Highland Wildlife Blog: Antler anomalies
December 16, 2015 § Leave a comment
Douglas Richardson, Head of Living Collections, RZSS Highland Wildlife Park
Since 2008 we have been collecting some basic data on the antlers of our various deer species at RZSS Highland Wildlife Park. There was no specific reason for gathering the information, other than the philosophy that there is no such thing as useless information and one cannot necessarily predict what may or may not eventually become valuable data.
Deer antlers differ from cattle, sheep or antelope horns in that they are grown and shed annually, whilst horns grow almost continually through the animal’s life and are never shed. When a deer drops its antlers in winter at the end of the breeding season, after a few weeks antler buds appear covered in a velvet-like material, a valuable commodity in Chinese traditional medicine, which is suffused with a blood supply that feeds the growth of the antlers. When the antlers reach their full size for that year (they are generally bigger or have more points each year), the “velvet” is rubbed off by the deer to expose the hard, bony antlers. In our data-set, we record the date the individual strips the velvet and goes into hard antler, the date it loses its antlers and the antlers’ weight.
An aggressive, territorial stag can overnight become a meek and mild shadow of his former self as soon as his antlers fall off his head, practically like throwing a switch. I once got a call from a keeper to come and look at one of our big reindeer bulls who was acting strangely. The keeper had noted that his head was shaking a bit and that there may be a neurological problem. When I saw the deer I asked when he had shed his antlers (forest reindeer antlers are particularly massive), and I was told that it had happened the day before. The animal had been carrying almost 10 kg in weight on his head for some months and all of a sudden it had been “removed” and his neck muscles were just taking a bit of time to get used to the new situation; the animal was fine within just 24 hours.
On 21 November we had an unusual event when the bull elk, or moose, dropped his antlers, which was a tad early. We consulted the antler chart and he normally shed them in February, with one pair lasting until mid-March. Our first thought was that he may be poorly, but he is in very good physical shape, his appetite is robust and he is actively associating with the adult female and twin calves. We also noted that the young adult male red deer were hanging about quite close to the female herd without being actively chased away by the herd stag; normally the red deer rut would still be in full swing.
Are these premature shifts in what are normally much later physical and behavioural events just the result of a mild November, or are they possibly indicators of climate change? The continued entry of each year’s antler data into our chart may yet prove to be more enlightening than we first anticipated.
This piece was first published in the Strathspey & Badenoch Herald