scholarly journals A Method to Project Future Impacts From Threats and Conservation on the Probability of Extinction for North American Migratory Monarch (Danaus plexippus) Populations

2019 ◽  
Vol 7 ◽  
Author(s):  
Kristen J. Voorhies ◽  
Jennifer Szymanski ◽  
Kelly R. Nail ◽  
Mason Fidino
Keyword(s):  
North American ◽  
Danaus Plexippus ◽  
Probability Of Extinction

Low prevalence of the parasite Ophryocystis elektroscirrha at the range edge of the eastern North American monarch (Danaus plexippus) butterfly population

2021 ◽  
Author(s):  
Felipe Dargent ◽  
Sydney M Gilmour ◽  
Emma A Brown ◽  
Rees Kassen ◽  
Heather M Kharouba
Keyword(s):  
North American ◽  
Population Distribution ◽  
Danaus Plexippus ◽  
Range Limits ◽  
North American Population ◽  
Ophryocystis Elektroscirrha ◽  
Range Edge ◽  
Relative Contribution ◽  
Northern Edge ◽  
Butterfly Population

Every year monarch butterflies (Danaus plexippus Linnaeus, 1758) from the eastern North American population migrate from Mexico to Southern Canada in the spring. This northward migration has been shown to reduce monarch infection with the host-specific parasite Ophryocystis elektroscirrha (OE) (McLaughlin and Myers, 1970); yet, the prevalence of OE at their range limits, and the mechanism(s) responsible, is unknown. We assessed OE infection levels of monarchs at the northern edge of the eastern population distribution around Ottawa, Canada, and found extremely low levels of infection (~1% with upper confidence intervals close to 3%). Low OE infection levels are likely due to low densities of monarchs in this region and/or migratory escape effects, where migrating individuals leave behind areas with high density of conspecifics and high potential for parasite accumulation and transmission. Future work should aim to disentangle the relative contribution of these two mechanisms for governing the decrease in parasitism at the range limits of migratory populations.

scholarly journals Captive-reared migratory monarch butterflies show natural orientation when released in the wild

2020 ◽  
Author(s):  
Alana A. E. Wilcox ◽  
Amy E. M. Newman ◽  
Nigel E. Raine ◽  
D. Ryan Norris
Keyword(s):  
North American ◽  
Danaus Plexippus ◽  
Release Site ◽  
Flight Simulator ◽  
Monarch Butterflies ◽  
The Public ◽  
In The Wild ◽  
Automated Telemetry ◽  
Proper Orientation ◽  
Captive Rearing

AbstractEastern North American migratory monarch butterflies (Danaus plexippus) have faced sharp declines over the last two decades. Although captive rearing has been used as an important tool for engaging the public and supplementing conservation efforts, a recent study that tested monarchs in a flight simulator suggested that captive-reared monarchs lose their capacity to orient southward during fall migration to their Mexican overwintering sites. We raised offspring of wild-caught monarchs on swamp milkweed (Asclepias incarnata) and, after eclosion, individuals were either tested in a flight simulator or radio-tracked in the wild using array of over 100 automated telemetry towers. While only 33% (7/39) of monarchs tested in the flight simulator showed strong southeast to southwest orientation, 97% (28/29) of the radio-tracked individuals were detected by automated towers south or southeast of the release site, up to 200 km away. Our results suggest that, though captive rearing of monarch butterflies may cause temporary disorientation, proper orientation is likely re-established after exposure to natural skylight cues.

scholarly journals Contemporary loss of migration in monarch butterflies

2019 ◽  
Vol 116 (29) ◽  
pp. 14671-14676 ◽  
Author(s):  
Ayşe Tenger-Trolander ◽  
Wei Lu ◽  
Michelle Noyes ◽  
Marcus R. Kronforst
Keyword(s):  
North American ◽  
Indoor Environment ◽  
Captive Breeding ◽  
Danaus Plexippus ◽  
Monarch Butterfly ◽  
Population Recovery ◽  
Monarch Butterflies ◽  
Commercial Population ◽  
Open Question ◽  
The Impact

