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Milkweed loss in agricultural fields because of herbicide use: effect on the monarch butterfly population
Abstract.  1. The size of the Mexican overwintering population of monarch butterflies has decreased over the last decade. Approximately half of these butterflies come from the U.S. Midwest whereExpand
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Impact of Bt corn pollen on monarch butterfly populations: A risk assessment
A collaborative research effort by scientists in several states and in Canada has produced information to develop a formal risk assessment of the impact of Bt corn on monarch butterfly (DanausExpand
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Milkweed restoration in the Midwest for monarch butterfly recovery: estimates of milkweeds lost, milkweeds remaining and milkweeds that must be added to increase the monarch population
The loss of milkweeds in corn and soybean fields in the Midwest due to herbicide use has been implicated in the decline of the monarch butterfly population. In order to gauge the magnitude of theExpand
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Restoring monarch butterfly habitat in the Midwestern US: ?all hands on deck?
The eastern migratory population of monarch butterflies (Danaus plexippus plexippus) has declined by >80% within the last two decades. One possible cause of this decline is the loss of ≥1.3 billionExpand
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Nectar production patterns in Ipomopsis aggregata (Polemoniaceae).
This study describes nectar production patterns for Ipomopsis aggregata and discusses their potential adaptive and ecological significance. It also examines the influence of environmental and otherExpand
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Quasi-extinction risk and population targets for the Eastern, migratory population of monarch butterflies (Danaus plexippus)
The Eastern, migratory population of monarch butterflies (Danaus plexippus), an iconic North American insect, has declined by ~80% over the last decade. The monarch’s multi-generational migrationExpand
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COMPETITION FOR BUMBLEBEE POLLINATORS IN ROCKY MOUNTAIN PLANT COMMUNITIES
Meadow plant communities at four sites in the Colorado Rocky Mountains were stud- ied to evaluate the influence of competition for bumblebee pollinators. The niche relationships among plant speciesExpand
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Monarch butterfly population decline in North America: identifying the threatening processes
The monarch butterfly (Danaus plexippus) population in North America has sharply declined over the last two decades. Despite rising concern over the monarch butterfly's status, no comprehensive studyExpand
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Interpreting surveys to estimate the size of the monarch butterfly population: Pitfalls and prospects
To assess the change in the size of the eastern North American monarch butterfly summer population, studies have used long-term data sets of counts of adult butterflies or eggs per milkweed stem.Expand
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Density estimates of monarch butterflies overwintering in central Mexico
Given the rapid population decline and recent petition for listing of the monarch butterfly (Danaus plexippus L.) under the Endangered Species Act, an accurate estimate of the Eastern, migratoryExpand
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