Nature Blog Network

Friday 13 November 2009

Giant Snakes - for Goodness Sakes

Initially, I must say I am very grateful to Matt Pickering for bringing this to my attention. He forwarded me a post about this photo, supposedly from China which shows a giant 55ft long “boa”. Seeing as no-one has really taken a constructive look at this, I thought I would start something.

The text below is from Ananova.com, and most of it is reproduced below:

“It was originally posted in a thread on the website of the People's Daily, the official Communist Party newspaper in China. The thread claimed the snake was one of two enormous boas found by workers clearing forest for a new road outside Guping city, Jiangxi province. They apparently woke up the sleeping snakes during attempts to bulldoze a huge mound of earth. "On the third dig, the operator found there was blood amongst the soil, and with a further dig, a dying snake appeared," said the post. "At the same time, another gold coloured giant boa appeared with its mouth wide open. The driver was paralysed with fear, while the other workers ran for their lives. "By the time the workers came back, the wounded boa had died, while the other snake had disappeared. The bulldozer operator was so sick that he couldn't even stand up." The post claimed that the digger driver was so traumatised that he suffered a heart attack on his way to hospital and later died. The dead snake was 55ft (16.7m) long, weighed 300kg and was estimated to be 140 years old, according to the post. However, local government officials in Guiping say the story and photograph are almost certainly a hoax as giant boas are not native to the area.”

Make of the story what you will, but for this I will just stick to working out what the snake species is, and how large it is. First, just to get our bearings, Jiangxi is in the South East of China. This area does have some huge snakes, but not large boas. No Chinese boa would ever get to 55ft. A python would have to be the culprit. Burmese pythons (Python molurus bivittatus) are the largest species that definitely occurs in the region, but Jiangxi lies close to the ranges of the Indian python (Python molurus molurus) and the giant reticulated python (Python reticulatus). All these species get to 16ft, but the Burmese and reticulated can get larger; up to 30ft (the reticulated is usually longer and currently holds the title of the world’s largest scientifically verified snake). Giant snakes over the 30ft mark have been reported from South East Asia, the naga could well be a giant species of python, so clearly a 55ft long snake would be of major cryptozoological interest.

But does the snake species pictured match any of the three largest snakes from the rough area? Well, looking at the back of the python, it has large dark blotches along its length that get larger toward the middle of the snake. The blotches are a brown-grey colour in the centre, with black margins then going to pale. There are smaller dark markings in this pale area which seem to follow a line between the large blotches and the pale underside. The underside is paler and seems to have some small spots of dark pigment on, a peppery effect if you will. Red blood can be seen coming from the snake’s mouth. The snake is fairly slim, but it has a thickened “saddle”, suggesting it is in the process of digesting a meal.

Burmese pythons have very similar blotches on their back that would certainly fit in with the blotches in the photo. They also have paler undersides, but they can be very variable in colour. Usually the markings in-between the blotches are darker than the snake in the photo, but their variability over such a large distribution range, including the region where the photo is supposed to have been taken, makes them a strong contender for the individual photographed.

Indian pythons have very similar markings to the Burmese, but tend to be darker overall with less mottling. Because the snake in the photo is quite light in colour, it is more likely to be a Burmese than an Indian, plus the Indian’s range is more southerly than Jiangxi. This pretty much rules the Indian python out as a candidate.

Reticulated pythons have very similar blotch markings to the Burmese, but usually have a distinct yellow-green background colour in contrast to the Burmese’s usual pale brown background. These snakes are also variable in colour, but not to the extent that Burmese pythons are. Reticulated pythons also occur further south than Jiangxi province, making their presence there unlikely. Of the two species, I would say the Burmese python is more likely to be the species in the picture.

But how big is the snake in question? The first thing to note is that the photo has been taken with a wide angle lens. The slightly oddly shaped foliage to the left and right of the image results from the bent effect that wide angle lenses achieve to get more image in the frame. These types of lenses also shorten the apparent distance between the foreground and back ground, making objects in the foreground appear larger, and those in the background appear smaller. Making measurements on a zoomed in version of the photo, the snake is roughly 43cm long, adding 5 cm for the rest of the tail which is not in the photo. Using 55 feet as a reference, the people in the background are therefore 4.8cm tall, or just over 6.1 feet tall (conversion factor of 1.279). This is an estimate based entirely on the image itself with no allowances.

But, although this measurement puts the men at the back of the photo into a size range appropriate for a human, the digger poses a problem. It is not a large model, being very flat to the ground. Now look at the scoop. Any digger of the size apparent in the photo would topple over as the scoop reaches out. Using the above calculation, the scoop appears to be 8.18 feet wide, a monstrous scoop! With the same calculation, the digger is 8.69 feet wide, in other words, way too small to support a scoop nearly as wide as itself! Looking at the thickness of the arm compared to the thickness of the digger, the scoop must be smaller than 8 feet. Being vaguely familiar with diggers, and having a similar size digger at my old employers, the scoop is probably in the 3 foot area, perhaps a little larger. For the purposes of simplicity, and to be generous, let’s call the scoop 3.5 feet wide.

Now using this as a length indicator, because the scoop and snake are the same distance away from the camera, the measurement will not be affected by the lens. 26.5cm is the length taken for the snake, and 5cm for the scoop. The snake is 5.3 times the length of the scoop, so roughly a 18.55ft long snake. Or, a perfectly average sized adult individual for either a reticulated or Burmese python. Even if the scoop was 4 feet wide, the snake would be 21 feet long. To get the reported 55ft, the scoop would need to be over 10 feet wide! For a new world record holding snake at 34 feet, the scoop would need to be 6.4 feet wide, a very big scoop and one totally impossible for the size of the vehicle. This is a hoax; it merely shows an average to moderately large individual of a well known species.

If I was to make a guess at the species shown, I would go for the Burmese python based on the distribution of the animal, and that the markings between the photo and the species match very well.