Survival of Fall Monarch (Danaus plexippus) and Queen (Danaus gilippus) Butterfly Eggs and Larvae in North Texas

Document Type


Degree Name

Master of Science (MS)


Biological and Environmental Sciences

Date of Award

Spring 2019


The eastern population of the monarch butterfly (Danaus plexippus) has experienced declines over the last 25 years that have caused concern for the preservation of the species. Eastern monarchs reproduce through a series of four or five successive generations across most of the U.S. east of the Rocky Mountains. Currently, there is no existing data on monarch fifth generation survival, knowledge which could be important in increasing the size of the overwintering population. Data collection on fall monarch reproduction is complicated by the co-occurrence of queen butterflies (Danaus gilippus), potential competitors whose eggs are not readily distinguishable from those of monarchs in the field. Fall monarch and queen survivorship was calculated and assessed for any relationship with two environmental variables: the plant arthropod community and red imported fire ant (Solenopsis invicta) (RIFA) density. Survivorship was high, demonstrating the potential contribution of fifth generation fall monarchs. Jumping spiders (family Salticidae) had a significant negative effect on monarch and queen survival, while milkweed specialist herbivores and ants other than RIFA had significant positive effects. There was no statistically significant relationship between survivorship and RIFA density. Queen abundance had no negative effect on monarch survivorship despite their co-occurrence. Managing for fall fifth generation monarchs by generating high diversity habitats would aid in the recovery of the eastern monarch.


Jeff G. Kopachena

Subject Categories

Ecology and Evolutionary Biology | Life Sciences