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Management Recommendations For Ecological Restoration On The Little River Parcel, Maya Sady Partain, Garitt Mathews Jan 2019

Management Recommendations For Ecological Restoration On The Little River Parcel, Maya Sady Partain, Garitt Mathews

Environmental Science & Management Senior Capstones

Ecological restoration is an important aspect of land management. Data collection and ongoing monitoring help inform restoration decisions and determine their effectiveness. In this project, we followed a monitoring protocol provided by the Trinidad Coastal Land Trust to assess the 2019 status of their Little River parcel, a fifteen-acre area near the mouth of Little River in Trinidad, California. We performed a site analysis of invasive plant species and recorded their extent and location, as well as noting other observations of the ecology, topography, and biology of the site. After making our observations, we recommended land management methods woven together …


The Effect Of Manipulating Vertical Motion On Running Economy, Claire Copriviza Jan 2019

The Effect Of Manipulating Vertical Motion On Running Economy, Claire Copriviza

Cal Poly Humboldt theses and projects

While several biomechanical factors have been identified as key determinants of running economy (i.e. metabolic cost), the influence of individual mechanical factors such as center of mass vertical motion (ΔCoMz) remains unclear. The purpose of this study was to determine how manipulating ΔCoMz effects running economy. Twelve runners used a visual biofeedback system to control their ΔCoMz during running as we measured the metabolic, kinematic, and muscle activation responses to the different levels of ΔCoMz. Running economy was strongly correlated to ΔCoMz and was optimized at an intermediate center of mass vertical motion …


Distribution Of Sea Star Wasting Disease Symptoms In Pisaster Ochraceus In The Rocky Intertidal Zone, Jana N. Litt Jan 2019

Distribution Of Sea Star Wasting Disease Symptoms In Pisaster Ochraceus In The Rocky Intertidal Zone, Jana N. Litt

Cal Poly Humboldt theses and projects

Beginning in 2013, many species of sea stars (phylum Echinodermata) along the Pacific coast experienced severe mortality due to sea star wasting disease (SSWD). The ochre sea star, Pisaster ochraceus, experienced one of the highest mortality rates during this outbreak. To test the hypothesis that the intertidal distribution of ochre sea stars influences the incidence and progression of SSWD symptoms, I documented the occurrence of symptoms and survivorship in adult and juvenile stars in the upper and lower portions of the mid-intertidal zone. I also chronicled the progression of SSWD symptoms among individually tagged adult stars to assess changes in …


Targeting Social Cohesion In Female Roosevelt Elk (Cervus Canadensis Roosevelti) Groups Minimizes Survey Efforts For Fecal Dna Capture-Recapture Estimates Of Abundance, Rudolph Gabriel Mena Jan 2019

Targeting Social Cohesion In Female Roosevelt Elk (Cervus Canadensis Roosevelti) Groups Minimizes Survey Efforts For Fecal Dna Capture-Recapture Estimates Of Abundance, Rudolph Gabriel Mena

Cal Poly Humboldt theses and projects

Group size abundance estimates of Roosevelt elk (Cervus canadensis roosevelti) in Humboldt and Del Norte counties, California have largely been inferred through visual counts. However immigration and emigration, the inability to sight elk behind viewing obstructions, and a lack of individual identifiers makes precise and accurate estimates difficult to obtain. Using DNA collected through fecal samples left by elk groups can aid in addressing these difficulties. I tested the hypothesis that GPS (Global Positioning System) collar data from adult female elk could indicate discrete site use locations of their social groups, which in turn yield sufficient sample sizes …


The Effect Of Interval Intensity On Time To Exhaustion During High Intensity Interval Training (Hiit) Running In Recreational Male Runners, Andrew M. Hahn Jan 2019

The Effect Of Interval Intensity On Time To Exhaustion During High Intensity Interval Training (Hiit) Running In Recreational Male Runners, Andrew M. Hahn

Cal Poly Humboldt theses and projects

High Intensity Interval Training (HIIT) has become extremely popular in recent years, however, current HIIT prescriptions lack guidelines regarding interval intensities and associated margins. The purpose of this study is to investigate Run Time to Exhaustion (Te) and provide insight regarding HIIT intensities for future aerobic exercise programming. Ten healthy adult male recreational runners (Age=22.9 ± 2.5 yr., Ht=1.72 ± 0.1m, BM=74.1 ± 7.4 kg) measured maximal oxygen consumption (VO2max) (52.4 ± 6.1ml/kg/min) with a graded exercise test (GXT). Running speed was determined using ACSM running equation for exercise metabolism. Protocols 1-3 were HIIT running sessions, and Protocol 4 was …


