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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

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 ...


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

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 single population throughout the continental US (Field et al. 2015), yet spatiotemporal heterogeneity of oceanographic conditions is likely to cause variability in recruitment deviations throughout this range. Field and Ralston (2005) used region-based catch-at-age data ...


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

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 ...


The Effects Of Ocean Acidification And Reduced Oxygen On The Behavior And Physiology Of Juvenile Rockfish, Corianna H. Flannery Jan 2018

The Effects Of Ocean Acidification And Reduced Oxygen On The Behavior And Physiology Of Juvenile Rockfish, Corianna H. Flannery

Theses and projects

As climate change progresses, the frequency and duration of upwelling events that bring low pH, low dissolved oxygen (DO) water to nearshore habitats are expected to increase. In addition, long-term global changes in ocean pH and DO are expected to occur within the next few decades to centuries. Locally, there have been documented reductions in near-shore pH along with the expansion of oxygen minimum zones within the California Current System. However, very few studies have investigated the potential interactive effect of these stressors on temperate reef fish. For this thesis, two sets of laboratory experiments were conducted to determine the ...


The Interactive Effects Of Ocean Acidification, Food Availability, And Source Location On The Growth And Physiology Of The California Mussel, Tharadet Daniel Man Jan 2018

The Interactive Effects Of Ocean Acidification, Food Availability, And Source Location On The Growth And Physiology Of The California Mussel, Tharadet Daniel Man

Theses and projects

Research shows ocean acidification (OA) can have largely negative impacts on marine organisms and ecosystems. Prior laboratory studies show that shelled marine invertebrates (e.g., molluscs) exhibit reduced growth rates and weaker shells when experiencing OA-related stress. However, populations of the critical intertidal mussel species, Mytilus californianus, which experience naturally acidic water due to upwelling in certain parts of Northern California have been observed to have relatively stronger and thicker shells and higher growth rates than those that experience less frequent exposure to upwelling. To address the discrepancies between negative effects of OA exposure in the laboratory and seemingly positive ...


Negatively Correlated Abundance Suggests Competition Between Red Abalone (Haliotis Rufescens) And Red Sea Urchins (Mesocentrotus Franciscanus) Inside And Outside Established Mpas Closed To Commercial Sea Urchin Harvest In Northern California, Johnathan Centoni Jan 2018

Negatively Correlated Abundance Suggests Competition Between Red Abalone (Haliotis Rufescens) And Red Sea Urchins (Mesocentrotus Franciscanus) Inside And Outside Established Mpas Closed To Commercial Sea Urchin Harvest In Northern California, Johnathan Centoni

Theses and projects

Red abalone and sea urchins are both important herbivores that potentially compete with each other for resources like food and space along the California coast. Red abalone supported a socioeconomically important recreational fishery during this study (which was closed in 2018) and red sea urchins support an important commercial fishery. Both red sea urchins and red abalone feed on the same macroalgae (including Pterygophora californica, Laminaria setchellii, Stephanocystis osmundacea, Costaria costata, Alaria marginata, Nereocystis leutkeana), and a low abundance of this food source during the period of this project may have created a highly competitive environment for urchins and abalone ...


Predictive Mapping Of Two Nearshore, Demersal Fish Species On Northern California Reefs Using Scuba-Based Visual Surveys And Remote Sensing, Christopher H. Teague Jan 2018

Predictive Mapping Of Two Nearshore, Demersal Fish Species On Northern California Reefs Using Scuba-Based Visual Surveys And Remote Sensing, Christopher H. Teague

Theses and projects

California's shallow rocky reefs provide critical habitat for a diverse assemblage of fishes. Effective management strategies for these species require both accurate stock assessments as well as a spatially explicit understanding of the relationship between fishes and characteristics of their habitat. We used a generalized additive model framework to create spatially predictive maps of the abundance and biomass of two demersal fish species prevalent on northern California reefs: lingcod (Ophiodon elongatus) and kelp greenling (Hexagrammos decagrammus). These models incorporated data from SCUBA-based fish and habitat surveys at depths from 12-26 meters as well as measures of seafloor topography derived ...


Characterizing Habitat Preference In Three Nearshore Reef-Associated Fishes Through Collaborative Research, Public Data, And Open Source Software, Ian D. Kelmartin Jan 2018

Characterizing Habitat Preference In Three Nearshore Reef-Associated Fishes Through Collaborative Research, Public Data, And Open Source Software, Ian D. Kelmartin

Theses and projects

Black rockfish (Sebastes melanops), canary rockfish (S. pinniger), and lingcod (Ophidion elongatus) are important species in Northern California’s nearshore recreational and commercial fisheries. These species are associated with nearshore rocky reefs and are among a suite of species intended to benefit from the establishment of the marine protected area (MPA) network along the Northern California Coast in 2012.

