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Remote sensing imagery can provide critical information on the magnitude and extent of damage caused by forest pests and pathogens. However, monitoring short‐term changes in deciduous forest condition caused by defoliating insects is challenging and requires approaches that directly account for seasonal vegetation dynamics. We implemented a previously published harmonic modeling approach for forest condition monitoring in Google Earth Engine and systematically assessed the relative ability of condition change products generated using various model parameterizations for predicting pest abundances and defoliation during the 2016–2018 gypsy moth (Lymantria dispar) outbreak in southern New England. Our comparisons revealed that most models made reasonable predictions of changes in canopy condition and egg and larval abundances of L. dispar, indicating a strong correlation between our harmonic‐based estimates of condition change and defoliator activity. The greatest differences in predictive ability were in the spectral domain, with assessments based on Tasseled Cap Greenness, Simple Ratio, and the Enhanced Vegetation Index ranking among the top models, and the commonly used Normalized Difference Vegetation Index consistently exhibiting poorer performance. We also observed notable differences in the magnitude of scores for different baseline periods. Additionally, we found that Landsat‐based condition scores better explained larval abundance than egg mass counts, which have historically been used as a proxy for later‐season larval abundance, indicating that our remote sensing approach may be more accurate and cost‐effective for generating consistent retrospective assessments of L. dispar population abundance in addition to estimates of canopy damage. These findings provide important linkages between spectral changes detected using a harmonic modeling approach and biophysical aspects of defoliator activity, with potential to extend monitoring and prediction to regional or even continental scales.

Understanding the factors associated with declines of at-risk species is an important first step in setting management and recovery targets. This step can be challenging when multiple aspects of climate and land use are changing simultaneously, and any or all could be contributing to population declines. We analyzed population trends of monarch butterflies in western North America in relation to likely environmental drivers. Unlike the larger eastern monarch population, past analyses of western monarchs have only evaluated the importance of climate (i.e., not land use) factors as drivers of abundance. We used partial least squares regression (PLSR) to evaluate the potential importance of changes in land use and climate variables. Trends in western monarch abundance were more strongly associated with land use variables than climate variables. Conclusions about importance of climate and land use variables were robust to changes in PLSR model structure. However, individual variables were too collinear to unambiguously separate their effects. We compared these conclusions to the more widely used technique of multiple regression, followed by multi-model inference (MRMI). Naïve interpretation of MRMI results could be misleading, if collinearity were not taken into account. MRMI was also highly sensitive to variation in model construction. Our results suggest a two-pronged approach to monarch conservation, specifically, starting efforts now to restore habitat, while also using experiments to more clearly delineate separate effects of climate and land use factors. They also demonstrate the utility of PLSR, a technique that is growing in use but is still relatively under-appreciated in conservation biology.

Individual variation in movement can have important consequences for spatial population dynamics. For instance, individual variation increases leptokurtosis in dispersal distance, such that more individuals move very short and very long distances relative to a homogeneous population. We quantified individual variation in movement of the Baltimore checkerspot butterfly (Euphydryas phaeton) to investigate its importance for two conservation-related metrics: the expected dispersal distance and the critical minimum patch size, or the smallest area within which a population can persist based on loss due to emigration. All movement parameters showed among-individual variation, with the greatest variation in move lengths and time spent resting. Correlations in among-individual movement parameters indicated that some butterflies were generally more mobile than others. We incorporated empirically estimated movement and demographic parameters into two individual-based models (IBMs), one with homogeneity in movement among individuals, and one with heterogeneity in movement. As expected, individual variation in movement increased the leptokurtosis of lifetime movement distance; the maximum difference in distance moved was substantial (-850 m vs. -5800 m) and is likely of significance for conservation. Individual variation also affected the critical minimum patch size, but the difference (-0.7 ha vs. -0.5 ha) is unlikely to be ecologically significant. Notably, populations with individual variation had higher growth rates in small patches and lower growth rates in large patches, a logical consequence of increased leptokurtosis. Individual variation in movement is fairly straightforward to quantify using mixed effects models and is important for spatial population dynamics, thus we encourage its inclusion in studies of other systems.

