Gray Go-Away-Bird

In June of 2018 we were visiting Hwange NP in Zimbabwe. We encountered some gray go-away-birds which look brown in my photos. There are four subspecies and it looks like we saw Crinifer concolor bechuanae, found from south Angola and northeast Namibia to Zimbabwe and north South Africa. Males and females look similar. They are an almost uniform smoky-gray color with long tails and a wispy back-swept crest  which can be raised almost vertically when excited (see the illustration below). They have a black decurved beak and the gape (interior of the open mouth) and tongue are pink. The plumage is darkest on the chin and throat and palest around the eyes and on the belly. The breast is washed slightly olive. 

We were in bright early morning light which is why they look so brown. 

Gray go-away-bird illustration from Birds of the World. 

Range map from Birds of the World.