Ecology and Evolutionary Biology Commons^™

The Path To The Sea: Leatherback Hatchling Orientation At Sandy Point National Wildlife Refuge, Christina Macmillan, Kelly Stewart

STAR Program Research Presentations

Once sea turtle hatchlings emerge from their nest, they must find their way to the ocean by using cues such as a bright horizon and the slope of the beach. While moving toward the water, hatchlings often must navigate past predators and through vegetation, sticks, footprints in the sand, and other dangers such as ghost crab holes. Sometimes hatchlings become confused (or disoriented) and turn in circles to find the right route to the water. Sea turtle hatchlings also may become disoriented as a result of human impacts such as town lights or trash. The purpose of our experiment was …

Light Pollution Research Through Citizen Science, John Kanemoto

STAR Program Research Presentations

Light pollution (LP) can disrupt and/or degrade the health of all living things, as well as, their environments. The goal of my research at the NOAO was to check the accuracy of the citizen science LP reporting systems entitled: Globe at Night (GaN), Dark Sky Meter (DSM), and Loss of the Night (LoN). On the GaN webpage, the darkness of the night sky (DotNS) is reported by selecting a magnitude chart. Each magnitude chart has a different density/number of stars around a specific constellation. The greater number of stars implies a darker night sky. Within the DSM iPhone application, a …

Xrf Analyses Of Prehanford Orchards, Komal Rana

STAR Program Research Presentations

Subsequent to 1943, the use of Lead Arsenic was banned from the Orchards standing on the Hanford site. This use of Lead Arsenate pesticide was popular among the orchard owners and was dispersed over the site in a myriad of ways. The presence of the traces of lead and arsenic are found today, more than half a century later. Using a portable X-ray florescence analyzer (XRF), the values of lead and arsenic are evaluated while determining the efficiency of the equipment itself. Samples from different decision sites were collected, with lead arsenic values in the low, high and medium range …

Mother Convict Cichlids Inflict More Bites Upon An Intruder In Hot Temperatures, Jesse L. Heckendorf

STAR Program Research Presentations

Convict cichlids (Archocentrus nigrofasciatus) have developed to be extremely good parents by protecting their brood. Parental care leads to aggressive biting, chasing, and gill flaring to intimidate known predators. In this experiment, we show that environmental factors, such as the changing of temperature in this case, affect a female convict cichlid’s aggression toward caring for her offspring when an intruder is introduced. Females attack more in warmer water.

Salinity Distribution Of Microplankton In The San Francisco Estuary, Carrie Ann Sharitt, Lindsay Sullivan, Wim Kimmerer

STAR Program Research Presentations

Microplankton are a diverse group of planktonic organisms ranging from 0.02 to 0.2 millimeters. Since the group is defined solely by size, it spans numerous taxonomic groups, including both heterotrophs and autotrophs. Microplankton are abundant in all aquatic ecosystems and are important prey for many organisms, including bivalves, crustaceans, and fish. The San Francisco Bay is truly an estuary as saltwater enters the estuary under the Golden Gate Bridge and freshwater flows in from the Sacramento and San Joaquin Rivers. Thus, there is a gradient of salinity from freshwater (0) in the rivers to saltwater by the Golden Gate Bridge …

Behavioral And Hormonal Flexibility Across Light Environments In Guppies (Poecilia Reticulata), Julia C. Walz

Master's Theses

Behavior may be dramatically influenced by changing environments, and differences in light intensity environments may have important behavioral consequences. One approach to understanding changes in behavior is by studying behavioral syndromes, suites of correlated behaviors reflecting between individual consistencies in behavior expressed within a behavioral situation (e.g., correlations between antipredator behaviors in different habitats), or across behavioral contexts (e.g., correlations among feeding, antipredator, or mating behavior) (Sih et al. 2004a). Guppies (Poecilia reticulata) provide a great model system to study behavior. Guppies are small, freshwater tropical fish that inhabit still pools in swift-flowing streams, and the backwaters of small rivers …

Examining The Impacts Of State Route 101 On Wildlife Using Road Kill Surveys And Remote Cameras, Sara Ann Snyder

Master's Theses

Roads can negatively impact the survival of wildlife populations through additional mortality from road kill and population fragmentation caused by road avoidance behaviors. The 11.9 mile section of State Route 101 between the towns of San Luis Obispo and Atascadero, CA, USA, cross a mountain lion movement corridor and an area important to maintaining ecological connectivity between protected lands in the Los Padres National Forest to the north and south.

