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Full-Text Articles in Life Sciences

What Can We Learn From Confusing Olivella Columellaris And O. Semistriata, Two Key Species In Panamic Sandy Beach Ecosystems?, Alison Troost, Samantha Rupert, Ariel Cyrus, Frank Paladino, Benjamin Dattilo, Winfried Peters Jul 2014

What Can We Learn From Confusing Olivella Columellaris And O. Semistriata, Two Key Species In Panamic Sandy Beach Ecosystems?, Alison Troost, Samantha Rupert, Ariel Cyrus, Frank Paladino, Benjamin Dattilo, Winfried Peters

Benjamin F. Dattilo

Olivella columellaris (Sowerby 1825) and O. semistriata (Gray 1839) are suspension feeding, swash surfing snails on tropical sandy beaches of the east Pacific. While they often are the numerically dominant macrofaunal element in their habitats, their biology is poorly understood; the two species actually have been confused in all of the few publications that address their ecology. Frequent misidentifications in publications and collections contributed also to an overestimation of the geographic overlap of the two species. To provide a sound taxonomic basis for further functional, ecological, and evolutionary investigations, we evaluated the validity of diagnostic traits in wild populations and …


Patterns Of Life History And Habitat Use Of An Important Recreational Fishery Species, Spotfin Croaker, And Their Potential Fishery Implications, Jonathan Williams, Jeremy Claisse, Daniel Pondella, Lea Medeiros, Charles Valle, Michael Shane Nov 2012

Patterns Of Life History And Habitat Use Of An Important Recreational Fishery Species, Spotfin Croaker, And Their Potential Fishery Implications, Jonathan Williams, Jeremy Claisse, Daniel Pondella, Lea Medeiros, Charles Valle, Michael Shane

Daniel Pondella

Spotfin croakers Roncador stearnsii, a prized recreational catch, were collected throughout the Southern California Bight, primarily as bycatch from a long-term, scientific gill-net collection effort. The maximum otolith-based age in the present study was 24 years—14 years greater than in a previous scale-based aging study. Multiple models were used to estimate mean length at age, including models that utilize larvae as well as juveniles and adults, and the model selection results suggest sexual dimorphism in growth patterns. The juvenile and adult catch per unit effort reflected a clear pattern of habitat selectivity, with fish strongly preferring soft-bottom habitats. Catches …


El Niño Periods Increase Growth Of Juvenile White Seabass (Atractoscion Nobilis) In The Southern California Bight, Jonathan Williams, Larry Allen, Mark Steele, Daniel Pondella Nov 2012

El Niño Periods Increase Growth Of Juvenile White Seabass (Atractoscion Nobilis) In The Southern California Bight, Jonathan Williams, Larry Allen, Mark Steele, Daniel Pondella

Daniel Pondella

Studies of the impact of El Niño periods on marine species have usually focused on negative, highly visible eVects, e.g., decreasing growth rates or increasing mortality due to a decline in primary productivity in typically nutrient rich upwelling zones; but positive effects related to elevated water temperature are also known. This study examined how the growth rate of juvenile white seabass, Atractoscion nobilis, responded to changes in ocean temperature in an El Niño period (1997–1998) in the northern portion of the Southern California Bight, USA. Growth rates of juvenile white seabass during their first 4 years of life were …


Life History, Ecology, And Long-Term Demographics Of Queenfish, Eric Miller, Jonathan Williams, Daniel Pondella, Kevin Herbinson Nov 2012

Life History, Ecology, And Long-Term Demographics Of Queenfish, Eric Miller, Jonathan Williams, Daniel Pondella, Kevin Herbinson

Daniel Pondella

Queenfish Seriphus politus were collected at coastal power plants from San Clemente to Ventura, California. Power functions best described relations between otolith length, width, or weight and either standard length (SL) or total body weight. The length–weight relationship was described by the following equation: weight 1⁄4 10􏰀5 3 SL3.09. Individuals were aged to 12 years by using sagittal otolith sections. Females grew at a significantly faster rate than males. Both sexes reached 50% maturity by 100 mm SL, or shortly after age 1. The total annual instantaneous mortality coefficient was estimated at 0.42. Catalina Harbor (on the windward side of …


Ecomorphology Of Plesiosaur Flipper Geometry, F. O’Keefe Sep 2012

Ecomorphology Of Plesiosaur Flipper Geometry, F. O’Keefe

F. Robin O’Keefe

The Plesiosauria is an extinct group of marine reptiles once common in mesozoic seas. Previous work on plesiosaur hunting styles has suggested that short-necked, large-headed animals were pursuit predators, whereas long-necked, small-headed animals were ambush predators. This study presents new data on the aspect ratios (ARs) of plesiosaur flippers, and interprets these data via comparison with AR in birds, bats and aircraft. Performance trade-offs implicit in AR variation are well-understood in the context of aircraft design, and these trade-offs have direct ecomorphological analogues in birds and bats. Knowledge of these trade-offs allows interpretation of variation in plesiosaur AR. By analogy, …


