Shortly after the zoo opened on April 17, 2013, the right antler of a two-year-old male Hokkaido Ezo Sika Deer "Q" fell off in the Ezo Sika Deer enclosure in East Garden Ueno Zoo. The next morning, April 18, his left antler also fell off.

Deer with antlers shed and replace their antlers every year. After the old antlers fall off, new antlers covered in velvety skin (velvet antlers) grow. These velvet antlers are lined with tiny blood vessels, and the nutrients carried by the blood help the antlers grow. Before the breeding season, the antlers stop growing, harden like bone, and the skin peels off to form new antlers. The completed antlers fall off around the end of the breeding season, and the cycle of new antlers growing again repeats.

The timing of antler shedding and velvet antler growth varies slightly depending on the species, individual, and age, but in the case of Ezo Sika Deer, antlers generally fall off between March and May, and velvet antlers grow back immediately afterward.

Last year, Q was still young at only one year old and had small horns, so he didn't seem to notice that his horns had fallen off, and there were no particular changes before or after the horn loss.

This year, he has grown impressive antlers compared to last year, and when Nagi (male, 4 years old), Japanese Serow he lives with, approaches, he can be seen lightly shaking his antlers to chase him away. He is often found on the top level of the stepped enclosure and has a confident demeanor, but the moment his antlers fell off, he showed signs of weakness and now spends more time sitting in the bottom corner of the enclosure.

The relationship between Nagi and Q also reverses before and after antler shedding, with Nagi sometimes chasing Q. Their behavior seems to change as their antlers grow. Q's velvet antlers will also grow larger in the future. Please keep an eye on them.

Please note that currently, we are allowing Q free access to the bedroom while monitoring her condition, so she may be difficult to see at times. Thank you for your understanding.

Top photo: When it has horns (taken on January 16, 2013)
Photo below: When the right corner fell off (taken on April 17, 2013)

[Natsumi Uno, Animal Care and Exhibition Staff, Ueno Zoo, Ueno East Garden]

(April 26, 2013)