01878nas a2200133   4500008004100000245006700041210006600108300001400174490000700188520146200195100002001657700002001677856004701697       2005                        eng d00aEstimating postnatal dispersal: tracking the unseen dispersers0 aEstimating postnatal dispersal tracking the unseen dispersers  a1185-11900 v863 aPostnatal dispersal, defined as dispersal from the natal patch soon after reaching maturity, is common in a variety of insect species. Postnatal dispersal may increase connections among subpopulations and, thus, significantly affect local population dynamics in metapopulation and source-sink contexts. Yet most mark-recapture studies,of insects miss the postnatal dispersal phase because it comes soon after eclosion. Cephaloleia fenestrata (Chrysomelidae) is a specialist herbivore of the rolled leaves of Pleiostachya pruinosa (Marantaceae, common name "prayer plant"). Some P. pruinosa patches were flooded prior to the onset of this study, extirpating the majority of C. fenestrata in the flood zone and providing a natural experiment and an opportunity to observe recolonization dynamics. We built a spatially explicit population projection matrix model to simulate spatial population dynamics of C. fenestrata. The model was a poor fit to the empirical data. Adding postnatal dispersal to the model resulted in a much better model fit. This study suggests that 81% of C. fenestrata disperse from the natal site soon after eclosion. Model simulations indicated that postnatal dispersal increases the mean population size in the flood zone more than six-fold and the standard deviation more than three-fold. Herein we present an implicit method of estimating postnatal dispersal when marking animals before the postnatal dispersal phase is problematic.1 aJohnson, D., M.1 aHorvitz, C., C.  uhttps://cephaloleia.myspecies.info/node/2202357nas a2200121   4500008004100000245008900041210006900130300001400199490000700213520194800220100002002168856004702188       2005                        eng d00aMetapopulation models: An empirical test of model assumptions and evaluation methods0 aMetapopulation models An empirical test of model assumptions and  a3088-30980 v863 aPatch occupancy models provide a simple phenomenological approach to evaluating ecological questions on a metapopulation scale. In this study, I use and modify a patch occupancy model to evaluate the effects of synchronous extinctions correlated with flooding and patch-size-dependent migration on the regional dynamics of a neotropical beetle, Cephaloleia fenestrata. Various methods have been used to evaluate patch occupancy models. Previous authors most commonly have evaluated patch occupancy models by logistic regression of incidence functions. Likelihoods produced from regression methods, however, neglect autocorrelation in spatial occupancy patterns even though spatial autocorrelation is common in ecological data. In this study, I used a Monte Carlo method of model evaluation, which accounts for spatial autocorrelation. Results suggest that patches undergo synchronous extinctions correlated with flooding and this affects regional dynamics of C. fenestrata. Immigration probability positively correlated with patch size, and emigration probability negatively correlated with patch size, also affecting C. fenestrata regional dynamics. The patch occupancy pattern was positively spatially autocorrelated at only two of the sites, but was nearly significant at another. The logistic regression method was a reasonable alternative to the Monte Carlo method for model evaluation. Other model evaluation methods (fits to model development data, proportion of occupied patches, and turnover rates) were inconsistent (at best) quantitative measures of a model’s fit to independent data. When used to select among competing models, however, the fits to model development data were reasonably good indicators of fits to independent data. Given the increased complexity involved in using the Monte Carlo method, the simpler logistic regression method may be a preferable alternative, especially when spatial autocorrelation is minimal.1 aJohnson, D., M.  uhttps://cephaloleia.myspecies.info/node/2301976nas a2200133   4500008004100000245009800041210006900139300001200208490000700220520141100227653013701638100002001775856004701795       2004                        eng d00aLife history and demography of Cephaloleia fenestrata (Hispinae : Chrysomelidae : Coleoptera)0 aLife history and demography of Cephaloleia fenestrata Hispinae C  a352-3610 v363 aThe Neotropical beetle Cephaloleia fenestrata is a specialist herbivore on Pleiostachya pruinosa (Marantaceae) in upland and flood zone habitat of lowland tropical wet forest in Costa Rica. Cephaloleia fenestrata spends its entire life cycle on P pruinosa, feeding primarily in rolled young leaves as adults, feeding in the concavity of leaf petioles as larvae, and laying eggs and pupating on the leaf petioles. Egg development time is about average for Chrysomelidae, approximately ten days. Cephaloleia fenestrata larvae, like other rolled leaf hispines, have an extremely long development period (94 d) consisting of only two instars (compared to a range of three to six in other Chrysomelidae). The 30-day pupal stage is also long, but within the range of that observed in other Chrysomelidae. Adults live an average of six weeks. The generation time for C fenestrata is thus approximately six months. Male C fenestrata lived longer and had a higher capture probability than females. There was no difference between males and females in the movement probabilities between upland and flood zone habitat. Rolled P pruinosa leaves are both ephemeral (available to the beetles for approximately two days) and somewhat rare (I in ca 15 ramets has a rolled leaf). Adults must move from leaf to leaf ca 36 times during their average adult life span. Still, C fenestrata adults demonstrate high site fidelity.10acephaloleia fenestrata chrysomelidae hispinae marantaceae mark-recapture pleiostachya pruinosa heliconia beetles zingiberales plants1 aJohnson, D., M.  uhttps://cephaloleia.myspecies.info/node/2802593nas a2200133   4500008004100000245006800041210006600109300001400175490000700189520195100196653024502147100002002392856004702412       2004                        eng d00aSource-sink dynamics in a temporally, heterogeneous environment0 aSourcesink dynamics in a temporally heterogeneous environment  a2037-20450 v853 aIn traditional source-sink models, vital rates and movement probabilities are assumed to be temporally homogeneous. Numerous studies, however, have demonstrated that temporal heterogeneity is the rule rather than the exception in natural systems. A case of particular interest is an expanding and contracting population where determination. of source and sink populations is dependent on the timing and duration at which population growth rates are measured. Thus, ecologists have been perplexed about what is the proper scale to test for source-sink dynamics. In this study, I present a temporally variable source-sink dynamic driven by flooding disturbance. I measured population growth rates of an herbivorous neotropical rolled-leaf beetle, Cephaloleia fenestrata (Chrysomelidae), at different temporal scales in this expanding and contracting population. I demonstrate that flooding created a strong sink, but the system lacked source-sink dynamics during nonflood periods. The sink is caused by a flood-related sevenfold decrease in survival probability. There was no evidence for effects of flooding on recruitment. Migration was directional from the upland to the flood zone habitat, supporting the conclusion that the population in the flood zone is a sink. A Monte Carlo simulation demonstrated that whether the population in the flood zone is a sink, and the intensity of the sink, ultimately depend on the flooding frequency. Given an observed flood frequency of approximately once per year, the flood zone population was determined to be a Ion g-term sink. This study provides evidence of high temporal variability resulting in fluctuations in and out of a source-sink dynamic and implicates a causal factor (increased mortality due to flooding). These results illustrate the importance of. considering temporal variability in source-sink dynamics, and in choosing the proper temporal scale at which to test for source-sink dynamics.10acephaloleia fenestrata dispersal disturbance flooding mark-recapture pleiostachya pruinosa source-sink. dynamics survival temporal heterogeneity population-dynamics empirical-evidence quality metapopulation dispersal habitats forests models1 aJohnson, D., M.  uhttps://cephaloleia.myspecies.info/node/29