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Range DescriptionRhynchopsitta terrisi is restricted to the Sierra Madre Oriental in Nuevo León, Coahuila and Tamaulipas, Mexico, where there is presently no more than 5,000 km2 of suitable habitat (R. Valdés-Peña et al. in litt. 2007, 2010). During winter 1998, some birds were recorded in the Sierra Gorda, Querétaro (R. Pedraza in litt. 1998), suggesting wanderers reach the south of the Sierra Madre Oriental. By 1998, 21 colonies had been identified (Snyder and Enkerlin 1996, Macias Caballero 1998), with 23 known by 2006 (Ortiz-Maciel et al. 2006), but it is still unclear whether it breeds c.25 km south of that range at Cerro Potosí. Counts of large wintering aggregations and productivity data from 1996 to 2007 suggest that the known colonies could account for almost the entire breeding population (R. Valdés-Peña et al. in litt. 2007, 2010). There are four main colonies (El Taray, El Condominio, San Antonio de la Osamenta and Santa Cruz [Macias Caballero 1998], with El Taray the most important [Valdés-Peña and Ortiz Maciel 2007]). Population estimates are hampered by its seasonal movements, but numbers were put at 2,500-3,000 individuals in 1996 (Macias Caballero 1998), and c.2,500 individuals following surveys in 2006-2007 (R. Valdés-Peña et al. in litt. 2007, 2010). An estimate of c.3,500 individuals was put forward in 2008 (Valdés-Peña et al. 2008); however, given that the species is thought to reach reproductive maturity at around four years, there are probably fewer than 2,500 mature individuals (R. Valdés-Peña et al. in litt. 2007, 2010). Comparisons with the 1,400 and 1,600 birds estimated in the 1970s indicate that population levels were relatively stable up until the mid-1990s (Snyder and Enkerlin 1996, Macias Caballero 1998). However, numbers of breeding pairs at known colonies have been declining, there is poor breeding success and the species's habitat is being destroyed (R. Valdés-Peña et al. in litt. 2007, 2010). It appears that less than 10% of the population is breeding successfully each year (R. Valdés-Peña et al. in litt. 2007, 2010).