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Title: The feasibility of bomb radiocarbon analysis to support an age-at-length relationship for red abalone, Haliotis rufescens swainson in northern California,
Description: Cited By (since 1996):2, Downloaded from: www.bioone.org/doi/pdf/10.2983/0730-8000-27.5.1177 (3 July 2014)., , , ,
Author: Leaf, Andrews, Cailliet, Brown
Date: 2008-01-01T00:00:00Z

Title: Age estimation and lead-radium dating of Antarctic toothfish (Dissostichus mawsoni) in the Ross Sea,
Description: Cited By (since 1996):5, , , ,
Author: Brooks, Andrews, Ashford, Ramanna, Jones, Lundstrom, Cailliet
Date: 2011-01-01T00:00:00Z

Title: Radiometric validation of age, growth, and longevity for the blackgill rockfish (Sebastes melanostomus),
Description: As nearshore fish populations decline, many commercial fishermen have shifted fishing effort to deeper continental slope habitats to target fishes for which biological information is limited. One such fishery that developed in the northeastern Pacific Ocean in the early 1980s was for the blackgill rockfish (Sebastes melanostomus), a deep-dwelling (300-800 m) species that congregates over rocky pinnacles, mainly from southern California to southern Oregon. Growth zone-derived age estimates from otolith thin sections were compared to ages obtained from the radioactive disequilibria of 210Pb, in relation to its parent, 226Ra, in otolith cores of blackgill rockfish. Age estimates were validated up to 41 years, and a strong pattern of agreement supported a longevity exceeding 90 years. Age and length data fitted to the von Bertalanffy growth function indicated that blackgill rockfish are slow-growing (& = 0.040 females, 0.068 males) and that females grow slower than males, but reach a greater length. Age at 50% maturity, derived from previously published length-atmaturity estimates, was 17 years for males and 21 years for females. The results of this study agree with general life history traits already recognized for many Sebastes species, such as long life, slow growth, and late age at maturation. These traits may undermine the sustainability of blackgill rockfish populations when heavy fishing pressure, such as that which occurred in the 1980s, is applied., Cited By (since 1996):13, CODEN: FSYBA, ,
Author: Stevens, Andrews, Cailliet, Coale, Lundstrom
Date: 2004-01-01T00:00:00Z

Title: Growth rate and age determination of bamboo corals from the northeastern Pacific Ocean using refined 210Pb dating,
Description: Bamboo corals from Davidson Seamount and from the Gulf of Alaska were aged using a refined 210Pb dating technique. The goal was to determine growth rates and age for several bamboo corals with higher precision. Radiometric results for 2 Davidson Seamount corals (Keratoisis sp.) converged on a radial growth rate of ∼0.055 mm yr-1. One colony was aged at 98 ± 9 yr, with an average axial growth rate of ∼0.7 cm yr -1. The age of a large colony was >145 yr with an estimated axial growth rate of 0.14 to 0.28 cm yr-1. Inconsistent rates may indicate nonlinear axial growth. A Keratoisis sp. specimen from the Gulf of Alaska was aged at 116 ± 29 yr from a radial growth rate of ∼0.056 mm yr -1, which led to an average axial growth rate of ∼1.0 cm yr -1. An Isidella tentaculum colony was aged at 53 ± 10 yr and grew most rapidly with a radial growth rate of ∼0.10 mm yr-1 and an average axial growth rate of ∼1.4 cm yr-1; however, the 210Pb decay pattern may have provided evidence for either a hiatus in radial growth or environmental changes in 210Pb. Our findings of slow growth and long life compared favorably with other bamboo coral studies and provided age estimates with greater precision. The high longevity of bamboo coral is an indication that recovery from disturbance or removal may take decades to a century. These age data provide a basis for a defensible position on the protection of bamboo coral and essential information for describing other life history characteristics., Cited By (since 1996):12, CODEN: MESED, ,
Author: Andrews, Stone, Lundstrom, Devogelaere
Date: 2009-01-01T00:00:00Z