Determining the minimum area required to sustain populations has a long history in theoretical and conservation biology. Correlative approaches are often used to estimate minimum area requirements (MARs) based on relationships between area and the population size required for persistence or between species’ traits and distribution patterns across landscapes. Mechanistic approaches to estimating MAR facilitate prediction across space and time but are few. We used a mechanistic MAR model to determine the critical minimum patch size (CMP) for the Baltimore checkerspot butterfly (Euphydryas phaeton), a locally abundant species in decline along its southern range, and sister to several federally listed species. Our CMP is based on principles of diffusion, where individuals in smaller patches encounter edges and leave with higher probability than those in larger patches, potentially before reproducing. We estimated a CMP for the Baltimore checkerspot of 0.7–1.5 ha, in accordance with trait-based MAR estimates. The diffusion rate on which we based this CMP was broadly similar when estimated at the landscape scale (comparing flight path vs. capture-mark-recapture data), and the estimated population growth rate was consistent with observed site trends. Our mechanistic approach to estimating MAR is appropriate for species whose movement follows a correlated random walk and may be useful where landscape-scale distributions are difficult to assess, but demographic and movement data are obtainable from a single site or the literature. Just as simple estimates of lambda are often used to assess population viability, the principles of diffusion and CMP could provide a starting place for estimating MAR for conservation. Requisitos Minimos de Area para una Mariposa en Riesgo con Base en su Movimiento y Demografia Resumen La determinacion del area minima requerida para sostener poblaciones tiene una larga historia en la biologia teorica y de la conservacion. Las estrategias de correlacion se usan continuamente para estimar los requisitos minimos de area (RMA) con base en las relaciones entre el area y el tamano de la poblacion requerido para su persistencia o entre las caracteristicas de las especies y los patrones de distribucion a lo largo de los paisajes. Las estrategias mecanicas para estimar los RMA facilitan la prediccion en el espacio y el tiempo pero son pocas. Usamos un modelo mecanico de RMA para determinar el tamano critico de fragmento (TCF) para la mariposa Euphydryas phaeton, una especie abundante localmente en declinacion a lo largo de su extension surena, y especie hermana de varias especies enlistadas a nivel federal. Nuestro TCF esta basado en los principios de difusion, en el que los individuos en pequenos fragmentos encuentran bordes y se dispersan con mayor probabilidad que aquellas en fragmentos mas grandes, potencialmente previo a la reproduccion. Estimamos un TCF de 0.7 – 1.5 ha para esta mariposa, de acuerdo con estimados de RMA con base en caracteristicas. La tasa de difusion sobre la que basamos este TCF fue similar en general cuando se estimo a escala de paisaje (comparar la ruta de vuelo versus datos de captura-marca-recaptura) y la tasa estimada de crecimiento de poblacion fue consistente con las tendencias observadas en el sitio. Nuestra estrategia mecanica para estimar los RMA es adecuada para especies cuyo movimiento sigue un camino aleatorio correlacionado y puede ser util donde las distribuciones paisaje-escala son dificiles de evaluar, pero los datos demograficos y de movimiento se pueden adquirir de un solo sitio o de la literatura. Asi como los estimados simples de lambda se usan frecuentemente para evaluar la viabilidad poblacional, los principios de difusion y el TCF puede proporcionar un punto de origen para estimar los RMA para la conservacion.

Summary 1. Human-induced land cover change threatens species diversity and ecosystem services. The rapid pace of current change makes predicting species’ declines imperative, but leaves little time for thorough study of all species. One solution is to make generalizations about species’ vulnerability to urbanization based on traits common among studied species in decline. 2. To date, most generalizations about traits associated with species’ declines in response to urbanization are based on presence or abundance, or detailed studies of a few species. If these generalizations broadly reflect responses to urbanization, they should hold across the mechanisms driving patterns of abundance, such as survival or reproduction. 3. Across 68 bird species in the north-eastern USA, we investigated how food preference, nest location, habitat preference, migration distance, number of broods, clutch size, body mass and an interaction between urbanization and these traits affected survival and reproduction. 4. Mass was the strongest predictor of survival, followed by number of broods, migration distance and nest location. Nest location was the strongest predictor of reproduction, followed by migration distance. No interaction between urbanization and species’ traits affected survival; however, differences in response to urbanization among species with different food preferences, migration distances, masses, nest locations and number of broods were important in predicting reproduction. 5. Synthesis and applications. We found that some traits influenced demographic rates even though they were not associated with urbanization; identifying differences in species’ baseline demographic rates, irrespective of urbanization, is needed to guide management objectives. Reproduction, but not survival, was influenced by urbanization, suggesting that management in our region of study should target increasing suitable nest sites and reducing nest predation. Determining traits associated with demographic rates and urbanization across broad geographic extents can provide new insights for species’ management and help guide conservation initiatives.

