Date Of Capture Research Articles

Migratory blackpoll warblers (Setophaga striata) make regional-scale movements that are not oriented toward their migratory goal during fall

BackgroundRegional scale movement patterns of songbirds are poorly known largely due to difficulties tracking small organisms at broad scales. Using an array of over 100 automated radio telemetry towers, we followed Blackpoll Warblers (Setophaga striata) during fall migration in the Gulf of Maine region, and assessed how their regional scale movement pathways varied with age, distance to natal origin, and capture date.ResultsMany individuals had movement paths that were not oriented towards their migratory goal (‘indirect movement patterns’), regardless of age, distance to natal origin, or time of season. The probability of moving in indirect patterns, and the total tracking duration, decreased with capture date. The extent of indirect movement patterns varied considerably between individuals. Excluding direct flight patterns consistent with traditional migratory movements, adults tended to make more flights and moved in more tortuous patterns than hatch-years. Adults and individuals from more westerly natal origins were more likely to move south-west through time.ConclusionsA greater proportion of individuals made movements that were not oriented towards the migratory than expected. A decrease in tracking duration with capture date indicates that individuals prioritize time as the season progresses. The shorter, indirect movement patterns may be a more complete representation of ‘reverse migration’ at a barrier or ‘landscape-scale stopovers movements’. The longer distances travelled are inconsistent with expected behaviour, even in front of a barrier. The extent of movement we observed indirectly suggests that flight is not as costly to individuals in a migratory state as is commonly assumed. Since adults were observed to move more than hatch-years, we suggest that the indirect movement patterns we observed are not accidental, and may provide some advantage to the individuals that undertake them.

Bayesian model-based age classification using small mammal body mass and capture dates

Bayesian model-based age classification using small mammal body mass and capture dates

Plumage colouration variability of male Bluethroats (Luscinia svecica cyanecula) wintering in SE Iberia

Male colouration has a key role in signalling individual quality during the breeding season. Although winter plumage probably correlates with summer plumage, few studies have focused on the determinants of male colouration during the non-breeding period. If plumage colouration is related to an individual’s age or is strongly correlated with body condition during the non-breeding period, this trait could be used by conspecifics to assess quality, origin or status of a given individual.Here,we analysed plumage colouration and body size of male Bluethroats (Luscinia svecica cyanecula) wintering in SE Iberia. We found that young individuals had narrower black bands and wider white bands than adult individuals in their throat patch.Also, thewidth of the chestnut band increased with later capture date. Finally, blue throat colouration was positively correlated with tail length and negatively correlatedwith tarsus length.We could not find any significant relationship between throat patch colouration and bodymass.We concluded that individual’s age and capture date were significantly related to black and chestnut throat colouration, respectively. Therefore, these coloured bands could provide reliable cues on individual’s age and their geographical origins. The variability of plumage colouration of wintering Bluethroats provides an excellent study system in which to test further hypotheses on the role of the throat patch colouration outside the breeding season.

Regional variation of gene regulation associated with storage lipid metabolism in American glass eels (Anguilla rostrata)

Variation in gene regulation may be involved in the differences observed for life history traits within species. American eel (Anguilla rostrata) is well known to harbor distinct ecotypes within a single panmictic population. We examined the expression of genes involved in the regulation of appetite as well as lipid and glycogen among glass eels migrating to different locations on the Canadian east coast and captured at two different periods of upstream migration. Gene expression levels of three reference and five candidate genes were analyzed by real-time PCR with Taqman probes in recently captured wild glass eels. All gene transcripts were detected in glass eels. Of the five candidate genes, bile salt activated and triacylglycerol lipases were respectively 7.65 and 3.25 times more expressed in glass eels from the St. Lawrence estuary than in those from Nova Scotia, and there was no effect related to the two-week difference in capture date. These two genes explained 82.41% of the dissimilarity between the two rivers. In contrast, glycogen phosphorylase, ghrelin, and leptin receptor genes showed no significant differences in gene transcription. These results confirmed at the molecular level an observation that was recently made at the phenotypic level that glass eels from the St. Lawrence estuary have a greater capacity to use lipid reserves to sustain their metabolic needs. These observations add to the body of evidence supporting the hypothesis that regional phenotypic variation observed in American eel is determined early in life and that part of this variation is likely under genetic control.

Validation of age determination using otoliths of the European anchovy (Engraulis encrasicolus L.) in the Bay of Biscay

Validation of the age determination procedure using otoliths of European anchovy in the Bay of Biscay was achieved by monitoring very strong year-classes in successive spring catches and surveys, as well as the seasonal occurrence of edge types. Historical corroboration of the ageing method was obtained by cross-correlation between successive age groups by year-classes in catches and surveys (1987–2013). Summary annual growth in length is also presented. Yearly annuli consist of a hyaline zone (either single or composite) and a wide opaque zone, disrupted occasionally by some typical checks (mainly at age-0 and age-1 at peak spawning time). Age determination, given a date of capture, requires knowledge of the typical annual growth pattern of otoliths, their seasonal edge formation by ages and the most typical checks. Most opaque growth occurs in summer and is minimal (translucent) in winter. Opaque zone formation begins earlier in younger fish (in spring), and this helps distinguish age-1 from age-2+.

