SIZE MATTERS!

Published in Sanctuary Asia Vol XXVI No. 6, Dec 2006

Kalia was a woman-eater. He was estimated to be a 23 to 24 foot (7.01 to 7.32 m.) salt-water crocodile who ruled a 10 mile (16.66 km.) stretch of the Dhamra River in Bhitarkanika, Orissa. The then Raja of Kanika wrote in 1973 that this unusually dark skinned reptile eluded shikaris including his grandfather and father for 50 years. In 1926, the captain of a ship on a run from Chandbali to Calcutta eventually shot it. The injured reptile crawled onto the bank taking shelter in the reeds and tall dry grass. Seizing the opportunity, the villagers set fire to the vegetation killing the croc.

For several years, Kalia’s skull welcomed visitors to the palace in Rajkanika while the bangles and anklets found in his belly were displayed on a table, gruesome reminders of a horrific period in the region’s history. J.C. Daniel and S.A. Hussain of the Bombay Natural History Society were the first to measure the salt-water crocodile’s skull in 1973 and reported that it was the largest skull in the world at 100 cm.

Robert Bustard and Romulus Whitaker wanted an accurate figure and in 1974 they went up to Bhitarkanika to measure the skull. It was hanging way up on the wall out of reach and it wasn’t a simple job getting it down. So using a stick they came up with 98 cm. Years later, Rom realized that they had made a mistake. Instead of measuring the skull from snout tip to the occiput (back of the head of the upper jaw), they had measured it all the way to the back of the lower jaw, a mistake that several people continue to make thus confusing the issue of crocodile morphology.

If you are wondering why the measurement of the skull has to be so specific, it’s because crocodile biologists use it to extrapolate croc sizes. The length of the skull (measured along the median line from the tip of the snout to the back of the occiput) is multiplied by seven to arrive at the animal’s total length. Scientists came up with this equation after measuring hundreds of alligators in the United States and rapidly biologists around the world began using it to estimate the lengths of several species of crocodiles.

Although there have been several reports of bigger crocodiles being shot in Australia – one was estimated to be 27 ft. (8.23 m.) – there is not a shred of evidence (skull, skin or photograph) to prove the hunters’ claims. In the 19^th century, a monstrous 33 ft. (10.06 m.) croc was reportedly shot in Bengal and the skull lodged at the British Museum of Natural History. When the skull was measured it was only 60 cm. long and a simple arithmetic puts the animal at 13.78 ft. (4.20 m.).

For a couple of decades Rom tried unsuccessfully to access Kalia’s skull and in recent years began to fret that it might have disintegrated. Through Aurodam David in Auroville, we finally met Shivendra Bhanjdeo, the Yuvaraj of Kanika. He confirmed Rom’s worries – the skull was indeed falling apart and he wanted assistance in preserving it. Rom, in turn, sought the help of Dr. Russ McCarty, paleontologist at the Florida State Museum in Gainesville, who is a professional preserver of bones. He recommended a substance called Butvar (polyvinyl butyral). It wasn’t available in India, so friends kindly brought over a pound of the white crystals.

Earlier this year, we went up to Bhubaneshwar where the skull had since been moved from Rajkanika. It wasn’t in as bad a shape as we feared – the sutures holding the various parts of the skull were still intact. A slice of the upper jaw was missing (as it was even in the 1973 photograph); the captain must have shot the animal through the body. The skull had to be cleaned thoroughly and an enterprising businessman friend, Vinny took on the dirty work – alternately brushing and pumping jets of air with a bicycle pump, he managed to get most of the grit out. It was impossible to reach the crevices and the tooth sockets, so he hauled it off to the local tyre puncture fixer. It was only because Vinny was barking orders that the bewildered mechanics did what was needed. After being air-blasted, the skull returned looking several shades whiter. The Butvar had to be dissolved in acetone (without forming lumps, just like good gravy) and the thick glue brushed on the skull. An iron tub (plastic melts when it comes in contact with acetone) of adequate size was found and with the heavy skull levered by a long bamboo pole, the Butvar was poured over it. The preservative soaked into all the cracks, crevices and pores virtually encasing it and now the skull is good to last another 100 years and probably a lot more.

