SLOSEA Graduate Fellows, “DEW” Lab Students, Interns, and Former Students

Current Students

Carolyn Ewers, SLOSEA Graduate Fellow

Undergraduate Degree: Cal Poly, B.S., Biological Sciences with a concentration in marine biology and fisheries. 2008.
Candidate, Cal Poly, M.S., Marine Biology. (Expected 2012)

Current Research & Interests: Characterizing eelgrass, Zostera marina, productivity to predict the effects of climate change on the Morro Bay ecosystem. After completing her Master’s degree at Cal Poly, Carolyn plans to pursue a PhD in Marine Biology focusing on the impacts of climate change to marine communities in order to inform management decisions on conservation and sustainability.

Nate Hall, SLOSEA Graduate Fellow

Undergraduate Degree: Cal Poly, B.S., Ecology and Systematic Biology with a concentration in marine biology and fisheries. 2006.
Candidate, Cal Poly, M.S., Marine Biology (Expected 2012)

Current Research & Interests: California Collaborative Fisheries Research Program and the Cal Poly CPFV Observer Program. Nate and his group conduct sampling and tagging of nearshore fish species with volunteer hook and line anglers aboard CPFVs (Commercial Passenger Fishing Vessels) and with traps aboard commercial fishing vessels in order to directly assess the effect of California marine reserves on nearshore fish populations. After completing his Master's degree at Cal Poly, Nate will pursue a career in marine research, preferably in California marine fisheries.

Lisa Needles, SLOSEA Graduate Fellow (Joint Cal Poly Master/ UCSB PhD Student)

Undergraduate Degree: Cal Poly, B.S., Ecology and Systematic Biology with a concentration in marine biology and fisheries.
Graduate Degree: Cal Poly, M.S., Marine Biology. 2007. Candidate, UCSB, PhD - Ecology, Evolution, and Marine Biology (Expected 2012).

Current Research & Interests: Community ecology, invasive species, trophic interactions, and endangered species. Her current research examines community dynamics in the context of invasive species. Lisa is also interested in factors and processes that affect community resistance to invasion and shape community assembles. Further, she studies the impacts invaders have on the recipient community, particularly in relation to the Southern Sea Otter.

Melissa Daugherty, DEW Lab Graduate Student

Undergraduate Degree: Cal Poly, B.S., Biological Sciences (Marine). 2006.
Candidate, Cal Poly, M.S., Marine Biology. (Expected 2012)

Current Research & Interests: Biofouling remediation and research. Using proteomics to investigate barnacle adhesion strength under various oceanic conditions, specifically monitoring changes in the expression of proteins found in the adhesive when barnacles are exposed to different rearing temperatures. Understanding the composition and biochemical properties of this underwater adhesive is relevant to biofouling research and will aid in developing more effective nontoxic materials used for antifouling and foul-releasing technologies. Interested in continuing to participate in marine science research, including marine education and public outreach.

Heather Montgomery, SLOSEA Policy Intern (Graduate)

Undergraduate Degree: CSU Sacramento, B.A., Government. 2002.
Candidate, Cal Poly, M.P.P. - Ocean & marine policy (Expected 2013)

Current Research & Interests: Heather is a policy graduate student, and has volunteered her time to help research issues surrounding the Central California Coast Seismic Imaging Project, as well as other coastal and marine issues that require research and a thorough understanding of the all the statutes, regulations, agencies and other stakeholders involved in resource management decision-making processes and administrative procedures involved with state and federal laws as well as policy initiatives. After graduation form the Public Policy program, she aims to work as an advocate or policy analyst for an environmental organization.

Former SLOSEA Fellows & Students

Sarah Johnson, Former SLOSEA Fellow

Graduate Degree: Cal Poly, M.S., Marine Biology. 2011.
Undergraduate Degree: Cal Poly, B.S., Biological Sciences. 2008.
Thesis Project: Living with Emerging Contaminants: Proteomics of 4-Nonylphenol Exposed Arrow Goby (Clevelandia ios)

Abstract: Alkylphenol ethoxylates (APEs) are widely used in industrial and household products as surfactants. APEs degrade into more toxic ethoxylates, such as 4-nonylphenol (NP), which has been shown to be an endocrine disruptor and enhance the growth of tumor cells. Nonylphenol is wider spread in Pacific estuaries than originally thought. Organisms in Morro Bay, California contain some of the highest concentrations of NP reported, while containing few other contaminants. As a benthic mud-dwelling fish, the arrow goby (Clevelandia ios) may be exposed to high levels of NP due to high contaminant sequestration rates in anaerobic mud. While ecotoxicology suggests that nonylphenol is in high concentration within C. ios tissues along with tissue level biological abnormalities, the molecular effects of nonylphenol on these fish have yet to be investigated. Utilizing proteomic techniques including two-dimensional gel electrophoresis and subsequent identification via MALDI-TOF/TOF mass spectrometry, there is evidence for change in expression of proteins involved in energy metabolism, biotransformation, regulation and cellular structure.

