Yabby for lunch

I am getting some great video of the blackfish in the aquarium recently , he has gotten used to me being around and will feed while I watch .

In this video we see him take a yabby on the second bite and then struggles to find his pipe I think because the lights in the container where on .

We can safely say that you would not want to be a yabby anywhere near a blackfish.

i am stunned that their growth rates are so slow ( given the food this one eats) perhaps the lack of high protein food such as yabbies and moths in their natural enviroments  are a factor.

I am going on a field trip to Tassie soon and we know that Gadopsis marmoratus grow to much larger sizes down there( up to eight kilos) and we also know that they have access to much bigger crustaceans, it will be interested to see for myself hat foods are availiable.

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Ghost fish

This is a video I got from a trail camera in one of my ponds well not in the water, Travis Howson and Ty Matthews are placing cameras in the water I decided that I would place them outside and put a see through panel in the tank, I have had it running for about ten days now and these are the results.

The first video shows the see through panel with two pygmy perch swimming around.

sorry about the wind noise, some parts of the country are in drought not here its been raining since May and cold to.

 

The second video show the ghost , he is in the far top right corner, this is taken with infrared but he looks like he can see the light, notice also the coating on his eyes this enables him to see at night.

Where is the weirs

I have long argued for more small natural weirs to be placed in some waterways to hold back water in the creeks throughout the dryer months , especially the Cooriemungle and Scots creeks, this would allow enough water to sustain blackfish and other small fish until the rains came again.

This could be achieved with fallen logs or rocks and would cause minimal damage to surrounding riparian vegetation .

This is good example it was probably constructed when the original bridge was built to slow the water during construction.

I don’t think it looks bad in the environment, moss and algae grow over it and it blends in quite well.

One of the arguments against weirs is that they would constrict flow for other species , I say what other species.

 

Hatchery

I have been asked on several occasions now that I should start a hatchery here at the farm, firstly there are several different types of hatchery , without going to boring detail  you have open systems and closed system and a variety in between .

To breed a fish you first need to understand that fish and sadly we know very little about blackfish breeding

In my experience if you take the eggs off the fish minder( the litriture says thats the male fish) the eggs  die, so if we don’t know that how can we start a hatchery .

The very definition of a hatchery is to breed fish, so how can we breed fish when we know so little about them , that’s born out by the recent trials by Travis Howson who is filming the fish in the wild to try and ascertain just what does go on during mating.

It is a disgrace that after nearly two hundred years of knowing of these fish we know so very little about them , where is fisheries, growing trout , a blow in from Europe, what about native fish , where is there concern for this very Australian fish.

I am Australian to my boot straps and I will not see this fish disappear on my time here.

Trout it seems can be released anywhere you like, they have recently released a tiger trout into lake Purrumbete how long before this fish is in the Curdies river killing remnant blackfish.

Below is a short video of a blackfish taking a yabby , have a look at the colours and notice the similarities to Murray cod . if Murray cod are legends of the north then blackfish are like the ghost fish of eastern Australia .

Do we seriously want to lose this fish . if the policies of the managers of our waterways dont start to give their full attention to these fish I can only conclude that they want to troutafy the state of Victoria to the detriment of all other native fish.

Believe me i am on the phone to local and federal Government people all the time but they dont seem to care.

 

 

Grub time

One of the foods that Blackfish like is grubs this type of grub are found in dead or dying wood , they like them either as grubs or later on as moths , they have several common names so I wont bother trying to name them here.

 

it takes a while until the fish will trust you enough for them to be comfortable to show themselves, but with time and food they will become just like puppy dogs, I am not sure this will lead to good breeding habits but I believe when people get to see what a great fish they are more people  will want to protect them , just have a look at the colours , we really need to start calling the something other than blackfish, (southern marbled cod) maybe.

The fish finally sees the grub and its all over in a flash.

Note the blackfish  poo just in front of the pipe in the second video.

Spring

Spring is the time we need to think about food on the farm, we need food for adult fish as well as any young fish that are to come, brood stock fish are just starting to get active and are looking for more food , I have found that the brood stock that I have will not take artificial foods ( young fish may if started early ) so I must have natural food ready , yabbies and worms make up most of the diet this time of year later on crickets and grasshoppers along with moths that come along around April .DSCF4140  The small yabbies below are best for 1, 2,3 year old fish ( as well as black bream )DSCF4142 This yabby is the best size for the larger brood fish.

DSCF4146   Here I am checking a net for yabbies, you can see in the background lots of long grass and weeds , insect swarm to these and the odd insect falls in the water and also becomes food. I did cut the grass one year because there was a snake living in it .DSCF4145   The young fish I hope will be along soon will need food as well , here I am below checking for plankton and copepods along with water fleas and other assorted bugs. I also have a theory that if the food for the young fish is not present in the broods ponds in sufficient quantities then the brood fish may well suspend breeding for the year , this is not unprecedented in Australia Kangaroos do a similar thing , last year we had no heat and little sunshine in October ( necessary for plankton growth ) this inhibits breeding. The winter this year has been long, cold and wet heres hoping for a warm spring , we all know some places are struggling for rain and we hope it rains for them  soon.DSCF4151

I would like to thank Rob Beavan for the photos.