I examined the spatial patterns and landscape and roadway factors associated with road kill occurrence for six taxa; large mammals, mesocarnivores, squirrels, rabbits, birds and raptors. Between 1 May 2009 …

Investigating Meter Scale Topographic Variation As A Factor Of Monterey Pine (Pinus Radiata) Growing Conditions At Kenneth Norris Rancho Marino Reserve, Cambria, Ca, William J. Meyst

Natural Resources Management and Environmental Sciences

Endemic Monterey pine (Pinus radiata) is limited to three locations in California due to its unique ecological requirements. This project was conducted to investigate spatial growth patterns ofMonterey pine over complex ground surfaces. The coastal hills of Rancho Marino Reserve, Cambria, were surveyed using four 150-m transects to quantify and record ground surface features and growing conditions ofMonterey pine. Changes in elevation of each transect were measured using an Abney level. Linear ground surfaces were found at 86% (344 of 400) of survey nodes. Convex ground surfaces were found at 10.5% of survey nodes (42 of 400). Of …

Photosynthetic Thermal Tolerance And Recovery To Short Duration Temperature Stress In Desert And Montane Plants: A Comparative Study, David William Gallagher

Master's Theses

• Climate change models predict an increase in frequency and amplitude of extreme weather events, including heat waves. To better predict how the composition and distribution of plant assemblages might respond to these changes in temperature, it is important to understand how species currently respond to these extremes. Photosynthetic thermal tolerance (T₂₅)and photosynthetic recovery (RT₂₅) were quantified in 27 species. We also studied the relationships between T₂₅, RT₂₅ and leaf mass per area (LMA). Leaf temperature was also monitored in the field.
• Leaves used in this study were collected from two distinct …

Monarch Butterfly (Danaus Plexippus) Tree Preference And Intersite Movement At California Overwintering Sites, Jessica Lynn Griffiths

Master's Theses

Managing Monarch butterfly overwintering groves: making room among the eucalyptus

Proper management and conservation of the coastal California overwintering sites used by western Monarch butterflies (Danaus plexippus L.) is critical for continued use of these sites by monarchs. Many management efforts are currently concentrating on eucalyptus-only sites because of the prevailing notion that monarchs prefer eucalyptus over native tree species. Yet, whether a preference exists or not has never been tested. Herein, we test the “eucalyptus preference” hypothesis with data from five overwintering sites comprised of blue gum eucalyptus (Eucalyptus globulus) and at least one other native tree …

The Ecological Effects Of Cattle Grazing On Reptiles And Small Mammals In A San Joaquin Valley Grassland, Michael William Tom

Master's Theses

Livestock grazing is a common and extensive land use practice in the United States occurring in a wide range of habitat types. As such, livestock grazing has the potential to alter ecosystem structure, function and community composition. The primary component (Chapter 1) of this thesis examined the effects of cattle grazing in a San Joaquin Valley grassland on two target taxa: reptiles and small mammals. The study took place on the Chimineas Unit of the Carrizo Ecological Reserve, San Luis Obispo County, California during Fall 2009 and Spring 2010. These taxa were sampled on matched pairs of two grazed and …

Census And Mapping Of Chorro Creek Bog Thistle In Reservoir Canyon, San Luis Obispo, Ca, Tyler Michael Lutz

Biological Sciences

Chorro Creek bog thistle (Cirsium fontinale var. obispoense) is a federally endangered variety of Fountain thistle endemic to western San Luis Obispo County. The U.S. Fish and Wildlife Service knows of nineteen populations, many with multiple colonies. A population was discovered in the Reservoir Canyon Natural Reserve in 2001, but has not been monitored or described since the time of its discovery. In fall of 2013, a census of the population was performed, the four colonies were mapped, and a floristic survey was conducted. A field experiment was initiated to determine if reducing the riparian canopy coverage can …

An Assessment Of Habitat Suitability For Pronghorn Populations Of The Central Valley Region Of California, Virginia Burroughs