Related Publications:Diehl, J., Johnson, S,. Xia, K., West, A., Tomanek, L. The distribution of 4-nonylphenol in marine organisms of North American Pacific Coast estuaries. Chemoshphere (2012), doi: 10.1016/j.chemosphere.2011.12.040

Updates: Sarah is currently an Account Manager for one of the top five life science companies in the world.

Johanna Weston, Former SLOSEA Fellow

Graduate Degree: Cal Poly, M.S., Marine Biology. 2012.
Undergraduate Degree: University of Dallas, B.S., Biology. 2008.
Thesis Project: Quantification of Nitrate Sources and Sinks Using a Water Quality Network in Morro Bay Estuary, California

Abstract: Using an instrumented water quality network in Morro Bay Estuary, California from 2007 to 2010 (15min sampling frequency), this study addressed the two objectives of constructing a nitrate budget and assessing the influence of sampling frequency on water quality parameters. These two objectives led to the submission of an original report of research and a note to peer-reviewed journals.

The first objective was to characterize the high spatial and temporal variation in physical parameters and nitrate concentrations and to construct a nitrate budget quantifying sources and sinks of nitrate from the ocean, streams, and groundwater, as well as biological processes in the Estuary. Morro Bay Estuary was found to be a non-eutrophic system and a mean net exporter of nitrate. Fifty-four percent of the nitrate export was attributed to nitrate sources and internal biological processing. Nitrate loading from streams contributed 37 % to the export, while groundwater nitrate loading supplied a conservative estimate of 46 % of the exported nitrate with a neap tide enhancement of the discharge. Denitrification, Zostera marina, and benthic macroalgae assimilation of nitrate were the dominant internal biological processes for removal and retention, but were only 35% of the total nitrate budget.

The second objective was to investigate the impact of sampling frequency and sampling location on understanding dynamics in water quality by degrading a year time series of seven parameters from three water quality monitoring stations to sampling frequencies ranging from 15 minutes to 28 days. In Morro Bay Estuary, the semi-diurnal tidal cycle was the maximum component frequency driving the variability of temperature, turbidity, and dissolved oxygen concentrations. For these parameters, asymptotes were reached and sampling frequencies greater than six hours did not explain the additional variation in the parameters sampled. Whereas, salinity, turbidity, and nitrate concentrations lacked an asymptote, and decreased sampling frequencies led to increased estimated error. Sampling water quality parameters every 28 days can lead to mean annual difference of 30 – 140 % from 15 minute sample annual mean. We recommend sampling frequencies should be selected to oversample the tidal signal to at least hourly frequencies to capture diel cycles and episodic events that contribute significantly to understanding the variability in the estuarine physical and biological dynamics.

Updates: Johanna was awarded a 2012-2013 California Sea Grant State Fellowship, and will be working with the California State Water Resources Control Board’s Ocean Unit. Through this Fellowship she is gaining excellent experience in coastal and marine policy. After her Fellowship, she wishes to pursue a PhD in Oceanography and further develop her skills in both research and teaching while studying marine ecosystem dynamics with emerging technologies.

Leslie Longabach, Former SLOSEA Fellow

Graduate Degree: Cal Poly, M.S, Marine Biology. 2010.
Undergraduate Degree: UC Santa Barbara, B.S., Aquatic Biology. 2008.
Thesis Project: Movement of Selected Nearshore Temperate Reef Fishes Along California's Central Coast (Not, Living with Emerging Contaminants: Proteomics of 4-Nonylphenol Exposed Arrow Goby

Abstract: Worldwide fisheries decline has spurred the utilization of new conservation and management approaches, including the implementation of marine reserves. The diversity of goals and expected outcomes should guide the marine reserve design process, coupled with a thorough understanding of the ecology of all species targeted for protection. Central California’s network of coastal marine protected areas (MPAs) was established in an environment of some uncertainty regarding the expected outcomes for temperate nearshore fish species, especially the Sebastes genus (rockfishes). Movement behavior of temperate reef-fishes plays an important role in the level of protection that a reserve will afford a species. Consistent small-scale movements (<10 km) and limited home range sizes decrease the likelihood that individuals will encounter fishing mortality. Conversely, large-scale movements outside of reserve boundaries may contribute to fisheries in surrounding waters (‘spillover’).

