Blooood...

[thejeff]

2) Jade Knife helps with blood sacrifice, not hunting. Sanguine dowsing Rod is what you want. Higher the blood level the better the hunter, but there are diminishing returns. If you've got cheap B1 mages it's usually best to use them with a Rod than use a more expensive mage.
The general rule of thumb is 3 B1+Rod hunters per province.
Unrest figures in, so lowering taxes or patrolling helps. If population is under 5000 you also get less, so it's best to hunt in provinces far enough above 5000 that they'll last awhile (dependent on scales/unrest/patrolling) but low enough that you're not losing too much income.
As far as I know, returns only drop over time as the population drops.

[Kheldron]

A commander with no blood lvl has a 10% chance of success
a lvl1 50%
a lvl2 90%
a lvl3 and more 100%

[GrudgeBringer]

That is EXACTLY what I needed to know...thanks guys!!

[chrispedersen]

Grudge,

there are three checks involved in blood hunting. Keldron mentioned one.

Population / 50 as a % is another. so 5000 people you will always pass this check.

finally, the last check is:

If you succeed at a check you have an unrest/4%chance of losing it due to unrest.

So, keep your unrest low, use as high a blood hunter as you can, in a population of 5000.

As someone else responded - blood sites are much lower in frequency than other sites. personally, I never bother casting
bowl of blood.

Off the top of my head almost all the common blood sites do not give you blood - they give you gems. Additionally one of the more common blood sites just incites unrests and gives you villains.

But if you review the blood sites on edi's database, you will find it instructive.

OH. One other thing: Your blood income is tied to magic site frequency as well. Ie., you earn less LA than you do Ea.