Finally, the moment Rom had been waiting for 30 years arrived. The tip of the snout to the occiput measured only 73.3 cm. We added three centimetres for the four per cent shrinkage when the skull dried out, and checked and double-checked the measurements. There is no doubt about it, by using the standard ratio for crocodile head length to total body length, Kalia would have measured 17.52 ft. (5.34 m.), significantly short of the 23-24 footer that it was claimed to be.

Some experts however, have expressed doubt if the 1:7 ratio can be applied universally. While the ratio is consistent in alligators, it varied wildly in crocodiles. In 1979, while Rom was doing a crocodile survey in Papua New Guinea, tribal hunters proudly showed him the skin of a crocodile that measured 20.34 ft. (6.2 m.). The fresh skull was 72 cm. long making it a 1:8.6 ratio. The behemoth had drowned in a tiny barramundi net.

In another instance, Australian croc biologist Grahame Webb measured a salt-water croc skull at 66.6 cm. belonging to a freshly killed 20.18 ft. (6.15 m.) animal. This ratio of 1:9.23 made Kalia a whopping 23.11 ft. (7.04 m.), closer to the Raja of Kanika’s claims. As a final test, we measured the closest giant at hand, Jaws III, at the Madras Crocodile Bank. The ratio was 1:9. The emerging theory is that young crocodiles may follow the 1:7 ratio, but as they grow older, the skull doesn’t keep up with the rest of the body, until at 35+ years of age they reach 1:9. If we could estimate these growth changes, it would be relatively simple to estimate the age of crocs.

Recently, we traced the skull of a false gharial from Borneo to the Munich Museum. It measured 81 cm. (snout tip to occiput). So the current record holder for the largest crocodilian skull in the world is not a salt-water crocodile (the traditional favourite) but an endangered long-snouted fresh-water reptile. It seems likely that none of these ratios would apply to gharials and false gharials so we can only speculate what length the Bornean false gharial reached.

Among crocodiles however, the largest skull, measuring 76 cm, belonged to a salt-water crocodile from Cambodia, now at the Paris Museum. The second largest skull (73.5 cm) is of an American crocodile at the American Museum of Natural History, New York and the Kanika skull ranks third in the world. There may yet be other larger skulls collecting dust in private collections but until they are measured, all stories of humungous crocodiles remain in the realm of old hunters’ tales.

The crocodile census conducted in Bhitarkanika in January indicated the presence of a 23 ft. (7.01 m.) crocodile (would we love to put a tape measure on that beast!!). Given the high degree of protection the Crocodile Sanctuary enjoys from the Orissa Forest Department (and the salt-water crocodiles themselves), it seems that this is one of the few places on the planet where these giant crocodiles will continue to rule into the 22^nd century.

Crocs of the tidal zone

Published as a chapter in Sundarbans Inheritance, Sanctuary Books, 2007

Narrated by Rom Whitaker; written by Janaki Lenin

Abdul Aziz Mulla, a honey collector, stumbled upon a saltwater crocodile nest just as the eggs were hatching. Since he couldn't see the female anywhere close by, he picked up a baby croc, which immediately started squawking in alarm as baby crocs will do. The mother, which had slipped into a muddy wallow on his approach, heard its baby's call and swung into defensive action, erupting from hiding to grab his leg. He threw the baby croc at her, which is all she really wanted. A few bad scars later, even Abdul admitted she wasn't a man-eater. Surprisingly, this was just one of the few croc attack accounts I heard in the Bangladesh Sundarbans about 25 years ago.

I spent three weeks in the mangrove forest aboard the 10-metre-long District Forest Officer's launch, Bana Sundri in 1981. With its six-man crew we conducted perhaps the first crocodile survey undertaken in the Sundarbans. The swamp was always notorious for its man-eating tigers and we had a 24-hour armed escort; while I appreciated the necessity, I soon began to chaff at the lack of privacy. Celebrity-hood was never my bag!