고등어(Scomber japonicus) 이석의 초륜 형성 및 연령 사정

【First annulus formation and age determination of otoliths were examined for chub mackerel Scomber japonicus collected in Korean waters over the one year from January to December in 2009. Translucent zone was regarded as an annual mark. Age interpretation criteria was based on the data of the number of translucent zone, capture date, and edge type of the otolith, assuming the nominal birthday to be 1 January. Monthly changes in mean marginal index indicated that translucent zone was formed once a year, mainly in June. The otolith of 0-ring group was detected comparing the progression by month of the smaller fish length, appearing to be a single first opaque zone. The average distance from the core to the first translucent zone was ~1.77 mm, provided as supplementary information to increase ageing accuracy. The ageing criteria for chub mackerel was made to determine correct year-class with the purpose of effective stock assessment. This method using nominal birthdate and edge type analysis could estimate age of fish closer to the true age than purely counting the number of translucent zone on a whole otolith.】

Reporting of Cardiovascular Medical Device Adverse Events to Pharmaceuticals and Medical Devices Agency, Japan

BackgroundMarketing authorization holders (MAHs) are obligated to report adverse events (AEs) within 15days (some cases 30days) to the Pharmaceuticals and Medical Devices Agency (PMDA) of Japan. MethodsTo analyze the timeliness of AE reporting to the PMDA, 6610 reports for five categories of cardiovascular devices were retrieved. Two durations were calculated: (1) time from the date the AE occurred to that when the MAH captured it (DOC: days); and (2) time from the date of MAH capture to that of MAH report (DCR: days). Number of DOC>15days (DOC15) and delayed reports (DCR>15 or 30days) were also calculated. ResultsAEs included 9.2% deaths and 7.5% non-recoveries. DOC15 and delayed reports were 51.0% and 10.9%, respectively. By multivariate analysis, DOC15 was associated with foreign AE, device category, MAH, patient outcome, event category, and AE that had to be reported within 15 or 30days (AE15/30). Delayed report was associated with device category, MAH, patient outcome, event category, and AE15/30. CommentsAlthough Japanese MAHs complied with the obligation to report AEs, they often failed to share AEs with healthcare providers. Registry may be a potential solution, although the cooperation of healthcare providers to input data is essential.

An Invasive Mammal (the Gray Squirrel, Sciurus carolinensis) Commonly Hosts Diverse and Atypical Genotypes of the Zoonotic Pathogen Borrelia burgdorferi Sensu Lato.

Invasive vertebrate species can act as hosts for endemic pathogens and may alter pathogen community composition and dynamics. For the zoonotic pathogen Borrelia burgdorferi sensu lato, the agent of Lyme borreliosis, recent work shows invasive rodent species can be of high epidemiological importance and may support host-specific strains. This study examined the role of gray squirrels (Sciurus carolinensis) (n = 679), an invasive species in the United Kingdom, as B. burgdorferi sensu lato hosts. We found that gray squirrels were frequently infested with Ixodes ricinus, the main vector of B. burgdorferi sensu lato in the United Kingdom, and 11.9% were infected with B. burgdorferi sensu lato. All four genospecies that occur in the United Kingdom were detected in gray squirrels, and unexpectedly, the bird-associated genospecies Borrelia garinii was most common. The second most frequent infection was with Borrelia afzelii. Genotyping of B. garinii and B. afzelii produced no evidence for strains associated with gray squirrels. Generalized linear mixed models (GLMM) identified tick infestation and date of capture as significant factors associated with B. burgdorferi sensu lato infection in gray squirrels, with infection elevated in early summer in squirrels infested with ticks. Invasive gray squirrels appear to become infected with locally circulating strains of B. burgdorferi sensu lato, and further studies are required to determine their role in community disease dynamics. Our findings highlight the fact that the role of introduced host species in B. burgdorferi sensu lato epidemiology can be highly variable and thus difficult to predict.

Field Metabolic Rate Is Dependent on Time-Activity Budget in Ring-Billed Gulls (Larus delawarensis) Breeding in an Anthropogenic Environment.

Environmental and behavioral factors have long been assumed to affect variation in avian field metabolic rate (FMR). However, due to the difficulties in measuring continuous behavior of birds over prolonged periods of time, complete time-activity budgets have rarely been examined in relation to FMR. Our objective was to determine the effect of activity (measured by detailed time-activity budgets) and a series of extrinsic and intrinsic factors on FMR of the omnivorous ring-billed gull (Larus delawarensis). The experiment was conducted during the incubation period when both members of the pair alternate between attending the nest-site and leaving the colony to forage in aquatic and anthropogenic environments (city, agricultural). FMR was determined using the doubly labeled water method. Time-activity budgets were extrapolated from spatio-temporal data (2-5 days) obtained from bird-borne GPS data loggers. Gulls had low FMRs compared to those predicted by allometric equations based on recorded FMRs from several seabird species. Gulls proportioned their time mainly to nest-site attendance (71% of total tracking time), which reduced FMR/g body mass, and was the best variable explaining energy expenditure. The next best variable was the duration of foraging trips, which increased FMR/g; FMR/g was also elevated by the proportion of time spent foraging or flying (17% and 8% of tracking time respectively). Most environmental variables measured did not impact FMR/g, however, the percent of time birds were subjected to temperatures below their lower critical temperature increased FMR. Time-activity budgets varied between the sexes, and with temperature and capture date suggesting that these variables indirectly affected FMR/g. The gulls foraged preferentially in anthropogenic-related habitats, which may have contributed to their low FMR/g due to the high availability of protein- and lipid-rich foods. This study demonstrates that activities were the best predictors of FMR/g in ring-billed gulls, thus providing strong support for this long-standing theory in bioenergetics.

