Blackish Nightjar has a very large geographic range, and the population trend is believed to be stable. Consequently the IUCN Red List conservation status of Blackish Nightjar is evaluated as Least Concern (BirdLife International 2014).
The relative abundance of Blackish Nightjar is assessed as common to abundant in suitable habitat across its range (Cleere 1998).
Effects of human activity on populations
Blackish Nightjar often moves into areas disturbed by humans including trails, dirt roads and airstrips (Cleere and Ingels 2004, Ingels et al. 2009). Blackish Nightjars utilize weed beds beside quiet roads, man made clearings and excavated gravel pits for nest and foraging, and sometimes are found in large numbers around these sites (Ingels et al. 1999). As no population estimates have ever been made, it is difficult to know whether humans have allowed this species to become more abundant by increasing desirable habitat, or if complete habitat destruction throughout the range has led to an overall population decrease.