Wildlife TV

Learn interesting and funny plant and animal facts with videos and photos

How do Blue Wildebeest Mate?

on July 23, 2013

Once again we will look at mating techniques in the animal kingdom. In previous posts in this series, we’ve seen how the physical act of mating is achieved by overcoming anatomic limitations in porcupines (Genus: Hystrix) and hippopotamuses (Hippopotamus amphibius).

Aside from the the act of copulation itself, mating is also about selecting appropriate partners with which to produce offspring. In this article and the next, we will look at African antelope and the different strategies they use in selecting mates, sometimes violent and sometimes peaceful.

Blue Wildebeest (Brindled Gnu)

The Blue Wildebeest (Connochaetes taurinus) is an instantly recognisable African animal and besides playing an unfortunate role in the death of Simba’s father, Mufasa, in Disney’s The Lion King, they are noted for the vast herds which they form during East Africa’s Great Migration. However, the huge, groaning herds of wildebeest during the migration are not the usual social structure in which these animals live; blue wildebeest usually live in smaller groups (depending on their habitat). Cows, sub-adult bulls and calves group together in herds and the adult bulls live away from them, mostly in bachelor herds, but as they get older they will live alone in their established territories. However, adult bulls and cows must come together in order to mate and reproduce, supposedly after the first full moon following the end of the rainy season, and it is this act that we are interested in today.

A herd of Blue Wildebeest (Connochaetes taurinus)

Blue Wildebeest (Connochaetes taurinus) can form very large herds, mostly composed of cows and younger bulls.
Photo Credits.

At around the age of 5, a wildebeest bull becomes strong and confident enough to try to establish a territory out on his own, away from the bachelor group with which he probably spent the last 4 years or so. The male’s aim of establishing a territory is to secure an area that would appeal to the females so that they would come and live with him and, in turn, mate with him. The females know what they like, they will be attracted to areas that have a plentiful source of food and water and are as safe from predators as possible, but these criteria are not always easy to satisfy and the best spots are few and far between which means that the males will have to compete for them.

Dominant bulls establish and assert their territories in a number of ways and they have physiological adaptations that help them; it’s not a simple case of fighting over who’s in charge. Wildebeest bulls are equipped with glands on their faces called preorbital glands, these produce secretions that are loaded with a cocktail of pheromones and other chemicals that release strong enough smells to mark ownership of an area. Bulls will rub their faces against solid surfaces and vegetation around their territory to deposit these chemicals and advertise to females as well as ward off rival males. They also have glands between their hooves called pedal glands that provide the same function, but allowing the animals to scrape their scent into the ground. They will also scatter their dung around, sometimes even rolling in it to acquire and disperse the scent as much as possible. One interesting behaviour that the bulls employ is to rub their horns against trees and scrape away the top layer of bark to leave a signpost that is visible from a distance, they will even select trees that have a red inner-bark as these will be more visible.

A Blue Wildebeest (Connochaetes taurinus) rolling in dirt after scent marking.

Blue Wildebeest (Connochaetes taurinus) will often roll in the dirt after marking it with their scent, either with dung or glandular secretions.
Photo Credits.

It’s not enough for a bull to decorate his territory and advertise it to potential mates, he will also have to defend it against rivals that would steal it away from him. This competition can often take the form of a physical contest wherein males with grunt and scrape at the ground to demonstrate their strength in the hopes of intimidating each other, culminating in a joust where they crash their horns together and attempt to push each other into submission. A male who has successfully held his territory will announce to females all around by calling and making a “ga-noo” sound repeatedly (this sound is where wildebeest get their alternative name, Gnu). If his territory is appropriate and he can keep it, his calls will eventually attract herds of females and he can mate with them; the females have selected a strong male who can defeat rivals and will be able to drop their young in a suitable area.

Two Blue Wildebeest bulls (Connochaetes taurinus) engaged in a duel

Blue Wildebeest bulls (Connochaetes taurinus) will engage in fierce battles to secure territory and mating rights.
Photo Credits.

Wildebeest males put in a great deal of effort to prove their worthiness to sire young, but all of their struggle proves to the females that they are the best candidates for producing fit and strong young.

I hope you enjoyed learning about these animals. In the next post we will look Nyala ((Tragelaphus angasii), another antelope with a much more peaceful approach. You can read more about other mating techniques on our series page.

Much love,

-Nick

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: