Special Thanks to San Lorenzo Valley Water Department and San Lorenzo Valley Unified School District for their support.
Owens, Natalie T. and Cambron, Trevor W.
SOD: Is it Still Spreading? What’s going on?
Phytophthora ramorum is a water mold which causes Sudden Oak Death (SOD) in Shreeve oak, coast liveoak, canyon live oak, California black oak, and tanoak. First observed in Marin County in the 1990’s, the disease has since spread south to Monterey County, and as far north as Oregon. It is a disease which threatens the viability of oak woodlands and tanoak-redwood woodlands of Santa Cruz county. This pathogen will not only kill tanoaks but will use tanoaks to help further spread the infection. This year, our objective is to determine the state of SOD in the tanoak-redwood forest behind San Lorenzo Valley High School (SLVHS). We also want to assess how P. ramorum infections are affecting the growth of tanoaks, large and small. We hypothesize that at least ⅕ of the trees we test will be infected with SOD. First, we set up a plot, 100 X 30 meters in the forest behind SLVHS. We randomly chose 25 trees within our plot to test for SOD. We are using Immunostrips to determine if the tanoaks have SOD or not. Before we test with the Immunostrips, we ranked the trees on a scale of 0-10, with 0 being completely healthy and 10 being totally dead, based on their foliar symptoms of SOD. We have also initially recorded the Diameter at Breast or Base Height(DBH) and height of each of the 25 tanoaks to be able to follow their long-term growth. We tested our 25 trees with the Immunostrips and discovered that 4 of the 25 trees are infected with SOD. Trees 23, 27, 41, and 78 tested positive on the Immunostrips. Tree number 41 had a very faint second line on the strip which indicates that the infection of SOD is a small amount. We can conclude that SOD is still spreading in the forest behind SLVHS because we found the infection in the tanoaks as well as in a Bay Laurel just outside of our plot. We are going to continue monitoring the growth of our tanoaks and compare the infected to the uninfected. We would like to thank our mentor Dr. Michael Loik, UCSC for his assistance.
Robinson, Celeste and Lozier, Katelyn
Mussels and Sea Stars: A Constant Battle
Our goal of monitoring the Mussel Plot at Davenport Landing, is to explore how sea star and mussel populations are interdependent on each other. We hypothesize that, as sea star populations recover from the mass mortality event caused by sea star wasting syndrome (2013), mussel populations will begin to decrease. This is due to the fact that sea stars are the major predators of mussels in the rocky intertidal zone. Once or twice a month, during low tides, we collect data on the abundance of sea stars and mussels following the LiMPETS protocols. We use a previous LiMPETS data set (1976-2014) to determine the relationship, if any, between sea star abundance and mussel abundance. The data shows that the mussel populations fluctuated from 1976 to 2014, and now in 2016 are at their highest. The sea star population decreased from 2009 to 2014 and populations of sea stars are now increasing. We conclude that, since the mussel populations stayed about the same while the sea star numbers decreased to near zero, then increased, sea star abundance may not be a major influence on mussel abundance. However, as the sea star numbers increase, and grow to larger sizes, they may eventually reduce the high abundance of mussels now found in our plot. We would like to thank John Pearse and Emily Gottlieb for their assistance.
Keesaw, Natalie J. and Sophia E. Magliato
Are Mussels Dissolving in the Tidepools?
Over the past two years, we have been have been monitoring the tidepools at Davenport Landing Beach. Last year, we discovered that storms generated by El Niño and the Blob disrupted the abundance and distribution of Honeycomb Tube Worms, a spatial indicator species, at the site. This year, we are focusing on whether increasing ocean acidification is lethal to mussels in tidepools by inhibiting shell production. Ocean Acidification has been increasing for the last 200 years due to the increase of atmospheric carbon dioxide from human emissions. Carbon dioxide is absorbed into seawater forming carbonic acid lowering ocean pH. This increasing acidity is impeding calcium carbonate shell building processes of mollusks. Mussels are a significant food source and space competitor in the tidepool ecosystem. If their numbers decrease, this could affect ecosystem biodiversity. We monitor twice a month, following LiMPETS (Long-term Monitoring Program and Experiential Training for Students) procedures for the Vertical Transect site at Davenport Landing. We are measuring pH and alkalinity from four tidepools adjacent to our transect. Worldwide ocean pH averages about 8.1-8.2. We are finding that the pH in the tidepools is ranging from 7.08-7.89. We are measuring alkalinity to determine the buffering capacity of the water which could mediate the decrease ofpH. We are continuing to collect data in order to further support our hypothesis. We would like to thank ourmentors Dr. John Pearse (UCSC) and Emily Gottlieb (LiMPETS) for their assistance and advice.