The current study sought to further elucidate the movement behavior of some shallow-water temperate reef fish species throughout California’s central coast, with goals of providing useful data for future MPA design processes. Tag-and-recapture methodology was utilized in order to observe fish movements, centered on a public participation program for acquiring information on recaptured tagged fishes. A total of 476 fishes representing 14 species were recaptured from a sample of 37,111 tagged (1.3%) over a five-year period spanning 2005-2009. The majority (75%) of distances traveled were less than one kilometer, however some species made consistent far-ranging travels on the order of hundreds of kilometers as well. Analyses of factors with potential for shaping movement behavior included geographic variation, source of recapture data,gear type, days at liberty, length, initial capture depth, handling condition, and fish density. Additionally, the applicability of tag-and-recapture methodology is examined as an effective source of fish movement information. The results of this research corroborate findings of previous studies as well as provide new insight into the movement patterns of some nearshore temperate reef species.

Updates: Leslie is currently working for Americorps as an environmental manager in remote Peruvian villages.

Loredana Serafini, Former SLOSEA Fellow

Graduate Degree: Cal Poly, M.S., Marine Biology. 2011.
Undergraduate Degree: Cal Poly, B.S,. Biological Sciences . 2008.
Thesis Project: The proteomic response of sea squirts (Ciona congeners) to heat stress: Evidence for differential thermal sensitivities

Abstract: The sea squirts Ciona intestinalis and C. savignyi have disparate distribution patterns, which may result from differences in their thermal tolerance limits. Because C. intestinalis, an almost cosmopolitan species, has a more widespread distribution, it is thought that it is better adapted to endure a wide range of temperatures. In order to compare the heat stress response between these two congeners, we studied global changes in protein expression, using a proteomics approach. To characterize the response to extreme heat stress, animals of both species were exposed to temperatures of 22°C, 25°C, and 28°C for 6 h, and then were left to recover at a control temperature (13°C) for 16 h. An additional experiment was conducted to assess the effect of mild-to-moderate heat stress including a 6 h exposure to temperatures of 18°C, 20°C, and 23°C, and a 16 h recovery at a control temperature (16°C). A quantitative analysis, using 2D gel electrophoresis and gel-image analysis, showed that in the high heat stress (HHS) experiment, 15% and 18% of the all protein spots detected demonstrated changes in expression in C. intestinalis and C. savignyi, respectively. In the low heat stress (LHS) experiment, 4% of the total number of proteins detected changed significantly in both C. intestinalis and C. savignyi. Using matrix-assisted laser desorption ionization (MALDI) tandem time-of-flight mass spectrometry, we were able to identify proteins with a 65-100% success rate, depending on species. Our results indicate that C. intestinalis maintains higher baseline levels of molecular chaperones and launches a quicker response to thermal stress than C. savignyi, suggesting it may be the more thermally tolerant of the two. In addition, actins, tubulins, and ATP-synthase F1 ß-subunits were the most susceptible to proteolytic degradation, which may indicate that they have relatively higher thermal sensitivities.

Updates:Loredana is currently pursuing a career in the biotechnology industry and works in a laboratory environment.

Grant Waltz, Former SLOSEA Fellow

Graduate Degree: Cal Poly, M.S., Marine Biology. 2012. (pending)
Undergraduate Degree: UC Riverside, B.S., Biological Sciences. 2005.
Thesis Project: An analysis of Human Disturbance to Rocky Intertidal Communities in San Luis Obispo County.

Abstract: TBA

Updates: Grant has continued to pursue research related to California marine environments, particularly related to marine protected areas, such as research work with the Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO) and with SLOSEA, including the California Collaborative Fisheries Research Project.

Corbin Hodges, Former “DEW” Lab Graduate Student

Graduate Degree: Cal Poly, M.S., Marine Biology. 2009.
Undergraduate Degree:
Thesis Project: Dissoloved organic matter influences the time of embryonic development of the purple sea urchin (Strongylocentrotus purpuratus)

