Biodiversity Commons^™

Mathematically Modeling How Trapping Regimes That Target Specific Crayfish Life Stages Impact Removal Efficacy, Rini Pattison

Seaver College Research And Scholarly Achievement Symposium

The red swamp crayfish, Procambarus clarkii, is an invasive species introduced into several streams within the Santa Monica Mountains (SMM) in Southern California. Crayfish predation decimates native aquatic species. Thus, the Mountains Restoration Trust (MRT) and Environmental Restoration Group have worked to remove crayfish through regular trapping in Malibu Creek.

To aid conservation efforts, former SURB students William Milligan and Dev Patel developed mathematical models of crayfish removal efficacy. Milligan created a differential equation model of how crayfish removal affects local newt populations. Patel expanded Milligan’s crayfish model by creating a discrete model of the crayfish life cycle that newly …

Drone Imagery Of Submarine Groundwater Discharge Effects On Coastal Primary Productivity On Coral Reefs In Maunalua Bay, Hawai'i, Lulu Wang, Florybeth Flores La Valle, Grace Kim

Seaver College Research And Scholarly Achievement Symposium

Submarine groundwater discharge (SGD) plays a crucial role in coastal ecosystems, especially coral reefs, by introducing terrestrial nutrients and freshwater, significantly affecting the primary productivity of coastal ecosystems and potentially altering ecological balances. La Valle et al. (2023) emphasized the importance of SGD in nutrient distribution and algal productivity, highlighting the need for comprehensive understanding and management strategies in the face of increasing nutrient runoff due to land use changes due to increased population. To better understand the impact, our experiments utilize remote sensing and data science by using a DJI Mavic 3 Enterprise drone with a thermal imaging camera …

Effectiveness Of Frog Skin Secretions Against Uv-B Radiation, Connor Mcgaha, Kinkade Mcmurray, Lee B. Kats

Seaver College Research And Scholarly Achievement Symposium

As an increasing number of their species face possible extinction, amphibian populations have been steadily declining over the past decades (IUCN). While various factors have been suggested or proven to be partially responsible for this reduction, increased ultraviolet B radiation (UVBR) appears to be one of the more prominent explanations, especially when considering the continual thinning of the Earth’s ozone layer due to anthropogenic climate change. However, it has also been discovered that skin secretions, which are reported to function as a component of amphibians’ innate immune systems, may have an effect on UVBR (Cramp and Franklin). With this in …

A Natural Experiment Identifies An Impending Ecological Trap For A Neotropical Amphibian In Response To Extreme Weather Events, Morgan A. Clark, William M. Ota, Sierra J. Smith, Brett K. Muramoto, Summer Ngo, Gabriella E. Chan, Maxwell A. Kenyon, Matthew C. Sturtevant, Max G. Diamond, Gary M. Bucciarelli, Lee B. Kats

All Faculty Open Access Publications

Extreme weather events are predicted to increase as a result of climate change, yet amphibian responses to extreme disturbance events remain understudied, especially in the Neotropics. Recently, an unprecedented windstorm within a protected Costa Rican rainforest opened large light gaps in sites where we have studied behavioral responses of diurnal strawberry poison frogs (Oophaga pumilio) to ultraviolet radiation for nearly two decades. Previous studies demonstrate that O. pumilio selects and defends perches where ultraviolet radiation (UV-B) is relatively low, likely because of the lethal and sublethal effects of UV-B. In this natural experiment, we quantified disturbance to O. pumilio habitat, …

Effectiveness Of Plastic Ordinances In Santa Monica, Ca: Do Regulations At The Municipal Level Reduce Plastic Waste?, John W. Hayes

School of Public Policy Capstones

Plastic is a cheap, robust and versatile material with numerous practical uses that contribute to the convenience of modern day life. However the very same properties that make it uniquely diverse and hardy also contribute to the hazards it poses to the ecosystems and human health. If current consumption and manufacturing practices remain unchanged, there will be hundreds of millions of additional tons of plastic introduced into the environment over the coming decades. To mitigate this issue, some cities, such as Santa Monica, have implemented ordinances and policies directly aimed at this growing problem, albeit with ambiguous results. To better …

Decline In Amphibian Health In Local Stream, Elyse Vetter, Elise Dearment, Colton Russell, Audrey Fontes, Lee Kats

Seaver College Research And Scholarly Achievement Symposium

Many local streams of the Santa Monica Mountains are populated by the native California Newt, Taricha torosa, a species of special concern. Arroyo Sequit is one of these streams, the upper and lower portions of which are split by a culvert and the Mulholland Highway. This stream and the surrounding areas burned during the Woolsey fire of 2018. Since the fire, construction has been ongoing in and around the stream. Two years post-fire (during the summer of 2020) significantly more newts were found in the stream than years prior. A large proportion of these newts were unhealthy in appearance, …

Conspecific Aggression Of Invasive Crayfish, P. Clarkii, In Response To Chemical Cues, Elyse Vetter, Elise Dearment, Audrey Fontes, Gary Bucciarelli, Lee Kats

Seaver College Research And Scholarly Achievement Symposium

Red Swamp Crayfish, Procambarus clarkii, have caused vast damage to the stream ecosystem of the Santa Monica Mountains, following their invasive introduction. Through their extensive eating habits, high levels of aggression, and responsiveness to environmental stimuli, P. clarkii have a tremendous impact on the success of native species in the Santa Monica Mountains. With exposure to chemical cues, crayfish are able to perceive threats and react accordingly. To determine the extent of such chemoreception, pairs of P. clarkii were tested in the laboratory for conspecific aggression in the presence of native newt, native frog, and conspecific alarm cues. The …

The Effects Of Symbiote Ostracods On Invasive Crayfish Behavior, Audrey Fontes, Elyse Vetter, Gary Bucciarelli, Lee Kats

Seaver College Research And Scholarly Achievement Symposium

Invasive crayfish, Procambarus clarkii, are known to negatively impact the biodiversity of Santa Monica Mountain streams. Small symbiotes, ostracods, live on Procambarus clarkii in some local streams. However, their effect on the behaviour of invasive crayfish is unknown. We used an aqueous chlorobutanol solution to remove ostracods from crayfish. We paired control crayfish with those that had ostracods removed and scored aggressive interactions. Crayfish without ostracods were found to be significantly more aggressive towards crayfish with ostracods. When we compared feeding behavior, we found that crayfish without ostracods consumed food more quickly than control crayfish. We again subjected crayfish …

Federal V. State Effectiveness: An Analysis Of The Endangered Species Act And Current Potential Attempts At Reform, Nicholas Primo

Pepperdine Policy Review

In November 2013, several Congressional leaders drafted a new bill to reform the Endangered Species Act of 1973 (ESA). While the Endangered Species Management Self-Determination Act (ESMSDA) was the first major attempt at updating the crucial U.S. environmental policy in decades, it also inflamed environmentalist defenders of the original bill. More importantly, it raised several questions as to whether state or federal-oriented approaches to endangered species protection and environmental policy more broadly is ultimately more effective. This article analyzes the original 1973 ESA, followed by an analysis of the ESMSDA currently being considered. It will discuss the various strengths and …