Ian Pearse is an Ecologist in the invasive species branch of the Fort Collins Science Center.
Ian Pearse is a research ecologist at the Fort Collins Science Center. Ian received a Ph.D. in Entomology from U.C. Davis in 2011. He has conducted research on plant-insect interactions and community ecology, focusing on ways to predict new interactions between introduced species such as plants and herbivorous insects. As part of the invasive species branch, Ian is applying that work to anticipate the impacts of destructive plant and insect invasions.
Education
- Ph.D. University of California, Davis, 2011
- B.S. University of Illinois, 2004
Professional Experience
- 2016 Postdoctoral work, University of California, Davis
- 2014-2015 Postdoctoral work, Illinois Natural History Survey
- 2012-2013 Postdoctoral work, Cornell University
Science and Products
Filter Total Items: 15
Data for a lab study of the effects of diet variability on the interactions between a Lepidopteran herbivore and its parasitoid
Data were collected from two laboratory rearing experiments conducted in 2018 of Trichoplusia ni caterpillars that had been parasitized by Copidosoma floridanum parasitoids. In the first experiment, parasitized caterpillars were fed artificial diets spiked with increasing concentrations of the phytochemical xanthotoxin in order to assess the effect of xanthotoxin on parasitoid success. In the seco
Greenhouse observations of plant herbivore interactions on Lepidium draba to test effects of ontogenic variability
Data were collected from an experimental greenhouse study in which Lepidium draba plants were grown from root cuttings to create plants at different ontogenic stages. Plants were arranged in mixed-age and single-age stands and exposed to the Lepidopteran herbivore, diamondback moth caterpillars. The success (biomass gain and surivival) of herbivores, the amount of feeding, and the growth of plants
Californian crop pests, pesticide applications, and phylogenetic information of crops
Information on pesticide applications, crop pests, and phylogenetic affinities between Californian crops and regional native plants were compiled. Data was collected to inform models of pesticide applications and host use of pests among California's 93 major crops. Pesticide data was assembled from California Department of Pesticide Regulation records, pest information was assembled from the Calif
Data on the impacts of garlic mustard from a weeding experiment in Pennsylvania 2006-2016
Data were collected on the abundance of plants in a 10-year weeding experiment of garlic mustard, located at Trillium Trails Park in Pennsylvania. Garlic mustard was weeded annually to suppress its abundance, and the impacts of garlic mustard were measured based on the response of the plant community to garlic mustard weeding. Because garlic mustard is known to suppress mycorrhizal fungi, the myco
Data on prairie dogs, plants, arthropod biomass, and birds for Thunder Basin, Wyoming in 2017
Data were collected in 2017 by researchers at the USGS, USDA-ARS, and University of Wyoming on the food webs of plants, prairie dogs, arthropods, and birds in the Thunder Basin National Grassland. Data were collected from 87 sites in order to parameterize a structural equation model linking prairie dog impacts to changes in vegetation, arthropods, and birds. Abiotic information such as topographic
Data on interannual seed set variation, weather, and reproductive traits for global plants
Data were collected on seed production dynamics of long-lived plants, reproductive plant traits of those plant species, and weather variability for sites where those species live. Data include the coefficient of variation in seed production over time, the variation (coefficient of variation or standard deviation) in weather over years, and reproductive traits such as pollination mode and seed disp
Data on cone production in pinyon pine in the Southwestern USA from 2003-2016
Data were collected on pinyon pine cone production using the cone scar method (Redmond et al 2016 Forest Ecology and Management) from 2003-2016 among sites in the Southwest USA. Long-term weather data (Vapor Pressure Deficits and monsoonality) were associated with cone scar data to assess weather-correlates of cone production.
Data on gall wasp abundance and biomass on valley oak and blue oak trees in California
Gall abundance and biomass was recorded on marked valley oak and blue oak individuals throughout California. Galls, mostly caused by cynipid gall wasps, were identified to species. Sampling effort per tree was recorded as the number of leaves searched for gall wasps. Leaves were taken from two branches per tree using pole pruners, and total galls per tree were summed in each observation. Annual ob
Long term cone production of white spruce throughout boreal forests in North America
Data were compiled on the seed production of white spruce in order to assess the long-term trends in seed production over the past 60 years in North American boreal forests. Data on cone production was merged with annual weather, teleconnection indices such as ENSO, and historical fires in boreal forests.
Data on interannual variability of seed production, nutrient, and weather for 219 plant species
We calculated estimates describing interannual variation in seed production for series of long-term seed or fruit production in 219 plant species. For each plant species, we compiled estimates of foliar nutrient concentrations as well as productivity and weather at the site of observation. Data was compiled in order to test whether interannual variation in seed production was greater in species wi
Croton setiger predators, herbivores, and damage collected in California 2013-2014
A pollen addition experiment was conducted on the leaves of Croton setiger, a Californian forb. Pollen was added to leaves of randomly selected plants, and control plants had no pollen added. Over 2013 and 2014 the number of predatory and herbivorous insects were counted on each plant, and the number of damaged leaves and plant size were measured.
Measurements of plant abundance with reference to dominant plants in Illinois wetlands
Data were collected on plant abundance in Illinois with the goal of determining correlations between the abundance of dominant plant taxa and other plant species.
