Baja California Coachwhip, Coluber fuliginosus 

Baja California Coachwhip, Coluber fuliginosus, Light Phase. Snake collected as road-kill on Mex 1, Santiago, Baja California Sur, May 2018. Length: 1.07 meters (3 feet 6 inches). Identification reconfirmed by Gary Nafis, Californiaherps.com.

Baja California Coachwhip, Coluber fuliginosus, Light Phase. Snake collected as road-kill photographed of road-kill on Mex 1, east of Las Cuevas, Baja California Sur, July 2021. Length: 1.52 meters (5 feet 0 inches). Identification courtesy of Gary Nafis, Californiaherps.com.

Baja California Coachwhip, Coluber fuliginosus, Dark Phase. Snake photographed in the bush of the greater Bahía Santa Rosalillita area, Baja California, September 2015. Photograph courtesy of Barry Mastro, Escondido, California. Identification courtesy of Gary Nafis, Californiaherps.com.

The Baja California Coachwhip, Coluber fuliginosus, is a member of the Colubridae family of North American Racers, Coachwhips and Whipsnakes. The Colubridae family comprises two-thirds of the world’s snake population with one thousand seven hundred sixty species placed in two hundred forty-nine genera. There are eleven species in the Coluber genus. Many Colubrids are classified as venomous but very few are considered to be dangerous to humans. Baja California Coachwhips are named for their braided appearance created by the scales on their tail. The Baja California Coachwhip is known in Mexico as Culebra Chirrionera de Baja California. 

The Baja California Coachwhip is a slender and fast-moving snake with smooth scales, a large head and eyes, a thin neck, and a long thin tail. They have large scales above the eyes and 17 rows of midbody scales. They have two color phases, a dark phase and a light phase. The dark phase is dark brown or dark gray to black dorsally. Light edges on the dark scales give the appearance of light lines on the sides that are more prominent toward the front of the body. The light phase is a dark to pale yellow, tan, or light gray dorsally with dark zigzag crossbands on the body, wider dark bands on the neck, and spotting on the underside of the head. Only the dark phase has been found in California. They reach a maximum length of 1.52 m (5 feet 0 inches). The average lifespan of a Coachwhip is approximately thirteen years in the wild and twenty years in captivity.

The Baja California Coachwhip is diurnal and usually active mid-morning and late afternoon from March through October. They are primarily terrestrial but will occasionally scale bushes and trees to seek prey and shelter. They hunt by slithering with their head held high above the ground, occasionally moving it side to side to aid in vision and depth perception. Moving at speeds up to 12.8 km (8.0 miles) per hour, they are able to catch many fast-moving lizards. They consume small mammals including amphibians, bats, nestling and adult birds, bird eggs, lizards, snakes, and carrion. The juveniles consume large invertebrates. Their prey is overcome, crushed by their jaws or beneath loops of their body, and then eaten without constriction. They are known to bask on roads in the early morning and consume small road-kill animals so the Baja California Coachwhip is often found as road-kill. They take refuge in the hollow stumps of plants such as agave. They can tolerate high-temperatures and inhabit scrub, coastal sand dunes, rocky arroyos, thorn forests, marshlands and sandy flats.

Mating occurs in April and May, the eggs are laid in June and July, and the first young appear in late August to early September. Reproduction is oviparous and  clutch size ranges from 4 to 16 eggs with an average of 8 to 10. In a lab setting, the incubation time is 76 to 79 days. The Baja California Coachwhip is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.

The Baja California Coachwhip are often confused with other coachwhip snakes but can be differentiated by their color and lack of a well-defined stripe lengthwise on the body. 

From a conservation perspective the Baja California Coachwhip is currently considered to be Endangered and Threatened in the State of California. Within Baja California they are considered to be common, widespread, and abundant. They are threatened by habitat loss, fragmentation and road mortality. They are not considered to be dangerous to humans, as they are non-venomous, but they are known to strike aggressively when threatened or handled.