Le Roux, Aiden, Nate Alisago, Jared Rembao
Sustainability of Olympia Watershed: Can Humans and Wildlife Coexist?
We have been collecting data on what animals are frequenting Olympia Watershed using camera traps since October 2015. Olympia Watershed is part of the Sandhills Chaparral, a unique environment found solely in Santa Cruz County, and an important aquifer site for the San Lorenzo Valley Water District (SLVWD). Last year, we analyzed the biodiversity of the area based on camera trap data. This year we are going to compare data from our site, to a similar, but less human-impacted site at Laurel Curve. Wildlife Ecologist Tanya Diamond and Wildlife Researcher Ahiga Snyder have been collecting camera trap data at Laurel Curve site for the last year. The difference between Olympia Watershed and Laurel Curve is the amount of human recreational activity: the Watershed site has many dog-walking paths and horses, while Laurel Curve has very minimal human impact. Our question is how will human recreational activities impact the abundance mammalian species in the Santa Cruz Sandhill environment. We monitor bimonthly, collecting data from 4 camera traps in Olympia Watershed. We are currently comparing our database with the Laurel Curve data, which will allow us to then construct a conclusion about the impact of human recreational activities on the Sandhills environment, and how we might diminish this impact. We would like to thank the San LorenzoValley Water District for their financial help, and Tanya Diamond, Ahiga Snyder, and Bryan Largay for theirinvaluable assistance.
Ackemann, Cassie, Annika Bauerle, and Ava Badger
What’s The Stink In Shingle Mill Creek: Act III
Shingle Mill Creek has been identified as a non-pointsource of fecal coliform pollution into the San Lorenzo River. In past years, we have determined that the coliform originates from an upstream location, where the density of houses is the highest. This year, our investigative question is to continue to determine the source of the fecal bacteria contamination in Shingle Mill Creek. We hypothesize that the coliform is most likely coming from faulty septic systems, as coliform bacteria can easily leach through the relatively sandy soil present along Shingle Mill Creek. To further pinpoint the source of contamination, we have begun this year to monitor the ammonia levels in the creek, which can be indicative of malfunctioning septic systems. We collect water samples bimonthly from five sites along the creek. In the lab, we use membrane filtration technique and are incubating our filters on a media which is specific for E. coli and total coliform. We have had three samples analyzed for caffeine concentrations, all of which have come back negative. We are also collecting rainfall data; high rainfall events should correlate with septic system failure and higher bacterial levels. This year, we continue to find increased E. coli contamination upstream, but our nitrate and ammonia levels are so far inconclusive. We are continuing to monitor before and after rainfall events and hypothesize that fecal coliform, caffeine, ammonia, and nitrate levels will increase with rainfall. We would like to thank Steve Peters, Matt Bessee, Jennie Munster, and Sam Blakesley for their invaluable support and assistance.
Welch, Ashley, Maxwell Zinkievich
Using a More Sustainable Method of Data Collection to Determine The Effect of the Pacific Decadal Oscillation on Air Quality in the San Lorenzo Valley
Our purpose this year is two-fold: investigating the role of the PDO (Pacific Decadal Oscillation) on atmospheric inversions and developing a lower cost, more sustainable method of collecting atmospheric data. Last year, we determined that the frequency and strength of atmospheric inversions in the San Lorenzo Valley were influenced by El Niño-caused sea surface temperature increases. This year, we are researching whether a longer term oceanic-atmospheric event, the PDO, affects the frequency of inversions and concentration of PM 2.5 (particulate matter less than 2.5 microns in diameter) which has a detrimental effect on human respiratory health. Every 20-30 years, when the PDO shifts from a warm phase (negative) to a cool phase (positive), we hypothesize that there will be a decrease in both the strength of inversions, and the number of days in which air quality standards for particulate matter are exceeded. To support this hypothesis, we are correlating historical temperature data to the number of PM 2.5 exceedances in order to extend our data to include several oscillations of the PDO. Our second mission is to eliminate the need for expensive, consumable helium balloons and radiosondes, as well as modernize the data collection process. We have already re-engineered the data collection package, and are working on obtaining a drone to test as a launch vehicle. We are continuing to use the standard data collection and launch system to obtain our inversion measurements, until we have thoroughly tested and perfected our alternative method. We would like to thank Bob Nunes and Scott Norton from the Monterey Bay Unified Air Pollution Control District for their time and technical assistance.
