The species is found in arid or semi-arid lowlands, especially scrubby woodland with cactus, and also broadleaf, pine or mixed forest up to 800 m (Cleere and Nurney 1998; Cleere and Sharpe 2020). It perches inconspicuously by day on branches close to the ground. It is crepuscular and nocturnal, calling at night.

Siphonorhis brewsteri is found in central and west Dominican Republic (particularly on the north slope of the Sierra de Baoruco, between Oviedo and Pedernales, as well as near Furnia de Gurabo), Haiti (between Arcahaie and Montruis north of Port-au-Prince) and, in the past, was numerous on Ile de la Gonâve (Raffaele et al. 1998; E. Fernandez in litt. 2020). Its status in large parts of Haiti is however unclear by now (Cleere and Sharpe 2020).

Conservation Actions Underway
The species occurs in the Sierra de Bahoruco National Park (Dominican Republic). 

Conservation Actions Proposed
Conduct surveys to obtain more precise range, population and trend estimates. Assess the species's status in Haiti, including Gonâve Island. Investigate the causes of the population decline to quantify the relative impact of habitat loss and predation. Prevent habitat destruction at key sites. Consider trapping introduced predators at key sites.