A commercial yabby pond
Commercial yabby pond

Commercial yabby pond

Semi-intensive commercial yabby farming produces quantities of yabbies at far higher densities than occurs naturally in the wild. Ponds are built to specifications that suit the yabbies, shelter is added and food is supplied. All this is inducive to growing large numbers of yabbies quickly.

Now the yabby Cherax destructor is one of the few species on this planet that is increasing its area of domination. I know you can google it and the International Union for the Conservation of Nature Red List shows the species as vulnerable but that’s not the case. Yabbies are a robust species with an instinct to wander and distribute. They are a migrating species and can migrate on mass. It’s extremely easy and common at night when you get a bit of rain to have yabbies leave the pond they are in, and go a wondering all over the place. They can travel long distances overland and survive for days in wet grass. The larger the yabbies and the higher the density of yabbies in your pond, the greater the chances of wondering occurring.

Perimeter fencing of your ponds is essential for semi intensive production of yabbies, you don’t want them to wander from the pond.

There are a number of choices for perimeter fencing (you can see more options in The Commercial Yabby Farmer book) but this article is on a fence use in a high fire risk area.

METAL FENCING

This article is based on a property that adjoins a state forest that is subject to regular bushfire so the metal fencing has the  benefit of being fire proof compared to say “silt stop barrier” or “poly” fences.

Materials:

0.48mm Trimdek or equivalent roofing sheets (many crayfish farmers use corrugated iron).

40 mm x 0.55 mm Top Hat Battens

Hex head Screws

 

Equipment:

Battery drill

Battery grinder

Sledge Hammer

String Line

Full 6 metre sheets of trimdeck are purchased and this farmer cut them in half down the middle with a hand grinder. This gives you two sheets roughly 400 mm wide. Normally farmers would not cut the sheet in half but use the full sheet. Top hat battens are cut at 750 mm lengths to suit the half width sheets.

Cut the top hats battens up wiith a grinder

Cut the top hats battens up with a grinder

Cut into 750 mm lengths

Cut into 750 mm lengths

Just use a string line to work out where the fence is going

Just use a string line to work out where the fence is going

Hammer in the battens at 2 m intervals -it doesn’t matter if the top gets bent or deformed from the hammering.

Hammer in the battens at 2 m intervals -it doesn’t matter if the top gets bent or deformed from the hammering.

Overlap sheets

Overlap sheets

Affix the sheets to the battens with hex head screws

Affix the sheets to the battens with hex head screws

Sheets affixed to battern

Sheets affixed to battern

When you need to go around a corner - affix one end

When you need to go around a corner – affix one end

Cut the ridges with your grinder and bend

Cut the ridges with your grinder and bend

Cover the cut corner with a top hat batten (Usually a shorter one)

Cover the cut corner with a top hat batten (Usually a shorter one)

Just bend sheets around corners

Just bend sheets around corners

Get some soil or gravel and add a little around the base of the tine to fill any gaps under it

Get some soil or gravel and add a little around the base of the tin to fill any gaps under it

Soil or gravel along the base of the metal also helps stabilize the fence

Soil or gravel along the base of the metal also helps stabilize the fence. Unfortunately, with this minimum height fence you have nothing available to dig below ground and bury. 

As a consultant I recommend “poly” fences and that you bury at least 100 mm in the ground. Please note that most State Fisheries Departments have a mandatory requirement that the perimeter fence is “imbedded in the ground”. They also usually have a min height requirement (typically 600 mm high)- please check the regulations before you do anything.

Cheers

Rob