Walt Koenig's Research
My research spans the fields of behavioral ecology and cooperative breeding, population ecology of birds, spatial synchrony of ecological phenomena, and the evolutionary ecology of variable reproduction (masting behavior) in trees.
A complete list of publications along with more pdfs of papers is available here. I have copies of most of the others; feel free to email me if you need one.
Behavioral ecology of cooperative breeding
Evolutionary ecology of variable reproduction in plants
Spatial synchrony of ecological phenomena
For a relatively current update on cooperative breeding studies:
Cooperative Breeding in Vertebrates: Studies of Ecology, Evolution, and Behavior, W. D. Koenig and J. L. Dickinson, editors (Cambridge University Press), 2016.
Behavioral ecology of cooperative breeding
Since 1974 I have been involved in a long-term study of the ecology and evolution of social behavior in the cooperatively breeding acorn woodpecker (Melanerpes formicivorus) at Hastings Reservation in central coastal California, currently in collaboration with Dr. Eric Walters (Old Dominion University) and Dr. Joseph Haydock (Gonzaga University). The mating system of this species is one of the most complex of any vertebrate, with social units consisting of up to seven related males competing for matings with up to three related females, all laying eggs in a single nest, and up to 10 nonbreeding helpers of both sexes (offspring from prior years). Our current work focuses on understanding the formation of coalitions and implementing an automatic tracking system using solar-powered 'nanotags' whose signal is picked up by a series of base stations located throughout the study area. My work on cooperative breeding in acorn woodpeckers has been supported by a series of grants from the NSF going back over 30 years. Selected publications since 2011 related to this project include:
Koenig, W. D., E. L. Walters, and J. Haydock. 2011. Variable helper effects, ecological conditions, and the evolution of cooperative breeding in the acorn woodpecker. American Naturalist 178: 145-158. pdf
Koenig, W. D. and E. L. Walters. 2011. Age-related provisioning behaviour in the cooperatively breeding acorn woodpecker: testing the skills and the pay-to-stay hypotheses. Animal Behaviour 82: 423-424. pdf
Koenig, W. D. and E. L. Walters. 2012. Brooding, provisioning, and compensatory care in the cooperatively breeding acorn woodpecker. Behavioral Ecology 23: 181-190. pdf
Rusk, C. L, E. L. Walters, and W. D. Koenig. 2013. Cooperative breeding and long-distance dispersal: a test using vagrant records. PLoS One 8(3): e58624. pdf
Koenig, W. D. and E. L. Walters. 2014. What we don't know, and what needs to be known, about the cooperatively breeding acorn woodpecker Melanerpes formicivorus. Acta Ornithologica 49: 221-232. pdf
McMahon, D. E., I. S. Pearse, W. D. Koenig, and E. L. Walters. 2015. Tree community shifts and acorn woodpecker population increases over three decades in a Californian oak woodland. Canadian Journal of Forest Research 45: 1113-1120. pdf
Koenig, W. D. and E. L. Walters. 2015. Temporal variability and cooperative breeding: testing the bet-hedging hypothesis in the acorn woodpecker. Proceedings of the Royal Society B 282: 20151742. pdf
Koenig, W. D., E. L. Walters and J. Haydock. 2016. Acorn woodpeckers: helping at the nest, polygynandry, and dependence on a variable acorn crop. Pp. 217-236 in Cooperative Breeding in Vertebrates: Studies in Ecology, Evolution, and Behavior. (W. D. Koenig and J. L. Dickinson, eds.). Cambridge University Press, Cambridge. pdf
Koenig, W. D., J. L. Dickinson and S. T. Emlen. 2016. Synthesis: cooperative breeding in the 21st century. Pp. 353-374 in Cooperative Breeding in Vertebrates: Studies in Ecology, Evolution, and Behavior. (W. D. Koenig and J. L. Dickinson, eds.). Cambridge University Press, Cambridge. pdf
Koenig, W. D. and E. L. Walters. 2016. Provisioning patterns in the cooperatively-breeding acorn woodpecker: is feeding a signal, and if so, to whom and why? Animal Behaviour 119: 125-134. pdf
Shen, S.-F., S. T. Emlen, W. D. Koenig, and D. R. Rubenstein. 2017. The ecology of cooperative breeding behavior. Ecology Letters 20: 708-720.
