[color=#006600]CarloT[/color] wrote:
ok. so when were fish that are 13cm now born?
Difficult question to answer without more info - eg. exactly where is this farm dam, how big is it, how deep, what aquatic vegetation is there, what other fish are there (fodder fish base), when was it stocked with Bass, also how many Bass were stocked, what size and shape of Bass (condition) have you caught there before etc, etc?
The growth rates in my previous post were "optimal" growth rates under conditions which could be considered ideal.
Remember that not all Bass will spawn at exactly the same time. Certain Bass may spawn early (especially in smaller bodies of water (such as farm dams) which warm up sooner. Later cold snaps may then be detrimental to fingerlings which spawned early. In certain areas, Bass may be on the nests as early as July, in other areas as late as October ...
If conditions are not ideal or optimal (eg. overpopulation, no suitable fodder fish base, early warm weather inducing early spawning followed by severe cold snaps later on), you will get "runts" or stunted growth in Bass.
Fish management in smaller waters, such as farm dams, is critical (see
http://www.pondboss.com). Many farm dams are not managed properly. The farmer stocks some Bass fingerlings (once), usually without first establishing a fodder fish base, and you end up with too many small Bass competing for the same food source, resulting in stunted growth (characterised by Bass with rather large heads out of proportion to lean (emaciated) bodies (and sunken stomachs). A well-fed Bass should be shaped like a rugby ball!
Also remember that some "fodder fish" especially Blue Kurper (Mozambique Tilapia) and Redbreast Kurper/ Tilapia can, in smaller waters, pressurise and "outcompete" Bass! You need to manage the fodder fish too! Never stock Catfish (Barbel) or Carp with Bass, especially in smaller waters. Try to remove as many Catfish and Carp as possible. Yellowfish (Scalies in KZN) and Trout with Bass are OK. The smaller Trout (up to about 20 - 25cm) are excellent Bass fodder!
In a new water, it is probably best to start with minnows (ghieleminkies) - stock them first 3 - 6 months before stocking Vlei Kurper (Banded Tilapia) and Dwarf Kurper. Let them get established for 6 - 12 months BEFORE stocking Bass fingerlings. You would then be able to expect optimal growth rates from the Bass! If you want the ultimate in Bass size and are situated where Trout can survive, stock (15 - 20cm) Trout as well at least every year - they make great high protein snacks for Bass! You must manage your water and the fish populations of both Bass and the fodder fish. For more info, see
: http://www.bigbass.0catch.com/id8.htm