Methodological considerations
The experimental design in this study is based on the integration of two
databases, which needs some consideration in interpreting the results of
this work. We censused the plots from which we obtained the data used to
model survival and growth from 2003 to 2016. In addition, for this
study, it was necessary to gather data on the presence and number of
reproductive structures in order to model fertility. These data had not
been previously recorded, thus in 2017 we sampled these variables in the
field. In that year, rains were recorded after several relatively dry
years, possibly associated with ENSO (Muñoz et al., in revision).
Therefore, it is important to note that the environmental conditions may
have been very different between the two sets of data that fed the
different models.
We carried out fruit counting and sampling in November, based on the
phenological behavior of the species at the study site (Maldonado,
2014). During fieldwork, we observed ripe fruits and some fruits on the
ground. Therefore, it is possible that the number of fruits counted may
be an underestimation of the actual number produced, and thus
underestimate f 2. No laboratory germination tests
were done for this species and no studies are known to have done so,
thus the conversion factor from seeds to seedlings was calculated using
inverse estimation (González, Martorell, & Bolker, 2016). Very likely,
the inclusion of an in situ germination study would produce
better germination estimates; however, inverse estimation is a good
approach in the absence of such studies.
Similarly, it is important to keep in mind that the database used to
model growth and survival is much larger than that for fecundity, making
it more difficult to identify outliers in fecundity. Therefore, we
cannot rule out that the low values observed in fecundity may be related
to all of the above. In order to better understand reproduction, it is
important to have a larger database and to consider different years of
sampling in order to have greater control over interannual variation.