Evaluation Of Range-Wide Occupancy And Survey Methods For The Giant Kangaroo Rat (Dipodomys Ingens), Alyssa E. Semerdjian Jan 2019

Evaluation Of Range-Wide Occupancy And Survey Methods For The Giant Kangaroo Rat (Dipodomys Ingens), Alyssa E. Semerdjian

Cal Poly Humboldt theses and projects

Though habitat suitability and occupancy are often correlated, they cannot always be inferred from each other. Therefore, a solid understanding of both is essential to effectively manage species. Recent studies have assessed range-wide habitat suitability for the giant kangaroo rat (Dipodomys ingens; GKR), but data regarding occupancy is lacking in parts of its distribution. Satellite and aerial imagery were used to identify GKR burrows across their known range, producing a range-wide occupancy map and non-invasive survey methods including track plates, manned flight, unmanned aerial vehicle, and sign surveys were conducted to determine effective methods for monitoring GKR occupancy. …


Analysis Of Aboral Spine Variation In The Forcipulate Sea Star, Pisaster Ochraceus (Brandt 1835), Angela Jordane Jones Jan 2019

Analysis Of Aboral Spine Variation In The Forcipulate Sea Star, Pisaster Ochraceus (Brandt 1835), Angela Jordane Jones

Cal Poly Humboldt theses and projects

Rocky intertidal zones are highly dynamic environments that exhibit substantial spatial and temporal variation in abiotic conditions, which can drive body form variation and energy allocation within calcifying species. Wave exposure, specifically, has been shown to be a significant driver of skeletal and structural morphology in organisms including gastropods, bivalves, and sponges. Many of such organisms, from sponges to echinoderms, rely on calcium carbonate for structural support and protection.

In the phylum Echinodermata (named for possessing a ‘spiny skin’), research on the form and function of calcium carbonate spines is largely relegated to Class Echinodea (e.g., urchins and sand dollars) …


Competition, Climate, And Drought Effects On Tree Growth In An Encroached Oak Woodland In Northern California, Jill J. Beckmann Jan 2019

Competition, Climate, And Drought Effects On Tree Growth In An Encroached Oak Woodland In Northern California, Jill J. Beckmann

Cal Poly Humboldt theses and projects

Oregon white oak (Quercus garryana Douglas ex Hook.) is experiencing increasing competition from Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) across its range at the same time as climate models are predicting increasing climate variability, including drought. Management recommendations that consider competition dynamics between these species under a changing climate are therefore needed for oak woodlands, but we do not currently understand the combined effects of competition, climate, and drought in this ecosystem. This research examines radial tree growth and drought response in Oregon white oak and Douglas fir in an encroached oak woodland near Kneeland, California. Stem maps …


Freshwater And Marine Survival Of Coho Salmon (Oncorhynchus Kisutch) As A Function Of Juvenile Life History, Grace Katherine Ghrist Jan 2019

Freshwater And Marine Survival Of Coho Salmon (Oncorhynchus Kisutch) As A Function Of Juvenile Life History, Grace Katherine Ghrist

Cal Poly Humboldt theses and projects

Juvenile Coho Salmon (Oncorhynchus kisutch) in coastal California streams exhibit various life history strategies during their freshwater development. One strategy of interest to managers and conservationists is the early migrant. Juvenile early migrants emigrate from natal habitat into lower parts of the watershed or estuary during their first fall or winter, where they rear before migration to the ocean. By contrast, the more prevalent spring migrant resides in natal reaches over the winter and migrates directly to the ocean the following spring. Salmon monitoring programs generally estimate juvenile production and demographic rates using only spring migrants, and these …


Multidecadal Change In Aspen Experiencing Long-Unburned, Mixed-Severity Wildfire, And Reburn Disturbance Regimes, Cerena Brewen Jan 2019

Multidecadal Change In Aspen Experiencing Long-Unburned, Mixed-Severity Wildfire, And Reburn Disturbance Regimes, Cerena Brewen

Cal Poly Humboldt theses and projects

Quaking aspen (Populus tremuloides) is a valued, minor component on western landscapes. It provides a wide range of ecosystem services, and has been in decline for the last century. This decline may be explained partially by the lack of fire on the landscape as aspen benefit from fire that eliminates conifer competition and stimulates reproduction through root suckering. Managers are interested in aspen restoration but have a lack of knowledge about their spatial dynamics in response to fire. Improving our understanding of aspen stand spatial changes over time may be important for maintaining their presence on landscapes where …