Title: Age and growth of the pacific grenadier (Coryphaenoides acrolepis) with age estimate validation using an improved radiometric ageing technique,
Description: Current and historic longevity estimates for the Pacific grenadier (Coryphaenoides acrolepis) range from 6 to greater than 60 years. Age estimates in this study using growth increment counts in thin otolith sections indicate the Pacific grenadier is a long-lived fish. To validate this growth information, age was determined using the radioactive disequilibria of 210Pb and 226Ra in otolith cores from adult Pacific grenadier. Radiometric ages closely agreed with age estimates from counting growth increments, which confirms their annual periodicity. Radiometric results indicate the Pacific grenadier can live at least 55.8 years (-7.4, +10.1 years). Growth increment counts from large fish indicate longevity may approach 73 years. Because the Pacific grenadier is long-lived and matures late in life, it may be vulnerable to heavy fishing pressure. Therefore, conservation measures need to be taken to sustain this rapidly developing fishery., Cited By (since 1996):39, Fish and Fisheries, CODEN: CJFSD, ,
Author: Andrews, Cailliet, Coale
Date: 1999-01-01T00:00:00Z

Title: Fish faunal and habitat analyses using trawls, camera sleds and submersibles in benthic deep-sea habitats off central California,
Description: Beam trawl, camera sled and submersible data from 2 000-3 300 m off central California produced similar fish faunal composition, but different density estimates. All species caught in trawls were observed in camera-sled and submersible observations. However, some rare species that were observed were not caught in trawls. The fish fauna was dominated by the families Macrouridae, Zoarcidae, Moridae, and Rajidae. Fishes both trawled and observed were the macrourids Coryphaenoides armatus, C. filifer and C. leptolepis; the zoarcids Bothrocara spp., Pachycara lepinium and Lycenchelys spp.; the morid Antimora microlepis; the rajid Bathyraja trachura, the ophidiid Spectrunculus grandis, and the liparidid Careproctus ovigerum. One unidentified liparidid (Paraliparis sp.) and two unidentified Lycenchelys spp. were trawled and may have been seen but also could not be identified to species from photographs. Observed only in photographs were the liparidids Paraliparis rosaceus and Careproctus melanurus, synodontid Bathysaurus mollis, and notocanthid Notacanthus chemnitzii. These three techniques differed in their ability to provide specimens for accurate identification, counts, and later life history (feeding habit, age and growth, and reproduction) studies, and to provide information on dispersion, habitat utilization, behavior and interactions. Accurate density estimates were undoubtedly hampered by trawl and camera sled avoidance, escape, and uncertainties concerning the area trawled. Camera sleds produced higher (and perhaps better) estimates of density. Submersible observations from the DSV Alvin produced a similar species list but little additional, quantitative information. Both visual techniques allowed habitat characterization, but no strong faunal associations with habitat types were observed., Cited By (since 1996):29, CODEN: OCACD, ,
Author: Cailliet, Andrews, Wakefield, Moreno, Rhodes
Date: 1999-01-01T00:00:00Z

