Aphid colony on Ligusticum inflorescence (Photo by J. Den Uyl)
Phenological Drivers of Herbivore Abundance
We have monitored arthropod abundance in ten Ligusticum porteri (osha) populations near the Rocky Mountain Biological Laboratory for the last ten years.
From these data, we see that yearly variation in the abundance of aphids (Aphis asclepiadis) is associated with the timing of snow melt in spring. Through several experiments, we found that this is due to changes in both predators and in host plants. When snowmelt comes later, soils stay moist and prevent drought stress in the host plant. Drought stressed plants show several signals of lower quality for aphid colony growth. When snowmelt comes earlier, plants are drought stressed and key aphid predators surge in abundance. Predator presence can drive aphid colonies to extinction. The major predator we observe are Lygus bugs, which also create changes in host plants that aphids can detect. Overall, our NSF-sponsored research shows the many ways that changing snow duration is shaping herbivore abundance.
We have monitored arthropod abundance in ten Ligusticum porteri (osha) populations near the Rocky Mountain Biological Laboratory for the last ten years.
From these data, we see that yearly variation in the abundance of aphids (Aphis asclepiadis) is associated with the timing of snow melt in spring. Through several experiments, we found that this is due to changes in both predators and in host plants. When snowmelt comes later, soils stay moist and prevent drought stress in the host plant. Drought stressed plants show several signals of lower quality for aphid colony growth. When snowmelt comes earlier, plants are drought stressed and key aphid predators surge in abundance. Predator presence can drive aphid colonies to extinction. The major predator we observe are Lygus bugs, which also create changes in host plants that aphids can detect. Overall, our NSF-sponsored research shows the many ways that changing snow duration is shaping herbivore abundance.
Facultative Mutualism in a Rare Colorado Butterfly
In summer of 2020, we began work in a new system along Monument Creek near Colorado Springs! This work is in collaboration with Robert Schorr from the Colorado Natural Heritage Program.
Caterpillars of the rare butterfly Celastrina humulus occur on the male flowers of our native hops plant, Humulus lupulus var. neomexicanus. The hops plants are dioecious, meaning that they have both male and female flowers. The caterpillars also can form a mutualism with ants. Ants seem to protect the larvae from predators while the larvae provide a reward from their dorsal nectary organs. However, this association appears to be facultative, that is, found in some areas but not others. We are looking broadly at what factors lead to this association in some areas but not in others. We also collected samples of the larval reward for chemical analysis.
In summer of 2020, we began work in a new system along Monument Creek near Colorado Springs! This work is in collaboration with Robert Schorr from the Colorado Natural Heritage Program.
Caterpillars of the rare butterfly Celastrina humulus occur on the male flowers of our native hops plant, Humulus lupulus var. neomexicanus. The hops plants are dioecious, meaning that they have both male and female flowers. The caterpillars also can form a mutualism with ants. Ants seem to protect the larvae from predators while the larvae provide a reward from their dorsal nectary organs. However, this association appears to be facultative, that is, found in some areas but not others. We are looking broadly at what factors lead to this association in some areas but not in others. We also collected samples of the larval reward for chemical analysis.
Confluence of Fountain Creek and Arkansas River (Photo by J. Beall)
This PFCs in Fountain Creek Riparian Food Webs
We are examining the movement of PFCs through riparian food webs. This work was funded by 2018 LAS Dean’s Research Initiative: Environmental PFC Impact Collaboration (EPIC) in the Fountain Creek Watershed: Determining the Environmental, Ecological, and Societal Impact of PFCs. Projects are assessing the extent to which these compounds move through trophic levels (plants-herbivores-carnivores) in the field and laboratory. We are using a combination of observational and experimental approaches. This will include sampling riparian food webs in the field, and rearing model food webs in laboratory growth chambers.
We are examining the movement of PFCs through riparian food webs. This work was funded by 2018 LAS Dean’s Research Initiative: Environmental PFC Impact Collaboration (EPIC) in the Fountain Creek Watershed: Determining the Environmental, Ecological, and Societal Impact of PFCs. Projects are assessing the extent to which these compounds move through trophic levels (plants-herbivores-carnivores) in the field and laboratory. We are using a combination of observational and experimental approaches. This will include sampling riparian food webs in the field, and rearing model food webs in laboratory growth chambers.
Freshly harvested Ligusticum roots
Ecological Determinants of Medicinal Activity
Humans depend on medicinal plants. Many people still rely on traditional herbal medicine and pharmaceutical drug discovery also uses the compounds found in nature. Plant defense theory predicts that plants in certain environments will be better defended than plants. The same chemicals that humans recognize for their medicinal benefits are often those that plants use to defend themselves against herbivores. We collaborate with analytical chemists from the UCCS Department of Chemistry to assess this variation. Our research found distinct chemotypes between Ligusticum porteri roots collected on the Front Range versus the Western Slope of Colorado. Read about it here.
Humans depend on medicinal plants. Many people still rely on traditional herbal medicine and pharmaceutical drug discovery also uses the compounds found in nature. Plant defense theory predicts that plants in certain environments will be better defended than plants. The same chemicals that humans recognize for their medicinal benefits are often those that plants use to defend themselves against herbivores. We collaborate with analytical chemists from the UCCS Department of Chemistry to assess this variation. Our research found distinct chemotypes between Ligusticum porteri roots collected on the Front Range versus the Western Slope of Colorado. Read about it here.
Course-Based Undergraduate Research
Real-world research experiences are fully incorporated into two courses at UCCS: BIOL 4460 Methods in Field Ecology and BIOL 3750 Conservation Biology. These include long-term monitoring efforts where classes contribute data to larger projects. Students have the opportunity to present their research at regional conferences such as the Front Range Student Ecology Symposium and the Colorado Undergraduate Research Forum.
Real-world research experiences are fully incorporated into two courses at UCCS: BIOL 4460 Methods in Field Ecology and BIOL 3750 Conservation Biology. These include long-term monitoring efforts where classes contribute data to larger projects. Students have the opportunity to present their research at regional conferences such as the Front Range Student Ecology Symposium and the Colorado Undergraduate Research Forum.