Koenig, W. D.. 2017. What drives cooperative breeding? PLoS Biology 15(6): e2002965. pdf
Koenig, W. D. and E. L. Walters. 2018. Causes of seasonal decline in reproduction of the cooperatively-breeding acorn woodpecker. Journal of Avian Biology 49: e01784 pdf
Pardo, M.A., E. A. Sparks, T. S. Kuray, N. D. Hagemeyer, E. L. Walters, and W. D. Koenig. 2018. Wild acorn woodpeckers recognize associations between individuals in other groups. Proceedings of the Royal Society B 285: 20181017. pdf
Barve, S., W. D. Koenig, J. Haydock, and E. L. Walters. 2019. Habitat saturation results in joint-nesting female coalitions in a social bird. American Naturalist 193: 830-840. pdf
Koenig, W. D., E. L. Walters, and S. Barve. 2019. Does helping-at-the-nest help? The case of the acorn woodpecker Frontiers in Ecology and Evolution 7:272. doi: 10.3389/fevo.2019.00272. pdf
Koenig, W. D., E. L. Walters, P.B. Stacey, M T. Stanback, and R. L. Mumme. 2019. Acorn woodpecker (Melanerpes formicivorus). In: Birds of North America (P. G. Rodewald, editor) Cornell Lab of Ornithology, Ithaca, NY https://doi-org.proxy.library.cornell.edu/10.2173/bna.acowoo.02.
Barve, S., N. D. G.Hagemeyer, R. E. Winter, S. D. Chamberlain, W. D. Koenig, D. W. Winkler, and E. L. Walters. 2020. Wandering woodpeckers: foray behavior in a social bird. Ecology 101: e02943. pdf
Barve, S., A. S. Lahey, R. M. Brunner, W. D. Koenig, and E. L. Walters. 2020. Wodpecker wars: tracking warriers and spectators with telemetry. Current Biology 30: R982-R983. pdf
Pardo, M. A., C. E. Hayes, E. L. Walters, and W. D. Koenig. 2020. Acorn woodpeckers vocally discriminate current and former group members from non-group members. Behavioral Ecology 31: 1120-1128. pdf
Pardo, M. A., E. L. Walters, and W. D. Koenig. 2020. Experimental evidence that acorn woodpeckers recognize relationships among third parties no longer living. Behavioral Ecology 31: 1257-1265. pdf
Koenig, W. D., E. M. Hallock, D. J. Weber, and E. L. Walters. 2021. Nest cavity reuse by the cooperatively breeding acorn woodpecker. Ornithology138: ukaa088. pdf
Koenig, W. D., A. C. B. Prinz, J. Haydock, H. L. Dugdale, and E. L. Walters. 2021. Are you my baby? Testing whether paternity affects behavior of cobreeder male acorn woodpeckers. Behavioral Ecology 32: 865-874. pdf
Barve, S., C.Riehl, E. L. Walters, J. Haydock, H. L. Dugdale, and W. D. Koenig. 2021. Lifetime reproductive benefits of cooperative polygamy vary for males and females in the acorn woodpecker (Melanerpes formicivorus). Proceedings of the Royal Society B 288: 20210579. pdf
Koenig, W. D., S. Barve, J. Haydock, H. L. Dugdale, M. K. Oil, and E. L. Walters 2023. Lifetime inclusive fitness effects of cooperative polygamy in the acorn woodpecker. Proceedings of the National Academy of Science (USA) 120: e2219345120. pdf
Hagemeyer, N.D.G., M. B. Pesendorfer, W. D. Koenig, and E. L. Walters. 2023. Investigating the drivers of temporal occupancy-abundance relationships in a cooperatively breeding bird. Landscape Ecology 38: 1955-1970. pdf
Koenig, W. D., J. Haydock, H. L. Dugdale, and E. L. Walters. 2023. Territory inheritance and the evolution of cooperative breeding in the acorn woodpecker. Animal Behaviour 205: 241-249. pdf
Information on the bizarre social behavior of the acorn woodpecker is available on the Hastings Reservation web site here.