Filter Total Items: 33
Long-term trends in midwestern milkweed abundances and their relevance to monarch butterfly declines
Declines in monarch butterfly populations have prompted investigation into the sensitivity of their milkweed host plants to land-use change. Documented declines in milkweed abundance in croplands have spurred efforts to promote milkweeds in other habitats. Nevertheless, our current understanding of milkweed populations is poor. We used a long-term plant survey from Illinois to evaluate whether tre
Entrapped carrion increases indirect plant resistance and intra‐guild predation on a sticky tarweed
Many plants employ indirect defenses against herbivores; often plants provide a shelter or nutritional resource to predators, increasing predator abundance, and lessening herbivory to the plant. Often, predators on the same plant represent different life stages and different species. In these situations intraguild predation (IGP) may occur and may decrease the efficacy of that defense. Recently, s
Variation in plant defense suppresses herbivore performance
Defensive variability of crops and natural systems can alter herbivore communities and reduce herbivory. However, it is still unknown how defense variability translates into herbivore suppression. Nonlinear averaging and constraints in physiological tracking (also more generally called time-dependent effects) are the two mechanisms by which defense variability might impact herbivores. We conducted
The relationship between invader abundance and impact
The impacts of invasive species generally increase with their abundance, but the form of invader abundance–impact relationships remain poorly described. We highlight the utility of abundance–impact curves for three questions. First, abundance–impact relationships can clarify whether prevention and management should focus on the species likely to become abundant or those likely to cause large impac
Seasonal assembly of arthropod communities on milkweeds experiencing simulated herbivory
The seasonal assembly of arthropod communities is shaped by biotic and abiotic aspects of the habitat that limit the appearance or activity phenology of potential community members. In addition, previous interactions within the community, such as herbivore-induced plant defensive responses, aggregation, and predator avoidance likely affect the assembly of arthropod communities on individual plants
Non-native plants have greater impacts because of differing per-capita effects and non-linear abundance-impact curves
Invasive, non-native species can have tremendous impacts on biotic communities, where they reduce the abundance and diversity of local species. However, it remains unclear whether impacts of non-native species arise from their high abundance or whether each non-native individual has a disproportionate impact – i.e., a higher per-capita effect – on co-occurring species compared to impacts by native
The development and delivery of species distribution models to inform decision-making
Information on where species occur is central to conservation and management decisions, but knowledge of distributions can be coarse or incomplete. Species distribution models provide a tool for mapping suitable habitat, and can produce credible, defensible, and repeatable predictive information with which to inform decisions. However, these models are sensitive to data inputs and methodological c
From Manitoba to Texas: A study of the population genetic structure of bur oak (Quercus macrocarpa)
In the taxonomic world, the oaks are known as a rambunctious group, notorious for hybridizing. In this report, we present preliminary information to address the question of how much hybridization is occurring between bur oak and white oaks with which it is sympatric, through rangewide sampling of bur oak and five co-occurring species: white oak (Q. alba L.), swamp white oak (Q. bicolor Willd.), po
Climate teleconnections synchronize Picea glauca masting and fire disturbance: Evidence for a fire‐related form of environmental prediction
Synchronous pulses of seed masting and natural disturbance have positive feedbacks on the reproduction of masting species in disturbance‐prone ecosystems. We test the hypotheses that disturbances and proximate causes of masting are correlated, and that their large‐scale synchrony is driven by similar climate teleconnection patterns at both inter‐annual and decadal time scales.Hypotheses were teste
Mast seeding patterns are asynchronous at a continental scale
Resource pulses are short duration, high magnitude, rare events that drive the dynamics of both plant and animal populations and communities1. Mast seeding is perhaps the most common type of resource pulse occurring in terrestrial ecosystems2, is characterized by the synchronous and highly variable production of seed crops by a population of perennial plants3,4, and is widespread both taxonomicall
Aridity drives spatiotemporal patterns of masting across the latitudinal range of a dryland conifer
Masting, or the synchronous and irregular production of seed crops, is controlled by environmental conditions and resource budgets. Increasing temperatures and shifting precipitation regimes may alter the frequency and magnitude of masting, especially in species that experience chronic resource stress. Yet the effects of a changing climate on seed production are unlikely to be uniform across popul
Pre-USGS Publications
Pearse, I.S., Koenig, W.D., Kelly, D. 2016. Mechanisms of mast seeding: resources, weather, cues, and selection. The New Phytologist 212: 546-562
http://onlinelibrary.wiley.com/doi/10.1111/nph.14114/full
http://onlinelibrary.wiley.com/doi/10.1111/nph.14114/full
Mescher, M.C. and Pearse, I.S. 2016. Communicative interactions involving plants: information, evolution, and ecology Current Opinion in Plant Biology 32: 69-76. http://www.sciencedirect.com/science/article/pii/S136952661630098X
Krimmel, B.A., Pearse, I.S. 2016. Tolerance and phenological avoidance of herbivory in tarweed species. Ecology 97: 1357-1363. http://onlinelibrary.wiley.com/doi/10.1890/15-1454.1/full
Pesendorfer, M., Koenig, W.D., Pearse, I.S., Knops, J.M.H., Funk, K. 2016. Individual resource limitation combined with population-wide pollen availability drives masting in the valley oak (Quercus lobata). Journal of Ecology 104: 637-645.
http://onlinelibrary.wiley.com/doi/10.1111/1365-2745.12554/pdf
http://onlinelibrary.wiley.com/doi/10.1111/1365-2745.12554/pdf
Moriera, X., Sampedro, L., Zas, R., Pearse, I.S. 2016. Defensive Traits in Young Pine Trees Cluster into Two Divergent Syndromes Related to Early Growth Rate. PlosOne. 0152537.