Title: Age validation of quillback rockfish (Sebastes maliger) using bomb radiocarbon,
Description: Rockfishes (Sebastes spp.) support one of the most economically important fisheries of the Pacific Northwest and it is essential for sustainable management that age estimation procedures be validated for these species. Atmospheric testing of thermonuclear devices during the 1950s and 1960s created a global radiocarbon (14C) signal in the ocean environment that scientists have identified as a useful tracer and chronological marker in natural systems. In this study, we first demonstrated that fewer samples are necessary for age validation using the bomb-generated 14C signal by emphasizing the utility of the time-specific marker created by the initial rise of bomb-14C. Second, the bomb-generated 14C signal retained in fish otoliths was used to validate the age and age estimation method of the quillback rockfish (Sebastes maliger) in the waters of southeast Alaska. Radiocarbon values from the first year's growth of quillback rockfish otoliths were plotted against estimated birth year to produce a 14C time series spanning 1950 to 1985. The initial rise in bomb-14C from prebomb levels (∼ -90‰) occurred in 1959 [±1 year] and 14C levels rose relatively rapidly to peak Δ14C values in 1967 (+105.4‰) and subsequently declined through the end of the time series in 1985 (+15.4‰). The agreement between the year of initial rise of 14C levels from the quillback rockfish time series and the chronology determined for the waters of southeast Alaska from yelloweye rockfish (S. ruberrimus) otoliths validated the aging method for the quillback rockfish. The concordance of the entire quillback rockfish 14C time series with the yelloweye rockfish time series demonstrated the effectiveness of this age validation technique, confirmed the longevity of the quillback rockfish up to a minimum of 43 years, and strongly confirms higher age estimates of up to 90 years., Cited By (since 1996):22, Fish and Fisheries, CODEN: FSYBA, ,
Author: Kerr, Andrews, Munk, Coale, Frantz, Cailliet, Brown
Date: 2005-01-01T00:00:00Z

Title: Assessment of radiometric dating for age validation of deep-water dogfish (Order: Squaliformes) finspines
Description: Vertebrae of most deep-water sharks are too poorly calcified to record visible growth bands and therefore are not useful for age determination. Most dogfish species (Order: Squaliformes) possess dorsal finspines and several recent studies have shown that these structures offer potential for age determination. Age validation should be central to any age determination study, yet to date no age and growth study of deep-water sharks has included a complete validation of age estimates. In this study we sought to age two deep-water dogfish species by analyzing 210Pb and 226Ra incorporated into the internal dentin of the finspines. These radiometric age estimates were compared with counts of internal growth bands observed in the finspines. A pilot study indicated that dorsal finspines of Centroselachus crepidater are too small and thus offer insufficient mass for the radiometric techniques employed in this study. For ageing larger finspines of Centrophorus squamosus, the lead-radium disequilibria method (ingrowth of 210Pb from 226Ra) was found to be inapplicable due to exogenous uptake of 210Pb in the finspine. Therefore, to approximate age, we measured the decay of 210Pb within the dentin material at the tip of the finspine (formed in utero), relative to the terminal material at the base of the finspine. Results with this method proved to be inconsistent and did not yield reliable age estimates. Hence the use of 210Pb and 226Ra for radiometric age determination and validation using dorsal finspines from these deep-water dogfishes was deemed unsuccessful. This outcome was likely due to violations of the consistent, life-long isotopic uptake assumption as well as the provision that the finspine must function as a closed system for these radioisotopes. Future improvements in analytical precision will allow for smaller samples to be analyzed, potentially yielding a better understanding of the fate of these radioisotopes within finspine dentin throughout the life of the shark. © 2013 Elsevier B.V., Fish and Fisheries
Author: Cotton, Andrews, Cailliet, Grubbs, Irvine, Musick
Date: 2014-01-01T00:00:00Z

Title: Application of bomb radiocarbon chronologies to shortfin mako (Isurus oxyrinchus) age validation,
Description: Age estimation is an issue for the shortfin mako, Isurus oxyrinchus, because of disagreement on vertebral band-pair deposition periodicity. In the 1950s-1960s, thermonuclear testing released large amounts of radiocarbon into the atmosphere, which diffused into the ocean through gas exchange. This influx created a time-specific marker that can be used in age validation. Annual band-pair deposition in the porbeagle, Lamna nasus, was validated in a previous study and indicated preliminary annual deposition in the shortfin mako, using four samples from one vertebra. In the present study, age estimates from 54 shortfin mako vertebrae collected in 1950-1984 ranged 1-31 years. Ageing error between readers was consistent, with 76% of the estimates ranging within 2 years. Twenty-one Δ14C values from eight shortfin mako vertebrae (collected in the western North Atlantic in 1963-1984) ranged -154.8‰ to 86.8‰. The resulting conformity with the Δ14C timeline for the porbeagle supported annual band-pair deposition in vertebrae of the shortfin mako. © 2006 Springer Science+Business Media, Inc., Cited By (since 1996):19, Fish and Fisheries, CODEN: EBFID, ,
Author: Ardizzone, Cailliet, Natanson, Andrews, Kerr, Brown
Date: 2006-01-01T00:00:00Z

