Search results | Digital Commons of Moss Landing Marine Laboratories

Title: Exploring the davidson seamount: Combining science, public outreach, and resource management,
Description: Scientific information is often interpreted to the public long after it has been discovered. NOAA programs and private organizations are interested in more immediate sharing of information with the public so that it can be more effectively used in resource management. The Davidson Seamount is an underwater volcano off the coast of Central California, and recent advances in technology provide the opportunity to explore and characterize the biology of this deep-sea habitat. With an interdisciplinary team of scientists, outreach specialists, and resource managers, this exploration was presented to the public as it was happening with daily updates on a web site. The public also interacted by e-mail with the explorers during the expedition. Huge corals and sponges, deep-water fishes, and the technology needed to study this deep, dark habitat particularly engaged the public, resource managers, and scientists alike. Following the cruise there was national media interest in discoveries from the expedition, not only because the findings were spectacular, but because significant efforts were made to provide the media with access to the explorers and images of the findings. Resource managers are already using summary information from the cruise in processes that may potentially protect Davidson Seamount habitats. Even before the scientific data has been completely analyzed, the public and resource managers have been engaged in a healthy process of information sharing. In characterizing the biology of Davidson Seamount, we found that this model of an interdisciplinary expedition effectively integrated new scientific information into public understanding and management options for a unique area., , ,
Author: DeVogelaere, Kochevar, Tamburri, Cailliet, Burton, Benson, Douros
Date: 2005-01-01T00:00:00Z

Title: Radiometric age validation of Atlantic tarpon, Megalops atlanticus,
Description: An improved radiometric aging technique was used to examine annulus-derived age estimates from otoliths of the Atlantic tarpon, Megalops atlanticus. Whole otoliths from juvenile fish and otolith cores, representing the first 2 years of growth, from adult fish were used to determine 210Pb and 226Ra activity; six age groups consisting of pooled otoliths and nine individual otolith cores were aged. This unprecedented use of individual otolith cores to determine age was possible because of improvements made to the 226Ra determination technique. The disequilibria of 210Pb:226Ra for these samples were used to determine radiometric age. Annulus-derived age estimates did not agree closely with radiometric age determinations. In most cases, the precision (CV≤12%) among the otolith readings could not explain the differences. The greatest radiometric age was 78.0 yr for a 2045-mm-FL female, where the radiometric error encompassed the annulus-derived age estimate of 55 yr by about 4 yr. The greatest radiometric age for males was 41.0 yr for a 1588-mm-FL tarpon, where the radiometric error encompassed the annulus-derived age estimate of 32 yr by 1 yr. Radiometric age determinations in this study indicated that the interpretation of growth zones in Atlantic tarpon otoliths can be difficult, and in some cases may be inaccurate. This study provides conclusive evidence that the longevity of the Atlantic tarpon is greater than 30 years for males and greater than 50 years for females., Cited By (since 1996):9, CODEN: FSYBA, ,
Author: Andrews, Burton, Coale, Cailliet, Crabtree
Date: 2001-01-01T00:00:00Z

Title: Application of an ion-exchange separation technique and thermal ionization mass spectrometry to 226Ra for radiometric age determination of long-lived fishes,
Description: Cited By (since 1996):31, , , ,
Author: Andrews, Coale, Nowicki, Lundstrom, Palacz, Burton, Cailliet
Date: 1999-01-01T00:00:00Z

Title: Radiometric age validation of Atlantic tarpon, Megalops atlanticus,
Description: Cited By (since 1996):10, , , ,
Author: Andrews, Burton, Coale, Cailliet, Crabtree
Date: 2001-01-01T00:00:00Z

Title: Explorating the Davidson Seamount: combining science, public outreach, and resource management
Author: DeVogelaere, Kochevar, Tamburri, Cailliet, Burton, Benson, Douros, Magoon, Converse, Baird, Jines, Miller-Henson
Date: 2005-01-01T00:00:00Z