The best place to start my study was by interviewing the people who lived on the edges of the crocodile swamps. Interestingly, apart from their myths and legends, few really knew about crocodile natural history or behaviour. Many actually confused the nests of wild pigs and crocs, and I found myself personally checking each nest they thought they had located. This involved crawling on hands and knees through thorny Phoenix palms and 1.5 m. tall tiger ferns, not named for its feline looks but because its dense stands are a favoured hide-out for tigers.

Visibility at such times was about as far as my nose. Elsewhere humans are usually the hunters -- the kings of the forest. In the Sundarbans the tables are turned. You feel hunted; just prey. Understandably, we constantly looked over our shoulders, listening for every small sound and, I am not ashamed of admitting, quaking in our shoes. It was the poor visibility combined with constant reminders from everyone I met that made walking in the tiger's turf as heart-pounding as running a marathon at high altitude. Yes, the armed guard was always behind me with his ancient and cumbersome Enfield .303 cocked. But that itself was a creepy feeling. Would I end up as tiger fodder, or would a jumpy guard armed with an unpredictable rifle accidentally get me?

Walking in the mangroves is a seriously tough business. I was often knee deep in mud in some places, thigh-deep in others. If a tiger did actually turn up running was never going to be an option. The big cat had the advantage of enormous snowshoe-like paws, but the aerial roots, the pneumatophores, of some mangrove trees would be an impediment even for the cat. My feet slipped and slid sideways as I tried to step between the sharp spear-like roots, straining muscles unused to this strange manner of walking. Meanwhile, monkeys jumped artfully from pneumatophore to pneumatophore and deer raced through them faster than a tiger possibly could. Any two-legged human treading this swamp was at a major disadvantage.

Once you are out of the tiger’s turf, you walk straight into bull shark waters. The first time I returned after a walk in the mangroves, I recall trying to wash the black gooey mud off my legs in the river before getting on the launch and was chastised for my trouble. In the boat crew’s view my white legs were ideal shark bait so I was ordered to always hop up on the launch first, scoop up a bucket of water from the river and only then wash my legs… away from of jaws of water-borne predators.

When the tiger does not make it into their conversation, people who visit the Sundarbans talk of crocodile attacks. It’s more hype than fact. Though that might have been true in the old days when crocs were common, 25 years ago I found no evidence to support the stories. Also there was confusion about whether people had been attacked by sharks or crocs. None of the scars from the injuries I physically examined were caused by crocodiles and six or seven victims down the line I was inclined to think that the so-called croc attacks was the work of sharks. People sifting for shrimp seedling were especially at risk because bull sharks commonly hunt in muddy waters along the shore. Some are maimed by relatively small sharks, about 1.5 or 1.8 m. long, which would grab a leg or an arm and shake vigorously tearing off skin, flesh, part of an arm, or a leg. As for the crocs, I just never saw enough of them. Nor it would appear do most land animals because deer, wild boar and tigers seemed to have no qualms about swimming across creeks, streams and rivers as evidenced by the many pugmarks and hoof prints visible on the edges of muddy banks.

When darkness fell, I would stop conversing with humans and begin working on what I loved best – looking for crocs. I used a powerful spotlight that made crocs’ eyes shine, giving them away. High tide was never any good to me as the reptiles would be deep in the mangroves. I found myself gliding along the waterways using the same methods that croc hunters once did, to devastating effect, in the 1950s when the skin industry was at its peak. Three decades later the few surviving crocs in the Sundarbans were still wary of humans.

Days passed. And despite scouring ideal croc habitat night afternight, frustration began to set in. The only crocs I was able to spot were hatchlings or yearlings. Though I followed up on local advice: “Go downriver to such and such place and you will see them basking” all I ever saw were a few slide marks. Then, out of the blue (brown actually!) one day, I saw the broad back of a monster croc – an 18 footer (5.5 m.) -- swimming languidly out in the middle of the Bhola River. I am unlikely to forget that sighting because it was one of the precious few crocs I ever saw in the Sundarbans. Ultimately after covering over 433 km. of mangrove creeks and rivers in three weeks, I counted just six, and saw evidence of six more during that survey. That’s a density of 0.028 crocs per km.