The annual migration of the monarch butterfly Danaus plexippus is in peril. In an effort to aid population recovery, monarch enthusiasts across North America participate in a variety of conservation efforts, including captive rearing and release of monarch butterflies throughout the summer and autumn. However, the impact of captive breeding on monarchs remains an open question. Here, we show that captive breeding, both commercially and by summertime hobbyists, causes migratory behavior to be lost. Monarchs acquired commercially failed to orient south when reared outdoors in the autumn, unlike wild-caught North American monarchs, yet they did enter reproductive diapause. The commercial population was genetically highly divergent from wild-caught North American monarchs and had rounder forewings, similar to monarchs from nonmigratory populations. Furthermore, rearing wild-caught monarchs in an indoor environment mimicking natural migration-inducing conditions failed to elicit southward flight orientation. In fact, merely eclosing indoors after an otherwise complete lifecycle outdoors was enough to disrupt southern orientation. Our results provide a window into the complexity—and remarkable fragility—of migration.

scholarly journals Phylogenetic incongruence and the origins of cardenolide-resistant forms of Na+, K+- ATPase in North American Danaus butterflies

2016 ◽  
Author(s):  
Matthew L. Aardema ◽  
Peter Andolfatto
Keyword(s):  
North American ◽  
Host Plants ◽  
Incomplete Lineage Sorting ◽  
Danaus Plexippus ◽  
Orthologous Gene ◽  
Transcriptome Data ◽  
Lineage Sorting ◽  
Rapid Radiation ◽  
Sodium Potassium ◽  
Phylogenetic Incongruence

AbstractRapid species radiations can obscure phylogenetic relationships between even distantly related species and lead to incorrect evolutionary inferences. For this reason, we examined evolutionary relationships among the three North American milkweed butterflies, Danaus plexippus, D. gilippus and D. eresimus using >400 orthologous gene sequences assembled from transcriptome data. Contrary to previous phylogenetic assessments, our results indicate that D. plexippus and D. eresimus are the sister taxa among these species. This result explains many previously noted phylogenetic incongruences such as an amino acid substitution in the sodium-potassium pump (Na+,K+-ATPase) of D. eresimus and D. plexippus, which increases resistance to the toxins found in these butterflies’ host plants. In accordance with a rapid radiation of Danaus butterflies, we also find evidence that both incomplete lineage sorting and post-speciation genetic exchange have contributed significantly to the evolutionary histories of these species. Furthermore, our findings suggest that D. plexippus is highly derived both morphologically and behaviorally.

scholarly journals Changes in the geomagnetic field has little effect on the overwintering range of Eastern North American fall migratory monarch butterflies (Danaus plexippus), indicating a lack of an innate magnetic map sense for navigation

2020 ◽  
Author(s):  
Patrick Anthony Guerra ◽  
Stephen Matter
Keyword(s):  
Magnetic Field ◽  
North American ◽  
Geomagnetic Field ◽  
Danaus Plexippus ◽  
Monarch Butterfly ◽  
Central Mexico ◽  
Earth’S Magnetic Field ◽  
Long Distance ◽  
Monarch Butterflies ◽  
Earth's Magnetic Field

Abstract BackgroundIndividuals of many species that perform annual long-distance migrations are capable of stopping at specific overwintering destinations, despite having not been there before. The iconic monarch butterfly (Danaus plexippus) and its annual long-distance fall migration is a famous example of this phenomenon. During the fall, Eastern North American monarch butterflies use various compass mechanisms to properly orient their flight southwards, in order to leave their summer breeding grounds in Southern Canada and the Northern United States, and reach their overwintering sites in Central Mexico. It remains a mystery, however, how monarchs locate and stop at these specific, consistent overwintering sites, especially since these individuals are on their maiden voyage. MethodsWe test the hypothesis that fall migrant monarchs locate these overwintering sites by using an innate, inherited map sense based on sensing and responding to specific geomagnetic signatures that are correlated with the overwintering sites. Using a natural displacement approach, we examined if the locations of overwintering sites and the abundance of monarchs at them, changes with the natural shift of the Earth’s magnetic field over time (2004-2018).ResultsWe found that despite the natural displacement of the geomagnetic field over the years, the locations of the overwintering sites and monarch abundance were unaffected. For example, fall monarchs continued to overwinter at the most southern sites in Mexico, even when the geomagnetic coordinates associated with these sites would have shifted north due to the natural shift of the Earth’s magnetic field, placing these sites significantly outside the range of the overwintering area.ConclusionsOur results suggest that monarchs do not employ a map sense based on geomagnetic cues for finding their overwintering sites, and might instead use other mechanisms or strategies for locating them (potentially using localized sensory cues) once they are near or have arrived in Central Mexico. We suggest that future work should now focus on understanding what these cue parameters are, in order to inform conservation efforts that are aimed at protecting the threatened monarch butterfly and preserving its annual long-distance migration.

Sign in / Sign up

Export Citation Format

Share Document