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The missing deer and the strange skull

Jake

Up until recently my trail camera has been watching a badger sett, which I wrote about here and here, but since the wood around there is being cut down it seemed the right time to move it to somewhere else, and my two little brothers, Sam (5) and Harry (4) asked if they could find somewhere to put it.

Dad took my brothers out to look for somewhere where they could leave the camera, and they went to the original pine marten wood, where I filmed a lot about two years ago. They were looking for somewhere where they knew animals might come to, and after searching the wood they found a quite fresh roe deer carcass, and left the camera there. But when they went back a week later, there was a surprise !


The roe deer body wasn't there any more ! That came as a surprise to this fox as well.


They searched the wood, but weren't able to find the body at all ! However, Harry did find this skull lying on the ground:


He brought it home - he knew it wasn't from the same missing deer - and then he and dad checked the trail camera. The day after it had been left, a fox came and dragged the roe deer body away.


That was one easy mystery solved, but what Harry wanted to know is: what had happened to this roe deer skull that caused the back of the skull to be missing ?


It's rare to find skulls with injuries like this. The first thing is that it must have happened either at the point of death, or after death. An injury like that wouldn't be survivable, and there are no signs of the bone regrowing.

Before I look at that in detail, there were some simple things which I could tell about the skull. First of all it was definitely a roe deer (from shape) and a female (no antlers or pedicles) and that it had lain in the wood for some time (because of the green growth over most of it).



The first and biggest clue to age in deer is always the teeth. At birth, the only teeth they have are the three milk pre-molar teeth. A couple months later, the first molar come through, and it's an adult tooth. At nine months, the second molar is through and by 13 months, all of the adult teeth are through. This deer had all the adult teeth, but they weren't worn down too much, so I guessed it was between two and four years old.


The two halves of the skull were pulled apart slightly, which showed the skull had been moved around a lot or dropped.

Another good way to tell the age is by looking at the two plates on the bottom of the skull. The one on the left, which runs horizontally, fuses when the deer is around 13 or 14 months old and the one on the right that runs vertically, fuses much later in life, and if you look closely, you can see that it's not fused.


So, that means that it was older then 14 months, but not very old when it died. 

From above there were not just one hole, but also two smaller ones on the top:



One possibility is that it was shot in the back of the head. That would cause a lot of damage. Another was that it was some kind of trauma (impact) at or after death.  But the closer I looked the more I realised that it wasn't that.

The clue was in these marks.  The green growth had occurred sometime after death, but the inside of the holes was still white, showing that the holes were made after the skulls had lain for some time. The other clue was in the marks at top left.


I recognised these: these were teeth marks ! Some animal had been gnawing on the bone, and had weakened it so much they bit through the braincase. Gnawing on bones may seen strange, but deer and other animals do it a lot to get calcium into their diet. This was an easy problem to solve once you knew what deer do - but a lot of people don't know about it !



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