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0152537
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0152537
Koenig, W.D., Alejano, R., Dolores Carbonero, M., Fernández-Rebollo, P., Knops, J.M.H, Maranon, T., Padilla-Diaz, C.M., Pearse, I.S., Perez-Ramon, I.M., Pesendorfer, M.B. 2016. Is the relationship between mast‐seeding and weather in oaks related to their life‐history or phylogeny? Ecology 97: 2603-2615. http://onlinelibrary.wiley.com/doi/10.1002/ecy.1490/full
Yguel, B., Jactel, H., Pearse, I.S., Moen, D., Winter, M., Hortal, J., Helmus, M., Kühn, I., Pavoine, S., Purschke, O., Weiher, E., Violle, C., Ozinga, W., Braendle M., Bartish I., Prinzing, A. 2016. The Evolutionary Legacy of Diversification Predicts Ecosystem Function. The American Naturalist. http://www.journals.uchicago.edu/doi/abs/10.1086/687964
Pearse, I.S., Koenig, W.D., Funk, K.A., Presendorfer, M.B. 2015. Pollen limitation and flower abortion in a wind-pollinated, masting tree. Ecology 96: 587-593
http://onlinelibrary.wiley.com/doi/10.1890/14-0297.1/ful
http://onlinelibrary.wiley.com/doi/10.1890/14-0297.1/ful
Koenig, W.D., Knops, J.M.H., Carmen, W.J., Pearse, I.S. 2015. What drives masting? The phenological synchrony hypothesis. Ecology 96: 184-192. http://onlinelibrary.wiley.com/doi/10.1890/14-0819.1/full
McMahon, D., Pearse, I.S., Koenig, W.D., Walters, E.L. 2015. Oak community shift and woodpecker population increase over three decades in California woodland. Canadian Journal of Forest Research. http://www.nrcresearchpress.com/doi/abs/10.1139/cjfr-2015-0035#.V__Zq_krJ9M
LoPresti, E.F., Pearse, I.S., Charles, G.K. 2015. A plant siren song: columbines provision mutualist arthropods by attracting and killing passerby insects. Ecology (featured in Science and Discover Magazine)
http://onlinelibrary.wiley.com/doi/10.1890/15-0342.1/full
http://onlinelibrary.wiley.com/doi/10.1890/15-0342.1/full
Pearse, I.S., Altermatt, F. 2015. Out of sample predictions from plant-insect food webs: robustness to missing and erroneous trophic interaction records. Ecological Applications. http://onlinelibrary.wiley.com/doi/10.1890/14-1463.1/full
Pearse, I.S., Baty, J.H., Herrmann, D.L., Sage, R., Koenig, W.D. 2015. Leaf phenology mediates provenance differences in herbivore populations on valley oaks in a common garden. Ecological Entomology. http://onlinelibrary.wiley.com/doi/10.1111/een.12219/full
Hughes, K.A., Pearse, I.S., Gof-Tizsa, P., Karban, R. 2015. Individual-level differences in generalist caterpillar responses to a plant-plant signal. Ecological Entomology. http://onlinelibrary.wiley.com/doi/10.1111/een.12224/full
Pearse, I.S., Funk, K.A., Kraft, T.S., Koenig, W.D. 2015. Lagged effects of early‑season herbivores on valley oak fecundity. Oecologia 178: 361-368. http://link.springer.com/article/10.1007/s00442-014-3193-2
Petchey, O.L., Pontarp, M., Massie, T.N., Kéfi, S., Ozgul, A., Weilenmann, M., Palamara, G.C., Altermatt, F., Matthews, B.J., Levine, J.M., Childs, D.Z., McGill, B.J., Schaepman, M.E., Schmid, B., Spaak, P., Beckerman, A.P., Pennekamp, F., Pearse, I.S. 2015. The Ecological Forecast Horizon, and examples of its uses and determinants. Ecology Letters. http://onlinelibrary.wiley.com/doi/10.1111/ele.12443/full
Pearse, I.S., Hipp, A.L. 2014. Native plant diversity increases herbivory to non-natives. Proceedings of the Royal Society – B 281: 20141841. http://rspb.royalsocietypublishing.org/content/281/1794/20141841.short
Desurmont, G., Pearse, I.S. Alien plants versus alien herbivores: does it matter who is non-native in a novel trophic interaction? Current Opinion in Insect Science 2: 20-25. http://www.sciencedirect.com/science/article/pii/S221457451400035
Krimmel, B.A., Pearse, I.S. 2014. Generalist and sticky plant specialist predators suppress herbivores on a sticky plant. Arthropod Plant Interactions 8: 403-410. http://link.springer.com/article/10.1007/s11829-014-9318-z
Pearse, I.S., Cobb, R.C., Karban, R. 2014. The phenology substrate match hypothesis explains decomposition rates of evergreen and deciduous oak leaves. Journal of Ecology 102: 28-35. http://onlinelibrary.wiley.com/doi/10.1111/1365-2745.12182/full
Koenig, W.D., Walters, E.L., Pearse, I.S., Knops, J.M.H. 2014. Serotiny in California oaks. Madroño 61(2): 151-158. http://www.bioone.org/doi/full/10.3120/0024-9637-61.2.151
Pearse, IS, Koenig, WD, Knops, JMH. 2014. Cues versus proximate drivers: testing the mechanism behind masting behavior. Oikos 123: 179-184 http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0706.2013.00608.x/full
Karban, R., Huntzinger, M., Pearse, I.S. 2014. How to Do Ecology: A Concise Handbook, 2nd edition. Princeton University Press, Princeton. http://press.princeton.edu/titles/10284.html
Pearse, I.S., Bastow, J.L., Tsang, A. 2014. Radish introduction affects soil biota but has a positive impact on the growth of a native plant. Oecologia 174: 471-478. http://link.springer.com/article/10.1007/s00442-013-2779-4
Pearse, I.S., Griswold, S., Pizarro, D., Koenig, W.D. 2014. Stage and size structure of three species of oaks in central coastal California. Madroño 61(1): 1-8. http://www.bioone.org/doi/abs/10.3120/0024-9637-61.1.1
Pearse, I.S., Gee, W.S., Beck, J.J. 2013. Headspace volatiles from 52 oak species advertise induction, species identity, and evolution, but not defense. Journal of Chemical Ecology 39: 90-100. http://link.springer.com/article/10.1007/s10886-012-0224-5