Master's Theses

Efforts to reintroduce and maintain populations of pronghorn (Antilocapra americana) to the California Central Valley, specifically the Carrizo Plain National Monument (CPNM) and the Mojave Desert (Antelope Valley) portion of Tejon Ranch, have largely been unsuccessful due to dwindling numbers of translocated animals. The objective of this study was to improve upon previous models for the CPNM using aerial survey data and then apply the model to the Tejon Ranch. Aerial survey data collected from 2000-2010 on the CPNM was used to establish “use” and “non-use” areas in the model. Model variables included vegetation type (forest, shrub, grassland, …

Zooplankton Trophic Ecology In The San Francisco Estuary During Summer As Determined By Stable Isotope Analysis, Kyla Bradylong, Steven Westbrook, Julien Moderan, Wim Kimmerer

STAR Program Research Presentations

Declines in the abundance of several pelagic fish species in the upper San Francisco Estuary have prompted investigation into food web interactions within the estuary and delta (the lower Sacramento and San Joaquin Rivers). This area is characterized by low primary production and pelagic food webs much longer and reticulated than previously thought, implying low efficiency in the energy transfers from primary producers to planktivorous fish. We determined the carbon and nitrogen stable isotope (SI) composition of zooplankton samples collected monthly between June 2012 and February 2013 at eight stations along the salinity gradient. As consumers SI composition reflects that …

Big Babies, Big Mammas?: Relationship Of Leatherback Hatchling Size And Mother Size, Shane Morales, Violet Campbell, Kelly Stewart

STAR Program Research Presentations

Individual leatherback hatchlings vary in size when compared to individuals from other nests, as well as individuals from the same nest. It is thought that many factors affect hatchling size but that one of the most influential factors is maternal size. Of all the aspects of a mother which could affect hatchling size, evidence for question concerning influence of mother size is determinable within the field using minimal tools and basic statistical analysis. If a direct correlation exists between mother size and hatchling size then the claim can be made that larger mothers produce larger offspring while smaller mothers produce …

Abundance And Distribution Of Microplankton In The San Francisco Estuary, Carrie Ann Sharitt, Lindsay Sullivan, Wim Kimmerer

STAR Program Research Presentations

Microplankton are a diverse group of planktonic organisms ranging from 0.02 to 0.2 millimeters. Since the group is defined solely by size, it spans numerous taxonomic groups, including both heterotrophs and autotrophs. Microplankton are abundant in all aquatic ecosystems and are important prey for many organism, including bivalves, crustaceans, and fish. Little is known about the microplankton community in the San Francisco Estuary, and information on their abundance and distribution will help scientists better understand their role in local foodwebs. This research quantified the abundance and distribution of microplankton in the San Francisco Estuary from 2010 to 2012. Microplankton were …

Jellyfish Identification And Quantification In The San Francisco Estuary, Amalia Borson, Lindsay L. Sullivan, Wim Kimmerer

STAR Program Research Presentations

As potential predators and competitors of plankton-eating fish, jellyfish have the potential to negatively impact fish populations. Jellyfish were collected weekly with plankton tows from the RombergTiburonCenterpier in Tiburon, CA. Since some jellyfish were too small to identify, one tow was collected and preserved to record abundances, and a second tow was collected to rear jellyfish until distinguishing characteristics were visible enough for identification. Jellyfish in the preserved tows were then identified, measured, and counted, and their abundance (number m^-3) was calculated. Jellyfish from the second tows were reared in plastic buckets that were lightly bubbled using aquarium …

Temporal Variation In Larval Release In Botrylloides Violaceous, Damion J. Delton, Sarah Cohen

STAR Program Research Presentations

Despite Botrylloides violaceous being a globally invasive species in temperate marine habitats, little is known about it’s natural dispersal behavior. Previous work (Delton et al, 2011) suggests behavioral inferences based on a related and much more commonly studied species may not be appropriate, potentially due to a large size difference between the non-feeding larvae of these two species. Here, we consider factors that may affect dispersal potential. To study how light affects larval release, we measured timing of larval release in the field and compared larval size and time of release. Colonies were collected from floating docks in Richmond, CA …

Feeding Ecology Of Delta Smelt During A Seasonal Pulse Of Turbidity, William A. Hilton, Aaron Johnson, Wim Kimmerer

