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MLMP Findings

We are constantly analyzing the numbers of monarchs found by MLMP volunteers every year, looking for changes and trends in population numbers. We’ve also shared a lot of MLMP data with the scientific community in several publications. Here are summaries of a few of these publications; you can link to the full publication of most papers.

  1. Oberhauser K.S., Elmquist D., Perilla-Lopez J.M., Gebhard I., Lukens L., and Stireman J. (2017) Tachinid Fly (Diptera: Tachinidae) Parasitoids of Danaus plexippus (Lepidoptera: Nymphalidae). Annals of the Entomological Society of America, 110(6), pp. 536–543, DOI: 10.1093/aesa/sax048
  2. Kasten K., Stenoien C., Caldwell W., Oberhauser K.S. Can roadside habitat lead monarchs on a route to recovery? Journal of Insect Conservation. 2016:1-1.
  3. Lewandowski, E.J. & Oberhauser, K.S. 2016a. Butterfly Citizen Science Projects Support Conservation Activities among their Volunteers. Citizen Science: Theory and Practice, 1(1): 6, pp. 1–8, DOI:
  4. Lewandowski, E.J. & Oberhauser, K.S. 2016b. Contributions of citizen scientists and habitat volunteers to monarch butterfly conservation. Human Dimensions of Wildlife. DOI: 10.1080/10871209.2017.1250293.
  5. McCoshum, S., Andreoli, S., Stenoien, C., Oberhauser, K., Baum, K. (2016) Species distribution models for natural enemies of monarch butterfly (Danaus plexippus) larvae and pupae: distribution patterns and implications for conservation. Journal of Insect Conservation. DOI: 10.1007/s10841-016-9856-z
  6. Semmens, B. X., D. J. Semmens, W. E. Thogmartin, R. Wiederholt, L. Lopez-Hoffman, J. E. Diffendorfer, J. M. Pleasants, K. S. Oberhauser, and Taylor O. R. (2016) Quasi-extinction risk and population targets for the Eastern, migratory population of monarch butterflies (Danaus plexippus). Scientific Reports 6: 23265.
  7. Stenoien, C., Nail, K. R., Zalucki, J. M., Parry, H., Oberhauser, K. S. and Zalucki, M. P. (2016) Monarchs in decline: A collateral landscape level effect of modern agriculture. Insect Science. Accepted Author Manuscript. doi:10.1111/1744-7917.12404
  8. Anda, A., Oberhauser, K.S. (2015) Invertebrate Natural Enemies and Stage-Specific Mortality Rates of Monarch Eggs and Larvae. Monarchs in a Changing World: Biology and Conservation of an Iconic Insect. 5: 60-70.
  9. Nail, K.R., Batalden, R.V., Oberhauser, K.S. (2015) What's Too Hot and What's Too Cold: Lethal and Sublethal Effects of Extreme Temperatures on Developing Monarchs. Monarchs in a Changing World: Biology and Conservation of an Iconic Butterfly. 8: 99-108.
  10. Nail, K.R., Stenoien, C., Oberhauser, K.S. (2015) Immature Monarch Survival: Effects of Site Characteristics, Density, and Time. Annals of the Entomological Society of America. 108 (5) 650-690; DOI:
  11. Oberhauser, K.S., Anderson, M., Anderson, S., Caldwell, W., Anda, A., Hunter, M., Kaiser, M.C., Solensky, M.J. (2015) Lacewings, Wasps, and Flies-Oh My: Insect Enemies Take a Bite out of Monarchs. Monarchs in a Changing World: Biology and Conservation of an Insect Icon. 6: 71-82.
  12. Oberhauser, K.S., Ries, L., Altizer, S., Batalden, R.V., Kudell-Ekstrum, J., Garland, M., Howard, E., Jepsen, S., Lovett, J., Monroe, M., Morris, G., Rendon-Salinas, E., RuBino, R.G., Ryan, A., Taylor, O.R., Trevino, R., Villablanca, F.X., Walton, D. Contributions to Monarch Biology and Conservation through Citizen Science. Monarchs in a Changing World: Biology and Conservation of an Iconic Butterfly. 2: 13-30.
  13. Stenoien, C., Nail, K.R., Oberhauser, K.S. (2015a) Habitat Productivity and Temporal Patterns of Monarch Butterfly Egg Densities in the Eastern United States. Annals of the Entomological Society of America, 108 (5) 670-679; DOI:
  14. Stenoien, C. M., S. McCoshum, W. Caldwell, A. D. Anda, and Oberhauser, K.S. (2015b) New reports that monarch butterflies (Lepdiotera: Nymphalidae, Danaus plexippus Linnaeus) serve as hosts for a pupal parasitoid (Hymenoptera: Chalcidoidae, Pteromalus cassotis Walker) in the Eastern United States. J. Kans. Entomol. Soc. 88: 16–26.
