can you see him?
These fish live in the bottom not on it and that is why I believe they are more susceptible to heavy metals and other toxins in the substrates of rivers, if we want these fish to be there in the future we must make sure the rivers are clean not just the water but the mud and detritus that forms the bottoms of our rivers.
Blue gums are becoming favourites for the killing off of these fish if the run off of pesticides or herbicide’s is not killing the fish it could be killing the food i.e. plankton and other invertebrates which the fish rely on as there staple diet, in the cold waters of the southwest yabbies are not as common as in northern parts worms and insects play a part but plankton is by far there biggest food source.
I believe this to be one of the greatest videos of fish ever taken, captured at a moment in time and the bigger fish looking on was it thinking of eating the smaller fish I don’t know.
These fish must be saved and I call on the authorities to carry out the work necessary ie toxicology test on river substrates to determine if there are toxins in the rivers that are killing these fish.
Find the cause reverse it what ever it is, these native fish deserve a future and it is up to fisheries to do this work no one else can, and then implement the findings after all fisheries can take your boat off you if you catch a fish under size but cant stop whole sale slaughter by toxins entering the water system.
These fish were they runts of the crop so I isolated them and hand fed them, just look at them now, runts of the crop would have a hard time in the wild but here they thrive .
The middle fish is between 5/6 inches long and I will keep him until fisheries have had a look and then I will sell him, I would like to get $100 for him given his size.
This is my one hundredth blog post and I was trying to think of something impressive to post but on thinking about it I would just like to reemphasize why I am breeding and now growing river blackfish or if you like Gadopsis Marmoratus I have spent tens of thousands of my own money to first find a way to breed them and second to grow them out I have had no help from anyone except my family and local farmers, I expect to have over three hundred fish this year enough to re-establish a breeding population in a local river or lake but so far the permit from the authorities is not there i will keep trying.
I did however find some winter yabbies for the fish,
I found this yabbie while getting some muck out of the no 1 pond as you can see it could only be days or weeks old, it shows that nature provides food for the fish that are coming and also that the environment that I have created is working well and is as close to natural as possible all good signs for a bumper crop of young blackfish in a couple of months. It also shows us that while we thinks every thing switches off during the cold that’s not so , the mother of this yabbie must have mated around mid winter interesting?
The top photo is a aquaculture tank that I bought from poly tank, they have a sloping bottom to allow leftover food and other waste to leave through the outlet pipe located at middle bottom and they work fine however the one issue I had was scum on top of the water was not being extracted so I extended the pipe to a level above the water line and put some holes where the scum could then leave.
The second and third photo,s show a black pipe near the roof of the green house this pipe has a hose bayonet at each end this allows me to fill it with water this water in turn warms from the sun and I can then use that water to warm the water in the ponds outside.
The people who read this blog and would also like to breed blackfish must keep in mind when you are trying to do something for the first time like breed blackfish you must keep an open mind and be willing to try different things.
Don’t forget these are native animals and permits are required so talk to your state authorities before you start, in particular places there could be a different strain of blackfish so make sure you know witch one is yours.
And if I could give you one more piece of advise aerate,aerate,aerate.
The cement blocks that I placed into tank no / 3 have been accepted as a suitable breeding place. I have seen fish in them and it is my opinion that they are getting ready to breed in the hollows that I created with the blocks, you have to sneak up at night with a torch and you will see this behaviour, in that sense they are truly nocturnal all of the important things are done late at night.
I am going to see if I can catch a female laying her eggs on camera this will be tough they may perceive the camera to be a threat and push it away or go elsewhere to lay the eggs but I will give it a go.
It has been speculation of mine for some time that blackfish have a way of repopulating a stream relatively quickly they must be able to do this to survive the boom and bust of the Australian climate and it could be that the ratio of females to males is high this would allow a single male to fertilise more than one females nest however this would mean that the male does not stay with the eggs at least not on a permanent basis he may be called on from time to time to defend a nest from intrusion including from people/ researches this could have been the reason researches believed that the males stayed with the eggs.
for this reason I am adding more nesting boxes to my ponds and also to accommodate maturing females who will lay eggs for the first time this year, the breeding season starts in around two weeks and I will be ready.