STAR Program Research Presentations

The delta smelt (Hypomesus transpacificus) is a small, pelagic fish endemic to the San Francisco Estuary (SFE) and protected under federal and state endangered species acts. This study examines the diet of adult delta smelt during their spawning migration in the winters of 2010 and 2012. Delta smelt and their zooplankton prey were sampled concurrently during a seasonal pulse of turbidity at sites along their migratory route from the low salinity zone in Suisun Bay to the fresher waters of the Sacramento/San Joaquin Delta. Gut contents were identified to the lowest possible taxon and counted, along with zooplankton …

A Multispecies Avian Abundance Analysis In Riparian And Oak Woodland Habitats On The California Central Coast, Jacy Hyde

Biological Sciences

I investigated the abundance and diversity of riparian and oak woodland birds in a section of the Los Padres National Forest in Coastal Central California. Point counts were conducted in Oak Woodland and Riparian habitats during the summer of 2012. Point counts were replicated in time (2x) and space (25 replicates). The data were analyzed using Program Distance to correct for differing detection probabilities between species and habitat types. The two habitat types showed no significant difference in species richness. For most species, there was no difference in density between riparian and oak woodland habitats. However, the two species with …

A Comparison Of Relative Ear Length Between Two Neighboring Populations Of Peromyscus Maniculatus, Joshua S. Willems

Biological Sciences

This study attempts to determine if a significant difference in relative ear length exists between two neighboring populations of Peromyscus maniculatus on the central coast of California. Data was collected from individuals trapped at two plots in the Guadalupe-Nipomo Dunes National Wildlife Refuge and two plots near Black Lake, under the supervision of Francis X. Villablanca, Ph. D. of California Polytechnic State University, San Luis Obispo. A total of 98 individuals were captured over the course of three nights of trapping. A regression analysis was performed comparing the ear lengths of each population relative to body size. The analysis of …

Using Stable Isotope Analysis Of Zooplankton To Document Trophic And Biogeochemical Changes In The San Francisco Estuary, Steven C. Westbrook, Julien Moderan

STAR Program Research Presentations

Zooplankton represent a vital link between phytoplankton and fish, like the endangered Delta Smelt. Human interferences (nitrates from waste water, flow alteration, invasive species introduction…) have altered the structure of the San Francisco Estuary (SFE) ecosystem. We use stable isotope analysis to improve our knowledge of the planktonic food web in the SFE and gain insights into its evolution over the past decades. We use the ratios of certain isotopes (Nitrogen, Carbon, Sulfur, etc.) in different species of zooplankton to tell us what it is feeding on as well as the trophic level it feeds in. My research focused on …

An Analysis Of Human Disturbance To Rocky Intertidal Communities Of San Luis Obispo County, Grant Tyler Waltz

Master's Theses

ABSTRACT

An Analysis Of Human Disturbance To Rocky Intertidal Communities Of San Luis Obispo County

Grant Tyler Waltz

The number of coastal areas open to public access in California and San Luis Obispo County is increasing due to the acquisition by California State Parks of land previously owned by private entities. For example, California State Parks acquired property from the Hearst Corporation in 2005, which included 18 miles of coastline. California State Parks is responsible for providing public access in these newly acquired areas and also for maintaining the health of the natural systems found on these properties. Part of …

A Genetic Survey Of English Sole Populations In The Salish Sea, Elizabeth S. Gutierrez, Gary A. Winans, Jon Baker, Amanda Cope

STAR Program Research Presentations

This summer I interned at the Northwest Fisheries Science Center in Seattle, WA and participated in NOAA’s Salish Sea Project. The Salish Sea Project’s goal is to identify genetically distinctive groups of species in the Salish Sea that may have unique evolutionary and/or adaptive backgrounds. These findings will allow NOAA to promote and monitor the natural production of species in the Salish Sea, to select representative populations for experimental work regarding pollution, ocean acidification and climate change, to contribute to managing the ecosystem for intra- and inter-species diversity, and to help make informed decisions about adaptive management and marine protected …

Functional Response Of Protected Larval Stage Delta Smelt (Hypomesus Transpacificus), Jorge Ruiz, Lindsay Sullivan, Wim Kimmerer, Joan Lindberg

