Ecology and Evolutionary Biology Commons^™

Effects Of Soil Erosion Barriers On Percent Cover And Sediment Size, Michael Perez

STAR Program Research Presentations

Ranching began on Santa Rosa Island in the 1840’s, introducing nonnative megafauna that put selective grazing pressures on endemic species. Dense groves of island oak (Q. tomentella) are aid in sediment deposition and retention. A current restoration effort, involved installing soil erosion barriers, known as wattles, to prevent sediment from being lost upslope and recruit plant growth whose root systems could further stabilize the slope. This experiment was designed to compare percent cover of vegetation growth in areas with and without soil erosion barriers. This was done using the line intercept method (n=42) on three meter transects, measuring …

The Effectiveness Of Periodically-Harvested Closures In Meeting Ecological And Socioeconomic Objectives, Paul G. Carvalho

Master's Theses

Periodically-harvested fisheries closures (PHCs) are a widespread form of community-based marine spatial management used throughout the Indo-Pacific that also is currently being intensively advocated by conservation organizations for supporting productive fisheries and healthy marine ecosystems. However, local implementation of PHCs has historically been designed to support occasional and efficient exploitation of fish stocks, and not necessarily sustainable fisheries yields and stock conservation. The efficacy of PHCs for achieving their historical cultural objectives of periodicity and efficiency of harvest, simultaneously with achieving contemporary fisheries objectives of fisheries productivity and conservation is undetermined. As a result, the utility of PHCs for supporting …

Effects Of Experimental Noise Exposure On Songbird Nesting Behaviors And Nest Success, Tracy I. Mulholland

Master's Theses

Anthropogenic noise is an increasingly prevalent global disturbance. Animals that rely on the acoustical environment, such as songbirds, are especially vulnerable to these sounds. Traffic noise, in particular, overlaps with the frequency range of songbirds, creating masking effects. We investigated the effects of chronic traffic noise on provisioning behaviors and breeding success of nesting western bluebirds (Sialia mexicana) and ash-throated flycatchers (Myiarchus cinerascens). Because anthropogenic noise exposure has the potential to interrupt parent-offspring communication and alter vigilance behaviors, we predicted that traffic noise would lead to changes in provisioning behaviors, such as fewer visits to the …

The Preservation And Protection Of Native Biodiversity In The Guadalupe Nipomo Dunes Complex, Lindsey M. Whitaker, Matthew Ritter, Scott J. Steinmaus, Jonathan Hall

Master's Theses

The Guadalupe Nipomo Dunes Complex (GNDC) is located within the California Floristic Province, a biodiversity hotspot characterized by high rates of endemism and exceptional loss of habitat. In 1980, the US Fish and Wildlife Service described the GNDC as, “the most unique and fragile ecosystem in the State of California,” and ranked it first on a list of 49 habitat areas needing state protection. It is the largest coastal dune area in California and it is one of the last remaining, relatively intact ecosystems of its type and size in the western United States. The growing recognition of species decline …

Automated Detection Of Deep-Sea Animals, Dallas J. Hollis, Duane Edgington, Danelle Cline

STAR Program Research Presentations

The Monterey Bay Aquarium Research Institute routinely deploys remotely operated underwater vehicles equipped with high definition cameras for use in scientific studies. Utilizing a video collection of over 22,000 hours and the Video Annotation and Reference System, we have set out to automate the detection and classification of deep-sea animals. This paper serves to explore the pitfalls of automation and suggest possible solutions to automated detection in diverse ecosystems with varying field conditions. Detection was tested using a saliency-based neuromorphic selective attention algorithm. The animals that were not detected were then used to tune saliency parameters. Once objects are detected, …

Effect Of The 2013-2015 California Drought On Small Mammal Abundance And Diversity In Chaparral, Oak Woodland And Riparian Habitats, Nicole Desideri

Biological Sciences

Long-term biodiversity surveys are a useful tool for assessing the impacts of stochastic events on wildlife and their communities. A recent stochastic event to affect the state of California is the historic 2013-2015 drought. This drought, described as a one-in-one-thousand year event, brought precipitation to a historic low; the statewide rainfall reaching 34% below average (Swain et al. 2014). While humans are feeling the impact of this water shortage, the effects on native ecosystems and wildlife populations are poorly documented. Baseline small mammal biodiversity data collected in 2011, before the drought, allows us the opportunity to study the impacts of …