What Can We Learn From Confusing Olivella Columellaris And O. Semistriata, Two Key Species In Panamic Sandy Beach Ecosystems?, Alison Troost, Samantha Rupert, Ariel Cyrus, Frank Paladino, Benjamin Dattilo, Winfried Peters Jun 2012

What Can We Learn From Confusing Olivella Columellaris And O. Semistriata, Two Key Species In Panamic Sandy Beach Ecosystems?, Alison Troost, Samantha Rupert, Ariel Cyrus, Frank Paladino, Benjamin Dattilo, Winfried Peters

Winfried S. Peters

Olivella columellaris (Sowerby 1825) and O. semistriata (Gray 1839) are suspension feeding, swash surfing snails on tropical sandy beaches of the east Pacific. While they often are the numerically dominant macrofaunal element in their habitats, their biology is poorly understood; the two species actually have been confused in all of the few publications that address their ecology. Frequent misidentifications in publications and collections contributed also to an overestimation of the geographic overlap of the two species. To provide a sound taxonomic basis for further functional, ecological, and evolutionary investigations, we evaluated the validity of diagnostic traits in wild populations and …


Enumeration Of Sandy Sediment Bacteria: Search For Optimal Protocol, Slava Epstein, Jeffrey Rossel May 2012

Enumeration Of Sandy Sediment Bacteria: Search For Optimal Protocol, Slava Epstein, Jeffrey Rossel

Slava Epstein

We examined and compared a variety of existing protocols for enumeration of bacteria from marine sandy sediments. The focus was on how to dislodge bacteria from sediment particles; a commercial blender, an ultrasonic cleaner, and an ultrasonic cell disrupter were tested. The ultrasonic cell disrupter was found to be the most efficient device for bacterial dislodgment. With a 5 mm microtip vibrating at 109 μm amplitude and 20 kHz, the optimal sonication time of small (≤ 0.5 cm³) samples was 180 s. Having identified the optimal dislodgment treatment, we went through other steps of sediment bacteria enumeration (use of surfactants, …


Comparing Volunteer And Professionally Collected Monitoring Data From The Rocky Subtidal Reefs Of Southern California, Usa, David Gillett, Daniel Pondella, Jan Freiwald, Kenneth Schiff, Jennifer Caselle, Craig Shuman, Stephen Weisberg Apr 2012

Comparing Volunteer And Professionally Collected Monitoring Data From The Rocky Subtidal Reefs Of Southern California, Usa, David Gillett, Daniel Pondella, Jan Freiwald, Kenneth Schiff, Jennifer Caselle, Craig Shuman, Stephen Weisberg

Daniel Pondella

Volunteer-based citizen monitoring has increasingly become part of the natural resources monitoring framework, but it is often unclear whether the data quality from these programs is sufficient for integration with traditional efforts conducted by professional scientists. At present, the biological and physical characteristics of California’s rocky reef kelp forests are concurrently monitored by two such groups, using similar methodologies—underwater visual census (UVC) of fish, benthic invertebrates, and reef habitat, though the volunteer group limits their sampling to transects close to the reef surface and they use a more constrained list of species for enumeration and measurement. Here, we compared the …


The Behavioural And Sensory Ecology Of Agaronia Propatula (Caenogastropoda, Olividae), A Swash-Surfing Predator On Sandy Beaches Of The Panamic Faunal Province, Ariel Cyrus, Samantha Rupert, Amy Silva, Monika Graf, Jeremy Rappaport, Frank Paladino, Winfried Peters Mar 2012

The Behavioural And Sensory Ecology Of Agaronia Propatula (Caenogastropoda, Olividae), A Swash-Surfing Predator On Sandy Beaches Of The Panamic Faunal Province, Ariel Cyrus, Samantha Rupert, Amy Silva, Monika Graf, Jeremy Rappaport, Frank Paladino, Winfried Peters

Winfried S. Peters

The genus Agaronia includes dominant predators in the eulittoral zone of dissipative sandy beaches of the tropical Eastern Pacific, which show specific adaptations to this environment such as swash-surfing locomotion. We studied A. propatula in its natural habitat in El Salvador and Costa Rica, and performed field experiments to obtain insights into its ecology, behaviour and sensory physiology. Agaronia propatula is not attracted by carrion and preys mostly on the ubiquitous beach snail Olivella semistriata. This, however, reflects community composition rather than prey specialization; A. propatula is an investigative hunter and will, quite literally, attack everything that moves (with …


Sharks Of The Devonian, Andrew Blitman Dec 2011

Sharks Of The Devonian, Andrew Blitman

Andrew Blitman

No abstract provided.


Reeling You In: Billfish In Popular Culture, Andrew Blitman Dec 2011

Reeling You In: Billfish In Popular Culture, Andrew Blitman

Andrew Blitman

No abstract provided.