Title: Age validation of canary rockfish (Sebastes pinniger) using two independent otolith techniques,
Description: Canary rockfish (Sebastes pinniger) have long been an important part of recreational and commercial rockfish fishing from south-east Alaska to southern California, but localised stock abundances have declined considerably. Based on age estimates from otoliths and other structures, lifespan estimates vary from ∼20 years to over 80 years. For the purpose of monitoring stocks, age composition is routinely estimated by counting growth zones in otoliths; however, age estimation procedures and lifespan estimates remain largely unvalidated. Typical age validation techniques have limited application for canary rockfish because they are deep-dwelling and may be long-lived. In this study, the unaged otolith of the pair from fish aged at the Department of Fisheries and Oceans Canada was used in one of two age validation techniques: (1) lead-radium dating and (2) bomb radiocarbon (14C) dating. Age estimate accuracy and the validity of age estimation procedures were validated based on the results from each technique. Lead-radium dating proved successful in determining that a minimum estimate of lifespan was 53 years and provided support for age estimation procedures up to ∼50-60 years. These findings were further supported by Δ14C data, which indicated that a minimum estimate of lifespan was 44 ± 3 years. Both techniques validate, to differing degrees, age estimation procedures and provide support for inferring that canary rockfish can live more than 80 years. © CSIRO 2007., Cited By (since 1996):12, Fish and Fisheries, CODEN: AJMFA, ,
Author: Andrews, Kerr, Cailliet, Brown, Lundstrom, Stanley
Date: 2007-01-01T00:00:00Z

Title: Age and growth of two genera of deep-sea bamboo corals (Family Isididae) in New Zealand waters,
Description: We provide a detailed description of growth zone counts at two locations in the skeletal structure of four bamboo coral colonies (Family Isididae, sub-family Keratoisidinae, genera Lepidisis spp. and Keratoisis sp. from New Zealand). Zone counts were made microscopically on skeletal cross-sections of calcareous internodes producing counts of up to 90 for Lepidisis spp. and 160 for Keratoisis sp. Scanning Electron Microscope (SEM) images taken of cross-sections at the junction of the calcareous internode and gorgonin node revealed clear zone resolution and produced counts that were substantially higher (a maximum 490 zones). Lead-210 dating was applied to the skeletal structure of one specimen of Lepidisis sp. to develop an independent estimate of age and growth. Radial micro-sampling of the skeletal carbonate indicated the age of the colony at the largest section (7.4 mm average radius) was 43 yrs old (26-61 yrs 95% CI), with an average radial growth rate of 0.18 mm yr -1 (0.13-0.29 mm yr-1 95% CI). Comparisons between the three age estimates for Lepidisis sp. were made and it was hypothesized that zones observed by light microscope have a bi-annual periodicity and that SEM-observed zones at the nodal juncture may represent an environmental event, such as lunar periodicity. © 2007 Rosenstiel School of Marine and Atmospheric Science of the University of Miami., Cited By (since 1996):25, Invertebrates, CODEN: BMRSA, ,
Author: Tracey, Neil, Marriott, Andrews, Cailliet, Sanchez
Date: 2007-01-01T00:00:00Z

Title: Radiometric age validation of the yelloweye rockfish (Sebastes ruberrimus) from southeastern Alaska,
Description: Cited By (since 1996):23, , , ,
Author: Andrews, Cailliet, Coale, Munk, Mahoney, O'Connell
Date: 2002-01-01T00:00:00Z

