Is it bad for fish in captivity to never reach their full potential?

[Hybridfish7]

I'm aware that they don't always in the wild, but is it bad for fish to go their whole lives in captivity without reaching their full growth potential? Obviously with things like RTC it's bad/worse, with them only getting 2-3 feet of their maximum 6 or whatever, but with things like cichla, dovii, or umbees, is it unhealthy for them to not reach the full 33-36+" in captivity, and instead max out at 2 feet or so?

 

[GlobalFishCo]

Its not always bad as longs you are meeting the tank requirement for the fish. If they are stunted do to their tank size/improper care then it would be considered bad. It also takes those fish lots of years to reach their full potential size.

 

[Friller2009]

You can also look on the flip side of this, fish in captivity being much larger than they are in the wild.

 

[Backfromthedead]

Im of the opinion theres no difference in potential for growth between aquariums and wild environments. In captivity, its all about the capabilities and dedication of the keeper.

Just take public aquariums for example. Idk if its still there but baltimore had the largest tautog ive ever seen in a roughly 10k gallon enclosure. In the amazonia exhibit of the national zoo there was once an arapaima 7'+ that i watched grow over the years, true monster.


I think if you were lucky enough to find the perfect genetic specimen and spared no expense or effort with its care, theres no reason you could not grow an umbee to 30"+.

 

[jjohnwm]

I think it would be relatively easy...not common, mind you, but easy...to get a small species of fish to live a longer life and achieve a larger size than many or most of its wild conspecifics. All it would take is diligent attention, throughout its life, to the basics of aquarium maintenance: adequate tank size, proper diet, regular water changes to maintain excellent parameters, correct temperature, lack of aggression or other sources of stress...all the basics. Sadly, even with small fish, I think that perhaps 1% of individual fish sold in the stores even live as long as a typical wild fish, let alone exceeding that lifespan.

All it takes is one lapse in any of these basic care requirements, and it's over. Since they can potentially live very long lives, that allows an ever-greater chance for something to go wrong at some point. Defective heaters, power outages, burst tank seams, accidental poisoning, unnoticed changes in source water parameters...any of those things can be detrimental or even lethal, and account for a certain percentage of early deaths. Far more are caused by cumulative stress brought on by over-crowding, water quality degradation due to insufficient water changes, aggression from other fish, substandard nutrition, disease brought in due to lack of quarantine...the list goes on and on.

With monster fish, the problem is magnified many times over. Even fewer of those fish will ever be kept in large enough containers to even approach their growth potential; they will live their "whole lives" in too-small tanks...the common euphemism is "grow-out" tanks, although many of them should likely be re-named "die-in" tanks. Very few of them will receive sufficient water changes. Another thread recently detailed the life of a small Goonch, which met an untimely death due to, apparently, a power outage. It lived "a solid 4 months". I did a double-take when I saw that: "a solid 4 months". When a fish that grows to several feet in length, and likely lives a typical lifespan of several decades at least, survives in captivity for four months and grows to a few inches...well, there's nothing "solid" about that.

Fish, like any other captive animal, are...or should be...a commitment.

 

[esoxlucius]

To be honest I think that fish have a better chance of reaching their full potential in an aquarium than they do in the wild. But all the stars have to align perfectly.

The major factor in the wild is predation, which of course in an aquarium is completely eliminated, with correct stocking of course. That factor alone gives the fish a great chance of maturing into something spectacular.

But as jjohnwm said it is then up to the individual hobbyist to provide the best care possible for the full duration of the fishes life, and even if they do they also need to have a fair bit of luck too with regards to things happening out of their control, such as power outages, seam bursts, significant and sudden source water changes etc etc etc.

If all the stars align then who knows?

What puzzles me is that when they state the lifespan of any fish on websites and at LFS's, how can the people who've come up with that age in the first place be sure? Take the Bala shark as an example. 10 years or thereabouts is the age touted about. Who closely monitors Bala sharks in the wild from juvenile to death to come up with that figure? And the Bala example applies to all the fish we keep.

 

[Hybridfish7]

To be honest I think that fish have a better chance of reaching their full potential in an aquarium than they do in the wild. But all the stars have to align perfectly.

The major factor in the wild is predation, which of course in an aquarium is completely eliminated, with correct stocking of course. That factor alone gives the fish a great chance of maturing into something spectacular.

But as jjohnwm said it is then up to the individual hobbyist to provide the best care possible for the full duration of the fishes life, and even if they do they also need to have a fair bit of luck too with regards to things happening out of their control, such as power outages, seam bursts, significant and sudden source water changes etc etc etc.

If all the stars align then who knows?

