The snake-slayer with lightning reflexes

When Covid had the world in a bind, we spent extended periods of time at Navilu Kaadu. So did our caretaker’s goats, every time we left for Bengaluru, as we discovered much later!

When we got wind of the intrusion, we set about finding proof. We browsed through the archives of CCTV footage (that we had neglected to monitor) and watched in dismay as the goats chomped, tore, tugged at and stripped our plants bare all day long.

At twilight, the goats tamely followed our errant caretaker, swinging bellies distended from an entire day’s gorging, as he led his menagerie back to their hold in the village. This flagrant trespassing ended up altering Navilu Kaadu permanently. The turd from the interloping goats introduced seeds of a dreaded invasive into the land — Subabul or river tamarind (Leucaena leucocephala), notorious for edging out native species, which has since become our worst nightmare as we try to restore biodiversity on Navilu Kaadu.

Even as we watched the goat horror show, we stumbled upon something unexpected and exciting — our cameras had captured a wild mammal taking a stroll by our porch — an Indian grey mongoose (Herpestes edwardsii).
With around six-odd snake species inhabiting our wild grassland, can their nemesis be far behind?

While the rest of the animal kingdom treads cautiously around venomous snakes, mongooses rarely miss a chance to pick fights with and inflict skull-crushing bites on the deadliest of serpents.

Are they immune to snake venom? Or are mongooses just agile and able to dodge snake strikes effortlessly?

Remarkable physiological adaptations and lightning-quick reflexes make mongooses formidable serpent predators. Let’s decode the biology behind their seeming inviolability against snake venom.

Mongooses aren’t immune to the venoms of all species of snakes, but they can stave off the lethal consequences of neurotoxic venom from snakes of the Elapidae family, such as cobras and kraits, to an extent.

In the normal course, the neurotoxins in the venom of Elapid snakes target proteins called acetylcholine receptors that transmit signals between nerve cells to aid muscle action. The neurotoxins bind these protein receptors, jamming nerve signals, which in turn triggers fatal paralysis. In mongooses, the acetylcholine receptors have evolved to prevent the neurotoxins from binding to them, weakening the effect of the venom on muscle cells. This adaptation is less effective against viper venoms, which are cytotoxic and hemotoxic and cause tissue damage and internal bleeding.

Even with the adaptation, a large dose of lethal venom delivered with precision can prove fatal to any valiant mongoose.

The Haavu-Mungusi (snake-mongoose) rivalry has been the stuff of legend for aeons. As a little girl, I teared up watching the brilliantly picturised song, an apologue of sorts, ‘Keliddu Sullaagabahudu…’ from the Kannada flick Rama Lakshmana about a pet mongoose guarding an infant. The alert mongoose takes down a spectacled cobra as it slithers too close to the baby’s cradle. In what turns out to be a case of mistaken identity, the heroic mongoose tragically ends up paying for the good turn, with its life.

There are other fables too, the most famous being Rikki-Tikki-Tavi by Rudyard Kipling about an English family’s pet mongoose, which foils the insidious plans of a pair of cobras to wipe out the human family. I have a bone to pick, though, about snakes being vilified in film and fiction as scheming, vengeful creatures, for merely acting in self-defense. That’s a story for another day.

The 19th-century British naturalist Robert Armitage Sterndale writes with affection about ‘Pips,’ his pet mongoose, in his book ‘Natural History of the Mammalia of India and Ceylon,’ observing that domesticated mongooses could show as much attachment as a dog.

From the tales and the memoir, it appears mongooses were popular household pets back in the day, not least for their snake-catching qualities.

Indian grey mongooses are native to the Indian subcontinent. They don coarse grey fur and are diurnal mammals that forage and hunt during the day. While they relish snakes, mongooses also enjoy an eclectic diet of tubers, berries, fruits, frogs, grasshoppers, lizards, insects, birds, scorpions and fish.
These plucky snake slayers are poached for their fur to make paint brushes. Is there anything that avaricious humans don’t hanker after…

Rooting For Nature is a monthly column on an off-kilter urban family’s trysts with nature on a natural farm. The author runs Green Goobé, a sustainable venture. Reach her at [e-mail] or @ramyacoushik on Instagram.