Many aspects of the North Coast’s nearshore ecosystem remain poorly studied, including the spatial distribution and habitat associations of nearshore fish species. This study used data collected from Cape Mendocino State Marine Reserve (SMR), Ten Mile SMR, and paired, nearby ...


Seasonal Fish And Invertebrate Communities In Three Northern California Estuaries, Katherine Osborn Jan 2017

Seasonal Fish And Invertebrate Communities In Three Northern California Estuaries, Katherine Osborn

Theses and projects

The majority of Northern California estuaries are small, flooded, river valleys that are largely unstudied due to their small sizes and remote locations. Yet these estuaries serve as important nursery areas for many marine fish species including rockfish, flatfish, smelt, and herring, and they are vital to anadromous species such as Chinook Salmon (Oncorhynchus tshawytscha) and Steelhead (O. mykiss). I sampled the summer and winter fish and invertebrate communities of the Big, Mad, and Ten Mile river estuaries. Fish were sampled via beach seine or fyke net and invertebrates were sampled via benthic cores, June 2014-June 2016.

This research is ...


Multiscale Habitat Suitability Modeling For Canary Rockfish (Sebastes Pinniger) Along The Northern California Coast, Portia N. Saucedo Jan 2017

Multiscale Habitat Suitability Modeling For Canary Rockfish (Sebastes Pinniger) Along The Northern California Coast, Portia N. Saucedo

Theses and projects

Detailed spatially-explicit data of the potential habitat of commercially important rockfish species are a critical component for the purposes of marine conservation, evaluation, and planning. Predictive habitat modeling techniques are widely used to identify suitable habitat in un-surveyed regions. This study elucidates the predicted distribution of canary rockfish (Sebastes pinniger) along the largely un-surveyed northern California coast using data from visual underwater surveys and predictive terrain complexity covariates. I used Maximum Entropy (MaxEnt) modelling software to identify regions of suitable habitat for S. pinniger greater than nine cm in total length at two spatial scales. The results of this study ...


Population Characteristics And Trophic Interactions Between Pacific Mole Crabs And Redtail Surfperch On Northern California Sandy Beaches, Michelle Lynn Succow Jan 2017

Population Characteristics And Trophic Interactions Between Pacific Mole Crabs And Redtail Surfperch On Northern California Sandy Beaches, Michelle Lynn Succow

Theses and projects

A network of marine protected areas (MPAs) was established to protect northern California coastal habitats in December 2012. Populations of two indicator species, Amphistichus rhodoterus (redtail surfperch) and Emerita analoga (pacific mole crabs) were characterized within MPAs and reference sites to provide baseline ecological information for this region. Data were gathered using a series of simple field surveys (hook and line fishing surveys for A. rhodoterus along with core and transect surveys for E. analoga). Relative abundance, lengths, and sex ratios of A. rhodoterus did not differ between MPAs and their respective reference sites, whereas condition (overall health) increased in ...


Economic Effects Of Pacific Halibut Closures On Businesses On The North Coast And The Age, Growth, And Reproductive Status Of Pacific Halibut In Northern California And Central Oregon, Miki Takada Jan 2017

Economic Effects Of Pacific Halibut Closures On Businesses On The North Coast And The Age, Growth, And Reproductive Status Of Pacific Halibut In Northern California And Central Oregon, Miki Takada

Theses and projects

Traditionally, the recreational fishery for Pacific halibut has been open in California from 1 May through 31 October. In 2014, however, the Pacific halibut fishery was closed in California during the month of August for the first time in history in an effort to reduce harvest and bring total catch closer to what is allocated to our region by the Pacific Fisheries Management Council (PFMC) Catch Sharing Plan. To determine the effects that the closure had on businesses along the North Coast, I conducted an economic impact survey in 2014. The results of the survey showed that fishing-related businesses lost ...


Telonicher Marine Laboratory, Hsu Telonicher Marine Laboratory Jul 2016

Telonicher Marine Laboratory, Hsu Telonicher Marine Laboratory

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No abstract provided.


Telonicher Marine Laboratory, Hsu Telonicher Marine Laboratory Apr 2016

Telonicher Marine Laboratory, Hsu Telonicher Marine Laboratory

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No abstract provided.


Telonicher Marine Laboratory, Hsu Telonicher Marine Laboratory Oct 2015

Telonicher Marine Laboratory, Hsu Telonicher Marine Laboratory

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No abstract provided.


Telonicher Marine Laboratory, Hsu Telonicher Marine Laboratory Jul 2015

Telonicher Marine Laboratory, Hsu Telonicher Marine Laboratory

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No abstract provided.