Abstract: Marine dissolved organic matter (DOM) comprises one of the largest carbon reservoirs on earth and has long been considered a potential energy source for marine invertebrates. The importance of DOM transport has been adequately demonstrated for unicellular organisms, where DOM can meet 100% of an organisms energy needs, but the effects of DOM uptake for marine metazoans are less well understood. In this study, three general areas involving the influence of DOM transport to marine invertebrates were explored. First, we assessed the effects of using seawater exposed to high intensity ultraviolet radiation (UVR) on the study organism; embryos of the purple sea urchin, Strongylocentrotus purpuratus. This was important because we used seawater treated in this way to create water types used in the experiments. Exposing seawater to high intensity UVR oxidizes (and functionally removes) DOM in the seawater. Second, the influence of the presence of DOM on the timing of embryonic development was examined for embryos of S. purpuratus. Specifically, the time of cell division and the time of hatching were determined for embryos in seawater with and without DOM. Finally, the ability of DOM to moderate the negative effect of UV-exposure on time of cell division was assessed. To make these comparisons experiments were performed using three water types: FSW (0.22 micron filtered seawater), DOM-depleted seawater (UV oxidized 0.22 micron filtered seawater), and DOM-enriched seawater (UV oxidized 0.22 micron filtered seawater enriched with labile DOM). In the first experiment, batches of embryos in the three water types were either exposed or not exposed to ultra-violet radiation and the time of first cell division was compared for embryos across the six treatments. In the second experiment, batches of embryos were placed in the same three water types and the time of first cell division and the time of hatching were quantified. From these experiments several results were generated. First, seawater exposed to high intensity UVR did not influence the timing of development of embryos of S. purpuratus. Embryos in water exposed to high intensity UVR (DOM-enriched and DOM-depleted seawater) hatched at similar times and completed first cell division at times similar to embryos in water not exposed to high intensity UVR (FSW). Next, we found that the influence of the presence of DOM on the development timing of S. purpuratus embryos depended on the event that was examined. The time of first cell division was not affected by the presence of DOM but the time of hatching was. Embryos in water with dissolved organic matter hatched on average 86 minutes later than embryos in water without DOM. Potentially, embryos in seawater without DOM speed up development to more quickly reach the point that they can feed on particulates. Lastly, the presence of DOM did not influence UVR-induced cleavage delay. The percent cleavage delay was not significantly different for embryos in seawater with (DOM-enriched) and without (DOM-depleted) DOM. In addition to the experiments, all studies in the literature that examine the realized effects of DOM transport were analyzed to ascertain when the manifestation of DOM uptake is most likely to occur. From these results, it appears that the effects of DOM transport are most likely to manifest after the life stage in which the majority of uptake occurred. If DOM transport has an affect within a life stage it is most likely to manifest as moderation of biomass loss or maintenance of endogenous reserves. With the addition of the experimental results from this study to the information already in the literature we begin to more fully grasp the importance of DOM transport to S. purpuratus. DOM influences the time of hatching, biomass, arm length, and stomach size of the species; results that highlight the importance of examining multiple affects of DOM transport for a single species. In conclusion, future research should look for multiple effects of the presence of DOM both within and across life stages (for a single species) to better understand the importance of DOM to marine invertebrates.

Updates: After spending a year abroad teaching English, Corbin has returned to Cal Poly to lecture in the Biological Sciences Department, and assist graduate and undergraduates with their research projects.

David Rasmussen, Former SLOSEA Fellow

Graduate Degree: Cal Poly, M.S., Marine Biology. 2010.
Undergraduate Degree:
Thesis Project: Comparisons of Fish Species Inside and Outside of Marine Protected Areas Off the South Central Coast of California

Abstract: From 2004-2008 and 2008-2009 Cal Poly University researchers conducted two separate tag and recapture studies of nearshore fish populations along California’s central coast. Three locations were sampled that have experienced different degrees of fishing pressure. Big Creek MPA has been closed to all fishing from 1993 onwards and is the farthest from port of all locations. Cambria lies closest to port of the three locations and because of this has the highest fishing pressure. Piedras Blancas lies midway between Cambria and Big Creek. Portions of Cambria and Piedras Blancas were designated as MPAs in 2007. Sampling protocols of these two different studies differed in bait used and size of commercial fish trap. An experiment was conducted to simultaneously compare the different trapping and baiting protocols from the prior studies to find a conversion factor that related catch per unit effort (CPUE), length frequency distributions and captured fish diversity between the two studies, thus providing a means to connect the two data sets for stock assessments and baseline MPA monitoring.

Our sampling showed no significant difference in mean fish length or diversity between the two protocols for the five most common nearshore fish species captured, and three of the five species showed no significant difference in CPUE. Cabezon (Scorpaenichthys marmoratus), showed a significantly lower CPUE (50.5%) using the MLPA monitoring protocols compared to the commercial fishing protocol and black and yellow rockfish (Sebastes chrysomelas) had a significantly higher CPUE (310%) using the MLPA monitoring protocol. These findings provide a means of maintaining data continuity across the entire sample region and inclusion of earlier projects in the analyses of nearshore fish populations of the region.

With the linkage of these two studies we provide important baseline data for the Cambria MPA from before it was established in 2007. Fish populations were compared on a year-to-year basis within each location, and between the different locations. I found several main factors helped to explain differences in size and abundance across time within individual locations, and across the three locations. These factors were inherent differences in habitat, establishment of MPAs, and changes in fishing pressure and post-larval recruitment.