  15. Ries, L., Oberhauser, K.S. (2015) A citizen-army for science: Quantifying the contributions of citizen scientists to our understanding of monarch butterfly biology. Bioscience 65: 419–420; DOI: 10.1093/biosci/biv011
  16. Young Isebrand, E., Oberhauser, K.S., Bailey, K.,Charest, S., Hayes, B., Howard, E., Lovett, J., Meyers, S., Mollenhauer, E., Montesinos-Patino, E., Ryan, A., Taylor, O.R., Trevino, R. (2015) Environmental Education and Monarchs: Reaching across Disciplines, Generations, and Nations. Monarchs in Changing World: Biology and Conservation of an Iconic Butterfly. 1: 5-13.
  17. Oberhauser, KS. 2012. Tachinid flies and monarch butterflies: Citizen Scientists document parasitism patterns over broad spatial and temporal scales. American Entomologist 58:19-22.
  18. Pleasants, J, KS Oberhauser. 2012. Milkweed loss in agricultural fields because of herbicide use: Effect on the monarch butterfly population. Insect Conservation and Diversity. DOI:10.1111/j.1752-4598.2012.00196.x
  19. Lindsey E, Mehta M, Dhulipala V, Oberhauser K, Altizer S (2009) Crowding and disease: effects of host density on response to infection in a butterfly-parasite interaction. Ecological Entomology 34: 551–561. doi: 10.1111/j.1365-2311.2009.01107.x
  20. Kountoupes, D., and K. S. Oberhauser. 2008. Citizen science and youth audiences: Educational outcomes of the Monarch Larva Monitoring Project. Journal of Community Engagement and Scholarship. 1:10-20.
  21. Oberhauser, K. S. and M. D. Prysby. 2008. Citizen Science: Creating a Research Army for Conservation. American Entomologist 54:97-99.
  22. Batalden, R., K.S. Oberhauser, A.T. Peterson. 2007. Ecological niches in breeding generations of Eastern North American monarch butterflies. Environmental Entomology. 36:1365-1373.
  23. Oberhauser, K. S., I. Gebhard, C. Cameron, S. Oberhauser. 2007. Parasitism of monarch butterflies (Danaus plexippus) by Lespesia archippivora (Diptera: Tachinidae). Amer. Midl. Nat. 157:312-328.
  24. Prysby, M, KS Oberhauser. 2004. Temporal and geographical variation in monarch densities: Citizen scientists document monarch population patterns. Pp. 9-20 in: Oberhauser, KS, MJ Solensky (Eds.). The Monarch Butterfly: Biology and Conservation. Cornell University Press. Ithaca NY.
  25. Prysby, M. 2004. Natural Enemies and Survival of Monarch Eggs and Larvae. Pp. 27-38. In Oberhauser, K.S. & M.J. Solensky, eds. The Monarch Butterfly: Biology and Conservation. Cornell University Press. Ithaca NY.
  26. Oberhauser, K.S., Prysby, M.D., Mattila, H.R., Stanley-Horn, D.E., Sears, M.K., Dively, G., Olson, E., Pleasants, J.M., Lam. W.F. & Hellmich, R. 2001. Temporal and spatial overlap between monarch larvae and corn pollen. Proc. Nat. Acad. Sci. 98 (21): 11913-11918.
  27. Batalden, R.V., Oberhauser, K.S. (2015) Potential Changes in Eastern North American Monarch Migration in Response to an Introduced Milkweed, Asclepias curassavica. Monarchs in a Changing World: Biology and Conservation of an Iconic Butterfly. 19: 215-224.
  28. Pleasants, J.M. 2015. Monarch Butterflies and Agriculture. Monarchs in a Changing World: Biology and Conservation of an Iconic Butterfly. 14: 169-178.
  29. Prysby, M. and K. Oberhauser. 1999. Large scale monitoring of monarch populations. Proceedings of the 1997 North American conference on the Monarch Butterfly, pp. 379-384. Hoth, J, I. Pisanty, K. Oberhauser, L. Merino and S. Price, editors.
  30. Rea, B., K. Oberhauser, M. Quinn. 2002. A field guide to invertebrates on milkweed. (96 pp.) Bas Relief Publishing Group, Pennsylvania.
  31. Ries, L., Taron, D.J., Rendon-Salinas, E., Oberhauser, K.S. (2015) Connecting Eastern Monarch Population Dynamics across Their Migratory Cycle. Monarchs in a Changing World: Biology and Conservation of an Iconic Butterfly. 24: 268-281.