Stage-Structured Periodic Population Model for the Florida Leafwing

The Florida leafwing is an endemic butterfly which is distributed in South Florida and the lower Keys. Stage-structured population models are a useful tool for the management and conservation of Florida leafwing. In this work we use a discrete-time periodic control system for describing a leafwing population. One of the main differences between this model and classical stage-structured models is that in the current model we can alter the number of adults contributing to eggs production. This allows us to control the population. The solution of the problem is obtained using invariant formulations of positive periodic systems.Coll, C.; Horvitz, CC.; Mcelderry, R. (2012). Stage-Structured Periodic Population Model for the Florida Leafwing. International Journal of Complex Systems in Science. 2(1):1-5. http://hdl.handle.net/10251/80716S152

Conserving slow-growing, long-lived tree species: Input from the demography of a rare understory conifer, Taxus floridana

Although land preservation and promotion of successful regeneration are important conservation actions, their ability to increase population growth rates of slow-growing, long-lived trees is limited. We investigated the demography of Taxus floridana Nutt., a rare understory conifer, in three populations in different ravine forests spanning its entire geographic range along the Apalachicola River Bluffs in northern Florida (U.S.A.). We examined spatial and temporal patterns in demographic parameters and projected population growth rates by using four years of data on the recruitment and survival of seedlings and established stems, and on diameter growth from cross-sections of dead stems. All populations experienced a roughly 10-fold increase in seedling recruitment in 1996 compared with other years. The fates of seedlings and stems between 8 and 16 mm differed among populations. The fates of stems in two other size classes (the 2- to 4-mm class and the 4- to 8-mm class) differed among both populations and years. Individual stems in all populations exhibited similarly slow growth rates. Stochastic matrix models projected declines in all populations. Stochastic matrix analysis revealed the high elasticity of a measure of stochastic population growth rate to perturbations in the stasis of large reproductive stems for all populations. Additional analyses also indicated that occasional episodes of high recruitment do not greatly affect population growth rates. Conservation efforts directed at long-lived, slow-growing rare plants like Taxus floridana should both protect established reproductive individuals and further enhance survival of individuals in other life-history stages, such as juveniles, that often do not appear to contribute greatly to population growth rates

dorsalis

Data for Cephaloleia dorsalis (Chrysomelidae) from: Jack of all trades masters novel host plants: positive genetic correlations in specialist and generalist insect herbivores expanding their diets to novel hosts, Garcia-Robledo, Carlos, Horvitz, Caro

dilaticollis

Data for Cephaloleia dilaticollis from: Jack of all trades masters novel host plants: positive genetic correlations in specialist and generalist insect herbivores expanding their diets to novel hosts, Garcia-Robledo, Carlos, Horvitz, Caro

belti

Data for Cephaloleia belti (Chrysomelidae) from: Jack of all trades masters novel host plants: positive genetic correlations in specialist and generalist insect herbivores expanding their diets to novel hosts, Garcia-Robledo, Carlos, Horvitz, Caro

placida

Data for Cephaloleia placida (Chrysomelidae) from: Jack of all trades masters novel host plants: positive genetic correlations in specialist and generalist insect herbivores expanding their diets to novel hosts, Garcia-Robledo, Carlos, Horvitz, Caro

Maximum photosynthetic capacity

Contains measured rates of photosynthesis (leaf area based) for a subset of individuals in the experiment. The estimates of stomatal conductance are included but were not used because they were not taken at stomatal equilibrium

Growth and survival data

Contains total leaf area and survival (status) data for all individuals in the experiment. Leaf area was used to estimate growth rates. There is additional information on morphology, such as number of leaves, height, circumference. This information was not published in this paper