Title: Radiometric validation of age, growth, and longevity for the blackgill rockfish (Sebastes melanostomus),
Description: Cited By (since 1996):13, , , ,
Author: Stevens, Andrews, Cailliet, Coale, Lundstrom
Date: 2004-01-01T00:00:00Z

Title: Age, growth and radiometric age validation of a deep-sea, habitat-forming gorgonian (Primnoa resedaeformis) from the Gulf of Alaska,
Description: Sustainable fisheries require (1) viable stock populations with appropriate harvest limits and (2) appropriate habitat for fish to survive, forage, seek refuge, grow and reproduce. Some deep-water habitats, such as those formed by deep-water stands of coral, may be vulnerable to fishing disturbance. The rate at which habitat can be restored is a critical aspect of fishery management. The purpose of this study was to characterize growth rates for a habitat-forming deep-sea coral. Two nearly complete colonies of red tree coral (Primnoa resedaeformis) collected from waters off southeast Alaska were used for an analysis of age and growth characteristics. CAT scans revealed that colonies consisted of multiple settlement events, where older basal structures provided for settlement of new colonies. The decay of 210Pb over the length of the colony was used to validate age estimates from growth ring counts. Age estimates were over 100 yr for sections near the heavily calcified base. Based on validated growth ring counts, growth of red tree coral ranged from 1.60 to 2.32 cm per year in height and was approximately 0.36 mm per year in diameter. These growth rates suggest that the fishery habitat created by red tree coral is extremely vulnerable to bottom fishing activities and may take over 100 years to recover., Cited By (since 1996):69, Fish and Fisheries, CODEN: HYDRB, ,
Author: Andrews, Cordes, Mahoney, Munk, Coale, Cailliet, Heifetz
Date: 2002-01-01T00:00:00Z

Title: Bomb radiocarbon dating of the endangered white abalone (Haliotis sorenseni): Investigations of age, growth and lifespan
Description: Understanding basic life-history characteristics of white abalone (Haliotis sorenseni), such as estimated lifespan, is critical to making informed decisions regarding the recovery of this endangered species. All predictive modelling tools used to forecast the status and health of populations following restoration activities depend on a validated estimate of adult lifespan. Of the seven Haliotis species in California, white abalone is considered to have the highest extinction risk and was the first marine invertebrate listed as an endangered species under the Federal Endangered Species Act (ESA). Lifespan was previously estimated from observations of early growth; however, no study has generated ages for the largest white abalone. To address questions of age and growth, bomb radiocarbon (Δ14C) dating was used on shells from large white abalone. Measured bomb Δ14C levels were compared to regional Δ14C reference records to provide estimates of age, growth and lifespan. Bomb radiocarbon dating indicated that growth was variable among individuals, with a maximum estimated age of 27 years. The findings presented here provide support for previous age and growth estimates and an estimated lifespan near 30 years. These age data support the perception of a critical need for restoring the remnant aging and potentially senescent population. © CSIRO 2013., Fish & Fisheries, CODEN: AJMFA
Author: Andrews, Leaf, Rogers-Bennett, Neuman, Hawk, Cailliet
Date: 2013-01-01T00:00:00Z