Title: Bomb radiocarbon and lead-radium disequilibria in otoliths of bocaccio rockfish (Sebastes paucispinis),
Description: Longevity estimates for the bocaccio rockfish (Sebastes paucispinis) using traditional techniques range from less than 20 years to approximately 50 years. Otoliths of bocaccio are difficult to age, and previous attempts to validate ages have been unsuccessful. Because otolith age suggests the bocaccio are reasonably long-lived, lead-radium dating was used in an attempt to independently age bocaccio otoliths. The measured 210Pb and 226Ra activities were among the lowest reported and resulted in poor radiometric age resolution; however, the break-and-burn technique clearly underestimated age in some cases with the longevity of the bocaccio being at least 31 years. To provide better age resolution, the bomb radiocarbon approach was applied to individual otoliths. Based on measured radiocarbon levels relative to a reference time-series, several specimens were aged at approximately 30-40 years. To evaluate these determinations, the remaining otolith of the pair was sectioned and aged blind. The result was an excellent fit to the reference time-series and a validation of the age estimates. The maximum age from growth zone counts was 37 ± 2 years, which is consistent with a reported maximum age of approximately 50 years. © CSIRO 2005., Cited By (since 1996):18, Fish and Fisheries, CODEN: AJMFA, ,
Author: Andrews, Burton, Kerr, Cailliet, Coale, Lundstrom, Brown
Date: 2005-01-01T00:00:00Z

Title: Age determination and validation studies of marine fishes,
Description: Age determination and validation studies on deep-water marine fishes indicate they are difficult to age and often long-lived. Techniques for the determination of age in individual fish includes growth-zone analysis of vertebral centra, fin rays and spines, other skeletal structures, and otoliths (there are three sets of otoliths in most bony fish semicircular canals, each of which is made of calcium carbonate). Most have regular increments deposited as the fish (and its semicircular canals) grows. The most commonly used otolith for age determination is the largest one called the sagitta. Age validation techniques include: (1) tag-recapture, often combined with oxytetracycline injection and analysis in growth-zones of bone upon recapture; (2) analysis of growth-zones over time; and (3) radiometric approaches utilizing a known radioactive decay series as an independent chronometer in otoliths from bony fishes. We briefly summarize previous studies using these three validation approaches and present results from several of our radiometric studies on deep-water, bony fishes recently subjected to expanding fisheries. Radiometric age validation results are presented for four species of scorpaenid fishes (the bank, Sebastes rufus, and bocaccio, S. paucispinis, rockfishes, and two thornyhead species, Sebastolobus altivelis and S. alascanus). In addition, our analysis of scorpaenids indicates that longevity increases exponentially with maximum depth of occurrence. The reason that the deep-water forms of scorpaenid fishes are long-lived is uncertain. Their longevity, however, may be related to altered physiological processes relative to environmental parameters like low temperature, high pressures, low light levels, low oxygen, and poor food resources. Copyright © 2001 Elsevier Science Inc., Cited By (since 1996):102, Fish and Fisheries, CODEN: EXGEA, ,
Author: Cailliet, Andrews, Burton, Watters, Kline, Ferry-Graham
Date: 2001-01-01T00:00:00Z

Title: Bomb radiocarbon and lead-radium disequilibria in otoliths of bocaccio rockfish (Sebastes paucispinis): A determination of age and longevity for a difficult-to-age fish,
Description: , , , ,
Author: Andrews, Burton, Kerr, Cailliet, Coale, Lundstrom, Brown

Title: Application of radiometric age determination to three long-lived fishes using 210Pb:226Ra disequilibria in calcified structures: A review
Author: Burton, Andrews, Coale, Cailliet, Musick
Date: 1999-01-01T00:00:00Z

Title: Application of an ion-exchange separation technique and thermal ionization mass spectrometry to 226Ra for radiometric age determination of long-lived fishes,
Description: To improve the accuracy and precision of radiometric age determination using 210Pb: 226Ra disequilibria in otoliths of fishes, a technique was developed incorporating an ion-exchange procedure followed by isotope-dilution thermal ionization mass spectrometry (TIMS) to determine 226Ra. This technique counts ionized radium atoms directly; therefore, the uncertainty of the technique is superior to conventional radio-decay dependent techniques. Calcium and barium are major components of the otolith matrix that can interfere with TIMS analysis of radium. To remove these interferants, an ion-exchange separation procedure was developed. This procedure was tested by applying it to otolith samples from three fish species in three separate radiometric ageing studies. The resultant separations and TIMS determinations indicate that the procedure efficiently separates radium from calcium and barium. Measured 226Ra activities for each species were similar to previous radiometric ageing studies, with the exception of one sample. When results were compared with traditional 226Ra determination techniques, radon emanation and α-spectrometry, the separation procedure with isotope-dilution TIMS had significant advantages. Samples over three times smaller than attempted in other studies were processed with decreased uncertainty and processing time., Cited By (since 1996):30, Fish and Fisheries, CODEN: CJFSD, ,
Author: Andrews, Coale, Nowicki, Lundstrom, Palacz, Burton, Cailliet
Date: 1999-01-01T00:00:00Z