What puzzles me is that when they state the lifespan of any fish on websites and at LFS's, how can the people who've come up with that age in the first place be sure? Take the Bala shark as an example. 10 years or thereabouts is the age touted about. Who closely monitors Bala sharks in the wild from juvenile to death to come up with that figure? And the Bala example applies to all the fish we keep.

I also question the true lifespan of an umbee being 8-10 years. Not knocking umbee keepers, but you can't expect your fish to live as long as it can when you're feeding it the fattiest, most protein rich foods with little to no space for exercise, solely in hopes of getting them to a certain size as fast as possible. I have seen big umbees in good health, but they seem to deteriorate very quickly at a certain size.

 

[Backfromthedead]

Another issue is that great size can actually be quite a hindrance in the wild. Very old black drum, for example, can reach over 100 lbs max and are relatively frequently caught in the 40-50 lb. range. These are almost always released though (or should be) because large old drum are almost always rife with a variety of parasites. The "sweet spot" that most are angling for is just over the legal limit, 10-15 lbs--younger individuals with clean, tasty flesh. At some point when growing they become obvious targets for parasites due to either their size or how it affects their behavior.

Of course, if well managed, a captive drum would not face any of the detriments that parasites bring. Goes for any fish in at least some capacity i suppose.

 

[PhishMon84]

i agree with most written above except this piece "Sadly, even with small fish, I think that perhaps 1% of individual fish sold in the stores even live as long as a typical wild fish, let alone exceeding that lifespan. " Just looking at the average brood size for many of the species we keep, it's obvious their reproductive strategy is like the buck shot approach, meaning they throw so many young in the hopes that a few survive, some will be cannibalized others preyed upon by other species or pairs of the same species and that's just cichlids.

egg scatters like tetra or bichir have even less parental care and I'm guessing the wild fry mortality rate is north of 95%.

we aren't doing it perfectly but i think we have eliminated enough of nature in our tanks to give them longer than average lifespans.

Also line up 100 men or women the same age and you will have wildly different terminal sizes, with very few max or min sizes and you DONT manage to the exception.

 

[jjohnwm]

i agree with most written above except this piece "Sadly, even with small fish, I think that perhaps 1% of individual fish sold in the stores even live as long as a typical wild fish, let alone exceeding that lifespan. " Just looking at the average brood size for many of the species we keep, it's obvious their reproductive strategy is like the buck shot approach, meaning they throw so many young in the hopes that a few survive, some will be cannibalized others preyed upon by other species or pairs of the same species and that's just cichlids.

egg scatters like tetra or bichir have even less parental care and I'm guessing the wild fry mortality rate is north of 95%.

we aren't doing it perfectly but i think we have eliminated enough of nature in our tanks to give them longer than average lifespans.

Also line up 100 men or women the same age and you will have wildly different terminal sizes, with very few max or min sizes and you DONT manage to the exception.

Point taken, and well made. I should have clarified that I was referring to fish that were past the fry stage; comparing newly hatched lifespans would likely skew the results hugely in favour of aquarium fish.

I meant fish that are of saleable size, such as might be typically purchased in a LFS, compared to equivalent young fish in nature. And, agreed, calling it 1% might be a wee bit of an exaggeration, considering that predation remains a danger for wild fish at all sizes. My wife claims that I exaggerate...but I know that that is a complete, bald-faced, totally fabricated piece of fiction that has absolutely no basis in fact, ever...

My negative take on this is based largely upon my years working in a pet/fish store as a youngster. I'm sure everyone is familiar with the adage that 10% of the fishermen catch 90% of the fish; based upon what I saw working in that shop, it appeared as though 10% of the aquarists killed 90% of the fish. We had a few regular customers who came in regularly for supplies and to snoop around; they were experienced people who would occasionally buy some fish, usually when they found something that they had particularly been searching for. I would chat people up whenever I had a chance, and that small sub-set of aquarists brought fish home and kept them alive for extended periods, often many years.

But...there was that small cadre of keepers who just bought, bought, bought...and kept buying. If asked how the XYZ fish they bought the previous week were doing, it was usually something like "Oh, they did really well for a few days...but then they jumped out"...or got sick and died...or got eaten...or were killed by something else...or whatever other tragic ending you can imagine. A good chunk of those fish were probably medicated to death; these same folks tended to buy fish medications in staggering quantities; this was back in the days of yore when such meds were still available in Kanada.

When you are dealing with a customer who has, by his/her own admission, 1 or 2 aquariums...but who buys dozens or even hundreds of fish each week...for months at a time...it tends to sour you on the hobby.

So...I agree that "we", as aquarists, can provide conditions good enough to ensure a long life for our charges...but I just don't think that enough of "us" are doing that.