Observations by farahf

Scientific & Common Name(s):
Danaus plexippus, commonly known as the Monarch butterfly, is a captivating and colourful insect that is typically found in North America (National Geographic, n.d.).

Habitat & Geographic Range:
Monarch butterflies inhabit a broad geographic area, the various countries that they are found in are Canada, America, and Mexico (Pleasants & Oberhauser, 2012). Mainly spanning from south of Canada to regions in the south of America, these butterflies can be found on both the west and east coasts of North America (Pleasants & Oberhauser, 2012). However, most eastern monarchs are known for their ability to migrate and therefore depending on their season and stage of life; their habitats can alter (Pleasants & Oberhauser, 2012). Monarchs are found on milkweeds during the larval stages; adult monarchs can be found in open fields where nectar is plentiful and on different types of trees in their specific winter locations (Brower, Fink & Walford, 2006).

Size /Weight & Lifespan:
The size and weight of monarch butterflies are found to be sexually dimorphic traits in these species (Davis & Holden, 2015). Research has shown that male monarchs have a larger and greater body size with an average weight of 588 mg in contrast to female monarchs, which weigh 531 mg (Davis & Holden, 2015). Similarly to other insects, the monarch butterfly goes through four stages of development (National Geographic, n.d.). Beginning as an egg, then developing into larvae, which is followed by the pupal stage, and finally emerging into the adult butterfly (National Geographic, n.d.). With that, the average lifespan of a monarch is approximately six to eight months long (National Geographic, n.d.).

Diet:
Throughout the distinctive stages of life, the monarch butterfly alters their diet depending on their energy demands at each stage (Brower, Fink & Walford, 2006). In the larval stage, larvae typically feed on milkweeds in agricultural fields for development (Pleasants & Oberhauser, 2012). Milkweeds have a toxic component that acts as a defense mechanism against predators (Mebs, Wunder, Pogoda & Toennes, 2017). When they emerge as adults, they feed on the nectar of plants, which is then converted to and stored as lipids in their bodies to fuel them with enough energy for the long migratory routes (Brower, Fink & Walford, 2006).

Reproduction & Communication:
Monarch butterflies tend to mate in the spring season before colder climate approaches (Batalden, Oberhauser & Peterson, 2007). Typically male butterflies will release chemical cues to communicate with a mate (Solensky, 2004). However, monarch butterflies tend to focus less on chemical signals; mating between monarchs involves two stages (Solensky, 2004). First, the male finds a female in the air and takes hold of her (Solensky, 2004). Secondly, he aggressively pushes the female to the ground in an attempt to mate (Solensky, 2004). Furthermore, research has shown that males use the colour of their wings as a signal to communicate with a mate (Davis, Cope, Smith & Solensky, 2007). It was found that males with a higher saturation of the orange colouration have a greater mating success (Davis, Cope, Smith & Solensky, 2007). With that, the colour orange serves as a multipurpose function on monarchs; it is used as a danger signal to predators to show that they are toxic species (Jeffords, Sternburg & Waldbauer, 1979).

Predation: Does the animal have any predators?
Monarch butterflies display the orange coloration as a defense mechanism and as a signal to predators that they are toxic (Jeffords, Sternburg & Waldbauer, 1979). However, species such as birds, mice, and the praying mantis are predators of the monarch, regardless of the fact that there are harmful components that accompany the consumption of the milkweed from the monarch's diet (Brower & Calvert,1985; Brower, Horner, Marty, Moffitt, & Bernardo Villa-R,1985; Mebs, Wunder, Pogoda & Toennes, 2017).

Conservation Status:
Certain factors can have an impact on a group of organisms and species, in the way they act and live and therefore playing a role in the risk of extinction. Monarch butterflies in North America are considered as vulnerable and imperiled species because of factors such as the decrease in agriculture, climate change, and deforestation (Jepsen et al., 2015).

Did you know that monarchs can migrate up to forty thousand kilometers to reach warmer regions during the winter season (Zhan, Merlin, Boore & Reppert, 2011)?

Reference List

Batalden, R., Oberhauser, K., & Peterson, A. (2007). Ecological Niches in Sequential Generations of Eastern North American Monarch Butterflies (Lepidoptera: Danaidae): The Ecology of Migration and Likely Climate Change Implications. Environmental Entomology, 36(6), 1365-1373. http://dx.doi.org/10.1603/0046-225x(2007)36[1365:enisgo]2.0.co;2

Brower, L., & Calvert, W. (1985). Foraging Dynamics of Bird Predators on Overwintering Monarch Butterflies in Mexico. Evolution, 39(4), 852-868. doi:10.2307/2408685

Brower, L., Horner, B., Marty, M., Moffitt, C., & Bernardo Villa-R. (1985). Mice (Peromyscus maniculatus, P. spicilegus, and Microtus mexicanus) as Predators of Overwintering Monarch Butterflies (Danaus plexippus) in Mexico. Biotropica, 17(2), 89-99. doi:10.2307/238850

Brower, L., Fink, L., & Walford, P. (2006). Fueling the fall migration of the monarch butterfly. Integrative And Comparative Biology, 46(6), 1123-1142. http://dx.doi.org/10.1093/icb/icl029

Davis, A., Cope, N., Smith, A., & Solensky, M. (2007). Wing Color Predicts Future Mating Success in Male Monarch Butterflies. Annals Of The Entomological Society Of America, 100(2), 339-344. http://dx.doi.org/10.1603/0013-8746(2007)100[339:wcpfms]2.0.co;2

Davis, A., & Holden, M. (2015). Measuring Intraspecific Variation in Flight-Related Morphology of Monarch Butterflies (Danaus plexippus): Which Sex Has the Best Flying Gear?. Journal of Insects, vol. 2015, Article ID 591705, 6 pages. doi:10.1155/2015/591705

Jeffords, M., Sternburg, J., & Waldbauer, G. (1979). Batesian Mimicry: Field Demonstration of the Survival Value of Pipevine Swallowtail and Monarch Color Patterns. Evolution, 33(1), 275-286. doi:10.2307/2407618

Jepsen, S., Shweitzer, D.F, Young, B., Sears, N., Ormes, M., & Black, S.H. (2015). Conservation Status and Ecology of the Monarch Butterfly in the United States. Retrieved from http://www.natureserve.org/sites/default/files/natureserve-xerces_monarchs_usfs-final.pdf

Mebs, D., Wunder, C., Pogoda, W., & Toennes, S. (2017). Feeding on toxic prey. The praying mantis (Mantodea) as predator of poisonous butterfly and moth (Lepidoptera) caterpillars. Toxicon, 131, 16-19. http://dx.doi.org/10.1016/j.toxicon.2017.03.010

National Geographic. (n.d.). Monarch Butterfly. Retrieved from https://www.nationalgeographic.com/animals/invertebrates/m/monarch-butterfly/

Pleasants, J., & Oberhauser, K. (2012). Milkweed loss in agricultural fields because of herbicide use: effect on the monarch butterfly population. Insect Conservation And Diversity, 6(2), 135-144. doi: 10.1111/j.1752-4598.2012.00196.x

Solensky, M. (2004). The Effect of Behavior and Ecology on Male Mating Success in Overwintering Monarch Butterflies (Danaus plexippus). Journal Of Insect Behavior, 17(6), 723-743. http://dx.doi.org/10.1023/b:joir.0000048985.58159.0d

Zhan, S., Merlin, C., Boore, J., & Reppert, S. (2011). The Monarch Butterfly Genome Yields Insights into Long-Distance Migration. Cell, 147(5), 1171-1185. http://dx.doi.org/10.1016/j.cell.2011.09.052