Handfish-spawning

[Image appears of a diver going in to the water and text appears: We are helping to conserve the critically endangered and rare Spotted Handfish, Hobart, Tasmania]

Narrator:  Today’s very much a landmark day for the CSIRO and the handfish. 

[Image changes to show divers swimming in the water]

We managed to collect a pair of handfish from the river. 

[Image changes to show a Spotted Handfish in a tank and the camera zooms in on the Spotted Handfish]

The handfish are one of the rarest fish in the world and one of the most critically endangered fish in the world.  They are only found in the Derwent River here and they’re pretty much Hobart’s iconic fish although a lot of Hobartians actually don’t know that.

[Image changes to show Tim Lynch talking to the camera and text appears: Tim Lynch, Senior Research Scientist, CSIRO Oceans and Atmosphere]

Tim Lynch:  So this looks like courting behaviour is starting to occur. 

[Image changes to show the male handfish moving up to the female handfish]

The male’s moving up towards the female and the female looks like she’s dipping her fins over towards the male and you can see they’re circling each other.  They’re lifting their hands up and putting them back down again.  This is quite active for a spotted handfish.  Usually when we see them in the wild, they’re very still and I think they’re trying to hide from us but they seem to be very relaxed in this tank and they’re engaging in what looks like courtship behaviour. 

[Image changes to show Tim Lynch talking to the camera]

Alright, so we just witnessed them spawning.  So, what it looks like is happening is I’d say it almost looks like internal fertilisation which is really unusual for a fish and I don’t think this has ever been captured before. 

[Image changes to show the male handfish underneath the female handfish and the image shows them moving around the ascidian and then the camera zooms in on the female laying the eggs]

So, the male is underneath the female and they’re going up around that ascidian and what I think is happening is he is injecting the milk into the female and then that’s fertilising the eggs and she’ll continue to go around that ascidian and weave those eggs onto the stalk. 

[Image continues to show the female handfish moving around the ascidian with the eggs and then the camera zooms out to show the male handfish looking on]

We have seen multiple fish around egg masses before but what looks like happening here is that the male is leaving the female alone and going off and doing his own thing.  So, we don’t have great information.  This has hardly ever been seen. 

[Image changes to show Tim Lynch talking to the camera]

This is the first time anyone has seen this, this century but what it looks like is that it’s the female that’s doing the parental care but we’ll keep close watch on this egg mass over the next couple of weeks to see what’s actually happening.

[Music plays and text appears: Thanks to our partners: National Environmental Science Program (NESP), Zoos and Aquarium Association (ZAA), SEA LIFE Melbourne Aquarium, Seahorse World Tasmania, University of Tasmania]