About This Project

Caterpillars are a popular prey item for birds, mammals and insects and are widely used for predator-prey interaction studies. Pandora & Achemon Sphinx moth larvae found in MA have multiple color morphs: green, red, orange and brown. Yet, they are assumed to be palatable to predators. The larvae have conspicuous splotch markings on their sides but the functionality of these markings have not been explored. I will utilize artificial prey to see if coloration & patterning affect predation risk.

Ask the Scientists

What is the context of this research?

Predator-prey interactions are important to study as vertebrate and invertebrate predators can control and regulate prey populations. As a common prey item, caterpillars have evolved many morphological, chemical, and behavioral defensive strategies including crypsis, mimicry, masquerading, and aposematism (Skelhorn et al., 2010). Scientists suggest that caterpillar colors and patterns are cryptic, to decrease visual detectability or aposematic, to increase conspicuousness and warn a predator they are toxic. These defenses affect predation of different predators. Using model prey, we can gain a greater understanding of how potential predators may be attracted or deterred by coloration or patterning of prey (Low et al., 2014, Howe et al., 2009).

What is the significance of this project?

Previously, artificial caterpillar prey has been used to assess how size, coloration, body position and eyespots affect predation risk in various habitats around the world, and, as such, can be extremely valuable for broad-scale comparative studies (Hossie & Sherratt, 2013, Suzuki & Sakurai, 2015). Eumorpha larvae have multiple color morphs but are assumed to be non-toxic to predators. Also, rather than having 2 eyespots to mimic a snake or larger animal, the larvae have 5-6 splotch markings on their sides. Are the splotch markings effective in deterring predation? My project will contribute to our understanding of how coloration and patterning may affect predation risk in suburban forests in Massachusetts.

What are the goals of the project?

The aims of this study are to 1) test if there is a color morph (green or red) that is more heavily predated upon 2) test if the presence of lateral white/yellow splotches is effective in reducing predation risk 3) identify insectivorous bird species abundance in all three sites through periodic bird point count surveys and 4) assess if predation pressures from different taxonomic groups fluctuate throughout the season (early summer to early fall, July through September). Through the use of camera traps, I will potentially be able to identify predators to the species level and the images may also provide insight on the diel timing of predation. The images will also increase accessibility and understandability when sharing results with the general public.