The change of the seasons is upon us, and as we begin to transition into fall, the elk make a fine symbol of that change as they shed their velvet in preparation for the annual rut season. Outside of the golden turn of the aspen leaves, there is no more significant occurrence that symbolizes fall in the Rockies like the haunting sound of elk bugles and the clattering of antlers.
Antler growth in all of its phases is directly related to hormones, which are interestingly triggered by available daylight. In the spring, longer periods of light send signals from the optic nerve to the pineal gland causing it to increase melatonin production (the hormone that regulates sleep cycles) causing a slight increase in testosterone which triggers the initial growth of the antlers. As daylight increases, hormone levels settle back to lower levels and remain “stable” as the antlers develop. As light decreases in the fall, this sends another signal to the brain to produce higher levels of melatonin, which tells the hypothalamus glad to produce gonadotropin-releasing hormone (GnRH). GnRH then travels to the pituitary gland telling it to produce greater levels of luteinizing hormone, which drives testosterone production in the testes. The increased testosterone then triggers all manner of physical changes in the bulls (or bucks, bull moose, etc., and is the same basic process for all members of the deer family) in preparation for the rut, including the shedding of the velvet.
Within a few weeks those testosterone levels reach their peak, which creates a literal craze in the bulls as they exhibit very increased aggression in their bid for the right to mate and carry on their lineage. As we are not quite in that peak yet, this shedding of the velvet allows the bulls to return to their bouts of sparring, which they tend to do on and off throughout the duration of the antlers. These sessions have always come across to me as training for the battles that occasionally take place during the peak aggression during the rut, but as opposed to training for an actual fight, these sessions have more of a feel of “fight safety” rather than “how to fight to win”. Being that the intent of the rut battle is not in any way centered around harming ones opponent and more about simply establishing dominance, safety seems to be quite key.
Watching bachelor herds perform these sessions many different times over the years, it becomes apparent over time that they seem to be practicing squaring off and “locking up” their given “weapons” in a way that doesn’t cause harm to one another, especially something like losing an eye, which would seem quite common if the fights were actually about harm (and good reason for naming the first tines on an antler the “eye guards”). This is not to say that rut battles are harmless, as injuries certainly do occur from time to time, but with any wild animal, even a slight injury can be fatal for a number of reasons, and such injury or death can also end up diminishing the vitality of the greater herd health.
These members of a small bachelor herd found in a secluded meadow high in the park were displaying just such safety measures as the younger bulls took turns squaring off with their elders to practice their techniques. There was no real aggression or even any small amount of pushing about, which seems to be much of any true rut battle. While these sessions sometimes include pushing and shoving, this particular evening seemed to focus on basic head/antler placement in ways that prevent injury as opposed to causing it, and proved a valuable and enlightening insight into the lives of these majestic creatures.
Originally published in The Mountain-Ear