Evaluating The Myth Of Allelopathy In California Blue Gum Plantations, Kristen Marie Nelson

Master's Theses

It is widely accepted that allelopathy is not only significant, but more or less singular, in the inhibition of understory vegetation in California Eucalyptus globulus (blue gum) plantations. However, there is no published documentation of allelopathy by blue gums against California native species. Here, we present evidence that germination and early seedling growth of five California native species are not inhibited by chemical extracts of blue gum foliage, either at naturally-occurring or artificially concentrated levels. In the greenhouse, seeds were germinated in field-collected soil from mature blue gum plantations and the adjacent native, coastal scrub communities. In petri plates, seeds …

Native Deer Mice (Peromyscus Maniculatus) Use Of Invasive Grass Seed (Ehrharta Calycina) In Coastal California, Megan Wong

Biological Sciences

No abstract provided.

Mapping The Movement Of Overwintering Western Monarch Butterflies (Danaus Plexippus) At The Pismo Beach Monarch Butterfly Grove Using Arcgis Software, Brett Johnson, Jesse Wycko, Daniel Goldthwaite, Tyler Brown

Symposium

Dr. Villablanca of the Cal Poly Biology Department commissioned this project with the goal of tracking Monarch Butterfly spatial redistribution in anticipation of or response to severe weather events. We believe that Monarchs cluster non-preferentially on introduced Eucalyptus trees until midwinter when they begin to cluster preferentially on native conifers. Based on the efforts of a previous group of students, it has been deter- mined that, over a two-week time period in mid-winter, Monarchs spend the majority of their time on native conifers. We set out to clearly demonstrate Monarch Butterfly spatial redistribution in either anticipation of or response to …

An Invasive Grass And A Desert Adapted Rodent: Is There An Effect On Locomotory Performance And Is It Modified By Prior Experience Or Familiarization?, Camille D. Boag

Master's Theses

Kangaroo rats (Dipodomys spp.) are frequently characterized as keystone species for their role in altering soil characteristics, changing habitat structure through seed consumption and dispersal, and being important primary consumers in their ecosystem. They are arid adapted and known to forage in areas with sparse vegetation. Studies suggests densely vegetated habitat to be unsuitable for kangaroo rats because plants are an impediment to their locomotion and predator avoidance behaviors. This study focuses on an invasive grass, South African Veldt (Ehrharta calycina), that converts landscapes with sparse vegetation into dense grassland habitats, and the Lompoc kangaroo rat …

Effects Of Supplemental Hydration On Physiology And Behavior Of Northern Pacific Rattlesnakes (Crotalus Oreganus Oreganus), Griffin D. Capehart

Master's Theses

Hydration is a critical element for many physiological processes in vertebrates, such as protein production, innate immunity, and behavioral processes such as daily activity and thermoregulation. Few studies have directly assessed the effect of hydration on these animals in nature. While it seems intuitive that drought is stressful to animals, studies examining drought are typically observational and fail to assess how the hydration state of these animals influences their physiology and behavior. We tested for an effect of hydration on several physiological and behavioral parameters in Northern Pacific rattlesnakes (Crotalus oreganus oreganus) by experimentally manipulating hydration levels in …

Morphological Response In Sister Taxa Of Woodrats (Genus: Neotoma) Across A Zone Of Secondary Contact, Michaela M. Koenig

Master's Theses

This study focuses on a secondary contact zone between two sister species of woodrat, Neotoma fuscipes (dusky-footed woodrat) and N. macrotis (big-eared woodrat). Along the Nacimiento River, on the border of southern Monterey and northern San Luis Obispo counties, the ranges of these sister species of woodrats meet and overlap forming a secondary contact zone. The zone of secondary contact is estimated to include a 500-meter (~1,650 linear feet) portion of the Nacimiento River riparian corridor.

