7 Works

Effects of volatile compounds in California bay trees (Umbellularia californica) on vegetation growth and insect herbivory

Ashley Adornato, Hannah Gerber, Sarah Haas & Jennifer Perez
Secondary metabolites are volatile compounds produced by plants that can be used as defense mechanisms for reducing stressors such as herbivory and competition. Leaves, roots, and stems of California bay trees (Umbellularia californica) get their notable aroma from secondary metabolites called monoterpenes, which are allelopathic constituents in many other plants, such as eucalyptus. In this study, we investigated the potential allelopathic and anti-herbivory effects of California bay trees by examining their understory composition, germination rates...

Bird community interactions at water sources at Hastings Natural History Reservation

Christina Cen, Killian Fay, Joselyne Jaramillo & Jason Ku
In seasonally dry areas, artificial water sources become a gathering place for a variety of avian species, leading to interactions between birds whose niches otherwise do not overlap. To maximize water use while reducing negative costs associated with conflict and predation, birds adopt anti-predation behaviors and engage in differing levels of tolerant and conflict interactions. In order to better understand how birds interact and behave at artificial water resources, we examined whether species and flock...

Factors affecting woodrat abundance over 70 years

Wolfgang Abad, Jose Morales-Doo, Carly Pomeroy & Adrienne Ung
Woodrats are ecosystem engineers that can increase biodiversity by physically changing the environment. In doing so, they alter landscapes and increase the number of microhabitats for other organisms. In order to better understand woodrats’ role in their ecosystem, we surveyed big-eared woodrat (Neotoma macrotis) houses in Hastings Natural History Reservation located in Monterey County, California. For each house, we determined its usability and measured its size. We found a 26 percent increase in population density...

Acorn woodpeckers (Melanerpes formicivorus) exhibit more predator avoidance behavior post-fire

Emily Drake, , Youssef Hanna & Johnson Ku
Climate change has increased the frequency of wildfires globally. This increase in wildfires causes many animals to adjust their behaviors in order to cope with the more regular disturbances occurring in their habitats. It is often thought that birds are less affected by disturbances such as fire because of their ability to easily relocate by flying, but species with high levels of territoriality, such as acorn woodpeckers (Melanerpes formicivorus), may be more greatly affected by...

The effects of plant and epiphyte interactions on bark exfoliation in Arbutus menziesii

Sheena Cabal, Gavin Kellerman & Shannon McKillop-Herr
Bark provides trees with many important functions, such as nutrient transport and protection, yet the Pacific madrone (Arbutus menziesii) regularly exfoliates its bark. The mechanism for this exfoliation is largely unknown, but is possibly due to biotic pressures, such as epiphyte or poison oak (Toxicodendron diversilobum) growth, or abiotic pressures, like solar radiation exposure. In order to test potential drivers of shedding, we surveyed 49 madrones and neighboring oaks at Hastings Natural History Reserve. For...

Factors affecting acorn predation and infestation in three California oaks

Nicolette Balmaceda, Jovana Durovic, Sierra Montes & Kyler Plouffe
Oak woodlands are in decline due to failed oak recruitment in California. Oak recruitment is heavily impacted by vertebrate herbivory and insect infestation of acorns. Oaks have developed chemical defenses such as tannins to protect acorns from attack. Studies have explored infestation differences in red oaks but have not compared infestation between red oaks and white oaks. We explored how Cydia latiferreana (filbertworm) infestation, Curculio occidentalis (filbert weevil) infestation, and Sciurus griseus nigripes (western gray...

Investigating unburned understory “halos” post-fire under blue oak (Quercus douglasii) canopies

Skyler Bennis, Sam Cormier, Angela Ma & Madeline Perreault
Oak trees profoundly impact California’s oak landscape biodiversity. Oaks influence growth in their understories and these community interactions have important ecological implications. Oaks can facilitate (positive) or interfere (negative) with understory productivity depending on tree characteristics such as variation in root morphology. Historically, California oak communities have been negatively affected by fire suppression, but they are now being impacted by increasing wildfire frequency. Despite their dominance in the woodland and savanna landscapes, there is a...

Registration Year

  • 2020

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