Title: Using x-ray microscopy and Hg L3 XANES to study Hg binding in the rhizosphere of spartina cordgrass,
Description: San Francisco Bay has been contaminated historically by mercury from mine tailings as well as contemporary industrial sources. Native Spartina foliosa and non-native S. alterniflora-hybrid cordgrasses are dominant florae within the SF Bay estuary environment. Understanding mercury uptake and transformations in these plants will help to characterize the significance of their roles in mercury biogeochemical cycling in the estuarine environment. Methylated mercury can be biomagnified up the food web, resulting in levels in sport fish up to 1 million times greater than in surrounding waters and resulting in advisories to limit fish intake. Understanding the uptake and methylation of mercury in the plant rhizosphere can yield insight into ways to manage mercury contamination. The transmission X-ray microscope on beamline 6-2 at the Stanford Synchrotron Radiation Lightsource (SSRL) was used to obtain absorption contrast images and 3D tomography of Spartina foliosa roots that were exposed to 1 ppm Hg (as HgCl2) hydroponically for 1 week. Absorption contrast images of micrometer-sized roots from S. foliosa revealed dark particles, and dark channels within the root, due to Hg absorption. 3D tomography showed that the particles are on the root surface, and slices from the tomographic reconstruction revealed that the particles are hollow, consistent with microorganisms with a thin layer of Hg on the surface. Hg L3 XANES of ground-up plant roots and Hg L3 micro-XANES from microprobe analysis of micrometer-sized roots (60-120 μm in size) revealed three main types of speciation in both Spartina species: Hg-S ligation in a form similar to Hg(II) cysteine, Hg-S bonding as in cinnabar and metacinnabar, and methylmercury- carboxyl bonding in a form similar to methylmercury acetate. These results are interpreted within the context of obtaining a "snapshot" of mercury methylation in progress. © 2009 American Chemical Society., Cited By (since 1996):27, CODEN: ESTHA, ,
Author: Patty, Barnett, Mooney, Kahn, Levy, Liu, Pianetta, Andrews
Date: 2009-01-01T00:00:00Z

Title: Radiometric age validation of the yelloweye rockfish (Sebastes ruberrimus) from southeastern Alaska,
Description: The yelloweye rockfish (Sebastes ruberrimus), a dominant component of an important deep-water rockfish fishery of the Gulf of Alaska, is thought to be long-lived with an estimated longevity exceeding 100 years. For the purpose of monitoring stocks, age is routinely estimated by counting growth zones in otolith cross-sections using the break-and-burn technique; however, such age estimates for this species have remained unvalidated. To evaluate these age data, age estimations from the break-and-burn technique were corroborated by comparing results from transverse sectioning of otoliths. The agreement between the techniques was excellent and each technique had a very low coefficient of variation (3.6% and 4.5%). Radiometric age validation of these estimates was performed on the otolith core material (first three years of growth) of pooled age groups having an average estimated age of 27.4-101.4 years. Agreement was variable and somewhat subjective, but radiometric data support ages estimated from otolith growth zone counts. The strongest support for age that exceeds 100 years comes from the observation that as age derived from growth zones approached and exceeded 100 years, the sample ratios measured (210Pb:226Ra) approached equilibrium. The radiometric results of our study validate the estimates derived from growth zones and the age estimating procedures, which confirms that the longevity of yelloweye rockfish exceeds 100 years., Cited By (since 1996):22, CODEN: AJMFA, ,
Author: Andrews, Cailliet, Coale, Munk, Mahoney, O'Connell
Date: 2002-01-01T00:00:00Z

Title: Lead-radium dating provides a framework for coordinating age estimation of Patagonian toothfish (Dissostichus eleginoides) between fishing areas,
Description: Patagonian toothfish (Dissostichus eleginoides) or 'Chilean sea bass' support a valuable and controversial fishery, yet their life history is not well understood and longevity estimates range from ∼20 to > 50 years. In this study, lead-radium dating provided valid ages for juvenile to older adult groups, which were consistent with the counting of otolith growth zones in transverse otolith sections, and longevity estimates exceeding 30 years. Lead-radium dating revealed minor biases between the radiometric age and interpretation of growth zone counting for regional fishing areas monitored by two facilities, Center for Quantitative Fisheries Ecology (CQFE) and the Central Ageing Facility (CAF), using different age estimation techniques. For CQFE, under-ageing of ∼3.3 years was observed for individuals with estimated ages under 20 years. For the CAF, ages were overestimated for young fish and underestimated for the oldest fish. Lead-radium dating detected underlying problems in coordinating age estimation between geographically separated fish stocks, and provided a framework to objectively assess otolith interpretation and growth modelling between laboratories based on age-validated data. © CSIRO 2011., Fish and Fisheries, CODEN: AJMFA, ,
Author: Andrews, Ashford, Brooks, Krusic-Golub, Duhamel, Belchier, Lundstrom, Cailliet
Date: 2011-01-01T00:00:00Z

