Are my Silver Sharks pregnant / full of eggs?

[Robb Bloomfield]

Hi,

Noticed last night that one of my silver sharks, and to a lesser
extent, two others, have swollen bellies. The fourth shark is slim and
sleek looking still. Do they produce eggs in large quantities which
are then fertilised by the male? Are they carrying fertilised eggs?
Are they carrying live young? Are they just fat :)

The only info I could find on the web said they were difficult to breed
in captivity - i couldn't find anything else.

[NetMax]

"Robb Bloomfield" > wrote in message
oups.com...
> Hi,
>
> Noticed last night that one of my silver sharks, and to a lesser
> extent, two others, have swollen bellies. The fourth shark is slim and
> sleek looking still. Do they produce eggs in large quantities which
> are then fertilised by the male? Are they carrying fertilised eggs?
> Are they carrying live young? Are they just fat :)
>
> The only info I could find on the web said they were difficult to breed
> in captivity - i couldn't find anything else.


Whooo, egg-bound Silvers? That's awesome. How big are they? To answer
your questions, they produce eggs, in what I would suspect to be fairly
large quantities, which are externally fertilised by the male. By
actually looking I might be able to better guess between fat or
egg-bound. *calm calm*

Let's first establish that your Silver sharks (or Bala Sharks or Tricolor
sharks depending on where you live) are actually Balantiocheilos
melanopterus (Bleeker, 1951) by checking these links.
http://www.aquariacentral.com/species/db.cgi?db=fresh&uid=default&ID=0487&view_records=1
http://species.fishindex.com/species_2895balantiocheilos_melanopterus_bala_shar k.html

If eggs, then the edge closest to their tail where the eggs start will be
much more well defined, than if it was just a fat fish. Note that
getting the females full of eggs is still a long way from a successful
spawning, but it's a lot closer than if they had no eggs ;~). The next
thing you'll need is a big tank (and lots of vegetation, increase the
water temperature while dropping the pH, dance the wild coyote to Mel
Tourme... oops, better stop before someone thinks I know what I'm talking
about ;~).
--
www.NetMax.tk

[Robb Bloomfield]

Well, the three fat ones look like this:
http://www.aquariacentral.com/species/db2.cgi?db=fresh&uid=default&ID=0487&picture_page_view=1
And the other one looks like this:
http://species.fishindex.com/photo_2875balantiocheilos_melanopterus_bala_shark. html
So maybe they're just growing up fast?

[Nikki Casali]

Robb Bloomfield wrote:

> Well, the three fat ones look like this:
> http://www.aquariacentral.com/species/db2.cgi?db=fresh&uid=default&ID=0487&picture_page_view=1
> And the other one looks like this:
> http://species.fishindex.com/photo_2875balantiocheilos_melanopterus_bala_shark. html
> So maybe they're just growing up fast?
>

Compared to the larger sharks, the thin one looks emaciated. Is it
eating as much as the other two? I've never seen an adult Bala Shark so
thin. Were the other ones as thin as the fourth before?

If the others are really pregnant then you are one lucky fish keeper. I
can only presume the fourth has been a very, very busy fish indeed!

Nikki

[Robb Bloomfield]

They were all kind of sleek looking :)

I just happened to notice Sunday night that one was plumped up and the
other two were getting there, so it must have been sudden, I did a
water change saturday morning and I'm sure I'd have noticed then.....

They're all eating happily, they're the happiest and friendliest fish
in the tank, they even play with my lonely platy now and again....

