Featured Cross: Backcrossed Olive Eggers (BC1-BC4ish)

Description

Backcrossed Olive Egger Pairings (Backcrossed, not Outcrossed!)

Our olive egger pens are under constant rotation. For Spring 2025, we’ve put all of our olive eggers back under our heavy bloom Black Copper Marans males— our Purple Coppers— in a breeding strategy called “backcrossing”.

Backcrossing is a strategy that condenses traits in one genetic line of birds. You are backcrossing an olive egger if you place a daughter hen back under her actual father, or a mother hen under her actual son. You are not backcrossing if you take any bird and place it under another genetically-unrelated bird, even if you know the olive egger was made from (unrelated) Marans.

Why? Because the latter is a first generation outcross, a new pairing that mixes the genetics of two separate lines. Outcrosses are gambles, you’ve poured two soups into one big pot and all the flavors will be competing. You may get lucky and see the features of both lines have mixed in a dynamic way towards what you aimed for (a good stew, a dark egg), or you may get unlucky and realize you’ve undone the work of the breeders before you and are starting from square one again (a mush pot of indistinct flavors resulting in basic brown).

Backcrossing is a breeding strategy that does the opposite of outcrossing– it forces out the hidden (recessive) features that one line carries (allowing you to suss them out select away from them) , while condensing or strengthening the traits you are selecting for— in our case dark pigment deposit!

Backcrossed to Marans (pigment deposit)

To be very specific, most of our backcrosses are a backcross to the pigment depositing breed of our olive egger project— Black Copper Marans in our Purple Copper line— for darker olives to bark colors. That means our olive egger hens (who carry blue egg shell genes from their Legbar or Ameraucana lineage *and* have pigment depositing abilities because of their Marans lineage) are crossed back under their father Marans (our Purple Coppers) to further condense their pigment depositing genetics. This darkens their olive color along the spectrum and sometimes results in speckled eggs and heavy bloom eggs that look gray.

Backcrossed to Ameraucana (blue egg shell)

Eventually, backcrossing results in a loss of the blue egg shell gene, because Marans carry zero copies of the blue egg shell gene and males will pass a white egg shell gene in each breeding. When your female offspring loose both copies of the gene that makes the egg shell blue, you no longer have an olive egg, just a white egg shell with lots of dark pigment on top (in shades of bark, pinecone, coffee— with much depending upon the undertone of your Marans pigment). At this point you can take your very dark olive egger or coffee-bark layer and backcross them to their blue egg shell genetic parentage— putting your dark olives back under blue!

Theoretically, if your blue egg shell male is homozygous and carries two copies of the blue egg shell gene (as a good line of Ameraucana should!), this will regenerate the blue egg shell underneath the pigment in your next generation, ensuring an olive egg.

So, the only way to ‘stabilize’ backcrossed Olive Eggers is to have a plan for how they get coded for heavy pigment deposit AND blue egg shell genes in successive iterations. In our opinion, olive egger hens that carry two copies of the blue egg shell gene AND have multigenerational tendencies to deposit lots of pigment lay the most dynamic eggs.

Egg Color Tendencies

Crosshatch Farm Backcrossed Olives tend to deepen the olive egg color to a rich olive to bark pigmentation, or can sometimes result in a mauve, gray or even a rare mustard egger if under a heavy bloom. Our olive egger layers lay a spectrum of maybe five varying shades of green— all of them are backcrossed to Marans this year.

Plumage

Backcrossed olive egger chicks can look very similar to their pure-bred Black Copper Marans lineage, especially by their third or fourth iteration, so you’ll want to be careful to not mix them up.

Plumage is often predominately black with copper features— copper necks to full copper pencilling across the breast. Occasionally they can be blue-based, with blue bodies and copper features. We will have some paint offspring in 2025, but these will be in our backcrossed to blue offering (dark olive eggers under an Ermine Ameraucana which injects dominant white and can result in paint plumage).

Birds displaying muffs and beards show their Ameraucana lineage. Birds displaying crests show their Legbar heritage. Some of our backcrossed olive eggers will have both!