Eared Quetzal frequently is described as rare: very local, with low densities, and dependent on undisturbed habitat (Zimmerman 1978, Russell and Monson 1998, Johnsgard 2000). Although they are apparently rare in the state of Sonora, which is at the northern edge of their distribution (Van Rossem 1945, Russell and Monson 1998), this may not always be true. Lammertink et al. (1996) found it to be unexpectedly common, saying it was difficult in their study to find an area with no Eared Quetzals. They found the bird in 31 sites of primary forest and 21 sites of secondary forest, and calculated the number of encounters per 100 hours in the three different montane habitats during different times of the year in the following table (in parenthesis are the total birds observed and the total number of hours spent in each habitat):
|canyon forest||dry-open forest||mesa forest||X^2|
|Oct.-March||(45/130) 34.6||(11/116) 9.5||(2/61) 3.3||34.7, P<0.01|
|April-June||(9/56) 16.1||(3/40) 7.5||(6/92) 6.5||5.5, N.S.|
|July-Sept.||(14/68) 20.6||(2/47) 4.3||(0/0) --||10.7, P<0.01|
|Year round||(68/254) 26.8||(16/203) 7.9||(8/153) 5.2||20.8, P<0.01|
Lammertink et al (1996) suggest that the quetzal may have previously been overlooked due to its wariness, but that it is widely distributed and a common bird in primary canyon forest that was also frequently observed in disturbed forest. Its population could also be regarded as stable, because its riparian habitat is not at serious risk (Lammertink et al. 1996).
After studying their breeding biology and seeing very high nesting success rates, Gonzalez-Rojas et al. (2008) suggested that the factors limiting Eared Quetzal population were likely nest failures due to the falling of rotting nest trees and the availability of nest holes.
No information found on the age at first breeding, life span and survivorship, diseases, parasites, or causes of mortality for Eared Queztal.