Drifting along the mud-lined and mangrove clothed waterways of the Sundarbans, watching the forest go by day after day can get monotonous so I would entertain myself fishing. Occasionally we would stop at a forest rest house and I would go out looking for snakes to take my mind off the survey that was not working out quite as I had hoped. When I go snake hunting, I don’t like people around; I like to concentrate on what I’m doing. But since the forest was ‘dangerous’ I could not casually wander off on my own. One afternoon while the guard was catching some shut eye post-lunch I sneaked off to look for snakes around the dighi, a freshwater pond away from the main river. I found some interesting water snakes and was totally engrossed when I suddenly heard shouting -- the guard was running towards me with his rifle ready. I quickly looked around to see if I was about to be pounced on by Dakshin Ray, the tiger god. The guard was angry: “If you get eaten by a tiger, they will blame me.” And I responded: “Yeah, but I’m right here. The rest house is in plain sight.” It was then that he narrated the hair-raising story of a Forester who had been taken by a tiger right in that dighi months earlier.

My survey was not particularly exciting in terms of snakes either. Cruising along one of the meandering mangrove rivers in a launch one day I saw a largish snake swimming across at speed and I scooped it up with a landing net. The boat crew was horrified that I had dumped a monocled cobra on the deck. As it sat hissing and dramatically displaying, the six crew members stood nervously as far back as the boat would allow, causing it to rock precariously. “Throw it back. Throw it back,” they yelled in unison and I replied in my best American-Bengali accent, “Nai… nai… nai. I want to take it to the shore and take pictures.”

My will prevailed and as they took me ashore I jumped into the mud. It was tricky – I had a camera around my neck, a cobra in one hand, a stick in the other, and was stuck up to my knees in mud. I did manage to get pictures, however, and this made an impression on the boat crew who talked about it all the way back. They then told me about the king cobra that climbed up the anchor rope of the launch that they “somehow beat off” before it could crawl aboard.

That night while the boat lay anchored in the middle of the river, I heard many tales of tigers with superhuman talents. Like ghost stories, everyone in the Sundarbans has his own tiger tale. The boatman narrated particularly extraordinary stories of tigers stealthily climbing aboard anchored fishing boats in the middle of the river and making off with adult men without waking anyone else. For effect he informed me that tigers make people lose not only their voice, but drains energy from their limbs so they cannot run. In a philosophic aside, he quoted the motto of the Sundarbans “Jale kumir, dangai bagh” -- crocs in the water, tigers on land.

If merely floating midstream could cause so much fear, I can only imagine what they thought about crawling through the mangrove slush. The armed guard walking with me in the thick bush was a psychological prop, but the benefit of doubt would have to be given to a determined tiger against the old bolt action .303 of the shaky guard. Nevertheless, even I was grateful for company as this halved the odds of a tiger attacking me! (Besides, a gun going off with a bang would probably scare any sane cat away.) Nobody went into the Sundarbans alone, whether fishermen, wood cutters or honey collectors. The bigger the group, the lower the risk. People sought safety in numbers for the same reason fish schooled together. I found myself inwardly happy that there was a part of the planet where humans were forced to think and behave like prey animals. Early man must have felt the same fear when sabre-toothed cats prowled around his campsites.

These people whose lives were governed by the tides lived in a fantastic world of terror and mythology embroidered with fact. I just could not tell what was real and what was not. A group of honey collectors spoke, as expected, about crocs and man-eating tigers and surprisingly, a few people who “got away.” One might imagine that if a tiger got a hold of you that was where the story would end. But in one case a charismatic honey collector spoke of a tiger that made the mistake of catching a man by the leg rather than his neck and began dragging him away, still alive. When the man realised that he was bouncing around between the hind legs of the tiger, he is said to have reached up to bite hard on the tigers’ testicles until it let him go. This was probably the only tiger attack story in the world that made everyone roll on the floor with laughter. There were other cases of people who actually fought tigers with their axes or machetes. And one man in the group philosophically concluded that “people are eaten by tigers because they torture the forest.”

