Modeling Migratory Patterns of the Eastern Monarch Butterfly

Modeling Migratory Patterns of the Eastern Monarch Butterfly

Karen Kesler (UNC Greensboro, USA) and Rick Bunch (UNC Greensboro, USA)
Copyright: © 2020 |Pages: 22
DOI: 10.4018/IJAGR.2020100103

Abstract

The purpose of this research was to relate the influence of specific site suitability variables to eastern monarch butterfly migratory patterns and behavior. Elevation, temperature, precipitation, and land use data layers were overlaid to collectively consider how these variables affected the way that butterflies migrated and recolonized during the 2016/2017 migratory cycle. The variables were reclassified into layers ranking suitability as either unsuitable, suitable, or optimal with respective scores of one, three, and five. Three uninhabitable variables were identified that deemed a site unsuitable despite the influence and possible optimal suitability of the other variables. The results of this study indicated that site suitability was a large driving factor for migratory monarchs with a heavier emphasis placed on average temperature and land/cropland use. Possible displaced and sink populations were identified for further study, while the effects of agriculture, development, and climate change were considered regarding flyway connectivity and behavior.
Article Preview
Top

Introduction

Migratory species are known to traverse a wide variety of physical conditions and landscapes over an infinite combination of spatial and temporal ranges. Given the fluctuations that can occur on these journeys, migratory species must be able to quickly adapt to their surroundings and remain sensitive to triggers that indicate that it is time to vacate a certain area. However, with recent fears of climate change that have already affected several endemic species, scientists are questioning what the future may hold for migratory species, and if the entire migratory phenomenon may be at risk (Thogmartin et al., 2017a). Eastern monarch butterflies (Danaus plexippus) have received attention due to the challenges that they face while completing their 3000-mile annual migration and recolonization. Destruction of overwinter sites, herbicide and pesticide use, agriculture practices, and changing climate have all been listed as threats to a species of insect that has migratory roots that date to 1800 B.C. (Baumle, 2017). With unstable and erratic population counts becoming more frequent, understanding the conditions experienced along the migratory flyways has become necessary to streamline conservation efforts and to target the locations that need intervention and remediation.

This study investigated the relationship between Eastern monarch butterfly migratory patterns as they relate both directly and indirectly to physical, land use, and environmental factors. While butterfly behavior is rooted in biology and animal behavior studies, migratory behavior has a distinct geographical element. Previous studies have previously modeled monarch butterfly migrations; however, most models have relied heavily on statistical analyses across multiple migratory flight years. These studies have examined specific circumstances such as the effects of climate change on migratory behaviors (Lemoine, 2015), as well as multivariate analyses that explored the effects of specific herbicides, temperature, precipitation, and survival statistics (Thogmartin et al., 2017a). Dingle et al. (2005) utilized GIS and cartographic modeling to investigate the perceived distribution shift of Western monarch butterflies utilizing local collection and tag/recovery data as well as elevation and temperature as driving factors. With the availability of historic temperature and precipitation readings, land use and crop data, and elevation measurements, this study developed a geographic model that could begin to delineate optimal site conditions as well as sites that may require mitigation. Focusing on fractured flyways will better serve the efforts to improve recolonization rates as well as improve population numbers that reach the summer breeding grounds and overwinter sites.

Complete Article List

Search this Journal:
Reset
Open Access Articles
Volume 12: 4 Issues (2021): Forthcoming, Available for Pre-Order
Volume 11: 4 Issues (2020)
Volume 10: 4 Issues (2019)
Volume 9: 4 Issues (2018)
Volume 8: 4 Issues (2017)
Volume 7: 4 Issues (2016)
Volume 6: 4 Issues (2015)
Volume 5: 4 Issues (2014)
Volume 4: 4 Issues (2013)
Volume 3: 4 Issues (2012)
Volume 2: 4 Issues (2011)
Volume 1: 4 Issues (2010)
View Complete Journal Contents Listing