The “Tiger” morph of the Coastal Carpet Python (Morelia spilota mcdowelli) was established in California by Neville James back in the late 90’s from animals he acquired from Richard Quick in Alaska. This morph is characterized by a nearly unbroken, wide dorsal stripe and lateral striping that can be either unbroken or in a uniform oval/dash pattern. It is also characterized by a very defined solid black head pattern with one or more light blotches within the center of the head and a connecting neck stripe that descends the dorsal portion of the neck. These animals have light yellow to manila dorsal striping with a chestnut to dark brown background color.
This morph was once believed to be a co-dominant mode of inheritance with speculations of a possible “super” form, but subsequent pairings have shown that it is a polygenic trait that relies on pairing a Tiger with another carpet that has similar genetics. This allows the Tiger gene to better present itself in the offspring. I have found that breeding two visible Tigers together produces a clutch that yields 100% Tigers. Whereas, breeding a Tiger to a non-Tiger parent produces offspring where the clutch is, on average, half normally patterned and half that are partially to fully striped. The offspring from the original pairings were so dark when first hatched, that the striping was barely discernable. However, after the first shed the stripes were clearly visible and lightened up after each subsequent shed cycle.
I received my two original Tigers directly from Neville James back in circa 1997. I raised them, bred them together, and produced a clutch of all Tigers. The following year, in 2003, I sent my female to my partner to breed to his Jaguar. Only three viable eggs were produced and yielded the first Tiger Jaguar. This animal had a noticeably reduced pattern than any of the Jaguars that were being produced at that time. It was clearly displaying traits from both parents, including an interesting copper color in the ovals. These pairings went on to produce some amazing animals over the years which still serve as the foundation of many of my breeding projects that still exist today.
As noted previously, the Tiger gene also pairs well with other Carpet morphs. When bred with a Jaguar morph, the Tiger gene opens the Jag pattern even more and, in some cases, produces animals with a highly reduced pattern. Crossing it into the Axanthic, Red, Caramel, and Hypomelanistic genes has also yielded some quite remarkable offspring as well. I am particularly looking forward to a couple of clutches that have been produced this year where Eric Koller, Kyle Harper and myself, entered into a breeding arrangement where we bred Kyle’s Hypomelanistic Coastal to one of my Tiger females and a Het Axanthic Coastal from Eric. The offspring produced from this Tiger pairing should yield some really interesting examples of how the Tiger gene influences the Hypo gene and vice versa. To my knowledge, this will be the first pairing of these two Coastal morphs in the states (Paul Harris has done this pairing in the UK using animals he received from me). The female Tiger used is one of the best examples of the Tiger Coastal Carpet morph and the offspring from this clutch should be heavily striped with some amazing color.
It is also relevant to note, the majority of the Tigers in the hobby today originated from one pair of animals. Although many were produced and bred back together in order to confirm their genetic inheritance and to refine the pattern of the offspring, outcrossing was necessary to maintain a viable gene pool. It is interesting, and more so gratifying, to see that the majority of these pairings with other Carpets outside of this line has not diminished the overall presentation of this gene. Thanks to selective breeding, the overall appearance of the striping, head pattern, and other traits that were unique to the original animals from this line are present in animals that are being produced today.
The Tiger gene has been a staple in the hobby for quite some time now, but continues to remain relevant due its predictable mode of inheritance and its ability to pair well with other pattern and color morphs. As new morphs emerge and others get refined, it’s a good bet the Tiger gene will be around to compliment them. I have thoroughly enjoyed working with this gene/morph and it will always be the cornerstone of my Carpet collection. I can’t wait to see what more we can do with them in the future.
