Autumn − Mushrooms and Mating

In the autumn, reindeer are at their best condition. The heat of the summer and insects are way past. The females that have calved in the spring and lost up to 20 % of their weight over the summer due to suckling, have regained their energy and are stronger again.

The condition reindeer reach in the autumn has an effect on reproduction and calving in the coming spring

There are still plenty of green plants to eat even though the high season is over. When there is an abundance of mushrooms, reindeer spread out to forests and fells to eat the mushrooms and this increases their fat layer for the winter. The most delicious mushrooms for reindeer are boletaceae mushrooms, but others do as well.

In autumn reindeer move around looking for mushrooms. Image: Marja Anttonen.

It is most important for male reindeer to eat and rest. During the mating season, they do not really have time to eat. The battles between the male reindeer can last hours and they use a lot of energy. Some males may have difficulties to survive over the winter after the rutting season

Female reindeer can have their first rutting season already in their first autumn, if the conditions are good. Normally, reindeer are mature after their second summer at the age of 1.5 years. The female reindeer have to collect enough fat and weigh over 60 kilos to be in heat. The peak period of the rutting season is in the beginning of October and it lasts around a month.

Rutting Season – Rykimä

When the rutting season approaches, the looks and behaviour of the male reindeer change. They formulate herds of 10-20 reindeer. The male rutting season starts in September and female follow a couple of weeks later. The “rykimä” name describing the rutting season comes from the sound that the reindeer make. The most powerful males collect female and guard them carefully from competitors. The female are welcomed to the harem, but they cannot leave before the rutting season ends. The male will guide a female back if it seems to be leaving.

The male reindeer rub their antlers and prepare for the rutting season fights. Image: Kari Henttunen

When a competing male approaches, they step next to each other and test the powers. If the other is clearly weaker, they will step aside. The more equal males will turn against each other and hit the antlers together. The winner may change between the rounds, but they will not stop before the final winner is solved. Equal males can continue to fight for hours and continue again in the morning. In the end, the weaker male has to step aside.

The males confront each other and try to unbalance the opponent by using their antlers and their own body weight. Image: Sonja Kyrönniemi

The aggressiveness and strength of the males are at their height in the rutting season. It is obvious that due to the sharp antlers, both parties follow the etiquette that has formulated over the decades. Harming the competitor is not the aim. Sometimes there are accidents that lead to the death of one of the parties. In these cases, the antlers get stuck permanently together or they may stick them through the rib of the competitor.

During the rutting season, it is good to be careful with male reindeer and their harems. It is better to step aside and pass them from a long distance. If you go too close, the male can presume you are a threat and attack.