My question for wild colonies is why do many of them appear black? ARe they German decent or are they what?
Yellow isn't a 'true' honey-bee colour, but results from the complete absence of melanin, in the same way as blue eyes and blond hair result from the absence of melanin in humans.
Melanin is produced from the amino acid tyrosine, with the biochemical pathway from tyrosine-to-melanin containing approximately 6 steps. In the honey-bee there are 6 genes (known as the polygenes) which, when homozygous (that is, an allele pair being identical) operate as inhibitors at each step. Thus, if 3 (say) of these genes are homozygous, a brown bee will result, and so on ... Zero homozygous polygenes will result in black.
So - with their very mixed parentage, honeybee mongrels have very little chance indeed of having all 6 polygenes homozygous, so yellow mongrels are rarer than rocking-horse poo. For all intents-and-purposes then, feral bees are invariably black, as black is dominant over every other colour, including yellow.
Interestingly (perhaps ?), in addition to the 6 polygenes which create the various shades of colour, there is also a 7th gene (b1) which codes exclusively for black, quite independently of the polygenes. This gene produces black or not-black (not-black being a function of the 6 polygenes) in a true Mendelian way - so it can be used with 'golden' stock as a tool to demonstrate purity of that particular genetic line.
Hope this helps.
LJ