Pearse, I.S. and Altermatt, F. 2013. Extinction cascades partially estimate observed herbivore losses in a Lepidoptera-plant food web. Ecology 94(8): 1785-1794 (Cover article). http://onlinelibrary.wiley.com/doi/10.1890/12-1075.1/full
Pearse, I.S., Hughes, K., Shiojiri, K., Ishizaki, S., Karban, R. 2013. Interplant volatile signaling in willows: revisiting the original talking trees. Oecologia 172: 869-875 (Cover article). http://link.springer.com/article/10.1007/s00442-013-2610-2
Pearse, I.S. and Karban, R. 2013. Leaf drop affects herbivory in oaks. Oecologia 173: 925-932. http://link.springer.com/article/10.1007/s00442-013-2689-5
Pearse, I.S., Harris, D.J., Karban, R., Sih, A. 2013.Predicting novel herbivore-plant interactions. Oikos 122: 1554-1564. http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0706.2013.00527.x/full
Pearse, I.S. and Altermatt F. 2013. Predicting novel trophic interactions in a non-native world. Ecology Letters 16: 1088-1094. http://onlinelibrary.wiley.com/doi/10.1111/ele.12143/full
Krimmel, B.A. and Pearse, I.S. 2013. Sticky plants trap invertebrate carrion to enhance indirect defense. Ecology Letters. 16: 219-224 (featured in Nature). http://onlinelibrary.wiley.com/doi/10.1111/ele.12032/full
Savchenko, T., Pearse, I.S., Karban, R., DeHesh, K. 2013. Insect feeding habits determine the composition of hydroperoxide lyase-derived metabolites. The Plant Journal 73: 653-662. http://onlinelibrary.wiley.com/doi/10.1111/tpj.12064/full
Pearse, I.S., Karban, R. 2013. Do plant-plant signals mediate herbivory consistently in multiple taxa and ecological contexts? Journal of Plant Interactions 8(3): 203-206. http://www.tandfonline.com/doi/abs/10.1080/17429145.2013.765511
Pearse, I.S. and Hipp, A.L. 2012. Global patterns of leaf defenses in oak species. Evolution. 66(7): 2272-2286. http://onlinelibrary.wiley.com/doi/10.1111/j.1558-5646.2012.01591.x/full
Herrmann, D.L., Pearse, I.S., Baty, J.H. 2012. Drivers of specialist herbivore diversity across 10 cities. Landscape and Urban Planning 108: 123-130. http://www.sciencedirect.com/science/article/pii/S0169204612002617
Pearse, I.S., Parensky, L.M., Yang, L.H., Stanton, M.L., Karban, R., Bhattacharyya, L., Dove, K., Higgins, A., Kamaroff, C., Kirk, T., Knight, C., Koch, R., Rollins, H., Tanner, K., Cox, R. 2012. Complex consequences of herbivory and interplant cues in three annual plants. PlosOne 7(5): e38105. http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0038105
Pearse, I.S. and Baty, J.H. 2012. The predictability of traits and ecological interactions on 17 different crosses of hybrid oaks. Oecologia 169: 489-497. http://link.springer.com/article/10.1007/s00442-011-2216-5
Pearse, I.S. 2012. The role of leaf defensive traits in oaks on the preference and performance of a polyphagous herbivore, Orgyia vetusta. Ecological Entomology 36(5): 635-642. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2311.2011.01308.x/full
Altermatt, F., Pearse, I.S. 2011. Similarity and specialization of the larval versus adult diets of European butterflies and moths. The American Naturalist 178(3): 372-378. http://www.jstor.org/stable/10.1086/661248?seq=1#page_scan_tab_contents
Joseph, M., Gentles, M., Pearse, I.S. 2011. The parasitoid community of Andricus quercuscalifornicus (Hymenoptera: Cynipidae) is associated with gall size and host phenology. Biodiversity and Conservation 20: 203-216.
http://link.springer.com/article/10.1007/s10531-010-9956-0
http://link.springer.com/article/10.1007/s10531-010-9956-0
Pearse I.S. 2011. Novel herbivore-plant interactions: Evidence from non-native oaks (Dissertation) U. California – Davis. http://gradworks.umi.com/34/99/3499479.html
Pearse, I.S. 2010. Bird rookeries have different effects on different feeding guilds of herbivores and alter the feeding behavior of a common caterpillar. Arthropod Plant Interactions 4: 189-195. http://link.springer.com/article/10.1007/s11829-010-9098-z
Karban, R., C. Karban, Huntzinger, M., Pearse, I., Crutsinger, G. 2010. Diet mixing enhances the performance of a generalist caterpillar, Platyprepia virginalis. Ecological Entomology 35(1): 92-99. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2311.2009.01162.x/full
Pearse, I.S. and A.L. Hipp. 2009. Phylogenetic and trait similarity to a native species predict herbivory on non-native oaks. Proceedings of the National Academy of Sciences of the United States of America 106(43): 18097-18102. (Cover article)
http://www.pnas.org/content/106/43/18097.short
http://www.pnas.org/content/106/43/18097.short
Pearse, I, Zhu, Y, Murray, E, Dudeja, P, Ramaswamy, K, Malakooti, J. 2007. Sp1 and Sp3 control constitutive expression of the human NHE2 promoter by interactions with the proximal promoter and the transcription initiation site. Biochemical Journal 407: 101-111. http://www.biochemj.org/content/407/1/101.abstract
Pearse, IS, Krügel, T, Baldwin, IS. 2006. Innovation in anti-herbivore defense systems during neopolyploidy - the functional consequences of instantaneous speciation. The Plant Journal 47: 196-210. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-313X.2006.02776.x/full
Pearse, I.S., Heath, K.D., Cheeseman, J.M. 2006. Biochemical and ecological characterization of two peroxidase isoenzymes from the mangrove, Rhizophora mangle. Plant, Cell and Environment 28: 612-622 (Cover article).