Title: Radiocarbon in otoliths of yelloweye rockfish (Sebasfes ruberrimus): A reference time series for the coastal waters of southeast Alaska,
Description: Atmospheric testing of thermonuclear devices during the 1950s and 1960s created a global radiocarbon (14C) signal that has provided a useful tracer and chronological marker in oceanic systems and organisms. The bomb-generated 14C signal retained in fish otoliths can be used as a time-specific recorder of the 14C present in ambient seawater, making it a useful tool in age validation of fishes. The goal of this study was to determine 14C in otoliths of the age-validated yelloweye rockfish (Sebastes ruberrimus) to establish a reference time series for the coastal waters of southeast Alaska. Radiocarbon values from the first year's growth of 43 yelloweye rockfish otoliths plotted against estimated birth year produced a 14C time series (1940-1990) for these waters. The initial rise of 14C occurred in 1958 and 14C levels rose to peak values (60-70‰) between 1966 and 1971, with a subsequent declining trend through the end of the record in 1990 (-3.2‰). In addition, the 14C data confirmed the longevity of the yelloweye rockfish to a minimum of 44 years and strongly support higher age estimates. This 14C time series will be useful for the interpretation of 14C accreted in biological samples from these waters., Cited By (since 1996):24, CODEN: CJFSD, ,
Author: Kerr, Andrews, Frantz, Coale, Brown, Cailliet
Date: 2004-01-01T00:00:00Z

Title: Bomb radiocarbon and tag-recapture dating of sandbar shark (Carcharhinus plumbeus),
Description: The sandbar shark (Carcharhinus plumbeus) was the cornerstone species of western North Atlantic and Gulf of Mexico large coastal shark fisheries until 2008 when they were allocated to a research-only fishery. Despite decades of fishing on this species, important life history parameters, such as age and growth, have not been well known. Some validated age and growth information exists for sandbar shark, but more comprehensive life history information is needed. The complementary application of bomb radiocarbon and tag-recapture dating was used in this study to determine valid age-estimation criteria and longevity estimates for this species. These two methods indicated that current age interpretations based on counts of growth bands in vertebrae are accurate to 10 or 12 years. Beyond these years, we could not determine with certainty when such an underestimation of age begins; however, bomb radiocarbon and tag-recapture data indicated that large adult sharks were considerably older than the estimates derived from counts of growth bands. Three adult sandbar sharks were 20 to 26 years old based on bomb radiocarbon results and were a 5- to 11-year increase over the previous age estimates for these sharks. In support of these findings, the tag-recapture data provided results that were consistent with bomb radiocarbon dating and further supported a longevity that exceeds 30 years for this species., Cited By (since 1996):3, Fish and Fisheries, CODEN: FSYBA, ,
Author: Andrews, Natanson, Kerr, Burgess, Cailliet
Date: 2011-01-01T00:00:00Z

Title: Recent increase in atmospheric deposition of mercury to California aquatic systems inferred from a 300-year geochronological assessment of lake sediments,
Description: Age-dated sediment cores from 4 remote lakes across California were analyzed for total Hg (Hg T) concentration as a function of pre- and post-industrialization. Particle size, magnetic susceptibility and organic C and N, were measured to determine if the Hg concentration in sediment cores could be related to atmospheric deposition and/or watershed processes. Results indicate that (a) for each lake modern (1970-2004) Hg T lake sediment concentrations have increased by an average factor of 5 times more than historic (pre-1850) Hg T concentrations; (b) the ratio of modern to pre-industrial lake sediment Hg T for these lakes are higher than estimated for other locations where atmospheric deposition is presumed to be the main source of Hg; (c) 2 of the 4 studied lakes demonstrated significant relationships between Hg T concentrations and percentage organic material (r 2 = 0.68 and p < 0.01; r 2 = 0.67 and p < 0.01) whereas the other two indicated no significant relationship (r 2 = 0.05 and p = 0.51; r 2 = 0.12 and p = 0.36). © 2007 Elsevier Ltd. All rights reserved., Cited By (since 1996):13, CODEN: APPGE, ,
Author: Sanders, Coale, Gill, Andrews, Stephenson
Date: 2008-01-01T00:00:00Z