Examining seasonal mortality patterns can yield insights into the drivers of mortality and thus potential selection pressures acting on individuals in different environments. We compiled adult and juvenile mortality data from nine wild non-human primate taxa to investigate the role of seasonality in patterns of mortality and address the following questions: Is mortality highly seasonal across species? Does greater environmental seasonality lead to more seasonal mortality patterns? If mortality is seasonal, is it higher during wet seasons or during periods of food scarcity? and Do folivores show less seasonal mortality than frugivores? We found seasonal mortality patterns in five of nine taxa, and mortality was more often tied to wet seasons than food-scarce periods, a relationship that may be driven by disease. Controlling for phylogeny, we found a positive relationship between the degree of environmental seasonality and mortality, with folivores exhibiting more seasonal mortality than frugivores. These results suggest that mortality patterns are influenced both by diet and degree of environmental seasonality. Applied to a wider array of taxa, analyses of seasonal mortality patterns may aid understanding of life-history evolution and selection pressures acting across a broad spectrum of environments and spatial and temporal scales.

Tyrosine hydroxylase (TOH), the rate-limiting enzyme in catecholamine biosynthesis, is regulated by phosphorylation. Activation of histaminergic H 1 receptors on cultured bovine adrenal chromaffin cells stimulated a rapid increase in TOH phosphorylation (within 5 s) that was sustained for at least 5 min. The initial increase in TOH phosphorylation (up to 1 min) was essentially unchanged by the removal of extracellular Ca 2+ . In contrast, the H 1 -mediated response was abolished by preloading the cells with BAPTA acetoxymethyl ester (50 μM) and significantly reduced by prior exposure to caffeine (10 mM for 10 min) to deplete intracellular Ca 2+ . Tryptic-phosphopeptide analysis by HPLC revealed that the H 1 response in the presence or absence of extracellular Ca 2+ resulted in a major increase in the phosphorylation of Ser 19 with smaller increases in that of Ser 40 and Ser 31 . In contrast, although a brief stimulation with nicotine (30 μM for 60 s) also resulted in a major increase in Ser 19 phosphorylation, this response was abolished in the absence of extracellular Ca 2+ . These data indicate that the mobilization of intracellular Ca 2+ plays a crucial role in supporting H 1 -mediated TOH phosphorylation and may thus have a potentially important role in regulating catecholamine synthesis

The benefits of estrogen replacement therapy in postmenopausal women include increased quality of life, relief from specific symptoms, and the prevention of osteoporosis, genitourinary atrophy, and cardiovascular diseases. Despite these advantages, this therapy has been reported to be associated with an increased frequency of endometrial hyperplasia and adenocarcinoma. In order to evaluate a possible relationship between the histological findings and stroma-derived growth regulators, 19 endometrial samples obtained from women undergoing both percutaneous (n = 11) and oral (n = 8) steroid replacement therapy were processed for histological and immunocytochemical evaluation of estrogen receptor (Er), progesterone receptor (Pr), and epidermal growth factor receptor (EGFr). Transdermal estradiol was given for 21 days and 10 mg medroxyprogesterone acetate (MAP) were added to the last 12 days; conjugated equine estrogens were given for 21 days and 10 mg MAP added to the last 12 days. Endometrial samples were obtained between days 17-18 of the sixth month of therapy. Proliferative and hyperplastic endometria showed immunoreactivity against Er, Pr, and EGFr. Atrophic endometria were always negative by immunocytochemistry. Our results suggest: 1) a relationship between histological findings and the receptor examined; 2) a crucial role for EGF in the regulation of endometrial proliferation.