Over the past few weeks, the large majority of migratory birds at Londolozi have arrived. There are around 66 different bird species that join us here at Londolozi for our summer months. Some earlier than others, some to breed and some to feed on the abundance of insects that emerge with the warm wet summer weather. Each and every one of them having its own interesting story.
But there is one I want to focus on today, the Wahlberg’s Eagle. These medium-sized birds of prey move steadily southwards over the equator from their winter hang-outs in Central, North and West Africa (countries such as Nigeria, Sudan, Cameroon, and Chad), making use of familiar landmarks they have flown over on many similar journeys, heading ultimately to the same nests they have used on many occasions before.
Wahlberg’s Eagles breed in southern Africa, where they travel back to the same area year after year to reuse the exact same nest as before. This means that we get to recognise the same individuals that return. One satellite-tracked bird traveled from the Kruger National Park via the DRC all the way to Chad in 42 days. One can only imagine the challenges this bird went through on its long journey.
Plumage colour can vary greatly amongst Wahlberg’s Eagles, with some being dark brown and others being very pale. Like most eagle species, Wahlberg’s are monogamous, mating for life, and they return each year to re-claim their particular patch of African bushveld in order to breed and raise a chick before winter returns and food availability drops.
One of the main reasons these eagles arrive early in the season is to make the nest ready for breeding, which they do by gathering extra sticks and small branches to repair some of the damage of the six months they have been away. Once the egg has been laid (it is almost always only one egg that is laid) it is a further 44-46 days before it hatches, after which the fledgling period is around 70 days before the young bird leaves the nest.
The adult pair divide parental responsibilities during this period, with the male doing most of the hunting and the female most of the incubating. The male returns with the food which the female then tears into more manageable pieces for the chick to eat.
After a successful breeding season, the Wahlberg’s Eagles then return further north to spend the cooler months in an area of warmer weather and more abundant food sources. There they will remain for southern Africa’s winter, roaming many thousands of square kilometres, gathering their strength to embark on the long journey way south to repeat the cycle all over again.