What really scared the daylights out of me about the Sundarbans was not being attacked by an animal; it was being caught in a storm while paddling a canoe. I was there in April, the pre-monsoon storm season. If we were surveying by canoe at night, we ventured out only after carefully reading the skies for signs of an impending storm. One night, we misread the signs and got caught by the weather gods in Bainkari Khal. The chop of the waves even in that little creek was so bad that the canoe was swamped within minutes. Sharks and tigers were the last things on our minds when we jumped into the mud to haul the canoe up out of the water. The craft was our lifeline and the strong current kept trying to pull it away from us until we managed to tie it to some mangrove roots. We were covered in mud from head to toe and the strong wind against our damp clothes chilled us to the bone. Shivering, we crouched in the donghy, retying it periodically as the tide came in. For an hour and a half the wind tore through the forest shaking down sticks and leaves and sending them flying around like dangerous confetti. Lightning struck all around us and we just hung on for dear life. During this season, a lot of boats get lost and people lose their lives.

In the aftermath people remembered a super storm that hit in 1978-1979. The tidal surge had been between six and nine metres high, and people had to climb fast to stay above it to survive. Fortunately, because of the optimum salinity, mangroves species grow to over 15 m. tall in the swamp forests of Bangladesh. Along with the clinging humans, tigers, wild boar and even deer had been seen on trees together with the snakes and other creatures. When the storm subsided, 200,000 people and as many animals lay dead among the mangrove roots.

Mangroves are one of the most vital buffers against super storms anywhere in the world as we recently discovered when the huge tsunami hit Asia. No other place in the world attracts as many devastating storms as the Sundarbans does. If you trace the paths of a hundred cyclonic storms spawned in the Bay of Bengal, about 90 of them hit the Sundarbans. Without the mangroves to absorb the fury of the elements, a tidal surge up the Meghna River would flatten many villages and towns in its path.

Despite this critical function, the Sundarbans has been systematically whittled down to roughly half its original extent. For centuries, mangrove wood was extracted for construction of piers and jetties because they are naturally resistant to damage by saltwater. Much continues to be burned as firewood. When there were working plans for timber extraction, one tree specie was particularly discriminated against – the baen or Avicennia officinalis. These big, mature trees rot at the base creating big holes where tigresses are able to deposit their litters, pythons their eggs, and where a host of creatures such as civets, mongooses and monitor lizards can find a home. These old, rotten trees were useless as timber and were the ones removed for firewood.

I was told of a female python that was found incubating her eggs in one such tree hole. It was promptly killed and her four metre long skin hung in the launch that was my home in the Sundarbans. It was one of the biggest Indian python skins I had ever seen. As if to confirm the story, I discovered a shed python skin in one such huge tree hollow.

Many years later when I returned to the Indian Sundarbans in 2003, my spotlight survey was just as fruitless, though we did see a few more small crocs. It was the same old story. In contrast, in 2006 I counted 65 saltwater crocodiles in Bhitarkanika in an hour’s cruise. So why were there so many in Orissa? It has to be because pro-active conservation helped the crocodile make a remarkable recovery. The number of crocs of all sizes in Bhitarkanika, a comparatively small 672 sq. km. forest, is around 1,500. That’s a density of 10 crocs per km. Yet in the 10,000 sq. km. of the Sundarbans, which ought to have many times more crocs, reportedly supports only a miniscule population.