This research examines quantifiable morphological change that is likely associated with heightened inter-specific competition within the contact zone. When in sympatry the sister species …

How Are Rare Species Maintained?: Reproductive Barriers Between Layia Jonesii, A Rare Serpentine Endemic, And L. Platyglossa, Natalie L. Rossington

Master's Theses

Reproductive barriers are vital to generating new species as well as maintaining distinct species. Investigating reproductive barriers between closely related plant taxa helps us to understand how these barriers are maintained, particularly between rare and widespread relatives. Layia jonesii, a rare San Luis Obispo County serpentine endemic, and L. platyglossa, a common coastal species, co-occur on serpentine derived hillsides and are interfertile. At these locations, L. jonesii is isolated to dry soils near serpentine rock outcrops and L. platyglossa is located on slightly deeper grassland soils surrounding the rock outcrops. On hillsides where they co-occur, I observe two morphologically …

Sediment Loss Of Santa Rosa Island Slopes: An Erosional Study, Michael Perez

STAR Program Research Presentations

Ranching began on Santa Rosa Island in the 1840’s, consequently introducing nonnative megafauna that put novel selective grazing pressures on endemic plant species. Their movement patterns also altered sediment integrity as the land was denuded of any stabilizing vegetation. Dense groves of island oak (Q. tomentella) are known to aid in sediment deposition and retention. The groves also function to collect water during periods of intense fog that are common to the island. This experiment sought to quantify the volume of sediment that has been lost on a south facing slope in the middle of the island that …

Do Marine Protected Areas Affect Emerging Fisheries Population Density?, Jennifer Greene, Katherine O. Grady, Crow White, Danielle Zacherl

STAR Program Research Presentations

Kellet’s whelk, Kelletia kelletii, were observed at sample sites throughout their range from Baja California, Mexico, to Monterey, CA to determine patterns of population density. Sample sites in each region were either located within California marine protected areas where take of the Kellet’s whelk in prohibited, or in non-protected areas where the whelks can be fished both commercially and recreationally. Kellet’s whelk population density was compared between all MPA and non-MPA sample sites. These mean densities were also found for sites in Santa Barbara and San Diego near active fishing ports and compared to data from the same sites collected …

Performance Variation In Leptasterias Spp. Among Populations And Habitats, Caleb Shaw, Laura Melroy, Janet Bair, Sarah Cohen

STAR Program Research Presentations

Leptasterias spp. are six rayed sea stars that are found in rocky intertidal habitats ranging from the California coast to Alaska. In central California, Leptasterias spp. can be found in a variety of intertidal habitats in mixed populations. There are multiple clades that represent these populations and it is thought that they may vary behaviorally, including habitat preference. To investigate this individuals were collected from Pigeon Point, San Mateo, CA and characterized into two habitat categories according to where they were found: rocky habitat and pool habitat. To test for behavioral variation among habitats, righting response was used as a …

Monitoring Abundance Of Carcinus Maenas Developmental Stages In Seadrift Lagoon, Andrea M. Fieber

STAR Program Research Presentations

Able to tolerate a wide range of habitats, temperatures, and salinities, Carcinus maenas thrives in much of its non-native range, out-competing native crabs for resources while diminishing food supplies for a variety of marine and estuarine organisms. In Seadrift Lagoon, a manmade inlet of Bolinas Lagoon in Marin County, California, green crabs comprise a significant portion of benthic fauna, and trapping efforts began in 2009 to eradicate them. We analyzed several years of trapping data to monitor demographic changes for this closed population, performed larvae and megalopae sampling with pot scrubbers, and counted eggs on ovigerous females captured in Seadrift …

Performance Variation In Leptasterias Spp. Among Populations And Habitats, Caleb Shaw, Sarah Cohen

STAR Program Research Presentations

Leptasterias spp. are six rayed sea stars that are found in rocky intertidal habitats ranging from the California coast to Alaska. In central California, Leptasterias spp. can be found in a variety of intertidal habitats in mixed populations. There are multiple clades that represent these populations and it is thought that they may vary behaviorally, including habitat preference. To investigate this individuals were collected from Pigeon Point, San Mateo, CA and characterized into two habitat categories according to where they were found: rocky habitat and pool habitat. To test for behavioral variation among habitats, righting response was used as a …

Radiocarbon Isotopic Classification Of Deep Tropical Forest Soils, Brooke Butler, Karis J. Mcfarlane, Jennifer Pett-Ridge, Katherine A. Heckman