******* This study was funded for many years by the ******* ************* National Science Foundation ***************
Evolutionary ecology of variable reproduction in plants
This project includes several main parts. The first, in collaboration with Dr. Jean Knops of Xi'an Jiaotong Liverpool University, Bill Carmen of Mill Valley, and former postdoctoral scholars Ian Pearse and Mario Pesendorfer, focuses on the behavioral ecology of variable seed production by California oaks and involves a long-term study of the reproduction and growth of over 1,000 trees throughout California currently funded by an LTREB grant from NSF. This part of the project has its own website (The California Acorn Survey) and its own annual newsletter, the California Acorn Report, the most recent edition of which can be found at the California Acorn Survey website.
Second is a project on gene flow and the genetic ecology of valley oaks (Quercus lobata) in collaboration with Dr. Mary Ashley at the University of Illinois, Chicago. Third is a more general interest in the evolution of masting behavior and growth of forest trees. Selected recent papers related to these projects include the following; for a more complete list click here.
Koenig, W. D. and M. V. Ashley. 2003. Is pollen limited? The answer is blowin’ in the wind. Trends in Ecology & Evolution 18: 157-159.pdf
Koenig, W. D., D. Kelly, V. L. Sork, R. P. Duncan, J. S. Elkinton, M. S. Peltonen and R. D. Westfall. 2003. Dissecting components of population-level variation in seed production and the evolution of masting behavior. Oikos 102: 581-591. pdf
Koenig, W. D. and J. M. H. Knops. 2005. The mystery of masting in trees. American Scientist 93: 340-347. pdf
Knops, J. M. H., W. D. Koenig, and W. J. Carmen. 2007. A negative correlation does not imply a trade-off between growth and reproduction in California oaks. Proceedings of the National Academy of Sciences (USA) 104: 16982-16985. pdf
Koenig, W. D., K. A. Funk, T. S. Kraft, W. J. Carmen, B. C. Barringer, and J. M. H. Knops. 2012. Stabilizing selection for within-season flowering phenology confirms pollen limitation in a wind-pollinated tree. Journal of Ecology 100: 758-763. pdf
Barringer, B. C., W. D. Koenig, and J. M. H. Knops. 2012. Interrelationships among life-history traits in three California oaks. Oecologia 171: 129-139. pdf
Koenig, W. D. and J. M. H. Knops. 2013. Large scale spatial synchrony and cross-synchrony in acorn production by two California oaks. Ecology 94: 83-93. pdf
Pearse, I. S., W. D. Koenig and J. M. H. Knops. 2014. Cues versus proximate drivers: testing the mechanism behind masting behavior. Oikos 123: 179-184. pdf
Pearse, I. S., W. D. Koenig and K. A. Funk, and M. B. Pesendorfer. 2015. Pollen limitation and flower abortion in a wind-pollinated, masting tree. Ecology 96: 587-593. pdf
Koenig, W. D., J. M. H. Knops, W. J. Carmen and I. S. Pearse. 2015. What drives masting? The phenological synchrony hypothesis. Ecology 96: 184-192. pdf
Pesendorfer, M. B., W. D. Koenig ,I. S. Pearse, J. M. H. Knops, and K. A. Funk. 2016. Individual resource-limitation combined with population-wide pollen availability drives masting in the valley oak (Quercus lobata). Journal of Ecology 104: 637-645. pdf
Koenig, W. D., R. Alejano, M. D. Carbonero, P. Fernández-Rebollo, J. M. H. Knops, T. Marañón, C. M. Padilla-Díaz, I. S. Pearse, I. M. Pérez-Ramos, J. Vázquez-Piqué, and M. B. Pesendorfer. 2016. Is the relationship between mast-seeding and weather in oaks related to their life-history or phylogeny? Ecology 97: 2603-2615. pdf
Pearse, I. S. W. D. Koenig, and D. Kelly. 2016. [Tansley review] Mechanisms of mast seeding: resources, weather, cues, and selection. New Phytologist 212: 546-562. pdf