I am puzzled by the appallingly slow recovery of the saltwater crocodile in the Sundarbans (both sides of the border) despite nearly three decades of protection. Could lack of ideal nesting sites be the reason? Croc nests are not only obvious mounds; the females also draw attention to them by creating visible tracks. So it is vital to have undisturbed nesting areas with little or no human interference. In the years past, people collected eggs opportunistically to eat, but only two active nests had been found in recent years. Once croc exploitation reaches a certain threshold, their chance of recovery hits a point of no return unless the nest sites are vigorously protected.

Like crocodiles, monitor lizards too have been hammered by the skin industry. People camped in large parties on the edge of the Sundarbans and used dogs to corner and kill monitors with ruthless efficiency. So, even though the habitat was intact the numbers of these lizards seemed pitifully low. Someone should investigate what is preventing them from recovering.

The river terrapin, Batagur, is another reptile in trouble. The mangrove swamps once abounded with these huge turtles that were hunted for meat with baited hooks. The method was simple, a rope was strung across a fairly large river with hundreds of hooks and each hook was baited with the little yellow mangrove fruit of Sonneratia apetala that turtles love. My crew demonstrated how they used to catch them years ago, but all they could show me were the half a dozen captive terrapins being reared in village ponds.Today, the turtle is more or less extinct with small chance of recovery.

To understand what happened to the Sundarbans in the early days of human colonisation I looked at the Andamans where some of the pioneering human settlers of the smaller mangrove ecosystem were Bangladeshi refugees. The first thing they did was to clear the area, where the freshwater meets the saltwater, of all vegetation – mangrove trees, Nypa palms, Phoenix palms, the lot. Apparently, this is the best rice growing zone. This is also prime croc nesting habitat. In the Sundarbans, when the monsoon combines with high tide, storm surges sweep up through the mangroves drowning croc nests. The only place where croc nests will not be inundated is the non-tidal rice growing area.

What really drove this poignantly home to me was finding the bones of a female croc still on top of the remains of an old nest on the edge of the Sundarbans that had been freshly cleared for rice planting. She had been killed while guarding her nest. Ironically it was her maternal protective instinct that sealed her fate as she could easily have swum away from her tormentors. This epitomises how crocs were wiped out. The first wave of hunters killed the animals for their skins, the second wave of egg collectors robbed nests and the final nail in the coffin was the loss of prime nesting habitat.

The only available habitat left for crocs in the Sundarbans now is the tidal zone and although babies were successfully hatching in some years, they need freshwater to drink. During the rains they survive on rainwater, but after this when the rivers slow down to a trickle and saltwater flows in from the sea, baby crocs do not have a hope in hell of surviving. Which meant the yearlings I was seeing on my night surveys were probably a doomed lot.

Besides habitat, the other important factor is the prey base. Fish is a primary food source for crocs, monitors, and turtles, so I checked on the fishing trends. The high shark population inhibited fishermen from getting into the water to drive fish, so some used tame otters to do their job for them. Once the net was set up the otters corralled the fish along the shoreline. The mullet jumped through the air in panic and some actually leaped onto the shore and lay flapping in the mud. But most fishing is still done with traditional nets and the size of the mesh is one standard method of estimating resource exploitation. Typically people started out with nets of five to eight centimetre mesh size. Then gradually the mesh size got smaller, and now they use what can only be described as mosquito nets to pick up even the tiniest fish. Of all the other pressures stacked up against the aquatic reptiles, this is perhaps the main whammy – the bottom of the food chain is collapsing.

We had gone to the Sundarbans expecting to see crocodiles rule the tidal forest but came away instead with the realisation that despite the vastness of the mangroves, these animals had been systematically wiped out.

There can be no one silver bullet recommendation to set things right. The deep malaise afflicting the Sundarbans needs systematic long-term research, coupled with instant, effective conservation action. For a start, a comprehensive survey is needed to pinpoint nest sites for focused protection. I was thinking about this when a loud thump jolted the boat and almost knocked us overboard. The propeller had hit a submerged log and the blade had broken. The choking exhaust fumes caught us fully in the face as the boat sputtered into silence. Until the propeller was fixed we stewed in our sweat as we drifted downriver watching macaques picking the debris left by the receding tide.