STAR Program Research Presentations

Tropical forest soils have an important role in global carbon (C) stocks. Small changes in the cycling of C could drastically affect atmospheric carbon dioxide (CO2) concentrations and active cycling of carbon in a forest community. Currently, little is understood of how tropical forest soils will respond to the increasing global temperatures. To examine the effects of warming/ drought on losses of older versus younger soil C pools, we implemented radiocarbon (14C) isotopic characterization of various soil plot samples and depths from the Luquillo Experimental Forest, Puerto Rico. 14C was measured using Accelerated Mass Spectrometry (AMS) from catalytically condensed carbon …

Winter Freeze Decreases The Emergence Of Fauna And Flora In California Vernal Pools, Korena S. Hendryx, Jamie Kneitel

STAR Program Research Presentations

Impacts of global climate change is observed in many ecological systems. Temporary aquatic ecosystems, including California vernal pools, are especially sensitive to climatic variation, but most species are adapted to the annual fluctuations in precipitation and temperature. Since vernal pools experience an inundation and desiccation every year, species that occupy the ecosystem have adaptations to this cycle. Many species survive drought by creating resting eggs to then re-emerge upon inundation However, climate changes outside the typical range may have deleterious effects on these populations. Moreover, climate variation can have secondary effects on the community. For example, the amount of precipitation …

An Investigation Of The Effect Of Malathion On Adaptive Plasticity Of Pseudacris Sierra, Michael Jonathan Maples

Master's Theses

This thesis is composed of two chapters. Chapter one reviews what is known about adaptive plasticity in response to predators, describes the physiological systems involved in such plasticity, and outlines the evolutionary consequences of adaptive plasticity. Chapter two describes a scientific experiment that investigates how malathion may impact adaptive plasticity in the Sierran Treefrog, Pseudacris sierra. Anuran tadpoles suffer high mortality rates due to predation. In response to strong selective forces relating to these high predation rates, tadpoles evolved the ability to adaptively respond to predators through morphological and behavioral plasticity. The morphological and behavioral responses are varied and depend …

The Pioneer Of Santa Rosa Island, Andrea Martinez, Michael Perez, Kathryn Mceachern, Sarah Chaney, Ken Niessen

STAR Program Research Presentations

Santa Rosa Island which is part of the Channel Islands in California has a ranching history that goes as far back as the year 1843. While rich in history, the island is no longer “rich” in native plant populations due to the sheep, cattle and other livestock that once occupied the island. As a result of these grazers that the ranchers livelihood depended on, a great disturbance in the native plant population took place. It is up to plants such as Baccharis pilularis, commonly known as Coyote brush, to assist these endangered and threatened plants to once again flourish …

Identification Of Saccharina Groenlandica (Phaeophyceae) Around The Svalbard Archipelago: Dna Barcoding Using Cytochrome C Oxidase Subunit 1 (Coi), Anniken Lydon

Master's Theses

In the Arctic, brown algae (kelps) and seaweeds are ecologically important: providing habitat, protection, and nutrients for invertebrate and vertebrate species living in nearshore environments. Migrations of biota between the North Pacific and North Atlantic Oceans have occurred periodically during Earth’s history leading to colonization of the Arctic Ocean. Around 3.5 Mya the “Great Trans-Arctic Biotic Interchange” occurred and the Laminariales order of kelp, thought to be of North Pacific origin, underwent a massive radiation and speciation event around the Arctic Ocean. Phylogenetic analysis performed on “Laminaria-like” specimens collected from six sampling locations around the Svalbard Archipelago identified …

Native Small Mammal Use Of An Invasive Grass: Heermann's Kangaroo Rats (Dipodomys Heermanni) And Veldt Grass (Ehrharta Calycina) In Coastal California, Juliana P. Trunzo

Master's Theses

Invasive species are generally regarded as detrimental to native communities because they cause increased competition and community structure alterations. There is therefore a critical need to understand the ecological processes underlying the establishment and spread of invasive species. While most studies to date have focused on the role of competition in species invasions, trophic dynamics may also play a fundamental role in the establishment and spread of non-natives, especially in cases when a non-native species experiences differential predation pressure relative to a native competitor. Herein I explore the potential for differential granivory pressure by a native rodent (Heermann’s kangaroo rat, …

Does The Production Of Isoprene Affect The Productivity Of Poplars?, Erik J. Mcfarland, Elizabeth Ann Parra, Greg Barron-Gafford, Rebecca Larkin Minor, Maggie Heard

STAR Program Research Presentations

Poplar trees are known to produce a chemical called isoprene that plays a complex, and not fully understood, role in the chemical process of photosynthesis. Understanding why plants produce isoprene and under what conditions will help scientists make more accurate predictions about poplars’ photosynthetic capabilities in future climates.