Host-Plant Specialization And Nesting Biology Of Anthidium Placitum (Megachilidae) In Northwest California, Christopher Pow Jan 2019

Host-Plant Specialization And Nesting Biology Of Anthidium Placitum (Megachilidae) In Northwest California, Christopher Pow

Cal Poly Humboldt theses and projects

Premise of the study: Although the study of bees and their pollination services has grown immensely in recent years, the natural history of most solitary bee species is still largely unknown. The goal of this study was to contribute to the natural history dossier of a late-season wool carder bee, Anthidium placitum Cresson (Megachilidae), by establishing which plants it uses as sources of nectar and pollen as well as documenting details of its flower-handling behavior, mating behavior, and nesting biology in northwestern California.

• Methods: Field observations were made at five sites in Del Norte, Humboldt, Siskiyou, and Trinity counties. …


Long-Term Effectiveness Of Fuel Treatments In Oak And Chaparral Stands Of Northern California, Caroline Ann Martorano Jan 2019

Long-Term Effectiveness Of Fuel Treatments In Oak And Chaparral Stands Of Northern California, Caroline Ann Martorano

Cal Poly Humboldt theses and projects

Fuel reduction treatments are broadly implemented to reduce the risk of extreme wildfire. Yet, research on the long-term effectiveness and ecological consequences among these treatments is lacking. In this study, I examined short- and long-term changes in fuels and understory vegetation after treatment in chaparral and oak-dominated stands of Whiskeytown National Recreation Area. Treatments included mastication and spring burning, spring burning only, mastication only, and hand-thinning. Treatments were applied randomly to 1 to 2 units within each of 10 blocks. Two plots were established in each treatment unit and fuel and vegetation data was collected and analyzed at the block …


Effects Of Longline Oyster Aquaculture On Benthic Invertebrate Communities In Humboldt Bay, California, Hannah C. Coe Jan 2019

Effects Of Longline Oyster Aquaculture On Benthic Invertebrate Communities In Humboldt Bay, California, Hannah C. Coe

Cal Poly Humboldt theses and projects

Oyster aquaculture has had a commercial presence in Humboldt Bay for nearly 60 years and has experienced changes in scope and methodology as the industry has grown. The traditional method of bottom-culture oyster beds has been phased out, with longline oyster aquaculture becoming the common replacement. However, this transition has preceded much of the research regarding potential impacts to the broader ecosystem. The benthic invertebrate community of Humboldt Bay is a vital food source for many commercially important fishes, as well as for the many shorebirds that utilize Humboldt Bay. The importance of the invertebrate community to the ecosystem highlights …


The Effect Of Yoga On The Total Number Of Off-Task Behaviors For Children With Autism Spectrum Disorder, Ashley N. Jovick Jan 2019

The Effect Of Yoga On The Total Number Of Off-Task Behaviors For Children With Autism Spectrum Disorder, Ashley N. Jovick

Cal Poly Humboldt theses and projects

BACKGROUND: Autism spectrum disorder (ASD) is a complex developmental disability. Signs will usually appear during early childhood and affect a person’s ability to communicate and interact with others. ASD is defined by a certain set of behaviors and is a ‘spectrum condition’ that affects individuals differently and to varying degrees. Two major behaviors associated with ASD are poor motor skills and sensory activities.

PURPOSE: The purpose of this investigation is to examine the effectiveness of yoga on reducing off-task behaviors in children with Autism Spectrum Disorder.

METHODS: Off-task behavior data will be taken in Baseline and Intervention Phases. Video analysis …


Exercise And The Effects Of Off-Task Time Behavior During Academic Time Among Children With Disabilities, Morgan L. Wood Jan 2019

Exercise And The Effects Of Off-Task Time Behavior During Academic Time Among Children With Disabilities, Morgan L. Wood

Cal Poly Humboldt theses and projects

BACKGROUND: Physical activity participation has decreased, especially for the special education community. With no time for exercise, or the proper exercise, on task time for children with intellectual disabilities can be a very challenging time.

PURPOSE: The purpose of this study was to examine the impact of a physical activity program (i.e., yoga) on the total number of off-task behaviors and total time on-task for children with I.D. during their academic period.

