Boning Up On Antlers Beautiful Racks Product Of Amazing Annual Growth

Sportsmen hunt for three reasons: pleasure, meat and trophy antlers, in degrees that vary from person to person.

But for all the hunters who seek a trophy rack, few know much about the remarkable appendages that make a trophy.

Antlers are the only organs in mammals that completely regenerate annually.

Fully developed antlers are dead bone. Antlers are the only type of dead bone any member of the entire animal kingdom can tolerate. All other animals will reabsorb it.

Antlers are not horns. Horns, like those on cows, are made of a protein found in hair that grows over a bony core. Horns grow from the base out, while antlers grow at the tips. Horns grow for the entire life of the animals.

Antlers are shed and regenerated each year.

There are 41 species in the deerlike family including the popular North American game animals. Two of the 41 species, Chinese water deer and musk deer, lack antlers altogether. In caribou, the females also grow antlers.

Antler growth starts in the womb where a microscope can reveal a change in cells of a certain area of the frontal bones called the pedicles.

Three to five months after birth, one can feel the pedicles where one day the antlers will emerge.

The pedicles are a special thickening of the tissue that normally covers all bones. Growth and development of the pedicles is related to proper nutrition and its effect on body weight. Body weight and nutrition in turn affect the onset of puberty and the production of male hormones.

Puberty, male hormones and sunlight are the keys to antler growth, it seems, but scientists still debate other hormonal and environmental influences. Changes in the amount of sunlight the animal receives (in the temperate zones) causes varying amounts of male hormones such as testosterone to be secreted. This is best understood if antler growth is looked at as an annual cycle.

Beginning with the spring equinox, testosterone levels are at their lowest.

The hard antlers are shed, the pedicles quickly heal and new antlers begin to grow immediately. During the spring and early summer, testosterone levels remain low and antler growth is explosive. Elk can add up to an inch a day. Moose will lay down almost a pound of new bone, blood vessel and nerve every 24 hours.

Virtually nowhere else in nature do these tissues grow as fast. As a result, antler growth has been a source of intense scientific investigation. After the summer solstice, testosterone levels begin to rise rapidly. The velvet antler begins to mineralize to a composition very similar to other bones in the body: about 25 percent calcium, 19 percent phosphorus, 39 percent organic matter and 8 percent water. Antlers have about the same tensile strength as a human shin bone, are less brittle than ivory, and are highly elastic allowing them to absorb impact. The antler is most brittle in autumn and winter because over time it continues to lose water.

Velvet is a type of skin that includes fine hair and glands that secrete oils. It is the only skin on the body that can grow new hair follicles as it regenerates.

As the days get longer and the antler starts to mineralize, the velvet begins to shrivel and die. Soon the animal will begin to rub it off and in so doing establish scrapes and rubs on trees. After the velvet is gone mineralization is completed just before rut.

The process of antler growth in elk takes from 138 to 177 days. Older males will shed their antlers sooner than younger males in the late winter and the process begins anew.

Many hunters believe antlers are exclusively a weapon for fighting among males and establishing dominance. While harem battles do occur, many more dominance disputes are solved by ritualized antler displays without contact.

Antlers do dissipate pheromones; a class of special chemicals produced by the animal to stimulate sexual activity. Members of the deer family also use antlers to scratch their backs and knock down fruit.

One of the most interesting studies on elk antlers was done to establish a relationship between age and size.

The study was conducted on 480 free-ranging elk on a hunting ranch near Raton, N.M. The researcher, Gary Wolfe, found a linear relationship between the length, weight and circumference of antlers and the animals’ age as confirmed by dental examination.

Antler size was found to increase each year until a bull reached 10.5 years old, then it declined.

The number of antler points peaked at 7.5 years and stayed there.

Ninety percent of the 6-by-6-point bulls in Wolfe’s study were at least 4.5 years old as were bulls scoring at least 300 Boone and Crockett points.

Wolfe summarized that the most desirable trophies were found to be between 7.5 and 10.5 years old.

Washington and Idaho have adopted spike-only elk hunting regulations for certain heavily used areas. The hopes are that this will take the pressure off the big, robust bulls that have survived nature’s own selection process. Most results show it seems to be working.