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Terrestrial and Aquatic Ecology Commons

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Full-Text Articles in Terrestrial and Aquatic Ecology

Zooplankton Trophic Ecology In The San Francisco Estuary During Summer As Determined By Stable Isotope Analysis, Kyla Bradylong, Steven Westbrook, Julien Moderan, Wim Kimmerer Aug 2013

Zooplankton Trophic Ecology In The San Francisco Estuary During Summer As Determined By Stable Isotope Analysis, Kyla Bradylong, Steven Westbrook, Julien Moderan, Wim Kimmerer

STAR Program Research Presentations

Declines in the abundance of several pelagic fish species in the upper San Francisco Estuary have prompted investigation into food web interactions within the estuary and delta (the lower Sacramento and San Joaquin Rivers). This area is characterized by low primary production and pelagic food webs much longer and reticulated than previously thought, implying low efficiency in the energy transfers from primary producers to planktivorous fish. We determined the carbon and nitrogen stable isotope (SI) composition of zooplankton samples collected monthly between June 2012 and February 2013 at eight stations along the salinity gradient. As consumers SI composition reflects that …


Jellyfish Identification And Quantification In The San Francisco Estuary, Amalia Borson, Lindsay L. Sullivan, Wim Kimmerer Aug 2013

Jellyfish Identification And Quantification In The San Francisco Estuary, Amalia Borson, Lindsay L. Sullivan, Wim Kimmerer

STAR Program Research Presentations

As potential predators and competitors of plankton-eating fish, jellyfish have the potential to negatively impact fish populations. Jellyfish were collected weekly with plankton tows from the RombergTiburonCenterpier in Tiburon, CA. Since some jellyfish were too small to identify, one tow was collected and preserved to record abundances, and a second tow was collected to rear jellyfish until distinguishing characteristics were visible enough for identification. Jellyfish in the preserved tows were then identified, measured, and counted, and their abundance (number m-3) was calculated. Jellyfish from the second tows were reared in plastic buckets that were lightly bubbled using aquarium …


Feeding Ecology Of Delta Smelt During A Seasonal Pulse Of Turbidity, William A. Hilton, Aaron Johnson, Wim Kimmerer Aug 2013

Feeding Ecology Of Delta Smelt During A Seasonal Pulse Of Turbidity, William A. Hilton, Aaron Johnson, Wim Kimmerer

STAR Program Research Presentations

The delta smelt (Hypomesus transpacificus) is a small, pelagic fish endemic to the San Francisco Estuary (SFE) and protected under federal and state endangered species acts. This study examines the diet of adult delta smelt during their spawning migration in the winters of 2010 and 2012. Delta smelt and their zooplankton prey were sampled concurrently during a seasonal pulse of turbidity at sites along their migratory route from the low salinity zone in Suisun Bay to the fresher waters of the Sacramento/San Joaquin Delta. Gut contents were identified to the lowest possible taxon and counted, along with zooplankton …


A Multispecies Avian Abundance Analysis In Riparian And Oak Woodland Habitats On The California Central Coast, Jacy Hyde Mar 2013

A Multispecies Avian Abundance Analysis In Riparian And Oak Woodland Habitats On The California Central Coast, Jacy Hyde

Biological Sciences

I investigated the abundance and diversity of riparian and oak woodland birds in a section of the Los Padres National Forest in Coastal Central California. Point counts were conducted in Oak Woodland and Riparian habitats during the summer of 2012. Point counts were replicated in time (2x) and space (25 replicates). The data were analyzed using Program Distance to correct for differing detection probabilities between species and habitat types. The two habitat types showed no significant difference in species richness. For most species, there was no difference in density between riparian and oak woodland habitats. However, the two species with …