What benefit could isoprene provide a plant? The literature suggests its production could help plants tolerate heat stress. We studied two genetic lines of trees in a common garden of Populus, one line with the gene for producing isoprene and a second line without that gene. We subjected some trees of …

Are Circadian Cycles The Dominant Proteome Rhythym In The Intertidal Mussel Mytilus Californianus?, Kristina M. Koster, Cory Elowe, Lars Tomanek

STAR Program Research Presentations

Mytilus californianus, also known as the California mussel, is a marine bivalve that is abundant along the West coast from Alaska to southern Baja California. They mainly reside in the upper-middle intertidal zone and cling to pier pilings and surf exposed rocks. They create multi-layered beds, which form a habitat for algae and many species of invertebrates. Intertidal mussels live in a naturally dynamic environment. It has previously been reported (Connor and Gracey, 2011) that the 24-hour circadian (day to night) rhythm of the intertidal mussel Mytilus californianus is primarily responsible for its rhythmic gene expression, as opposed to …

Sea Turtle Hatchling Sex Ratios Determined Via Hormone Assay: Implications Of Climate Change?, William A. Hilton, Matthew Godfrey, Camryn D. Allen

STAR Program Research Presentations

Currently all species of sea turtles are listed as threatened or endangered with extinction under the U.S. Endangered Species Act. Due to their status, sea turtle conservation is a high priority for the U.S. National Marine Fisheries Service and U.S. Fish and Wildlife Service. One major challenge conservationists face is the lack of a noninvasive, cost efficient method for determining the sex of hatchling sea turtles. Because secondary sex characteristics (i.e. males have longer tails) are not evident until turtles start to reach sexual maturity, the sex of hatchlings is not easily determined. The least invasive way to determine the …

Spatial And Temporal Comparisons Of Gopher Rockfish (Sebastes Carnatus) Life History And Condition In South Central California, Natasha Leigh Meyers-Cherry

Master's Theses

Recent studies have shown environmental factors influence life history traits in fishes. Understanding intraspecific variability of life history characteristics and condition is necessary to determine local fisheries management strategies. Gopher rockfish, Sebastes carnatus, comprise 50% of the estimated shallow nearshore recreational rockfish catch in California, yet insufficient local data exist regarding life history traits and condition of this species. Our study locally defines growth parameters (maximum size and age), size (age) at reproductive maturity, and condition (hepatosomatic indices) for gopher rockfish in south central California. The growth parameter values of gopher rockfish from our study are similar to previously …

Estimating Migration Rates Between Populations Of Zostera Marina In The San Francisco Bay, Elizabeth S. Gutierrez

STAR Program Research Presentations

Eelgrass (Zostera marina) is a highly clonal marine angiosperm that can also reproduce sexually through flowering and seed formation. In a previous study, Fst values from six microsatellite loci suggested that a perennial San Francisco Bay subpopulation at Point Molate (Richmond, California) was able to recover from a drastic 2006 die-off through seed recruitment from neighboring eelgrass subpopulations, changing its reproductive strategy from clonal to sexual. Although Fst measures continue to be widely used in population genetics, the assumptions under which they operate are not always appropriate given certain circumstances, such small population sizes and/or asymmetrical migration rates. Our summer …

Jellyfish Throwdown: Invasive Versus Native, Brooke Bemowski, Trisha Huynh, Lindsay J. Sullivan, Wim Kimmerer

STAR Program Research Presentations

The San Francisco Bay Estuary is home to many species of marine and wildlife that create a delicate ecological balance. Invasive jellyfish introduced to the bay though cargo shipping are believed to be competing with the endangered delta smelt for the same food source of copepods. Samples of zooplankton were taken from high and low salinity zones in the San Francisco Bay over three years in months June through February to correlate with the peak of the jellyfish lifecycle. The preserved samples are looked through and jellyfish are removed and recorded. The species of jellyfish is determined using features such …