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.

[wpvideo R4cP5baF]We got thirty two mils of rain overnight and rain is lways welcome as well as helping out fish farmers it also puts much needed water into lakes and rivers around the area.

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.

The water that flows to this point comes from the roadside which in turn picks up farm run off. This sand was the lake bed and due to low rain fall and extractions through bores is now part of the foreshore so what’s in this water, dog poo, cow poo oil and grease from the road, the sand has been lake bottom for hundreds or even thousands of years in that time it has picked up and stored tons of  assorted nutrient, now nutrient is a good thing when you are trying to grow something but the last thing we want to do is grow something in Lake Bullen Merri enough bad things grow there already.

Now if we had got of our behinds this could have been fixed in fact it could have acted as a natural filter a bio filter a few rocks some water loving plants and bingo we have a filter.

But know as of this morning nothing has been done and big rain is on the way this will erode more sand washing tons of nutrient into the lake and this will make a blue green algae event all but certain this season closing the lake to boating and fishing costing local shops and accommodation places and  petrol stations hard to come by dollars.

what frustrates more is how easy it would be to fix in fact when I was there this morning they had been doing works further along the bank.

UPDATE: The water temp in tank 3/4 has improved to over 10 degrees if this continues I would expect breeding to be early again this year, that would be young fish mid Dec. some people tell me that they only view this blog on Facebook if you wish to see all the photo’s you should click on the link at the bottom of the screen and go to the blog.

My fish (gadopsis marmoratus ) or river blackfish are enduring very cold water at the moment around 7.6 degrees and doing very well this raises the question should we consider river blackfish for reservoirs in cold areas where Murray cod are not performing .

Blackfish are the only native fish that is viable in these cold dams and I believe if we want to catch native fish in the southern parts of Vic that are good eating and good to catch then there is no alternative.

ps We can now breed them in captivity I know this because I have done it.

Well over half of the original fingerlings have made it to freedom they now reside in pond no 4 where they can stay until they are old enough to breed. may I take a moment and say how pleased I am with myself I am a amateur fish breeder I have had little or no formal education in this business and to produce these fish is very rewarding I am going to have a beer. ps its a shame they are not going into a river for others to catch.

This is the bird netting we have to have, there are loads of cormorants and other fish eating birds around here and I am not going to put last years fish in a dam only to have birds feeding on them At this end there will be a walkway when I get around to building it.