METHODS: On task time data will be collected during control and experimental sessions. Statistical analysis will be conducted to determine if exercise before instructional time effects on task …


Childhood And Trauma: The Effects Of Adverse Childhood Experiences On The Brain, Behavior, And Learning In The Elementary School Classroom, Aeryn Aguilar Jan 2019

Childhood And Trauma: The Effects Of Adverse Childhood Experiences On The Brain, Behavior, And Learning In The Elementary School Classroom, Aeryn Aguilar

Cal Poly Humboldt theses and projects

A variety of studies have been conducted on how trauma, caused by emotional, physical, or verbal abuse, impact children’s lives. Many of the studies which involved observations and assessments were done with the preexisting knowledge that these children had been through a traumatic experience. Instead of looking at behavior of known cases, this study’s goal is to find out whether or not children’s observable behaviors can predict cases of trauma. For example, is acting out or defiance a key sign of trauma or is it part of the typical development for the elementary school-age group? This thesis takes into account …


The Effects Of Circuit Training On Decreasing Off-Task Behaviors For Children With Autism Spectrum Disorder, Juan C. Hernandez Jan 2019

The Effects Of Circuit Training On Decreasing Off-Task Behaviors For Children With Autism Spectrum Disorder, Juan C. Hernandez

Cal Poly Humboldt theses and projects

Autism spectrum disorder (ASD) is the fastest growing developmental disability according to Centers for Disease Control and Prevention (CDC). Prevalence shows that 1 in 59 children are born with Autism Spectrum Disorder, and having this population engage in physical activity will reduce off-task behavior. The purpose of this study is to determine the benefits of circuit training on decreasing off-task behavior while improving health for children with Autism Spectrum Disorder, and encourage parents, teachers, and specialist to incorporate similar drills, activities, and exercises with the ASD population. In this study, a special education high school teacher and APE instructor will …


Effects Of A Race Timer On The Three Minute All-Out Test For Critical Power, Paul K. Mandell Jan 2019

Effects Of A Race Timer On The Three Minute All-Out Test For Critical Power, Paul K. Mandell

Cal Poly Humboldt theses and projects

Maximal exercise testing is commonly employed by exercise scientists in order to assess an athlete's’ capabilities and inform future training goals and tactics. The Critical Power (CP) concept provides a novel perspective on the physiological capacity of an individual to perform work. The 3 Minute All-Out Test (3MT) for critical power was developed by Vanhatalo, Doust, & Burnley in 2006. Concerns about pacing during the test lead to the development of protocol which blinds participants to time during the test. Twelve healthy active males were recruited to participate in the current study on the effects of a race timer on …


The Effects Of Concussion On Tandem Gait Performance With Secondary Cognitive Tasks, Angel Lomeli Jan 2019

The Effects Of Concussion On Tandem Gait Performance With Secondary Cognitive Tasks, Angel Lomeli

Cal Poly Humboldt theses and projects

Identifying concussions occurs with a battery of cognitive and motor tests. However, these tests are performed independently as primary tasks. Research has demonstrated amplified motor differences due to concussion when performing simultaneous cognitive tasks (i.e. dual-tasks). The Tandem Gait Test (TGT) is used in concussion assessment and has only moderate sensitivity and specificity alone. The aim of this study was to determine the effect of concussion on TGT performance with secondary cognitive tasks. Six concussed participants (age 22.6 ± 2.8) and fourteen healthy participants (age 23.8 ± 2.7) were recruited through the North Coast Concussion Program within 13 days (7 …


Ecological Consequences Of Sea Star Wasting Disease: Non-Consumptive Effects And Trait-Mediated Indirect Interactions From Pisaster Ochraceus, Timothy Ian Mcclure Jan 2019

Ecological Consequences Of Sea Star Wasting Disease: Non-Consumptive Effects And Trait-Mediated Indirect Interactions From Pisaster Ochraceus, Timothy Ian Mcclure

Cal Poly Humboldt theses and projects

Consumptive effects (CEs) of predators are an important factor in structuring biological communities, but further work is needed to understand how the interaction between spatial and temporal differences in predator density affects non-consumptive effects (NCEs) on prey. NCEs can cause indirect effects on food resources, known as trait-mediated indirect interactions (TMIIs), and thus can also affect community structure. However, few studies have considered the relationships between spatial and temporal predator density variation and the strength of NCEs and TMIIs in the natural environment. The ochre star Pisaster ochraceus is common predator of the herbivorous black turban snail Tegula funebralis, imposing …


Converting Coast Redwood/Douglas-Fir Forests To Multiaged Management: Residual Stand Damage, Tree Growth, And Regeneration, Robert Thomas Muma Jan 2019

Converting Coast Redwood/Douglas-Fir Forests To Multiaged Management: Residual Stand Damage, Tree Growth, And Regeneration, Robert Thomas Muma

