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Articles 1 - 14 of 14

Full-Text Articles in Life Sciences

Comparison Of An Endangered Species’ Seed Bank Before And After Ungulate Removal, Melanie K. Phillips, Kathryn Mceachern Sep 2018

Comparison Of An Endangered Species’ Seed Bank Before And After Ungulate Removal, Melanie K. Phillips, Kathryn Mceachern

STAR (STEM Teacher and Researcher) Presentations

The purpose of this study was to assess the impact of the removal of ungulates on the soil seed bank of the endemic Santa Rosa Island manzanita (Arctostaphylos confertiflora). A. confertiflora was trampled and browsed by non-native ungulates between the years 1850 and 2011 which reduced its ability to produce seeds.This species is an obligate seeder, meaning that sprouting from seeds in the soil is its only method of reproduction. Due in part to the lack of its soil seed bank, this species was federally listed as endangered by the US Fish and Wildlife Service in 1997. In order ...


Impacts Of Nutrient Enrichment On Native And Non-Native Plants In Serpentine Soil, Amber R. Williams, Mary Devlin, N. Rajakaruna Aug 2018

Impacts Of Nutrient Enrichment On Native And Non-Native Plants In Serpentine Soil, Amber R. Williams, Mary Devlin, N. Rajakaruna

STAR (STEM Teacher and Researcher) Presentations

Serpentine soil, derived from serpentinite, California’s state rock, is characterized by its harsh nature - due to its low levels of essential nutrients and exceptionally high levels of toxic heavy metals.In California, serpentine soils are characterized by high levels of plant endemism and rarity. Plants occurring in serpentine soil exhibit extreme tolerance of harsh soil conditions, and are typically out-competed in ‘normal’ soils due to the cost associated with physiological specialization. Atmospheric nutrient deposition is contributing to a greater invasion of non-native grass species on serpentine soils, outcompeting the native species and threatening them with local extinction. Our greenhouse ...


Ecological And Organic Life Safety Concerns Of Hfo-1234yf, Alberni V. Ruiz Aug 2017

Ecological And Organic Life Safety Concerns Of Hfo-1234yf, Alberni V. Ruiz

STAR (STEM Teacher and Researcher) Presentations

While at NOAA my research was directed by the inquiry of whether or not HFO-1234yf, a new compound being introduced into coolant system and replacing greenhouse gases HFC, is harmful to organic life. Using the computer program Matlab I was able to develop figures that represented the concentration of HFO-1234yf (HFO) in 12 different tower locations throughout the country. Comparing and contrasting concentrations of this HFO compound at each site led me to the question the possible harmful side effects this compound could bring to organic life due to the fact that concentration levels are increasing, with one factor being ...


Automated Detection Of Deep-Sea Animals, Dallas J. Hollis, Duane Edgington, Danelle Cline Jul 2016

Automated Detection Of Deep-Sea Animals, Dallas J. Hollis, Duane Edgington, Danelle Cline

STAR (STEM Teacher and Researcher) Presentations

The Monterey Bay Aquarium Research Institute routinely deploys remotely operated underwater vehicles equipped with high definition cameras for use in scientific studies. Utilizing a video collection of over 22,000 hours and the Video Annotation and Reference System, we have set out to automate the detection and classification of deep-sea animals. This paper serves to explore the pitfalls of automation and suggest possible solutions to automated detection in diverse ecosystems with varying field conditions. Detection was tested using a saliency-based neuromorphic selective attention algorithm. The animals that were not detected were then used to tune saliency parameters. Once objects are ...


Winter Freeze Decreases The Emergence Of Fauna And Flora In California Vernal Pools, Korena S. Hendryx, Jamie Kneitel Aug 2015

Winter Freeze Decreases The Emergence Of Fauna And Flora In California Vernal Pools, Korena S. Hendryx, Jamie Kneitel

STAR (STEM Teacher and Researcher) Presentations

Impacts of global climate change is observed in many ecological systems. Temporary aquatic ecosystems, including California vernal pools, are especially sensitive to climatic variation, but most species are adapted to the annual fluctuations in precipitation and temperature. Since vernal pools experience an inundation and desiccation every year, species that occupy the ecosystem have adaptations to this cycle. Many species survive drought by creating resting eggs to then re-emerge upon inundation However, climate changes outside the typical range may have deleterious effects on these populations. Moreover, climate variation can have secondary effects on the community. For example, the amount of precipitation ...


Radiocarbon Isotopic Classification Of Deep Tropical Forest Soils, Brooke Butler, Karis J. Mcfarlane, Jennifer Pett-Ridge, Katherine A. Heckman Aug 2015

Radiocarbon Isotopic Classification Of Deep Tropical Forest Soils, Brooke Butler, Karis J. Mcfarlane, Jennifer Pett-Ridge, Katherine A. Heckman

STAR (STEM Teacher and Researcher) Presentations

Tropical forest soils have an important role in global carbon (C) stocks. Small changes in the cycling of C could drastically affect atmospheric carbon dioxide (CO2) concentrations and active cycling of carbon in a forest community. Currently, little is understood of how tropical forest soils will respond to the increasing global temperatures. To examine the effects of warming/ drought on losses of older versus younger soil C pools, we implemented radiocarbon (14C) isotopic characterization of various soil plot samples and depths from the Luquillo Experimental Forest, Puerto Rico. 14C was measured using Accelerated Mass Spectrometry (AMS) from catalytically condensed carbon ...