STAR Program Research Presentations

Delta smelt (Hypomesus transpacificus) is a protected slender-bodied fish endemic to the San Francisco Estuary. Smelt prey upon various zooplankton including the copepods such as Pseudodiaptomus forbesi. This experiment studied the prey maximum feeding rate of 2 larval stages (21 DHP, 35 DPH) of Delta smelt on various concentrations of P. forbesi. The copepod prey was offered at 7 different concentrations (2No./L–120No./L). After feeding was terminated the free prey and ingested prey were counted and analyzed to find the feeding rate of Delta smelt. Maximum feeding rate was found to be at much higher prey densities …

Developing Monitoring Methods For Leptasterias Spp. As Sentinel Species In Detecting Local Environmental Changes, Zachary Sturbaum, Kathryn Nuessly, Riley J. Smith, C. Sarah Cohen

STAR Program Research Presentations

Leptasterias spp., a six-rayed sea star, is found in rocky intertidal habitats ranging from Alaska to central California. Leptasterias spp. can be monitored on a broad scale throughout their range by a variety of means using timed counts and random plot censusing in order to detect both large-scale and local-level changes in the environment due to climate change, land-based human activity, or other environmental events. Leptasterias brood their young externally until the embryos grow into fully developed juveniles. These juveniles disperse by crawling away, limiting their dispersal potential. This localized dispersal provides an opportunity to use Leptasterias spp …

Testing The Salinity Tolerance Levels Of Similar Invasive Species Found In The San Francisco Bay, Julia M. Smith, C. Sarah Cohen, Elizabeth Sheets

STAR Program Research Presentations

Testing the salinity tolerance levels of similar invasive species found in the San Francisco Bay

Julia Smith^1,2, Elizabeth Sheets², and C. Sarah Cohen²

¹Department of Teacher Education, California State University, Sacramento ²Department of Biology and Romberg Tiburon Center, San Francisco State University

Three non-indigenous colonial ascidian species, Botrylloides violaceus, Botrylloides diegensis, and Botryllus schlosseri, have become well established in San Francisco Bay. Two species, B. violaceous and B. schlosseri, are globally distributed, and understanding the salinity ranges and tolerances of these successful invaders in their introduced habitats is important for …

Size And Weight Changes Of Leatherback Hatchlings Among Emergence Groups, Shane Morales, Kelly Stewart

STAR Program Research Presentations

In ideal leatherback sea turtle nests, all the hatchlings move together as a single group through the sand to leave the nest. Often, though, hatchlings emerge in two separate groups hours or days apart while others remain stuck in the sand where they may die unless they are dug out (excavation). First emergence groups spend the shortest amount of time in the sand while excavated hatchlings spend the longest amount of time in the sand (typically three days longer than first emergence hatchlings). Individuals from each of the separate emergences were weighed and measured (carapace only) in order to compare …

Mapping Plant Biodiversity Hotspots At The County Scale: A New Tool For Establishing Resource Conservation Strategies, Kristie Haydu

Master's Theses

Myers first identified the world’s 25 biodiversity hotspots and pioneered innovative ideas about the usefulness of biodiversity models for establishing long-term resource conservation strategies at global scales. Since Myers, most of the subsequent studies using hotspot science for biodiversity modeling have used large spatial scales like countries, provinces or states, and other biogeoraphic regions. The California Floristic Province continues to be one of the recognized global biodiversity hotspots. Our study site, San Luis Obispo County is within this hotspot and we created a map of plant biodiversity hotspots at the county scale using GIS technology. We wanted to determine the …

Seasonal Food Habits Of Burrowing Owls (Athene Cunicularia) In Human-Altered Landscapes, Carie Marie Wingert

Master's Theses

In 2004, I initiated a year-long study to investigate the food habits of burrowing owls (Athene cunicularia). Burrowing owls have been found in a variety of human-altered landscapes; however, little is known about burrowing owl food habits in urban landscapes. Burrowing owl food habits during the non-breeding season are also largely undocumented, despite increasing concern over the survival of overwintering burrowing owls. Differences in prey consumption between reproductive and non-reproductive owls during the breeding season have not yet been examined. I collected pellets over a 12 month period at four study sites affected by different levels of human …