Cal Poly Humboldt theses and projects

There is increased interest in multiaged management as a silvicultural and restoration tool in redwood forests of California. The effect of varying residual densities and spatial arrangements on residual stand damage, tree growth and regeneration was studied in a multicohort silviculture experiment on Jackson Demonstration State Forest. Four treatments varying in residual stand density or spatial arrangement were replicated at four sites. The experiment provided 4-year periodic growth measurements of residual trees and annual measurements of redwood and tanoak sprout height increments. Residual trees were more likely to sustain bole scarring when retained at higher densities. Crown damage was more …


Application Of The Predicted Repetitions-To-Failure Perceived Exertion Scale For The Nfl-225lb Bench Press Test, Anthony G. Ratto Jan 2019

Application Of The Predicted Repetitions-To-Failure Perceived Exertion Scale For The Nfl-225lb Bench Press Test, Anthony G. Ratto

Cal Poly Humboldt theses and projects

PURPOSE: To assess how accurately Division II NCAA football players can predict repetitions-to-failure (RTF) during the bench press exercise using an absolute load of 225-lbs by comparing predicted repetitions-to-failure with actual repetitions-to-failure. METHODS: Twenty football players (age 20 ± 2 years; height 1.85 ± .06 m; weight 110.1 ± 19.3 kg) without muscular or skeletal injuries were tested for their 1repetition maximum (1-RM) in the bench press, and then performed 1 set to concentric failure with 225-lbs. Subjects predicted how many repetitions they could perform after the warm-up and again after the fourth, eighth, twelfth repetitions. A general regression analysis …


Tree Squirrels And Fishers In Northern California: The Effects Of Masting Hardwoods On Stand Use, Andria M. Townsend Jan 2019

Tree Squirrels And Fishers In Northern California: The Effects Of Masting Hardwoods On Stand Use, Andria M. Townsend

Cal Poly Humboldt theses and projects

In western North America, tree squirrels such as western gray (Sciurus griseus) and Douglas squirrels (Tamiasciurus douglasii) are potentially important prey for fishers (Pekania pennanti). Western gray squirrels in particular may be highly ranked due to their large body size. Masting trees including black oak (Quercus kelloggii) and tanoak (Notholithocarpus densiflorus) produce an important food source for tree squirrels; therefore, forest stands containing these trees may be useful to foraging fishers. I hypothesized that; 1) the abundance of western gray and Douglas squirrels in a stand is influenced by the …


Evaluation Of Restoration Techniques And Management Practices Of Tule Pertaining To Eco-Cultural Use, Irene A. Vasquez Jan 2019

Evaluation Of Restoration Techniques And Management Practices Of Tule Pertaining To Eco-Cultural Use, Irene A. Vasquez

Cal Poly Humboldt theses and projects

Tule (Schoenoplectus sp.) is a native plant commonly used by California tribes and Indigenous people throughout the world (Macía & Balslev 2000). Ecological, social and regulatory threats to its use in contemporary Indigenous culture highlight major issues concerning natural resource management. My ancestral homeland, what is now Yosemite National Park, stands as a figurehead in the intersection of land management and Indigenous peoples. An important element of Traditional Ecological Management (TEM) for quality basketry materials is prescribed fire, an element western science is increasingly acknowledging for creating a more biodiverse and heterogeneous landscape. This research was conducted in Mariposa and …


Spatial Variability In Recruitment Of Chilipepper Rockfish (Sebastes Goodei) In The California Current System, Laura K. Solinger Jan 2019

Spatial Variability In Recruitment Of Chilipepper Rockfish (Sebastes Goodei) In The California Current System, Laura K. Solinger

Cal Poly Humboldt theses and projects

Properly describing variability in population dynamics (e.g., growth, fecundity, recruitment) is expected to improve management of important fisheries stocks (Maunder & Piner, 2014). As recruitment to most fish stocks is determined during early life history stages (Houde, 1997; Iles & Beverton, 2000), and early life history stages are influenced by oceanographic conditions (Bjorkstedt et al. 2002; Laidig, 2010), understanding how environmental stochasticity influences recruitment deviations has potential to improve estimates of stock productivity and how productivity might change over time to support more effective management. Chilipepper Rockfish (Sebastes goodei) are an important commercial species that is managed as …


A Time- And State-Based Approach To Estimate Winter Movement And Survival Of Juvenile Coho Salmon (Oncorhynchus Kisutch) In Freshwater Creek, California, Nicholas Paul Van Vleet Jan 2019

