Bob's Fish Tank:
The two red tailed shark have paired in an odd way.
Many fish breeders report that red tail shark do not get along as mates and rarely breed in captivity. They are aggressive, territorial and often loners.
These two red fin sharks have taken to a strange ritual of swimming side by side with short jerking motions for a few seconds.
Then, the smaller one will act submissive and let the larger one take dominance. They will both shimmy together like swimmers in synch. Sometimes, they face opposite each other (69 position).
The top fish is about 1 3/4" long and the bottom fish measures nearly 2".
During their strange ritual, the smaller fish will often float standing up, as if she/he were letting the other know she/he is available and willing.
When they dance together, they swim in unison for a few moments and break away. This performance goes on every few minutes at a time. Then, they swim off on their own and help keep the fish tank clean.
These fish have only been together for 5 days. They came from thew same PetSmart fish tank on Monday, started dancing on Thursday through Friday.
Update: the day after observing this possible breeding foreplay, the larger black shark has become fatter and more rounded at the bottom. This larger fish has become more aggressive to the smaller one and now just chases the smaller fish around instead of flirting. She may be pissed off that she got pregnant!
Watch more fish behavior in my tank.
Video by R. Zucker. 2007 Copyright.
Red Tailed Black Shark
