What really killed Lolong?

Alas poor Lolong, we hardly knew ye. The largest living crocodile that any of us had ever seen is gone, a mere 18 months after he was caught. It's now been a little while since he died, the initial disappointment has passed, teeth have been gnashed and fingers have been pointed. Still, I'm repeatedly asked about what caused his death. We have the official necropsy results of course, although many of you won't have had the chance to see those. So just what killed the largest crocodile in captivity and could anything have been done to prevent it?

Seeing Lolong was one of those "once in a lifetime" events. He was a glimpse into the past, a time that's probably lost forever when truly massive reptiles lurked in the river. For many, Lolong's size was fearsome yet he was remarkably gentle while he was in captivity. Worryingly so, in fact. Of course, Lolong was accused of having killed and eaten at least two people, leading to his "most wanted" status in the first place. Nobody ever proved that Lolong was responsible for those deaths, although it's certainly quite possible and a reasonable conclusion. Despite this, his impact on the Philippines can be measured by their national response to his death, the mourning for an individual whose species is generally despised so much it is compared unfavourably to the nation's politicians. His iconic status did much to earn crocodiles (of the non-political kind) some respect.

I mentioned above that Lolong seemed remarkably gentle. This shouldn't come as a surprise to anyone familiar with the effects of capturing large crocodiles from the wild. It's a phenomenon called "capture myopathy"; the shock of being caught, poked and prodded, and introduced to a completely new and alien environment is a stressful experience, particularly for an animal as large as Lolong who has been master of his domain for decades. It might seem unusual to think of crocodiles as being susceptible to stress, but they're just like any other vertebrate in that respect and something that anyone who maintains captive crocodiles should be aware of.

Yet despite this, crocodiles can adapt remarkably well to captivity. Think about it. In the wild you need to devote all your time and effort to survival, the fine balance between saving energy and finding food, knowing where the best shelter is, where the best breeding areas are, and defending those resources from other crocodiles. In captivity, it's all presented to you on a platter, often without annoying competitors trying to muscle in. The need to range widely in search of food, shelter, mates and virtually anything else is gone, instead the crocodile can stay in the one place where all its needs are met. Believe it or not, this does sometimes happen in the wild; those rare situations where there's plenty of food and shelter within a very restricted area, and wild crocodiles have been found that essentially remain in the same place for years. Fence or not, there's no reason to leave nirvana. A good captive environment has to provide a similar experience, and many zoos spend millions of dollars ensuring this is the case.

Should Lolong have lived in a multi-million dollar enclosure then? I'm sure it would have helped, but when you see some of the muddy holes that wild crocodiles call home you realise that crocodiles aren't looking for aesthetics that appeal to us, they're looking for shelter and the basic necessities for survival. It may not have looked pretty, but Lolong was provided with those basic necessities. Trouble is, there were some fundamental problems that ultimately led to his demise.

Lolong's necropsy* revealed that he died from congestive heart failure compounded by fungal pneumonia, lipidosis of the liver and kidney failure. Essentially his immune system was compromised, and if there's one thing that will do this it's chronic (ie. long-term) stress. Interestingly, it didn't appear to start out this way. He began eating within a few weeks of being captured, which was remarkably quick for a such a large, wild-caught crocodile subjected to a prolonged capture and a post-capture stomach flush. Eating is always a good sign, it shows that the crocodile is comfortable enough with its new surroundings that it starts to resume normal behaviour. Crocodiles do not eat if they are highly stressed, although I'm referring here to acute (or short-term) stress. Some rare crocodiles have been known to literally starve themselves to death after capture, they never adapt to captivity or recover from the shock of being caught. If you've ever asked yourself "I wonder how scientists know that adult crocodiles can last for nearly two years without food?"... well, now you know.

Of course getting a crocodile to eat isn't necessarily cause to relax, but all the signs pointed to Lolong settling down into his new surroundings and behaving normally. So what happened? The answer seems clear in retrospect, and concerns were indeed raised about this practice well in advance. I'm talking about the regular draining of water from Lolong's enclosure, apparently on a daily basis. This was started, so I was told, to ensure that Lolong always had clean water, but it served another purpose: it ensured that the hundreds of visitors who travelled from around the Philippines (and indeed from around the world) could get a clear view of Lolong sitting in shallow water. It would be disappointing to visit the world-famous Lolong and find that he spent nearly all of his time hiding underwater. Indeed, have you ever seen a photograph or YouTube video of Lolong when he wasn't fully exposed? Unfortunately, pulling back the curtain on anyone's quiet time can be stressful. The water was his only shelter, for those times when he wanted to be left alone. I hoped that Lolong would eventually get used to this; crocodiles are pretty good at adapting to routines even if they're less than pleasant, and the time he was exposed seemed to be relatively brief. Perhaps he could have adapted to this eventually, had he been given more time to adapt to his new home first. Sadly this was not to be. Another unavoidable consequence of Lolong sitting in shallow water for an hour or two every day was made apparent during his necropsy, where abrasion of the skin on his head, teeth, claws, pectoral and pelvic areas, and his toes all show the effect of a large, heavy crocodile forced to sit and move on unyielding, rough concrete. Internally many organs showed signs of bruising where Lolong's one tonne mass inflicted its toll on a body that was never intended to lie on a hard surface repeatedly. The final straw for Lolong may have been Typhoon Pablo which hit the Philippines shortly before Lolong's death, causing temperatures to drop and his immune system to take another hit.