A Time- And State-Based Approach To Estimate Winter Movement And Survival Of Juvenile Coho Salmon (Oncorhynchus Kisutch) In Freshwater Creek, California, Nicholas Paul Van Vleet

Cal Poly Humboldt theses and projects

Accounting for life history diversity and overwinter survival of juvenile Coho Salmon is important to inform restoration and recovery efforts for this threatened species. Multiple seaward migration patterns of Coho Salmon have been identified, including spring fry migrants, fall and winter parr migrants, and spring smolt migrants. Previous studies have indicated that spring smolt migrants have low overwinter survival rates while they are rearing in upstream habitats, suggesting that freshwater overwinter survival may be one factor that limits smolt production. However, previous research did not account for the early emigration of fall and winter parr migrants from the study area, …


Evidence For A New Search Behavior: Porcupines “Scout” For Winter Habitat During Summer In A Coastal Dune System, Pairsa N. Belamaric Jan 2019

Evidence For A New Search Behavior: Porcupines “Scout” For Winter Habitat During Summer In A Coastal Dune System, Pairsa N. Belamaric

Cal Poly Humboldt theses and projects

Species are often challenged by periodic changes in food availability and habitat quality. These environmental conditions may provide strong selective pressure for animals to strategically "scout" for important resources during periods of abundance, when exploratory movements are less costly. North American porcupines experience a drastic shift in forage quality from summer - a time of abundant, high quality forage - to winter, a nutritional bottleneck. I evaluated potential scouting behaviors of porcupines in Tolowa Dunes State Park, California using movement and habitat-use data. I compared summer and winter space use of porcupines using GPS data and monitored seasonal use of …


Achromatic Plumage Patch Quality: Internal Organ And Skeletal Correlates In Aleutian Cackling Geese (Branta Hutchinsii Leucopareia), Matthew D. Delgado Jan 2019

Achromatic Plumage Patch Quality: Internal Organ And Skeletal Correlates In Aleutian Cackling Geese (Branta Hutchinsii Leucopareia), Matthew D. Delgado

Cal Poly Humboldt theses and projects

Sexual selection theory predicts unique plumage patches signaling quality or status evolve via mate-choice and competition for mates. A growing body of research supports evidence that achromatic plumage patches may act as honest indicators of quality. Irregularities in these patches are attributed to an individual’s phenotypic and genotypic quality as well as environmental wear and tear. Aleutian cackling geese (Branta hutchinsii leucopareia) display achromatic plumage patches on their heads and necks, which may signal information about an individual’s attributes. I tested the honest advertisement and status signaling hypotheses by determining whether size and irregularities in the transition between …


Shade Trees Preserve Avian Insectivore Biodiversity On Coffee Farms In A Warming Climate, Sarah L. Schooler Jan 2019

Shade Trees Preserve Avian Insectivore Biodiversity On Coffee Farms In A Warming Climate, Sarah L. Schooler

Cal Poly Humboldt theses and projects

Coffee is an important export in many developing countries, with a global annual trade value of $100 billion. Climate change is projected to drastically reduce the area where coffee is able to be grown. Shade trees may mitigate the effects of climate change through temperature regulation for coffee growth, temperature regulation for pest control, and increase in pest-eating bird diversity. The impact of shade on bird diversity and microclimate on coffee farms has been studied extensively in the Neotropics, but there is a dearth of research in the Paleotropics. I examined the local effects of shade on bird presence and …


Contribution Of Juvenile Estuarine Residency In A Bar-Built Estuary To Recruitment Of Chinook Salmon (Oncorhynchus Tshawytscha), Emily Katherine Chen Jan 2019

Contribution Of Juvenile Estuarine Residency In A Bar-Built Estuary To Recruitment Of Chinook Salmon (Oncorhynchus Tshawytscha), Emily Katherine Chen

Cal Poly Humboldt theses and projects

Estuaries are commonly touted as nurseries for out-migrating salmonids, providing higher prey availability than streams, a physiological transition zone, and refugee from marine predators. Yet the diversity of estuaries makes it difficult to generalize the effect they have on salmonid recruitment. In bar-built estuaries, sandbars form at the mouth of rivers during periods of low flow, closing access to the ocean and disrupting outmigration. In this thesis, I evaluated how residency in a bar-built estuary affects the growth, survival, and ultimately recruitment of Chinook salmon (Oncorhynchus tshawytscha) in Redwood Creek, California. I conducted a mark-recapture experiment on out-migrating …