The red-bellied black snake (Pseudechis porphyriacus) is a common sight along Australia’s east coast. While these snakes are frequently encountered, many questions remain about their behavior, including whether Do Black Snakes Travel In Pairs. This article delves into the life history of these fascinating reptiles, exploring their mating habits, social interactions, and other aspects of their behavior to shed light on this question.
Mating Rituals and Social Interactions
Red-bellied black snakes primarily court and mate in the spring, from early October to November, although this behavior can begin as early as late winter. Male snakes actively search for receptive females, engaging in combat with rival males they encounter. These fights involve the males spreading their necks, rearing up, and attempting to subdue their opponent by twisting their necks around each other. The objective is to push and hold the opponent down. These bouts can last from a few minutes to up to half an hour in the wild and can even extend intermittently over several days in captivity. Interestingly, the snakes can become so engrossed in these battles that they become oblivious to their surroundings. The defeated male eventually leaves the area after a “winner” is determined.
When courting a female, the male approaches and rubs his chin over her body. If the female is receptive, she stretches out to allow the male to align with her. This behavior highlights the competitive nature of males during mating season and suggests that they are more often seen individually searching for mates than traveling in pairs.
Reproductive Behavior and Grouping
Female red-bellied black snakes develop yolking follicles in early spring and are gravid from mid-spring to late summer. Interestingly, gravid females in some areas gather in small groups of up to six individuals towards the end of their pregnancies. These groups share basking spots and nighttime retreats. The reasons for this aggregation are unknown, but it’s speculated that it may offer greater protection against predators. During late pregnancy, females cease feeding and remain close to their retreat. After about four to five months, they give birth to between 5 and 18 live young enclosed in a membranous sac. The young emerge from the sac soon after birth, measuring around 28cm in length. Red-bellied black snakes are unique in the Pseudechis genus for giving birth to live young, providing them with an advantage in cooler climates.
This grouping behavior is specifically observed in pregnant females and does not indicate a general tendency for these snakes to travel in pairs.
Conservation Status and Threats
While still relatively abundant in some areas, the red-bellied black snake’s dependence on riparian and wetland habitats makes it vulnerable to habitat destruction. The introduced cane toad has also heavily impacted their numbers in northern parts of their range, as they are susceptible to the toad’s toxins.
Predators and Parasites
Adult red-bellied black snakes are preyed upon by feral cats and, presumably, other ophidiophages like brown falcons and raptors. Newborn and juvenile snakes face predation from smaller carnivorous birds, other snakes, frogs, and even invertebrates like red-backed spiders. They are also susceptible to various endoparasites, including acanthocephalans, cestodes (tape worms), nematodes (round worms), pentastomids (tongue worms), and trematodes (flukes).
Danger to Humans
Red-bellied black snakes are frequently encountered on the east coast of Australia, resulting in several bites each year. However, they are generally shy and only bite when severely provoked. If approached, they often freeze or try to escape. If unable to escape, they will rear up, spread their neck, hiss, and may make mock strikes. The venom has anticoagulant and myotoxic effects, causing symptoms like bleeding, swelling, nausea, and muscle pain. Despite the number of bites, fatalities are rare, and many victims experience only mild symptoms.
Conclusion: Debunking the Myth of Paired Travel
While red-bellied black snakes may occasionally be observed near each other, particularly during mating season or when gravid females gather, there is no evidence to suggest that do black snakes travel in pairs as a common behavior. They are generally solitary creatures, except for specific periods in their life cycle. Understanding their behavior is crucial for conservation efforts and for promoting coexistence between humans and these fascinating reptiles.
References
- Andrew Churchman et.al. (2010) “Clinical effects of red-bellied black snake (Pseudechis porphyriacus) envenoming and correlation with venom concentrations: Australian Snakebite Project (ASP-11)”, Med. J. Aust., 193 (11): 696-700.
- Cogger, H. (2000) “Reptiles and Amphibians of Australia”, Reed New Holland
- Greer, A.E. (2006) “Encyclopedia of Australian Reptiles : Elapidae”, Australian Museum
- Ehmann, H. (1992) “Encyclopedia of Australian Animals : Reptiles”, Australian Museum, Angus & Robertson
- Mirtshin, P. and Davis, R. (1991) “Dangerous Snakes of Australia”, revised edition, Ure Smith Press
- Shine, R. (1991) “Australian Snakes – A Natural History”, Reed Books Pty Ltd
- Wilson, S. and Swan, G. (2010) “A Complete Guide to Reptiles of Australia”, 3rd edition, Reed New Holland