Title: Age validation of quillback rockfish (Sebastes maliger) using bomb radiocarbon,
Description: Cited By (since 1996):26, , , ,
Author: Kerr, Andrews, Munk, Coale, Frantz, Cailliet, Brown
Date: 2005-01-01T00:00:00Z

Title: Investigations of Δ14C, δ13C, and δ15N in vertebrae of white shark (Carcharodon carcharias) from the eastern North Pacific Ocean,
Description: The white shark, Carcharodon carcharias, has a complex life history that is characterized by large scale movements and a highly variable diet. Estimates of age and growth for the white shark from the eastern North Pacific Ocean indicate they have a slow growth rate and a relatively high longevity. Age, growth, and longevity estimates useful for stock assessment and fishery models, however, require some form of validation. By counting vertebral growth band pairs, ages can be estimated, but because not all sharks deposit annual growth bands and many are not easily discernable, it is necessary to validate growth band periodicity with an independent method. Radiocarbon (14C) age validation uses the discrete 14C signal produced from thermonuclear testing in the 1950s and 1960s that is retained in skeletal structures as a time-specific marker. Growth band pairs in vertebrae, estimated as annual and spanning the 1930s to 1990s, were analyzed for Δ14C and stable carbon and nitrogen isotopes (δ13C and δ15N). The aim of this study was to evaluate the utility of 14C age validation for a wide-ranging species with a complex life history and to use stable isotope measurements in vertebrae as a means of resolving complexity introduced into the 14C chronology by ontogenetic shifts in diet and habitat. Stable isotopes provided useful trophic position information; however, validation of age estimates was confounded by what may have been some combination of the dietary source of carbon to the vertebrae, large-scale movement patterns, and steep 14C gradients with depth in the eastern North Pacific Ocean., Cited By (since 1996):28, CODEN: EBFID, ,
Author: Kerr, Andrews, Cailliet, Brown, Coale
Date: 2006-01-01T00:00:00Z

Title: Age of black coral (Antipathes dendrochristos) colonies, with notes on associated invertebrate species,
Description: In 2005, a dead 2.1-m high colony of the Christmas tree black coral, Antipathes dendrochristos Opresko, 2005, was collected from 106 m of water off southern California. Based on growth increment counts, a radiocarbon ( 14C) analysis, and an indirect corroboration by lead-210 dating from a second, live colony, the colony was about 140 yrs old when it died. The dead skeleton was heavily colonized by invertebrates with 2554 individuals living on the colony. Corophioid amphipods, sea anemones, brittle stars, and crinoids dominated this assemblage. Thus, along with living colonies, it is arguable that the destruction of dead antipatharian colonies may have as yet unknown effects on a range of deep-water organisms. © 2007 Rosenstiel School of Marine and Atmospheric Science of the University of Miami., Cited By (since 1996):13, Invertebrates, CODEN: BMRSA, ,
Author: Love, Yoklavich, Black, Andrews
Date: 2007-01-01T00:00:00Z

Title: Age, growth and radiometric age validation of a deep-sea, habitat-forming gorgonian (Primnoa resedaeformis) from the Gulf of Alaska,
Description: Cited By (since 1996):81, , , ,
Author: Andrews, Cordes, Mahoney, Munk, Coale, Cailliet, Heifetz
Date: 2002-01-01T00:00:00Z

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