My wife, who is a long-distance cyclist, has reported the same high bird mortalities over a much wider area - she has cycled between Maun and Shakawe, Maun and Kasane, the Trans-Kalahari Highway and other routes and readily notices dead birds due to the (relatively) slow speed at which she cycles. In addition to hornbills, she has seen many Lilac-breasted Rollers, and various owls and nightjars, and a few years ago, large numbers of Barn Swallows following an early cold spell at the end of summer. She has also reported numerous snakes being killed, notably Puff Adders, and often Porcupines, Brown Hyaenas, Aardwolf and Bat-eared Foxes.
It is not known whether the effect of these mortalities on wildlife is sustainable, or whether it is depressing some populations. The latter is likely to be the case with globally threatened birds such as the Bateleur, and White-backed and Lappet-faced vultures, where numbers may already be low and/or declining due to a variety of threats. These birds sometimes scavenge along national roads and are susceptible to collisions with vehicles.
A beautiful chestnut-backed male Bateleur killed near Nata.
All sensible drivers in Botswana avoid driving at night due to the high probability of hitting a cow or donkey; we also need to take special care when driving during the day. Apart from the impact of roadkill on globally threatened birds and other animals, the impact of a 6kg vulture smashing through your windscreen will not do your vehicle much good either.It's in everybody'y interest to drive carefully . . .