Manseau, Julianna, Kate Ussat, & Ellie Bourret
What’s Increasing the Crow and Raven Populations? Is it the Garbage?
We monitor the bird species of San Lorenzo Valley High School and the surrounding areas in order to compare the diversity and abundance of birds and the changes in the raven and crow populations due to the presence of human garbage. Our hypothesis is that the more open garbage cans in an area, the greater the population of crows and ravens in that area. The increase in raven and crow populations could be lowering the biodiversity of the ecosystem because of their niche as nest predators. Within each of our three study areas – San Lorenzo Valley High School and two neighborhoods – we have designated nine circular, fifty meter radius plots separated by at least one hundred meters to avoid duplicate bird counts. We monitor three times a week, covering all the areas. A bird is recorded in our data sheet, if the bird is heard, seen, or flushed from the plots. We also record abiotic factors at each plot, such as temperature and cloud cover. We have been monitoring since September 2016, and are analyzing our data to determine if it supports our hypothesis. Last year, starting October 2015, we not only learned to bird by sight, voice, and flyover but determined that bird abundance at the high school is related to distance from Hwy 9, proximity to Fall Creek forest, and % vegetation cover in each plot. As birds are key indicator species, this project informs us about the diversity of species and the environmental health of the Felton area. We would like to thank our mentors, Alex Rinkert and Jeff Smith, for their advice and bird expertise.
Gallagher, I., Davis, H., Lydon, Q.
Blooms in the Bay: Is Arana Gulch Guilty?
We are monitoring the abundance and diversity of phytoplankton in Santa Cruz Harbor to determine correlations between temperature, turbidity, ammonium, and the likelihood of a toxic phytoplankton bloom. Through our previous research, we determined there was a relationship between salinity, caused by upwelling, and phytoplankton abundance, but this was not definitive. This year, we are investigating another variable impacting phytoplankton abundance: nutrient runoff from Arana Gulch. If the Arana Gulch discharge is high in nutrients, as measured by ammonium concentrations, this could cause an algal bloom, which can be harmful to humans and the marine environment. We commute bi-monthly to Santa Cruz Harbor where we use a 20 micron phytoplankton net to retrieve our phytoplankton samples and record environmental data using thermometers, refractometer, and a secchi disk. In the lab, using a microscope, we determine the type and abundance of phytoplankton species in our samples. We also mail phytoplankton samples to the California Department of Public Health for their analysis of the presence or absence of harmful algal blooms species (HABS). We are analyzing ammonium levels at UCSC’s Ocean and Marine Sciences Lab. We also collect water color using Forel-Ule and the Munsell color system for the Santa Cruz Water Colors project, a regional effort to compare ocean color and phytoplankton occurrence. Finally, we are maintaining a blog, in conjunction with UCSC, to communicate our findings to the community. We have yet to collect and analyze enough samples to make any definitive conclusions from our data. We would like to thank our mentors, Kendra Negrey and Vanessa Zubkousky, for their invaluable assistance.
Hill Carly and Mira Lion
Effect of Acanthocephalan Parasites on the Burrowing Behavior of Emerita analoga Or “Are Spiny-Headed Worms turning Sand Crabs into Zombies?”
Sand crabs are generally regarded as an indicator species of the health of sandy beach ecosystems. Sandcrabs (Emerita) are also the intermediate hosts of spiny-headed worms (acanthocephalan parasites) that can be deadly to seabirds and marine mammals such as otters when ingested. The goal of our project this year is to determine if there is a correlation between the depth the sand crabs burrow and abundance of spiny-headed worms in Emerita. Our hypothesis is that there will be more parasites in sand crabs that are closer to the surface. We surmise that the worms are altering the behavior of the sand crabs, causing them to rise to the surface, making them more vulnerable to predation by shorebirds, the direct host of the parasite. We are continuing to gather data monthly on number and sex of sand crabs at Seabright beach following LiMPETS protocols. Beginning summer 2015, we started collecting and dissecting sand crabs to quantify the acanthocephalan parasite load and if there was a pattern related to the 15-16 El Niño event. We found thatsea surface temperature does not appear to affect abundance of the parasites. To test this year’s hypothesis, we are still following LiMPETS protocols, but we are also recording the depth at which we recover the sand crabs to ascertain if there is a relationship between parasite load and distance from the surface, which could indicate that the parasites are modifying the behavior of the sand crab in order to complete the parasite’s life cycle. So far, our data is inconclusive as to whether or not sand crabs are found closer to the surface of the sand when they have a heavier parasite load. We would like to thank Emily Gottlieb and Dan Merritt who have assisted us with this project.