[Margolis]

I here I thought we were talking about Silver Sharks aka Arius Jordani. I
have never heard of bala's being called silver sharks before, oh well.

btw, that second one look emaciated. There's something wrong there. If
yours looks like that I would look into the cause. See if he is getting his
fair share of food. Hopefully that is the only problem. If it seems that he
is getting enough and his belly bulges at every meal then he may have an
internal parasite which is not a good thing.


olis
http://web.archive.org/web/20030215212142/http://www.agqx.org/faqs/AGQ2FAQ.htm
http://www.unrealtower.org/faq

[NetMax]

"Nikki Casali" > wrote in message
...
>
>
> Robb Bloomfield wrote:
>
>> Well, the three fat ones look like this:
>> http://www.aquariacentral.com/species/db2.cgi?db=fresh&uid=default&ID=0487&picture_page_view=1
>> And the other one looks like this:
>> http://species.fishindex.com/photo_2875balantiocheilos_melanopterus_bala_shark. html
>> So maybe they're just growing up fast?
>>
>
> Compared to the larger sharks, the thin one looks emaciated. Is it
> eating as much as the other two? I've never seen an adult Bala Shark so
> thin. Were the other ones as thin as the fourth before?
>
> If the others are really pregnant then you are one lucky fish keeper. I
> can only presume the fourth has been a very, very busy fish indeed!
>
> Nikki


LOL, I don't think the 4th's condition would reflect much on the
condition of the other three, or even on his own condition unless he is
so amorous as to spend all his time giving chase.

In regards to the thinnest, this pic shows a thin but healthy Bala.
http://badmanstropicalfish.com/barb-pictures/bala_1.jpg
Although a juvenile, anything thinner than this and I would be worried.
Balas travel very poorly. This and much worst is how they arrive in
North America. I would always quarantine Balas for 2-3 weeks before
selling any, and this picture is what they looked like at the end of
their quarantine. If you have had yours for more than 4 months, then
they should be fatter.

This one is probably more representative of an older specimen in good
condition.
http://www.sd53.bc.ca/TimeCapsule/TENMTC/PageGraphics/Fish%20Pictures/BalaShark.jpeg
It's normal for their height to increase with old age (how old are
they?).

Some trivia: according to fishbase:
http://www.fishbase.org/Summary/SpeciesSummary.cfm?ID=6089&genusname=Balantiocheilos&speciesname=melanopterus
these characters are on the IUCN endangered list
http://www.redlist.org/search/details.php?species=2529
Considering their origin is exactly where the Asian tsunami hit, you can
bet that they took a big hit.
http://www.scalare-online.de/aquaristik/db_fische/cypriniformes/cyprinidae/Balantiocheilos_melanopterus_map.JPG
Other pics I've seen of the fish life that got destroyed have been
remarkable. In particular, the Balas are susceptible to water
conditions, and their water took a bit hit in terms of salinity, clarity
and all the smaller creatures which they feed off of (which are even more
fragile).

If you do see them scattering eggs, take note of the water parameters
before and after the event. There are always hobbyists trying to breed
fish, and extra effort is put on the ones which are redlisted.
If your German is up to it
http://www.scalare-online.de/aquaristik/db_fische/cypriniformes/cyprinidae/Balantiocheilos_melanopterus.html
does a good overview. Unfortunately the English translation is a bit
choppy.

Watch the scroll on the links.
--
www.NetMax.tk

[MarAzul]

"MarAzul" > wrote in message
news:DLbMd.27552$xt.7417@fed1read07...
> Balas are endangered and almost extinct in the wild. The majority of the
> hobby sharks are captive on farms because of this.

Hehe... that was supposed to be "captive bred on farms"

I used to work at an
> aquarium and they had a great fact sheets about it...
>
> Mar
> ---------
> Vet Tech student

For those of you interested... 2 sites that talk about Balas and other
endangered fish..

http://rmbr.nus.edu.sg/biodiversitii/bio/aquarium_more.html
http://www.fishinthe.net/html/section-viewarticle-44.html

[Mean_Chlorine]

>Balas are endangered and almost extinct in the wild. The majority of the
>hobby sharks are captive on farms because of this. I used to work at an
>aquarium and they had a great fact sheets about it...

The bicolor shark is even extinct in the wild.

The bala, like the bicolor and the pakistan botia and a *bunch* of
other fish are facing extinction because of the booming asian
population and associated problems (development, water shortage,
pollution, overfishing, etc etc etc).

However, to the best of my knowledge, bala sharks have never been bred
in captivity without hormone injections, so it is highly unlikely that
the OP will get a bunch of bala babies.