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Aggressive pond fish

25 9:54:24

Question
QUESTION: Hi Robyn
I've had a 100 gal outdoor pond for a few years now and my 3 fish (2 sherbunkins) and a fantail have always gotten along very well. In the past few days the sherbunkins have started chasing the fantail - and will round her up into a shallow area of the pond where they can literally go underneath her and push her up and out of the water!
I would guess the sherbunkins are about 8" long - the fantail is a bit shorter but FAT FAT FAT and very slow ...
I was watching them today - and though she (the fantail - "Fanny") appears to still have all her fins and no visible damage; I'm really getting concerned that they might hurt her.
Do you think this is a spawning problem??
I could separate her (?) in a small area if this is just a seasonal issue - but she's a beautiful HUGE fish and I'd hate to see her hurt.
I'd sure appreciate any suggestions.
Thank you.
Lynn

ANSWER: It sounds like the fantail is a female, and the shubunkins are male.  You are describing typical spawning behavior.  Males chase females and can get pretty physical, jamming the female into things and slamming her around.  They can certainly hurt her especially since she's a fancy goldfish, and they're not.  But, females normally heal up pretty fast from spawning injuries unless the males eat off her fins which usually only happens in smaller confines.  The males eat off her fins because they're actually trying to eat her eggs as they come out of her; nothing tastes better to goldfish than goldfish eggs.  It's up to you if you want to separate them.  As long as it's warm, the males will be interested in her.

Good luck!

---------- FOLLOW-UP ----------

QUESTION: Thank you Robyn ...
One more question ... if the fantail is the only female in the pond - do you think if I could get a few "girl" shubunkins it would keep the "boys" away??
HOW CAN YOU TELL THE SEX OF FISH??
Thank you again.
Lynn

Answer
Yes, adding more females would lessen the burden on the other female.  How warm is your pond water?  You must be in a warm climate if the fish want to spawn already.  If it is still cold, then it might be just pestering and not spawning.  You can add a few female goldfish but, at the same time, you don't want to overcrowd your pond.  It should have room for a few more though.

My page on sexing goldfish is at http://www.fishpondinfo.com/gfish3.htm
If they are mature and "in the mood," it's easy for me to tell.  Males get little white spots all over their gill covers.  Females are more plump.  That page has more information.

Happy ponding!