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Full-Text Articles in Life Sciences
Peruvian Pinnipeds As Archivists Of Enso Effects, Mickie Rae Edwards
Peruvian Pinnipeds As Archivists Of Enso Effects, Mickie Rae Edwards
HCNSO Student Theses and Dissertations
Environmental fluctuations in the eastern Pacific Ocean are reflected in the tissues of some of its most vulnerable apex predators, the Peruvian fur seal (PFS) Arctocephalus australis ssp.and the South American sea lion (SASL) Otaria byronia.These large pinnipeds live in sympatry along the Pacific coastline of South America and forage within the neritic waters over the continental shelf. The coastal waters off Peru are a region of great environmental fluctuations due to periodic, oscillating El Niño- La Niña- Southern Oscillation (ENSO) events, which result in ecosystem-wide food web changes. Pinniped vibrissae (whiskers) are continuously growing keratinous tissues and …
Evidence Of Intermittent Residency In The Northern Fur Seal (Callorhinus Ursinus)., Megan Foley
Evidence Of Intermittent Residency In The Northern Fur Seal (Callorhinus Ursinus)., Megan Foley
HCNSO Student Theses and Dissertations
This study found evidence of intermittent, multi-year residency periods in northern fur seals (Callorhinus ursinus) using stable isotope ratios in vibrissae and canine teeth. Northern fur seals migrate from the Bering Sea during summer months to lower latitudes and slightly warmer waters of the northeastern Pacific Ocean and California Current in the winter. To determine the length of time spent away from the Bering Sea, growth rate was estimated using the covarying oscillations δ13C and δ15N, estimated to be 0.09 mm/day. The δ13C and δ15N in vibrissae from 30 male …
Trophic Ecology Of Green Turtles (Chelonia Mydas) From Dry Tortugas National Park, Florida, David C. Roche
Trophic Ecology Of Green Turtles (Chelonia Mydas) From Dry Tortugas National Park, Florida, David C. Roche
HCNSO Student Theses and Dissertations
Located 100 km west of Key West, Florida, Dry Tortugas National Park (DRTO) is a largely untouched subtropical marine ecosystem that serves as an important developmental habitat, nesting ground, and foraging area for several species of sea turtles, including green turtles. The Park supports a recovering population of green turtles comprised of resident juveniles, subadults, and adults of both sexes; nesting females include residents and migrating females that only return to nest. Stable isotope analysis has been applied widely to describe the trophic ecology of green turtles, from urbanized bays with significant anthropogenic input, to relatively pristine ecosystems with healthy …
Biological And Physical Analysis Of Currents And Water Masses Off The Coast Of Southeast Florida, Stephanie Healey
Biological And Physical Analysis Of Currents And Water Masses Off The Coast Of Southeast Florida, Stephanie Healey
HCNSO Student Theses and Dissertations
Biological and physical sampling of a 10km long, east-west transect was performed during 2007, off the coast of southeast Florida. Temperature and salinity measurements were recorded using a conductivity-temperature-depth (CTD) sensor, and current direction and magnitude measurements were recorded using an acoustic Doppler current profiler (ADCP). Zooplankton samples were collected, during the daytime, using a Tucker multiple net mid-water trawl, with 760μm mesh, at intended depths of ~25m and ~200m, at three stations along the transect. Laboratory analysis indicated that several currents and water masses influenced the density distribution of calanoid copepods and chaetognaths. During April and September 2007, a …