Koenig, W. D., J. M. H. Knops, W. J. Carmen, and M. B. Pesendorfer. 2017. Testing the terminal investment hypothesis in Caifornia oaks. American Naturalist 189: 564-569. pdf
Koenig, W. D., J. M. H. Knops, M. B. Pesendorfer, D. N. Zaya, and M. V. Ashley. 2017. Drivers of synchrony of acorn production in the valley oak (Quercus lobata) at two spatial scales. Ecology 98: 3056-3062. pdf
Pearse, I. S., J. M. LaMontagne, and W. D. Koenig. 2017. Interannual variation in seed production has increased over time. Proceedings of the Royal Society B 284: 20171666. doi: 10.1098/rspb.2017.1666. pdf
Koenig, W. D., J. M. H. Knops, W. J. Carmen, M. B. Pesendorfer, and J. L. Dickinson. 2018. Effects of mistletoe (Phoradendron villosum) on California oaks. Biology Letters 14: 20180240. pdf
Bogdziewicz, M., D. Ascoli, A. Hacket-Pain, W. D. Koenig, M. B. Pesendorfer, I. S. Pearse, A. Satake, P. Thomas, G. Vacciano, T. Wohlgemuth, and A. Tanentzap. 2020. From theory to experiments for testing the proximate mechanisms of mast seeding: an agenda for an experimental ecology. Ecology Letters 23: 210-220. pdf
LaMontagne, J., I. S. Pearse, D. F. Greene, and W. D. Koenig. 2020. Mast seeding patterns are asynchronous at a continental scale. Nature Plants 6:460-465. pdf
Pearse, I. S., LaMontagne, J. M., M. Lordon, A. L. Hipp, and W. D. Koenig. 2020. Biogeography and phylogeny of masting: do global patterns fit functional hypotheses? New Phytologist 227: 1557-1567. pdf
Koenig, W. D., J. M. H. Knops, and W. J. Carmen. 2020. Can mast history be inferred from raidal growth? A test using five species of California oaks. Forest Ecology and Management 472: 118233. pdf
Koenig, W. D., J. M. H. Knops, and W. J. Carmen. 2020. Intraspecific variation in the relationship between weather and masting behavior in valley oak Quercus lobata. Canadian Journal of Forest Research 50: 1299-1306. pdf
Koenig, W. D. 2021. A brief history of masting research. Philosophical Transfactions of the Royal Society B 376: 20200423. pdf
Koenig, W. D., M. B. Pesendorfer, I. S. Pearse, and J. M. H. Knops. 2021. Budburst timing of valley oaks at Hastings Reservation, central coastal California. Madroño 68: 434-442. pdf
Koenig, W. D., A. M. Liebhold, J. M. LaMontagne, and I. S. Pearse. 2022. Periodical cicada emergences affect masting behavior of oaks. American Naturalist 201: 755-762. pdf
*** This study was generously funded for many years by the *** ************* National Science Foundation **************
Avian population ecology
I have done considerable work investigating various aspects of avian ecology, often using large-scale public datasets such as the Audubon Christmas Bird Counts (CBC), the North American Breeding Bird Surveys (BBS), and the Lab of Ornithology's Project FeederWatch. The focus of this work has varied depending on the questions involved, but has generally involved identifying and explaining large-scale spatial patterns in population numbers and trends. Papers in this area include:
Koenig, W. D. 2003. European starlings and their effect on native cavity-nesting birds. Conservation Biology 17: 1134-1140. pdf
Koenig, W. D. and A. M. Liebhold. 2005. Effects of periodical cicada emergences on abundance and synchrony of avian populations. Ecology 86: 1873-1882. pdf
Monahan, W. B. and W. D. Koenig. 2006. Estimating the effects of sudden oak death on oak-dependent birds. Biological Conservation 127: 146-157. pdf
Koenig, W. D., L. Marcus, T. W. Scott, and J. L. Dickinson. 2007. West Nile virus and California breeding bird declines. EcoHealth 4: 18-24. pdf
Koenig, W. D., W. M. Hochachka, B. Zuckerberg, and J. L. Dickinson. 2010. Ecological determinants of American crow mortality due to West Nile virus during its North American sweep. Oecologia 163: 903-909. pdf
Koenig, W. D., L. Ries, V. B. K. Olsen, and A. M. Liebhold. 2011. Avian predators are less abundant during periodical cicada emergences, but why? Ecology 92: 784-790. pdf
