If there’s a lake or pond that is stocked continually/was at one point should the fish be considered a casual or wild observation? I’m going to go fishing soon at a place like this and would like to know what the appropriate protocol would be for this.
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Excellent question. I guess in theory an individual fish that was hatchery raised and then released in a watershed shouldn’t be considered wild. The challenge would be knowing that a particular individual was first-generation from the hatchery, or was one or more generations descended from stocked individuals (in which case I would consider them wild, even if non-native), or is maybe native to that watershed (if native species are ever supplemented with stocking? – I hope not…).
I’ll be interested to hear other thoughts – I am no fish biologist. Thanks for posting @comores3 and welcome to the forums!
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I would consider them to be cultivated. It is a very difficult grey area situation, and you will find as many suggesting for cultivated as you will for wild. In fact, it would be an interesting experiment to put this as a blind survey, and see how people vote!
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this is a very grey area, and i have wondered about that when fishing, except i am bad at catching fish so it never comes up :) I believe fishery ecologists can tell if a fish was wild born, because they usually mark or otherwise there are indications on a stocked fish. But, I don’t know how to do that. if it’s a stockie i’d mark as captive even though it’s dumped in a waterway because it’s not a natural population… but it’s complicated because often the fish WOULD survive if there wasn’t fishing. Other times, not so much.
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I’d say it depends on the potential for the stocked fish species to reproduce at that location. There are certainly some fishing locations in my state (New Mexico) where reproduction of stocked rainbows is impossible due to seasonal changes in water quality/temperature. Other locations may be continually stocked but there might also be reproduction. If nothing else, documenting an observation of a hatchery-reared fish at a stocking location indicates where establishment may potentially occur.
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I would consider the first generation to be escapees. They are no longer captive, and ‘cultivated’ should refer specifically to plants.
I’ve had this discussion with some birders regarding domestic mallards, where they were clearly no longer captive but flagged as such.
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the words are somewhat deceptive, but if humans release an animal into the wild i believe that first generation should still be flagged as not wild until/unless there is reproduction occurring. Granted with animals you often’ just don’t know and if so, leaving it as wild is fine.
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Just playing devils advocate, one could also posit that the hatchery just annexed a watershed to their hatchery operation by releasing the fish there. Thus the gray areas in this thought exercise… 
Well, if the watershed is no longer a wild space, then they’re still captive. But if the watershed is connected to the network of tributaries, and the released fish can freely move up and down the creek/river/etc, then they should be considered escapees.
IMO of course. :)
Not so hypothetical. Here’s a good example.
https://www.inaturalist.org/observations/26227881
This is at a pond in Tulsa Oklahoma that appears to be stocked:
We stock a lot of fish in Manitoba. I haven’t fished for a long long time, but once a fish is released (assuming it is indigenous to that water body), I feel it should be treated as wild. Once released, it is subject to the same vagaries of wild fish, which may or may not consist of previously released fish which have become established in the water body. Are not the whooping cranes considered wild, even though lot of them are based on released individuals?
A lot of this discussion is similar to discussions birders have about “countability”. Birders who are fanatics about “listing” the species they’ve observed have spent decades hashing out which introduced species can be added to their “life lists” and other personal lists.
The major birding organization in North America (the American Birding Association, ABA) decided that a bird that escapes or is released from captivity (say a pet parrot escapes in Winnipeg) is not “countable” on someone’s life list. Even though that escaped bird is subject to the same natural pressures as any other wild bird (finding food, avoiding predators etc).
The ABA decided the focus should be on bird populations rather than individual birds. Is the population self-sustaining or not? Determining this requires watching whether over a number of years the birds can not only survive but reproduce. In this way introduced populations eventually get recognized as eligible to add to people’s list. The problem with this is that it requires making decisions about populations that are highly location specific. An introduced species that’s countable in Texas might not be countable in Washington state etc. This would probably be difficult to apply to fish.
I’m not arguing that this approach be applied to iNaturalist or to fish, but maybe we can learn something from the discussion that birders have had.
http://listing.aba.org/criteria-determining-establishment-exotics/
https://bashakillbirder.wordpress.com/2014/09/30/california-condor-now-aba-countable/
Of course I think it’s fair to find the intensity of birder’s preoccupation with countability pretty ridiculous:
http://www.thebirdist.com/2014/10/changes-to-abas-recording-rules.html
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