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.

A monster crocodile in Toledo

In late 2012, Toledo Zoo contacted our company looking for an adult saltwater crocodile for their forthcoming Wild Walkabout exhibit. They weren't looking for a particularly massive one, only about 4 metres (about 13 feet long). I figured we could do a bit better than that. It just so happened that I knew of an awesome 5.2 m (17 ft) saltwater crocodile that was whiling away the days in a muddy pool in captivity, an animal that had been removed under license as a "problem crocodile" from a landowner's property a couple of years earlier. What better role than as an ambassador for how awesome crocodiles are (and how many big crocs there are in the NT!) for Toledo Zoo? It didn't take long for Toledo to upgrade their ambitions, and so began the long process of arranging the transport of a massive crocodile halfway around the world. We've done this before several times, but each transport presents its own challenges. The main priority is to make sure the crocodile is happy and has a stress-free journey, something we've gotten down to a fine art. In fact the only issues were some last minute bureaucratic mix-ups, but these were sorted in the nick of time and it all went as smoothly as could be expected. "Baru" (as he is now known) is happily exploring his new million-dollar facility at Toledo Zoo. I think most of us would be quite happy with a million dollar home. So now you have an excuse to visit Toledo and visit Baru. The rest of the zoo is also very good, I was really impressed with some of the innovative designs and behavioural enrichment ideas that I saw, and their conservation breeding program is world-class (eg. Kihansi spray toad reintroduction).

Here's the news story that the Toledo Blade published which shows some of the transport and offloading process. They got a few figures wrong, including the fact that the journey actually took over 50 hours, not 30 hours. They also didn't mention the part on the 15 hour international flight where the captain announced to the entire passenger compartment that they were sharing a flight with a very large saltwater crocodile. There was audible gasps.

A Night for the Crocs

Adult Tomistoma, Photo (c) Soham Mukherjee

I should have posted about this earlier, but recent events have made the last few weeks a little hectic. This Saturday 16 February an event called "A Night for the Crocs" is being held at Zoo Miami in Florida.

There are all kinds of activities for kids and adults alike, and best of all the proceeds for the event will be used by the Tomistoma Task Force of the IUCN Crocodile Specialist Group for direct action to conserve the endangered Tomistoma (false gharial) and its peat swamp forest habitats in Malaysia and Indonesia.

I won't duplicate any more information from their website, so go and check it out here. Sounds like a lot of fun for a good cause, and you can't argue with that!

So long, Lolong

Sadly, Lolong the record-breaking 6.17 m saltwater crocodile caught in the Philippines in September 2011 died last night around 8 pm local time. There's a lot of speculation about the cause of death, but until a necropsy has been completed, we won't actually know what killed him. Ronnie Sumillar, the local expert who led the capture effort, is conducting the necropsy. I'm sure this is not what he wanted to be doing today.

I'll write a more detailed post when more has been confirmed.

CrocLog Podcast Episode 13

As promised, here's Episode 13 of the CrocLog Podcast. This is a special edition that focuses on the Christmas Croc Fest 2012, and we speak with one of the organisers Shawn Heflick who is hosting the event at his place in Florida. Some of you might know Shawn as one of the hosts of The Python Hunters which airs on Nat Geo Wild in the US and National Geographic Channel in the UK, and he's a bit of a croc fanatic.

Next up in December is our Christmas Special where we'll be answering a lot of questions from our listeners. It should be a fun time, so watch this space.

Click below for the podcast, plus links to where you can learn more about the Christmas Croc Fest 2012.

CrocLog Podcast Episode 12

It's nearly Christmas, and that can only mean not one, not two, but three CrocLog Podcast episodes over the next few weeks! Here's the first one, Episode 12, which is a nice long one to make up for the interval since the last one. Episode 13 will be coming shortly afterwards and is much shorter, where we'll be talking about an upcoming fund-raising event for crocodiles.

In this episode we interview Subir Chowfin about his work on gharials in the Corbett Tiger Reserve in India. Brandon and I also bring you up to date on the latest crocodile news, some interesting recent research on crocodile sense organs, Brandon updates us on crocodile attacks, and I try my best to keep the distracting noise in my microphone to a minimum. The wonders of modern audio technology.

Links to the podcast and a few of the stories below:

Crocodile skin is more sensitive than your fingertips

Crocodiles are covered in a scaly skin. And on each scale are tiny pressure receptors called ISOs, or "integumentary sense organs". These are very densely packed onto the scales around the jaws, but can also be found across the whole body. Well, except alligators and caimans. For reasons that aren't entirely clear, alligators and caimans have no ISOs on their body scales, only on the head.

It's been known for decades that ISOs are sensitive to pressure. They function as mechanoreceptors, which means that when they are deformed by pressure, they send a signal to the brain. Touch something with your fingertip - the texture you're feeling is the result of tiny deformations causing nerve signals to be sent to the brain which interprets them appropriately. As a result of this study, we know that the pressure-sensitive ISO organs on the head and jaws of crocodiles are so good at detecting pressure changes, they are even more sensitive than human fingertips. That's pretty darn impressive. Earlier work suggested that ISOs served to detect pressure changes at the water's surface, but this latest study proves they're a lot more versatile than that. They can detect a wide variety of touch sensations, pressure changes, and vibrations. Everything from delicately manipulating hatchlings to detecting minute pressure changes created by fish swimming past their jaws in the water. And more. We're working on one particular study at the moment that has just had a lot of light shed on it by this news.

Impressively, the study also clearly shows that the ISOs on the body also function as mechanoreceptors. The feet in particular are very sensitive, and could detect pressure changes in the water (and certainly touch). I once described the crocodile as being surrounded by a pressure sensitive net, so it's very cool to see the science behind it detailed so thoroughly and effectively.

I strongly recommend that you read the full paper at the Journal of Experimental Biology. There are some very cool diagrams of nerve networks, and it will really give you an appreciation for just how remarkable the ISO system is for crocodiles.