These problems suggest, as some news articles have claimed, a callousness and disregard towards Lolong's well-being. I don't agree, and I think it's unfair. Anyone who actually met his caretakers would have realised he was well-loved. You might say they adored him. Not just because he put their town of Bunawan on the map, but because they were all clearly in awe of him. Clearly there were also financial incentives to keep Lolong alive; he was popular, brought much money into the community, and generated a lot of national and international attention. You don't kill the golden goose, so why would his caretakers wish to be careless? I put it down to inexperience, particularly towards the needs of large crocodiles in captivity. Perhaps those of us who advised them to make changes didn't state our case strongly enough, or encourage improvements to be made quickly enough. Crocodiles can easily lead their caretakers into a false sense of security, because it takes months for problems to become apparent on the surface. I saw Lolong two months after he'd been in captivity, after he appeared to be adapting well by eating and behaving normally. Routines such as draining the pool had been established (although I only learned of this later) and his caretakers perhaps didn't see any pressing reason to change this, causing subsequent concerns to be overlooked? Even then I hoped that Lolong would adapt to this routine, in the same way that captive crocodiles in zoos adapt to the stress of visitors constantly walking past their enclosure; they quickly learn that it's not a threat to worry about, and stress levels drop. The desire by his caretakers to keep the water clean was also admirable, because we're taught that dirty water equals disease, but crocodiles actually prefer murky water - it's a much better hiding place than clear water. Draining the water also drained whatever heat was in that water, and while the replacement water may have been at a similar temperature, it's another question mark over the need for this routine. Ultimately this was all too much for Lolong to deal with so soon after having been captured from the wild, all he'd known for over half a century.

Perhaps it was love that killed Lolong? A desire to keep his water clean and clear, and to show him off like proud parents ended up being too stressful for him so early in his captive life, before he'd had chance to really feel at home. I've read much criticism that his enclosure was too small and contributed to his death, but that's a red herring. Lolong's enclosure was actually relatively large compared to those provided to many other captive crocodiles in zoos, he had plenty of room to move around in the water and on land, and even though the pool could have been deeper it was really the constant draining that caused major problems. It's interesting that Cassius, the massive crocodile to whom the record for "world's largest" has now reverted, has been kept in a much smaller enclosure for nearly three decades now. He's doing just fine.

Lolong's death has inevitably raised questions about whether he should have been captured in the first place, and indeed whether any crocodiles should ever be kept in captivity. Animal rights issues aside, it seems many have forgotten the reason that Lolong was captured in the first place. He was a wanted crocodile; poison baits had been set out by the local community to kill him, and more direct methods would have been used if the opportunity arose. Few people will tolerate a killer crocodile in their midst, and why should they? Crocodiles that attack people develop a dangerous knowledge that humans can be easy prey, and it is well known that they will return to an area again in the future to look for more. This is a real fear for people who live alongside crocodiles, and no matter how much you love crocodiles it makes sense to remove such antagonistic individuals to better protect the remaining wild population, particularly in a country with little love for crocodiles in the first place. So what do you do when the wild population is so rare? It's a no-win situation. It would have been ideal to leave Lolong in the wild, but does such specious thinking have a place in our overcrowded world? Conflict between humans and wildlife can have major repercussions for conservation (not to mention human safety, which any level-headed human regards as being of prime importance). Yet at the same time we can't simply remove all wild animals simply because it makes us feel better, or safer. There has to be a compromise, and unfortunately for Lolong he was that compromise at that particular time and place. Perhaps his death can be a lesson for us.

Let us instead celebrate Lolong, and what he was able to achieve in his short time in captivity. It's testament to his ability to inspire people that the same animal who was once hunted for perhaps killing a nine year old girl and a fisherman caused a town to go into mourning when he died. Lolong, more than any crocodile before him in the Philippines, did what years of education by humans were struggling to do - change people's perceptions on a large scale about crocodiles. He was a true ambassador for crocodiles, and while some may see his enforced captivity as a bad thing, nobody can deny his unanticipated achievements for crocodile conservation in a country that has traditionally had a great mistrust of them. The government issued a resolution pledging to improve conservation for crocodiles throughout the Philippines, of benefit primarily to the endemic and critically endangered Philippine crocodile. The irony here is that the inoffensive Philippine crocodile has always suffered because of its association with the more aggressive and dangerous saltwater crocodile, but finally that association proved to be an asset through Lolong. So let's make sure it counts by not forgetting him.

(c) National Geographic

As a final note, now that Lolong has died the Guinness World Record for the longest crocodile in captivity reverts back to the impressive Cassius, a nearly 5.5 m (18 ft) saltwater crocodile living on Green Island in Queensland, Australia. Make sure you pay him a visit while you can. Yet Lolong remains, in spite of his death, the largest crocodile that has ever been accurately measured. I wonder if there's a record for that...?

*A necropsy is an examination of a body after death to determine the cause of said death. It's interchangeable with autopsy but necropsy is typically used when dealing with animal carcasses. It's one of those cool words that gets its brief moment in the limelight when something eventful like this happens.