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
Ian Pearse, Ph.D.
Ian Pearse is an ecologist in the invasive species branch of the Fort Collins Science Center.
Biography
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
Date published: December 22, 2020
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 gro
Attribution: Fort Collins Science Center
Date published: December 17, 2020
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 fro
Attribution: Fort Collins Science Center
Date published: September 11, 2017
Long-term Trends in Midwestern Milkweeds and their Relevance for Monarchs
This is the dataset used in the BioScience publication of the same name.
Attribution: Region 3: Great Lakes, Fort Collins Science Center
Year Published: 2021
Long‐term surveys support declines in early‐season forest plants used by bumblebees
Populations of bumble bees and other pollinators have declined over the past several decades due to numerous threats, including habitat loss and degradation. However, we can rarely investigate the role of resource loss due to a lack of detailed long‐term records of forage plants and habitats.We use 22‐year repeated surveys of more than 262 sites...
Mola, John Michael; Richardson, Leif L; Spyreas, Greg; Zaya, David N.; Pearse, IanAttribution: Fort Collins Science Center, Ecosystems
Year Published: 2021
Direct and indirect effects of a keystone engineer on a shrubland-prairie food web
Keystone engineers are critical drivers of biodiversity throughout ecosystems worldwide. Within the North American Great Plains, the black‐tailed prairie dog is an imperiled ecosystem engineer and keystone species with well‐documented impacts on the flora and fauna of rangeland systems. However, because this species affects ecosystem structure and...
Duchardt, Courtney; Porensky, Lauren M.; Pearse, IanAttribution: Fort Collins Science Center, Ecosystems
Year Published: 2021
Negative effects of an allelopathic invader on AM fungal plant species drive community‐level responses
The mechanisms causing invasive species impact are rarely empirically tested, limiting our ability to understand and predict subsequent changes in invaded plant communities. Invader disruption of native mutualistic interactions is a mechanism expected to have negative effects on native plant species. Specifically, disruption of native plant‐fungal...
Roche, Morgan; Pearse, Ian; Bialic-Murphy, Lalasia; Kivlin, Stephanie N; Sofaer, Helen; Kalisz, SusanAttribution: Fort Collins Science Center, Ecosystems
Year Published: 2020
Phylogenetic escape from pests reduces pesticides on some crop plants
Pesticides are a ubiquitous component of conventional crop production but come with considerable economic and ecological costs. We tested the hypothesis that variation in pesticide use among crop species is a function of crop economics and the phylogenetic relationship of a crop to native plants because unrelated crops accrue fewer herbivores and...
Pearse, Ian; Rosenheim, JayAttribution: Fort Collins Science Center, Ecosystems
Year Published: 2020
Associational effects of plant ontogeny on damage by a specialist insect herbivore
Intraspecific variation in plant traits is a major cause of variation in herbivore feeding and performance. Plant defensive traits change as a plant grows, such that ontogeny may account for a substantial portion of intraspecific trait variation. We tested how the ontogenic stage of an individual plant, of an individual in the context of its...
Cope, Olivia; Becker, Zoe; Ode, Paul J.; Ryan, Paul; Pearse, IanAttribution: Fort Collins Science Center, Ecosystems
Year Published: 2020
Generalizing indirect defense and resistance of plants
Indirect defence, the adaptive top‐down control of herbivores by plant traits that enhance predation, is a central component of plant–herbivore interactions. However, the scope of interactions that comprise indirect defence and associated ecological and evolutionary processes has not been clearly defined. We argue that the range of plant traits...
Pearse, Ian; LoPresti, Eric; Schaeffer, Robert N.; Wetzel, William C.; Mooney, Kailen A.; Ali, Jared G.; Ode, Paul J.; Eubanks, Micky D.; Bronstein, Judith L.; Weber, Marjorie G.Attribution: Fort Collins Science Center, Ecosystems
Year Published: 2020
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...
LaMontagne, J. M.; Pearse, Ian; Greene, David A.; Koenig, W. D.Attribution: Fort Collins Science Center, Ecosystems
Year Published: 2020
Biogeography and phylogeny of masting: Do global patterns fit functional hypotheses?
1) Interannual variability of seed crops (CVp) has profound consequences for plant populations and food webs, where high CVp is termed ‘masting’. Here we ask: is global variation in CVp better predicted by plant or habitat differences consistent with adaptive economies of scale, in which flower and seed benefits increase disproportionately during...
Pearse, Ian; LaMontagne, Jalene; Lordon, Michael; Hipp, Andrew; Koenig, Walter D.Attribution: Fort Collins Science Center, Ecosystems
Year Published: 2020
Life-history plasticity and water-use trade-offs associated with drought resistance in a clade of California jewelflowers
Water limitation is a primary driver of plant geographic distributions and individual plant fitness. Drought resistance is the ability to survive and reproduce despite limited water, and numerous studies have explored its physiological basis in plants. However, it is unclear how drought resistance and trade-offs associated with drought resistance...
Pearse, Ian S.; Aguilar, Jessica; Strauss, SharonAttribution: Fort Collins Science Center, Ecosystems
Year Published: 2020
A modeling workflow that balances automation and human intervention to inform invasive plant management decisions at multiple spatial scales
Predictions of habitat suitability for invasive plant species can guide risk assessments at regional and national scales and inform early detection and rapid-response strategies at local scales. We present a general approach to invasive species modeling and mapping that meets objectives at multiple scales. Our methodology is designed to balance...
Young, Nicholas E.; Jarnevich, Catherine S.; Sofaer, Helen; Pearse, Ian; Sullivan, Julia; Engelstad, Peder; Stohlgren, Thomas J.Attribution: Fort Collins Science Center, Ecosystems
Year Published: 2020
Population ecology and spatial synchrony in abundance within and among populations of valley oak (Quercus lobata) leaf gall wasps
What factors drive population variability through space and time? Here we assess patterns of abundance of seven species of gall wasps in three genera occurring on the leaves of valley oaks (Quercus lobata ) at 10 sites throughout this species' statewide range in California, from 2000 to 2006. Our primary goals were to understand the factors...
Barringer, Brian; Koenig, Walter D.; Pearse, Ian; Knops, JeanAttribution: Fort Collins Science Center, Ecosystems
Year Published: 2020
From theory to experiments for testing the proximate mechanisms of mast seeding: An agenda for an experimental ecology
Highly variable and synchronised production of seeds by plant populations is called masting and is implicated in many important ecological processes, but how it arises remains poorly understood. The lack of experimental studies prevents underlying mechanisms from being explicitly tested, and thereby precludes meaningful predictions on the...
Bogdziewicz, M.; Ascoli, Davide; Hacket-Pain, Andrew; Koenig, W. D.; Pearse, Ian; Pesendorfer, Mario B.; Satake, A.; Thomas, P.; Vacchiano, Giorgio; Wohlgemuth, T.; Tanentzap, A.Attribution: Fort Collins Science Center, Ecosystems
Pre-USGS Publications
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
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
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
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
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
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
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
Date published: August 11, 2021
Field Research for the Benefit of Bees
USGS scientists take on the task of surveying native bee populations to understand what may put native bees at risk, and how to help them.
Date published: February 5, 2021
Fort Collins Science Center Scientists Share Expertise at Society for Range Management Meeting
Scientists from the US Geological Survey Fort Collins Science Center will be presenting on topics ranging from sage-grouse to invasive plant species at the upcoming Society for Range Management Annual Meeting.