Sediment Loss Of Santa Rosa Island Slopes: An Erosional Study, Michael Perez Aug 2015

Sediment Loss Of Santa Rosa Island Slopes: An Erosional Study, Michael Perez

STAR (STEM Teacher and Researcher) Presentations

Ranching began on Santa Rosa Island in the 1840’s, consequently introducing nonnative megafauna that put novel selective grazing pressures on endemic plant species. Their movement patterns also altered sediment integrity as the land was denuded of any stabilizing vegetation. Dense groves of island oak (Q. tomentella) are known to aid in sediment deposition and retention. The groves also function to collect water during periods of intense fog that are common to the island. This experiment sought to quantify the volume of sediment that has been lost on a south facing slope in the middle of the island that contains ...


The Pioneer Of Santa Rosa Island, Andrea Martinez, Michael Perez, Kathryn Mceachern, Sarah Chaney, Ken Niessen Jul 2015

The Pioneer Of Santa Rosa Island, Andrea Martinez, Michael Perez, Kathryn Mceachern, Sarah Chaney, Ken Niessen

STAR (STEM Teacher and Researcher) Presentations

Santa Rosa Island which is part of the Channel Islands in California has a ranching history that goes as far back as the year 1843. While rich in history, the island is no longer “rich” in native plant populations due to the sheep, cattle and other livestock that once occupied the island. As a result of these grazers that the ranchers livelihood depended on, a great disturbance in the native plant population took place. It is up to plants such as Baccharis pilularis, commonly known as Coyote brush, to assist these endangered and threatened plants to once again flourish on ...


Estimating Migration Rates Between Populations Of Zostera Marina In The San Francisco Bay, Elizabeth S. Gutierrez Sep 2014

Estimating Migration Rates Between Populations Of Zostera Marina In The San Francisco Bay, Elizabeth S. Gutierrez

STAR (STEM Teacher and Researcher) Presentations

Eelgrass (Zostera marina) is a highly clonal marine angiosperm that can also reproduce sexually through flowering and seed formation. In a previous study, Fst values from six microsatellite loci suggested that a perennial San Francisco Bay subpopulation at Point Molate (Richmond, California) was able to recover from a drastic 2006 die-off through seed recruitment from neighboring eelgrass subpopulations, changing its reproductive strategy from clonal to sexual. Although Fst measures continue to be widely used in population genetics, the assumptions under which they operate are not always appropriate given certain circumstances, such small population sizes and/or asymmetrical migration rates. Our ...


Leatherback Hatchling Fitness, Violet Campbell, Shane Morales, Kelly Stewart Aug 2013

Leatherback Hatchling Fitness, Violet Campbell, Shane Morales, Kelly Stewart

STAR (STEM Teacher and Researcher) Presentations

Leatherback hatchling fitness on land is essential for their success in entering the ocean without being predated. Two ways fitness on land may be measured are by how fast hatchlings crawl as well as how fast their righting responses are when they are flipped onto their carapaces. Hatchlings from certain nests have slower righting response times along with slower crawl times, both of which would increase the odds of predation and hinder the success of hatchlings reaching the ocean.

Hatchling crawling speed was determined by timing 12 randomly selected hatchlings from each nest to crawl a distance of two meters ...


Developing Monitoring Methods For Leptasterias Spp. As Sentinel Species In Detecting Local Environmental Changes, Zachary Sturbaum, Kathryn Nuessly, Riley J. Smith, C. Sarah Cohen Aug 2012

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 (STEM Teacher and Researcher) 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. as sentinel ...


A Genetic Survey Of English Sole Populations In The Salish Sea, Elizabeth S. Gutierrez, Gary A. Winans, Jon Baker, Amanda Cope Aug 2012

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

STAR (STEM Teacher and Researcher) 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 ...


Using Stable Isotope Analysis To Study Zooplankton Trophic Ecology In San Francisco Estuary, Steven C. Westbrook, Julien Moderan, Wim Kimmerer Aug 2012

Using Stable Isotope Analysis To Study Zooplankton Trophic Ecology In San Francisco Estuary, Steven C. Westbrook, Julien Moderan, Wim Kimmerer

STAR (STEM Teacher and Researcher) Presentations

Zooplankton biomasses in estuaries are often high and represent an important food source for fish, like theendangered Delta Smelt. Human interferences (nitrates from crops, freshwater 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. Every living thing has a specific isotopic signature. For example, in the plankton we study exists Carbon 13 and Carbon 12. Carbon 13 is different only because it has one extra neutron ...


Effects Of Pristane On Growth Of Pink Salmon (Oncorhynchus Gorbuscha), Brielle D. Kemis, Bonita Nelson Aug 2012

Effects Of Pristane On Growth Of Pink Salmon (Oncorhynchus Gorbuscha), Brielle D. Kemis, Bonita Nelson

STAR (STEM Teacher and Researcher) Presentations

Pristane is a naturally occurring hydrocarbon that is generated by copepods in marine ecosystems. Organisms that eat copepods do not readily metabolize pristane, which causes it to accumulate throughout the marine food web. Understanding how pristane affects marine fish is essential because pristane is often used as a bioindicator in lab studies and may be influencing results in those studies. Also, this hydrocarbon may significantly reduce growth of marine fish in the wild. A previous study indicated that pristane is an appetite suppressant and growth retardant in fish. However, the study implemented a feeding regime with unnaturally high levels of ...