Falcón L. et al. Acquired interspecific interactions can influence population growth rates in non-indigenous plant species
SUPPLEMENTARYMATERIALS
S1:Methods for estimating the fecundity values for the different size classes under field and experimental conditions.
S2:Methods for estimating the elements of the size-structured transition matrices.
S3:Projection and elasticity matrices of Spathoglottis plicata derived from the size-stage transitions from the field data collected in this study, and fecundities estimated from the field data in this study, and from exclusion experiments (spreadsheet file).
S4:Variation in survival and reproduction metrics of Spathoglottis plicata recorded during the demographic study period in the Río Abajo State Forest (Arecibo, Puerto Rico).
S5: Summary statistics (mean SD) of Spathoglottis plicata populations throughout its invasive range in Puerto Rico and Hawaii.
S1. Methods for estimating the fecundity values for the different size classes under field and experimental conditions.
To calculate the fecundities () that reflect the field conditions during this study (), that is, assuming that the damaged fruits (by the weevils) do not contribute to the production of recruits (and thus to λ) in any way, and that ants freely visit the inflorescences, we estimated as:
;
where is the number of recruits at time t + 1, is the total number of fruits with no weevil damage recorded at time t, is the mean number of fruits with no weevil damage produced per individual at stage in time t. Thus, the resulting values will represent the average number of recruits produced per individual at a given size stage taking in consideration the damage caused by weevils to flowers and fruits. In other words, this represents the fecundities under natural field conditions. We then incorporated these values to the size-structured transition matrices A(t0-t3).
To evaluate the effects to the population growth rates of S. plicata caused by damage due to florivory and oviposition by the weevils, we manipulated the fecundity values in the stage transition based on the reproductive effort data collected in this study (total number of flowers produced per individual). To estimate the population growth rate of S. plicata without weevil damage to flowers and fruits “WE” (Weevil Exclusion treatment) using the data gathered by Ackerman et al. (submitted), we estimated as:
;
where is the number of recruits at time t+1, is the number of fruits recorded at year t and that did not presented weevil damage, is the average fruit set derived by calculating the expected fruit set without weevil damage to flowers and fruits produced per individual at stage in time t, and is the total number of individuals of stage i recorded at time t. To calculate the expected fruit set without weevil damage to flowers and fruits from Ackerman et al. (submitted), we multiplied the total flowers produced at year t (reproductive effort) by the mean fruit set produced in “WE” (57.5%). This represents the expected average number of recruits produced per individual at a given size-stage assuming that only fruits with no weevil damage recorded through the study period contain viable seeds and this contribute to the population growth rate. The resulting fecundity values () were added into the transition matrices AWE (t0-t3).
S2. Methods for estimating the elements of the size-structured transition matrices.
To estimate the elements of the size-structured transition matrix, , where x is the fecundity values (depending on the level of weevil damage; see below), we used the stage-specific survival probability (), the probability of moving from one size stage to another ( for positive growth and for negative, retrogressive growth), the probability to flower in a given size class (), and the average number of recruits at t+1 produced per individual at a given size stage () from the data collected.
We then used the proposed stage-classified birth-flow formulation (with modifications) by Caswell (1989 in Caswell 2001) to calculate the matrix elements (following Brault and Caswell 1993) as:
the proportion of individuals from stage i that grow to a larger size-stage j given by
;
the proportion of individuals from stage i that regress to a smaller size-stage j given by
;
the proportion of individuals that remain in stage i given by
;
and the fecundities for the individuals of size class i given by
S3. Projection and elasticity matrices of Spathoglottis plicata derived from the size-stage transitions from the field data collected in this study, and fecundities estimated from the field data in this study, and from exclusion experiments (Excel file).
S4. Variation in survival and reproduction metrics of Spathoglottis plicata recorded during the demographic study period in the Río Abajo State Forest (Arecibo, Puerto Rico).The study period spanned four continuous years (2008–2011) and time transitions between censuses are denoted as C1–C4.
A-Survival probabilities at time t for each transition (t0-t3; broken lines), and the mean survival probabilities for all transitions (complete line) derived from the field data collected in this study. Bars show standard deviation of the proportions.
B-Flowering probabilities at time t for each transition (t0-t3; broken lines), and mean flowering probabilities for all transitions (complete line) derived from the field data collected in this study. Bars show standard deviation of the proportions.
C-Total flower production (reproductive effort) per size stage at time t for each transition (t0-t3; broken lines), and mean flowering probabilities for all transitions (complete line). Bars show the standard deviation of the mean.
