ArticleProceedings of the National Academy of Sciences of the United States of America2019
Multiscale seasonal factors drive the size of winter monarch colonies.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 23 papers.
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Who cites it
23 citing papers in PubMed.
- Article
- Eastern North American Monarch Butterfly Conservation Needs and Opportunities: What the Science Tells Us.Insects · 2026Review
- The impact of temperature on the reproductive development, body condition and mortality of autumn migrating monarch butterflies in the laboratory.Royal Society open science · 2025Article
- Artificial intelligence correctly classifies developmental stages of monarch caterpillars enabling better conservation through the use of community science photographs.Scientific reports · 2024Article
- Dramatic recent declines in the size of monarch butterfly (Proceedings of the National Academy of Sciences of the United States of America · 2024Article
- Changes in landscape and climate in Mexico and Texas reveal small effects on migratory habitat of monarch butterflies (Danaus plexippus).Scientific reports · 2024Article
- Decoupling of bird migration from the changing phenology of spring green-up.Proceedings of the National Academy of Sciences of the United States of America · 2024Article
- Weekly Forecasting of Yellow Fever Occurrence and Incidence via Eco-Meteorological Dynamics.GeoHealth · 2023Article
- Migratory behaviour is positively associated with genetic diversity in butterflies.Molecular ecology · 2023Article
- Dynamics of stored lipids in fall migratory monarch butterflies (Conservation physiology · 2023Article
- Opposing global change drivers counterbalance trends in breeding North American monarch butterflies.Global change biology · 2022Article
- Article
- Changes in climate drive recent monarch butterfly dynamics.Nature ecology & evolution · 2021Article
- Mapping the premigration distribution of eastern Monarch butterflies using community science data.Ecology and evolution · 2021Article
- Environmental drivers of annual population fluctuations in a trans-Saharan insect migrant.Proceedings of the National Academy of Sciences of the United States of America · 2021Article
- The 'migratory connectivity' concept, and its applicability to insect migrants.Movement ecology · 2020Review
- Genomic evidence for gene flow between monarchs with divergent migratory phenotypes and flight performance.Molecular ecology · 2020Article
- Linking landscape-scale conservation to regional and continental outcomes for a migratory species.Scientific reports · 2020Article
- The Dynamic Shift Detector: An algorithm to identify changes in parameter values governing populations.PLoS computational biology · 2020Article
- Reply to Wepprich and Ries et al.: Alternative methods do not provide support for the contribution of GM crops to monarch declines.Proceedings of the National Academy of Sciences of the United States of America · 2019Article
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7 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Monarch butterflies in eastern North America have declined by 84% on Mexican wintering grounds since the observed peak in 1996. However, coarse-scale population indices from northern US breeding grounds do not show a consistent downward trend. This discrepancy has led to speculation that autumn migration may be a critical limiting period. We address this hypothesis by examining the role of multiscale processes impacting monarchs during autumn, assessed using arrival abundances at all known winter colony sites over a 12-y period (2004-2015). We quantified effects of continental-scale (climate, landscape greenness, and disease) and local-scale (colony habitat quality) drivers of spatiotemporal trends in winter colony sizes. We also included effects of peak summer and migratory population indices. Our results demonstrate that higher summer abundance on northern breeding grounds led to larger winter colonies as did greener autumns, a proxy for increased nectar availability in southern US floral corridors. Colony sizes were also positively correlated with the amount of local dense forest cover and whether they were located within the Monarch Butterfly Biosphere Reserve, but were not influenced by disease rates. Although we demonstrate a demographic link between summer and fine-scale winter population sizes, we also reveal that conditions experienced during, and at the culmination of, autumn migration impact annual dynamics. Monarchs face a growing threat if floral resources and winter habitat availability diminish under climate change. Our study tackles a long-standing gap in the monarch's annual cycle and highlights the importance of evaluating migratory conditions to understand mechanisms governing long-term population trends.
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