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-3040.2005.01307.x/full
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-3040.2005.01307.x/full
Science and Products
- Data
Filter Total Items: 15
Data for a lab study of the effects of diet variability on the interactions between a Lepidopteran herbivore and its parasitoid
Data were collected from two laboratory rearing experiments conducted in 2018 of Trichoplusia ni caterpillars that had been parasitized by Copidosoma floridanum parasitoids. In the first experiment, parasitized caterpillars were fed artificial diets spiked with increasing concentrations of the phytochemical xanthotoxin in order to assess the effect of xanthotoxin on parasitoid success. In the secoGreenhouse observations of plant herbivore interactions on Lepidium draba to test effects of ontogenic variability
Data were collected from an experimental greenhouse study in which Lepidium draba plants were grown from root cuttings to create plants at different ontogenic stages. Plants were arranged in mixed-age and single-age stands and exposed to the Lepidopteran herbivore, diamondback moth caterpillars. The success (biomass gain and surivival) of herbivores, the amount of feeding, and the growth of plantsCalifornian crop pests, pesticide applications, and phylogenetic information of crops
Information on pesticide applications, crop pests, and phylogenetic affinities between Californian crops and regional native plants were compiled. Data was collected to inform models of pesticide applications and host use of pests among California's 93 major crops. Pesticide data was assembled from California Department of Pesticide Regulation records, pest information was assembled from the CalifData on the impacts of garlic mustard from a weeding experiment in Pennsylvania 2006-2016
Data were collected on the abundance of plants in a 10-year weeding experiment of garlic mustard, located at Trillium Trails Park in Pennsylvania. Garlic mustard was weeded annually to suppress its abundance, and the impacts of garlic mustard were measured based on the response of the plant community to garlic mustard weeding. Because garlic mustard is known to suppress mycorrhizal fungi, the mycoData on prairie dogs, plants, arthropod biomass, and birds for Thunder Basin, Wyoming in 2017
Data were collected in 2017 by researchers at the USGS, USDA-ARS, and University of Wyoming on the food webs of plants, prairie dogs, arthropods, and birds in the Thunder Basin National Grassland. Data were collected from 87 sites in order to parameterize a structural equation model linking prairie dog impacts to changes in vegetation, arthropods, and birds. Abiotic information such as topographicData on interannual seed set variation, weather, and reproductive traits for global plants
Data were collected on seed production dynamics of long-lived plants, reproductive plant traits of those plant species, and weather variability for sites where those species live. Data include the coefficient of variation in seed production over time, the variation (coefficient of variation or standard deviation) in weather over years, and reproductive traits such as pollination mode and seed dispData on cone production in pinyon pine in the Southwestern USA from 2003-2016
Data were collected on pinyon pine cone production using the cone scar method (Redmond et al 2016 Forest Ecology and Management) from 2003-2016 among sites in the Southwest USA. Long-term weather data (Vapor Pressure Deficits and monsoonality) were associated with cone scar data to assess weather-correlates of cone production.Data on gall wasp abundance and biomass on valley oak and blue oak trees in California
Gall abundance and biomass was recorded on marked valley oak and blue oak individuals throughout California. Galls, mostly caused by cynipid gall wasps, were identified to species. Sampling effort per tree was recorded as the number of leaves searched for gall wasps. Leaves were taken from two branches per tree using pole pruners, and total galls per tree were summed in each observation. Annual obLong term cone production of white spruce throughout boreal forests in North America
Data were compiled on the seed production of white spruce in order to assess the long-term trends in seed production over the past 60 years in North American boreal forests. Data on cone production was merged with annual weather, teleconnection indices such as ENSO, and historical fires in boreal forests.Data on interannual variability of seed production, nutrient, and weather for 219 plant species
We calculated estimates describing interannual variation in seed production for series of long-term seed or fruit production in 219 plant species. For each plant species, we compiled estimates of foliar nutrient concentrations as well as productivity and weather at the site of observation. Data was compiled in order to test whether interannual variation in seed production was greater in species wiCroton setiger predators, herbivores, and damage collected in California 2013-2014
A pollen addition experiment was conducted on the leaves of Croton setiger, a Californian forb. Pollen was added to leaves of randomly selected plants, and control plants had no pollen added. Over 2013 and 2014 the number of predatory and herbivorous insects were counted on each plant, and the number of damaged leaves and plant size were measured.Measurements of plant abundance with reference to dominant plants in Illinois wetlands
Data were collected on plant abundance in Illinois with the goal of determining correlations between the abundance of dominant plant taxa and other plant species. - Publications
Filter Total Items: 33
Long-term trends in midwestern milkweed abundances and their relevance to monarch butterfly declines
Declines in monarch butterfly populations have prompted investigation into the sensitivity of their milkweed host plants to land-use change. Documented declines in milkweed abundance in croplands have spurred efforts to promote milkweeds in other habitats. Nevertheless, our current understanding of milkweed populations is poor. We used a long-term plant survey from Illinois to evaluate whether treEntrapped carrion increases indirect plant resistance and intra‐guild predation on a sticky tarweed