D-Total fruit production per size stage at time t for each transition (t0-t3; broken lines), and mean flowering probabilities for all transitions (complete line). Bars show the ±SD of the mean.
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Falcón L. et al. Acquired interspecific interactions can influence population growth rates in non-indigenous plant species
S5: Summary statistics (mean SD) of demographic and reproductive parameters ofSpathoglottis plicata populations per island throughout its invasive range in Puerto Rico and Hawaii. Codes denote the abbreviations used in Figure 4 for the different sites; ABOout include plants in close proximity to our demographic study area sampled during t3in our demographic study. GPS points indicate the central area of individuals sampled for each population.aDamage not related to weevils.
Island / Year / Location / Code / N / Size / RE / Fruits / Fr-dam / RS / Weevils / GPSPuerto Rico
2011 / Arecibo / ABO(out) / 126 / – / 18.84 14.70 / 2.74 3.65 / 1.33 1.86 / 0.17 0.22 / P / 18.351457°, -66.685877°
2012 / El Yunque / EYQ / 51 / 77.3 33.6 / 15.49 14.23 / 3.80 5.33 / 0.72 1.96 / 0.33 0.41 / P / 18.304429°, -65.781463°
2012 / El Verde / EVE / 14 / 89.1 26.9 / 15.14 8.99 / 7.43 7.44 / 0.64 1.22 / 0.48 0.35 / P / 18.323563°, -65.820012°
2012 / Pico del Este / PDE / 14 / 61.0 32.4 / 12.14 16.69 / 4.14 3.06 / 0 / 0.61 0.35 / A / 18.270654°, -65.761471°
Kauai / (all populations) / KAU / 22 / 47.4 25.6 / 18.09 17.08 / 9.86 8.05 / 0 / 0.59 0.30
2010 / Lawai / 14 / 63.7 20.3 / 25.15 19.20 / 13.15 8.74 / 0 / 0.58 0.31 / A / 21.937520°, -159.468050°
2010 / Waimea / 8 / 29.7 19.8 / 8.38 3.81 / 5.63 3.38 / 0 / 0.65 0.29 / A / 22.013390°, -159.677480°
O’ahu / (all populations) / OAU / 66 / 48.3 33.4 / 12.33 9.05 / 5.80 5.00 / 0.08 0.32a / 0.51 0.27 / A
2010 / Hawai’i Loa / 7 / 36.9 21.2 / 17.57 17.45 / 5.86 5.49 / 0 / 0.47 0.28 / A / 21.299010°, -157.745910°
2010 / Kamehameha / 4 / 29.6 16.1 / 14.50 5.07 / 2.25 0.96 / 0 / 0.16 0.08 / A / 21.607760°, -157.923200°
2010 / Likelike / 2 / 23.1 19.5 / 16.50 9.19 / 13.0 9.90 / 0 / 0.73 0.19 / A / 21.409850°, -157.807280°
2010 / Mau’umae / 36 / 44.5 18.1 / 8.97 5.81 / 3.94 2.79 / 0.09 0.38a / 0.52 0.30 / A / 21.304183°, -157.779500°
2010 / Maunawili / 5 / 78.8 38.3 / 13.60 8.26 / 9.20 5.26 / 0 / 0.67 0.17 / A / 21.352740°, -157.768740°
2011 / Mau’umae / 12 / 77.1 41.9 / 17.42 9.09 / 9.92 6.22 / 0.17 0.39a / 0.56 0.18 / A / 21.308385°, -157.776670°
Big Island / 2010 / Keaau-Pahoa / BIS / 12 / 66.1 20.9 / 35.69 28.94 / 14.31 10.51 / 0 / 0.57 0.31 / A / 19.586610°, -155.011480°
Maui / (all populations) / MAU / 20 / 47.3 12.7 / 21.20 13.87 / 12.35 9.29 / 0.90 1.45a / 0.63 0.32 / A
2011 / Iao Valley / 4 / 47.5 7.8 / 21.0 19.77 / 10.75 10.81 / 0.50 1.00a / 0.55 0.34 / A / 20.882567°, -156.537850°
2011 / Kai Hele Ku / 11 / 47.9 8.2 / 24.0 12.96 / 12.91 8.38 / 1.45 1.69a / 0.61 0.34 / A / 20.851067°, -156.635650°
2011 / Kaupakalua / 5 / 46.6 17.2 / 15.20 11.56 / 12.40 11.99 / 0 / 0.76 0.28 / A / 20.885333°, -156.297633°
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