The bluish bill and dark cap help identify this species. They are relatively scarce here and these were the only ones we saw. Sexes are similar but the female averages slightly paler suggesting the front bird is probably female. Digiscoped with Panasonic DMC-LX5 | Nikon FieldScope III | 30XWA | hand-held (no adapter).
References:
Carboneras, C. & Kirwan, G.M. (2018). Hottentot Teal (Spatula hottentota). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/52889 on 5 July 2018).
Hockey, PAR, WRJ Dean, and PG Ryan, eds. 2005. Roberts' Birds of Southern Africa. 7th ed. Cape Town: John Voelcker Bird Book Fund.
Sinclair, I., Hockey, P.A.R., Arlott, N. (2005). The Larger Illustrated Guide to Birds of Southern Africa. Struik, Cape Town