Many plants employ indirect defenses against herbivores; often plants provide a shelter or nutritional resource to predators, increasing predator abundance, and lessening herbivory to the plant. Often, predators on the same plant represent different life stages and different species. In these situations intraguild predation (IGP) may occur and may decrease the efficacy of that defense. Recently, sVariation in plant defense suppresses herbivore performance
Defensive variability of crops and natural systems can alter herbivore communities and reduce herbivory. However, it is still unknown how defense variability translates into herbivore suppression. Nonlinear averaging and constraints in physiological tracking (also more generally called time-dependent effects) are the two mechanisms by which defense variability might impact herbivores. We conductedThe relationship between invader abundance and impact
The impacts of invasive species generally increase with their abundance, but the form of invader abundance–impact relationships remain poorly described. We highlight the utility of abundance–impact curves for three questions. First, abundance–impact relationships can clarify whether prevention and management should focus on the species likely to become abundant or those likely to cause large impacSeasonal assembly of arthropod communities on milkweeds experiencing simulated herbivory
The seasonal assembly of arthropod communities is shaped by biotic and abiotic aspects of the habitat that limit the appearance or activity phenology of potential community members. In addition, previous interactions within the community, such as herbivore-induced plant defensive responses, aggregation, and predator avoidance likely affect the assembly of arthropod communities on individual plantsNon-native plants have greater impacts because of differing per-capita effects and non-linear abundance-impact curves
Invasive, non-native species can have tremendous impacts on biotic communities, where they reduce the abundance and diversity of local species. However, it remains unclear whether impacts of non-native species arise from their high abundance or whether each non-native individual has a disproportionate impact – i.e., a higher per-capita effect – on co-occurring species compared to impacts by nativeThe development and delivery of species distribution models to inform decision-making
Information on where species occur is central to conservation and management decisions, but knowledge of distributions can be coarse or incomplete. Species distribution models provide a tool for mapping suitable habitat, and can produce credible, defensible, and repeatable predictive information with which to inform decisions. However, these models are sensitive to data inputs and methodological cFrom Manitoba to Texas: A study of the population genetic structure of bur oak (Quercus macrocarpa)
In the taxonomic world, the oaks are known as a rambunctious group, notorious for hybridizing. In this report, we present preliminary information to address the question of how much hybridization is occurring between bur oak and white oaks with which it is sympatric, through rangewide sampling of bur oak and five co-occurring species: white oak (Q. alba L.), swamp white oak (Q. bicolor Willd.), poClimate teleconnections synchronize Picea glauca masting and fire disturbance: Evidence for a fire‐related form of environmental prediction
Synchronous pulses of seed masting and natural disturbance have positive feedbacks on the reproduction of masting species in disturbance‐prone ecosystems. We test the hypotheses that disturbances and proximate causes of masting are correlated, and that their large‐scale synchrony is driven by similar climate teleconnection patterns at both inter‐annual and decadal time scales.Hypotheses were testeMast seeding patterns are asynchronous at a continental scale
Resource pulses are short duration, high magnitude, rare events that drive the dynamics of both plant and animal populations and communities1. Mast seeding is perhaps the most common type of resource pulse occurring in terrestrial ecosystems2, is characterized by the synchronous and highly variable production of seed crops by a population of perennial plants3,4, and is widespread both taxonomicallAridity drives spatiotemporal patterns of masting across the latitudinal range of a dryland conifer
Masting, or the synchronous and irregular production of seed crops, is controlled by environmental conditions and resource budgets. Increasing temperatures and shifting precipitation regimes may alter the frequency and magnitude of masting, especially in species that experience chronic resource stress. Yet the effects of a changing climate on seed production are unlikely to be uniform across populPre-USGS Publications
Pearse, I.S., Koenig, W.D., Kelly, D. 2016. Mechanisms of mast seeding: resources, weather, cues, and selection. The New Phytologist 212: 546-562
http://onlinelibrary.wiley.com/doi/10.1111/nph.14114/fullMescher, M.C. and Pearse, I.S. 2016. Communicative interactions involving plants: information, evolution, and ecology Current Opinion in Plant Biology 32: 69-76. http://www.sciencedirect.com/science/article/pii/S136952661630098XKrimmel, B.A., Pearse, I.S. 2016. Tolerance and phenological avoidance of herbivory in tarweed species. Ecology 97: 1357-1363. http://onlinelibrary.wiley.com/doi/10.1890/15-1454.1/fullPesendorfer, M., Koenig, W.D., Pearse, I.S., Knops, J.M.H., Funk, K. 2016. Individual resource limitation combined with population-wide pollen availability drives masting in the valley oak (Quercus lobata). Journal of Ecology 104: 637-645.
http://onlinelibrary.wiley.com/doi/10.1111/1365-2745.12554/pdfMoriera, X., Sampedro, L., Zas, R., Pearse, I.S. 2016. Defensive Traits in Young Pine Trees Cluster into Two Divergent Syndromes Related to Early Growth Rate. PlosOne. 0152537.
