Peer-reviewed published literature which uses the Thanksgiving Count dataset
Crone, E. E., E. M. Pelton, L. M. Brown, C. C. Thomas, and C. B. Schultz. 2019. Why are monarch butterflies declining in the west? understanding the importance of multiple correlated drivers. Ecological Applications: A Publication Of The Ecological Society Of America 29:e01975. PDF
Pelton, E. M., C. B. Schultz, S. J. Jepsen, S. H. Black, and E. E. Crone. 2019. Western monarch population plummets: status, probable causes, and recommended conservation actions. Frontiers In Ecology And Evolution 7:258.
Schultz, C.B., L.M. Brown, E. Pelton, and E.E. Crone. 2017. Citizen science monitoring demonstrates dramatic declines of monarch butterflies in western North America Biological Conservation. 214:343-346.
Espeset, A.E., J.G. Harrison, A.M. Shapiro, C.C. Nice, J.H. Thorne, D.P. Waetjen, J.A. Fordyce, and M.L. Forister. 2016. Understanding a migratory species in a changing world: climatic effects and demographic declines in the western monarch revealed by four decades of instensive monitoring. Oecologia. 2016 Mar 21:1-2.
Jepsen, S. and S.H. Black. 2015. Understanding and conserving the western North American monarch population. In Oberhauser, K.S., K.R. Nail, and S.M. Alitizer, eds. Monarchs in a Changing World: Biology and Conservation of an Iconic Insect. Ithaca, USA: Cornell University Press.
Ries, L. and K. Oberhauser. 2015. A citizen army for science: quantifying the contributions of citizen scientists to our understanding of monarch butterfly biology. BioScience 65: 419-430.
Stevens, S.R. and D. Frey. 2010. Host plant pattern and variation in climate predict the location of natal grounds for migratory monarch butterflies in western North America. Journal of Insect Conservation 14: 731-744.
Vandenbosch, R. 2007. What do monarch population time series tell us about eastern and western population mixing? Journal of the Lepidopterists’ Society 61(1): 28-31.
Koenig, W. 2006. Spatial synchrony of monarch butterflies. The American Midland Naturalist 155(1): 39-49.
Frey, D. and A. Schaffner. 2004. Spatial and temporal patterns of monarch overwintering abundance in Western North America. In Oberhauser, K.S. and M.J. Solensky, eds. The Monarch Butterfly: Biology and Conservation. Ithaca: Cornell University Press.
Resources for Overwintering Site Management and Protection
The Xerces Society. Protecting California’s Butterfly Groves: Management Guidelines for Monarch Butterfly Overwintering Habitat. These guidelines provide an overview of the biology and conservation of western monarchs; step-by-step guidance for developing a site-specific management plan, and overall guidance on topics including tree management, shrub and forb management, and visitor and public access issues. The document also includes a list of monarch-attractive native nectar plants suitable for coastal areas. These guidelines will help site managers become familiar with overwintering monarch habitat needs and provides a roadmap to develop site-specific management plans to benefit monarchs in both the short- and long-term.
The Xerces Society. State of the Monarch Butterfly Overwintering Sites in California. This report builds upon data collected at over 400 overwintering sites in California including population trends and habitat conditions. A top 50 list prioritizes sites for protection and active management, with conservation profiles for the top 25 sites.
Bell, E., L.P. Brower, W.H. Calvert, J. Dayton, D. Frey, K. Leong, D. Murphy, R.M. Pyle, W. Sakai, K.B. Snow, and S. Weiss. 1993. The Monarch Project’s conservation and management guidelines for preserving the monarch butterfly migration and monarch overwintering habitat in California. A guide for land managers and community activists.