Zuckerberg, B., D. N. Bonter, W. M. Hochachka, W. D. Koenig, A. T. DeGaetano, and J. L. Dickinson. 2011. Climatic constraints on wintering bird distributions are modified by urbanization and weather. Journal of Animal Ecology 80: 403-413 . pdf
Koenig, W. D., E. L. Walters, and A. M. Liebhold. 2011. Effects of gypsy moth outbreaks on North American woodpeckers. Condor 113: 352-361. pdf
Koenig, W. D. and A. M. Liebhold. 2013. Avian predation pressure as a potential driver of periodical cicada cycle length. American Naturalist 181: 145-149. pdf
Koenig, W. D., A. M. Liebhold, D. N. Bonter, W. M. Hochachka, and J. L. Dickinson. 2013. Effects of the emerald ash borer invasion on four species of birds. Biological Invasions 15: 2095-2103. pdf
Strong, C. B. Zuckerberg, J.L. Betancourt, and W. D. Koenig. 2015. Climate dipoles drive two principal modes of North American boreal bird irruption. Proceedings of the National Academy of Sciences (USA) 112: E2795-2802. pdf
Koenig, W. D. and A. M. Liebhold. 2016. Temporally increasing spatial synchrony of North American temperature and bird populations. Nature Climate Change 6: 614-617. pdf
Koenig, W. D., E. L. Walters, and P. G. Rodewald, 2017. Testing alternative hypotheses for the cause of population declines: the case of the Red-headed Woodpecker. Condor 119: 143-154. pdf
Koenig, W. D. and A. M. Liebhold. 2017. A decade of emerald ash borer effects on regional woodpecker and nuthatch populations. Biological Invasions 19: 2029-2037. pdf
Koenig, W. D. 2020.What are the competitive effects of invasive species? Forty years of the Eurasian Collared-dove in North America. Biological Invasions 22: 3645-3652. pdf
Koenig, W. D. and J. M. H. Knops. 2022. Drivers of winter population cycles in the varied thrush Ixoreus naevius Canadian Journal of Zoology 100: 607-613. pdf
Spatial synchrony of ecological phenomena
I am particularly interested in the patterns, causes, and consequences of spatial synchrony in ecological phenomena. This work, which overlaps with my interests in the reproductive strategies of forest trees and the ecological work on avian populations, has led me to investigate spatial synchrony in growth and reproduction by forest trees, global weather patterns, North American bird populations, and metapopulations of amphibians. Recent papers include:
Koenig, W. D. and A. M. Liebhold. 2003. Regional impacts of periodical cicadas on oak radial increment. Canadian Journal of Forest Research 33:1084-1089. pdf
Trenham, P. C., W. D. Koenig, M. J. Mossman, S. L. Stark, and L. A. Jagger. 2003. Regional dynamics of wetland-breeding frogs and toads: turnover and synchrony. Ecological Applications 13: 1522-1532. pdf
Liebhold, A. M., W. D. Koenig and O. Bjørnstad. 2004. Spatial synchrony in population dynamics. Annual Review of Ecology, Evolution, and Systematics 35: 467-490. pdf
Koenig, W. D. and J. M. H. Knops. 2013. Large scale spatial synchrony and cross-synchrony in acorn production by two California oaks. Ecology 94: 83-93. pdf
Koenig, W. D. and A. M. Liebhold. 2016. Temporally increasing spatial synchrony of North American temperature and bird populations. Nature Climate Change 6: 614-617. pdf
Barringer, B. C., W. D. Koenig, I. S. Pearse, and J. M. H Knops. 2020. Population ecology and spatial synchrony in the abundance of leaf gall wasps within and among populations of valley oak (Quercus lobata). Population Ecology 62: 220-232. pdf
Zuckerberg, B., C. Strong, J. M. LaMontagne, S. St. George, J. L. Betancourt, and W. D. Koenig. 2020. Climate dipoles as continental drivers of plant and animal populations. Trends in Ecology & Evolution 35: 440-453.pdf
You want more?? Are you sure?? For a exhaustive list of Walt's publications, click here (web page)or here (pdf).