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0152537Koenig, W.D., Alejano, R., Dolores Carbonero, M., Fernández-Rebollo, P., Knops, J.M.H, Maranon, T., Padilla-Diaz, C.M., Pearse, I.S., Perez-Ramon, I.M., Pesendorfer, M.B. 2016. Is the relationship between mast‐seeding and weather in oaks related to their life‐history or phylogeny? Ecology 97: 2603-2615. http://onlinelibrary.wiley.com/doi/10.1002/ecy.1490/fullYguel, B., Jactel, H., Pearse, I.S., Moen, D., Winter, M., Hortal, J., Helmus, M., Kühn, I., Pavoine, S., Purschke, O., Weiher, E., Violle, C., Ozinga, W., Braendle M., Bartish I., Prinzing, A. 2016. The Evolutionary Legacy of Diversification Predicts Ecosystem Function. The American Naturalist. http://www.journals.uchicago.edu/doi/abs/10.1086/687964Pearse, I.S., Koenig, W.D., Funk, K.A., Presendorfer, M.B. 2015. Pollen limitation and flower abortion in a wind-pollinated, masting tree. Ecology 96: 587-593
http://onlinelibrary.wiley.com/doi/10.1890/14-0297.1/fulKoenig, W.D., Knops, J.M.H., Carmen, W.J., Pearse, I.S. 2015. What drives masting? The phenological synchrony hypothesis. Ecology 96: 184-192. http://onlinelibrary.wiley.com/doi/10.1890/14-0819.1/fullMcMahon, D., Pearse, I.S., Koenig, W.D., Walters, E.L. 2015. Oak community shift and woodpecker population increase over three decades in California woodland. Canadian Journal of Forest Research. http://www.nrcresearchpress.com/doi/abs/10.1139/cjfr-2015-0035#.V__Zq_krJ9MLoPresti, E.F., Pearse, I.S., Charles, G.K. 2015. A plant siren song: columbines provision mutualist arthropods by attracting and killing passerby insects. Ecology (featured in Science and Discover Magazine)
http://onlinelibrary.wiley.com/doi/10.1890/15-0342.1/fullPearse, I.S., Altermatt, F. 2015. Out of sample predictions from plant-insect food webs: robustness to missing and erroneous trophic interaction records. Ecological Applications. http://onlinelibrary.wiley.com/doi/10.1890/14-1463.1/fullPearse, I.S., Baty, J.H., Herrmann, D.L., Sage, R., Koenig, W.D. 2015. Leaf phenology mediates provenance differences in herbivore populations on valley oaks in a common garden. Ecological Entomology. http://onlinelibrary.wiley.com/doi/10.1111/een.12219/full
Hughes, K.A., Pearse, I.S., Gof-Tizsa, P., Karban, R. 2015. Individual-level differences in generalist caterpillar responses to a plant-plant signal. Ecological Entomology. http://onlinelibrary.wiley.com/doi/10.1111/een.12224/fullPearse, I.S., Funk, K.A., Kraft, T.S., Koenig, W.D. 2015. Lagged effects of early‑season herbivores on valley oak fecundity. Oecologia 178: 361-368. http://link.springer.com/article/10.1007/s00442-014-3193-2
Petchey, O.L., Pontarp, M., Massie, T.N., Kéfi, S., Ozgul, A., Weilenmann, M., Palamara, G.C., Altermatt, F., Matthews, B.J., Levine, J.M., Childs, D.Z., McGill, B.J., Schaepman, M.E., Schmid, B., Spaak, P., Beckerman, A.P., Pennekamp, F., Pearse, I.S. 2015. The Ecological Forecast Horizon, and examples of its uses and determinants. Ecology Letters. http://onlinelibrary.wiley.com/doi/10.1111/ele.12443/fullPearse, I.S., Hipp, A.L. 2014. Native plant diversity increases herbivory to non-natives. Proceedings of the Royal Society – B 281: 20141841. http://rspb.royalsocietypublishing.org/content/281/1794/20141841.shortDesurmont, G., Pearse, I.S. Alien plants versus alien herbivores: does it matter who is non-native in a novel trophic interaction? Current Opinion in Insect Science 2: 20-25. http://www.sciencedirect.com/science/article/pii/S221457451400035Krimmel, B.A., Pearse, I.S. 2014. Generalist and sticky plant specialist predators suppress herbivores on a sticky plant. Arthropod Plant Interactions 8: 403-410. http://link.springer.com/article/10.1007/s11829-014-9318-zPearse, I.S., Cobb, R.C., Karban, R. 2014. The phenology substrate match hypothesis explains decomposition rates of evergreen and deciduous oak leaves. Journal of Ecology 102: 28-35. http://onlinelibrary.wiley.com/doi/10.1111/1365-2745.12182/fullKoenig, W.D., Walters, E.L., Pearse, I.S., Knops, J.M.H. 2014. Serotiny in California oaks. Madroño 61(2): 151-158. http://www.bioone.org/doi/full/10.3120/0024-9637-61.2.151
Pearse, IS, Koenig, WD, Knops, JMH. 2014. Cues versus proximate drivers: testing the mechanism behind masting behavior. Oikos 123: 179-184 http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0706.2013.00608.x/fullKarban, R., Huntzinger, M., Pearse, I.S. 2014. How to Do Ecology: A Concise Handbook, 2nd edition. Princeton University Press, Princeton. http://press.princeton.edu/titles/10284.htmlPearse, I.S., Bastow, J.L., Tsang, A. 2014. Radish introduction affects soil biota but has a positive impact on the growth of a native plant. Oecologia 174: 471-478. http://link.springer.com/article/10.1007/s00442-013-2779-4Pearse, I.S., Griswold, S., Pizarro, D., Koenig, W.D. 2014. Stage and size structure of three species of oaks in central coastal California. Madroño 61(1): 1-8. http://www.bioone.org/doi/abs/10.3120/0024-9637-61.1.1
