A large red-bellied black snake (Pseudechis porphyriacus) turns its head to acknowledge me as it makes its way around a shallow swamp. I had been waiting to encounter a red-bellied black for quite a while. Despite this species being one of the most common snakes in southeastern Australia, I had only seen a glimpse of one near Canberra. Before coming to Australia the alluring deep black and red color pattern had caught my eye, much like the electric yellow and black tiger rat snake (Spilotes pullatus) in Central America — another snake that eluded me for months.
Red-bellied black snakes belong to an iconic genus of Australian elapids, a group that includes the King Brown / mulga snake (Pseudechis australis). Red-bellies are associated with wetlands, swamps, and small-bodies of water, and they are pretty much as semi-aquatic as elapids get, other than the sea snakes. Curiously, the red-bellied black is the only snake of the genus to give live birth (ovoviviparous). The entire black snake genus is well-known for its medical significance. However, they have a calm disposition in comparison to brown snakes (Pseudonaja spp.) which may readily employ their defensive display. The display involves rearing up to show a spotted belly accompanied by gaping and hissing. This behavior often leads people to believe the snake is aggressive, but it’s really only a means by which to deter predators from attacking the snake. For humans there is no risk of injury as long as you just walk away. Red-bellies also have a deimatic display, but generally only initiate the behavior if directly confronted or restrained. Scroll down to see some photos of flattening of the body and hooding, reminiscent of a cobra.
Black snakes are more heavy-bodied than the browns and give you an impression of their heavy presence, slowly tongue-flicking and freezing before continuing along their way. Sort of a “I’m here and don’t mess with me” attitude in contrast to a fight or flight response in brown snakes. Many people who get envenomated by red bellies report anosmia, the inability to taste and smell, for up to a year. I’ve heard several accounts of this personally. Lots of interesting properties in venom compounds to be investigated!
Red-bellied black snake photographed after disturbance  unless otherwise stated
Photos below of Spilotes pullatus, the species that long eluded me in Costa Rica; photographed after capture