through a given animals digestive system and the conditions encountered there; so they may have physical characteristics making them difficult to mechanically crush and thick ā€œskinsā€ resistant to acid and digestive enzymes for example. > > While there are some species of fish whose eggs are hardier than others, they are typically adapted to be resistant to environmental conditions encountered where they evolved. Those eggs may be resistant to desiccation, higher salinity, or limited amounts of freezing or low oxygen environments. Iā€™m not aware of any fish species whose eggs are adapted to resist the mechanical grinding of a birds crop and the chemical digestive process theyā€™d be exposed to after being eaten. > > Many species of animals seek out fish eggs as a food source because they are so nutritious and digestible. Resistance or toughness in fish eggs is usually with respect to a few parameters, not all of them. Iā€™m not saying that I think itā€™s likely, or anywhere near the most common scenario - but I do think itā€™s probably just about possible under the freakishly right combination of circumstances (which could, I suppose, include such things as health factors in the bird, preventing its digestion from working optimally). Given enough variables and enough rolls of the dice, even the most unlikely outcomes can occasionally pop up. Thereā€™s a lot of quite sensible discussion on the topic [here](https://www.researchgate.net/post/Is_there_scientific_proof_that_water_fowl_can_transport_fish_eggs_from_one_water_body_to_an_other), including a reference to a published paper which claims to have observed viable fish eggs collected from bird feces ---
**Author:** ![Sauron](https://avatars.discourse-cdn.com/v4/letter/s/ce7236/32.png) [@Sauron](https://boards.straightdope.com/u/Sauron)\ **Post date:** [May 18, 2017, 6:43pm UTC](https://boards.straightdope.com/t/how-do-fish-get-into-man-made-lakes/244696/32 "2017-05-18T18:43:08Z")
**How do fish get into man-made lakes?** ā€œPractice, man, practice.ā€ [Previous page](https://boards.straightdope.com/t/how-do-fish-get-into-man-made-lakes/244696.md?page=1)