Pearse, I.S., Gee, W.S., Beck, J.J. 2013. Headspace volatiles from 52 oak species advertise induction, species identity, and evolution, but not defense. Journal of Chemical Ecology 39: 90-100. http://link.springer.com/article/10.1007/s10886-012-0224-5Pearse, I.S. and Altermatt, F. 2013. Extinction cascades partially estimate observed herbivore losses in a Lepidoptera-plant food web. Ecology 94(8): 1785-1794 (Cover article). http://onlinelibrary.wiley.com/doi/10.1890/12-1075.1/fullPearse, I.S., Hughes, K., Shiojiri, K., Ishizaki, S., Karban, R. 2013. Interplant volatile signaling in willows: revisiting the original talking trees. Oecologia 172: 869-875 (Cover article). http://link.springer.com/article/10.1007/s00442-013-2610-2Pearse, I.S. and Karban, R. 2013. Leaf drop affects herbivory in oaks. Oecologia 173: 925-932. http://link.springer.com/article/10.1007/s00442-013-2689-5
Pearse, I.S., Harris, D.J., Karban, R., Sih, A. 2013.Predicting novel herbivore-plant interactions. Oikos 122: 1554-1564. http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0706.2013.00527.x/fullPearse, I.S. and Altermatt F. 2013. Predicting novel trophic interactions in a non-native world. Ecology Letters 16: 1088-1094. http://onlinelibrary.wiley.com/doi/10.1111/ele.12143/fullKrimmel, B.A. and Pearse, I.S. 2013. Sticky plants trap invertebrate carrion to enhance indirect defense. Ecology Letters. 16: 219-224 (featured in Nature). http://onlinelibrary.wiley.com/doi/10.1111/ele.12032/fullSavchenko, T., Pearse, I.S., Karban, R., DeHesh, K. 2013. Insect feeding habits determine the composition of hydroperoxide lyase-derived metabolites. The Plant Journal 73: 653-662. http://onlinelibrary.wiley.com/doi/10.1111/tpj.12064/full
Pearse, I.S., Karban, R. 2013. Do plant-plant signals mediate herbivory consistently in multiple taxa and ecological contexts? Journal of Plant Interactions 8(3): 203-206. http://www.tandfonline.com/doi/abs/10.1080/17429145.2013.765511Pearse, I.S. and Hipp, A.L. 2012. Global patterns of leaf defenses in oak species. Evolution. 66(7): 2272-2286. http://onlinelibrary.wiley.com/doi/10.1111/j.1558-5646.2012.01591.x/full
Herrmann, D.L., Pearse, I.S., Baty, J.H. 2012. Drivers of specialist herbivore diversity across 10 cities. Landscape and Urban Planning 108: 123-130. http://www.sciencedirect.com/science/article/pii/S0169204612002617Pearse, I.S., Parensky, L.M., Yang, L.H., Stanton, M.L., Karban, R., Bhattacharyya, L., Dove, K., Higgins, A., Kamaroff, C., Kirk, T., Knight, C., Koch, R., Rollins, H., Tanner, K., Cox, R. 2012. Complex consequences of herbivory and interplant cues in three annual plants. PlosOne 7(5): e38105. http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0038105Pearse, I.S. and Baty, J.H. 2012. The predictability of traits and ecological interactions on 17 different crosses of hybrid oaks. Oecologia 169: 489-497. http://link.springer.com/article/10.1007/s00442-011-2216-5
Pearse, I.S. 2012. The role of leaf defensive traits in oaks on the preference and performance of a polyphagous herbivore, Orgyia vetusta. Ecological Entomology 36(5): 635-642. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2311.2011.01308.x/fullAltermatt, F., Pearse, I.S. 2011. Similarity and specialization of the larval versus adult diets of European butterflies and moths. The American Naturalist 178(3): 372-378. http://www.jstor.org/stable/10.1086/661248?seq=1#page_scan_tab_contentsJoseph, M., Gentles, M., Pearse, I.S. 2011. The parasitoid community of Andricus quercuscalifornicus (Hymenoptera: Cynipidae) is associated with gall size and host phenology. Biodiversity and Conservation 20: 203-216.
http://link.springer.com/article/10.1007/s10531-010-9956-0Pearse I.S. 2011. Novel herbivore-plant interactions: Evidence from non-native oaks (Dissertation) U. California – Davis. http://gradworks.umi.com/34/99/3499479.html
Pearse, I.S. 2010. Bird rookeries have different effects on different feeding guilds of herbivores and alter the feeding behavior of a common caterpillar. Arthropod Plant Interactions 4: 189-195. http://link.springer.com/article/10.1007/s11829-010-9098-zKarban, R., C. Karban, Huntzinger, M., Pearse, I., Crutsinger, G. 2010. Diet mixing enhances the performance of a generalist caterpillar, Platyprepia virginalis. Ecological Entomology 35(1): 92-99. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2311.2009.01162.x/fullPearse, I.S. and A.L. Hipp. 2009. Phylogenetic and trait similarity to a native species predict herbivory on non-native oaks. Proceedings of the National Academy of Sciences of the United States of America 106(43): 18097-18102. (Cover article)
http://www.pnas.org/content/106/43/18097.short
Pearse, I, Zhu, Y, Murray, E, Dudeja, P, Ramaswamy, K, Malakooti, J. 2007. Sp1 and Sp3 control constitutive expression of the human NHE2 promoter by interactions with the proximal promoter and the transcription initiation site. Biochemical Journal 407: 101-111. http://www.biochemj.org/content/407/1/101.abstract
Pearse, IS, Krügel, T, Baldwin, IS. 2006. Innovation in anti-herbivore defense systems during neopolyploidy - the functional consequences of instantaneous speciation. The Plant Journal 47: 196-210. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-313X.2006.02776.x/fullPearse, I.S., Heath, K.D., Cheeseman, J.M. 2006. Biochemical and ecological characterization of two peroxidase isoenzymes from the mangrove, Rhizophora mangle. Plant, Cell and Environment 28: 612-622 (Cover article).
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-3040.2005.01307.x/full - News