Cascading effects of habitat on maternal condition and life-history characteristics of neonatal mule deer

The condition of maternal female mammals greatly influences life-history characteristics of their young, but interactions between habitat and maternal condition and their combined influences on birth characteristics and survival of neonates are less well understood, especially in free-ranging populations. We monitored survival of neonatal mule deer (Odocoileus hemionus) inhabiting 2 contrasting ecotypes in Idaho: aspen woodlands (Populus tremuloides) in southeast Idaho (Caribou Mountains) and mixed-conifer grasslands (lodge-pole pine, Pinus contorta; Douglas-fir, Pseudotsuga menziesii) in central Idaho (Salmon River Mountains). We expected the Caribou Mountains to offer better forage and greater concealment cover than the Salmon River Mountains. We tested for an array of maternal influences on neonatal deer inhabiting those dissimilar ecosystems. We monitored 96 neonates from date of capture to 5 months of age (n = 44 in the Caribou Mountains, 2010; n = 52 in the Salmon River Mountains, 2011). Survival and birth characteristics consistently diverged between study areas, whereas timing of births was similar. Female deer from the Salmon River Mountains exhibited poor maternal condition and small litter sizes compared with females from the Caribou Mountains. Young from the Salmon River Mountains exhibited lower rates of growth, occupied bedding sites with less concealment cover, and subsequently experienced lower survival from birth to 5 months of age, compared with neonates from the Caribou Mountains. Cause of deaths for young mule deer on both study sites was mostly from predation. Our findings emphasize the potential role that habitat plays in the population dynamics of mule deer via cascading effects on physical condition, reproduction, and survival. Changes in habitat, potentially associated with changing climate, fire regimes, and land uses, probably have contributed to the widespread declines in populations of mule deer during recent decades.

Spatial segregation, dispersion and migration in early stages of polar cod Boreogadus saida revealed by otolith chemistry

Arctic marine food webs are centered on polar cod (Boreogadus saida), a small, largely pelagic gadid, which movement and migration remain unclear, especially for the early life stages. The present study examined the otolith chemistry of juvenile polar cod from six oceanographic regions of the Arctic Ocean in order to document patterns of spatial segregation, dispersion and migration during the species early life. The freshwater winter refuge hypothesis, suggesting that polar cod larvae start to hatch in winter in freshwater-influenced regions but only later in the season in purely marine regions, was also tested. Five elemental ratios (Li/Ca, Mg/Ca, Mn/Ca, Sr/Ca and Ba/Ca) were analyzed by laser ablation inductively coupled plasma mass spectrometry in three otolith zones representing the egg, larval and juvenile stages. The concentration of each of the five elements at the edge of the otoliths, corresponding to incorporation shortly before capture, was significantly correlated with surface salinity and temperature at capture site and date. Otolith chemistry differed between juveniles from freshwater-influenced regions (Laptev Sea, Hudson Bay Amundsen Gulf) and those from purely marine regions (Lancaster Sound, Baffin Bay, Frobisher Bay), in agreement with dissolved concentrations of at least some of the target elements in the Arctic Ocean. Discriminant function analyses including all five elements provided valuable information on the species population structure and dispersion of early stages. The correspondence between otolith Mn/Ca, Ba/Ca and vertical profiles of dissolved Mn and Ba in the water column may reflect the ontogenetic vertical migration of juvenile polar cod in late-summer and fall.

Stock‐Specific Size and Timing at Ocean Entry of Columbia River Juvenile Chinook Salmon and Steelhead: Implications for Early Ocean Growth

AbstractJuvenile salmon transitioning from freshwater to marine environments experience high variation in growth and survival, yet the specific causes of this variation are poorly understood. Size at and timing of ocean entry may contribute to this variation because they influence both the availability of prey and vulnerability to predators. To explore this issue, we used stock assignments based on genetic stock identification and internal tags to document the stock‐specific size and timing of juvenile hatchery and presumed wild Columbia River Chinook SalmonOncorhynchus tshawytschaand steelheadO. mykissat ocean entry during 2007–2011. We found that juvenile salmon and steelhead had consistent stock‐specific capture dates, with lower‐river stocks typically having earlier timing than those originating farther upstream. Mean size also varied among stocks and was related to hatchery practices. Hatchery yearling Chinook Salmon and steelhead were consistently larger than wild fish from the same stocks, although timing in the estuary was similar. In contrast, hatchery subyearling Chinook Salmon were of similar size to wild fish but entered the ocean up to a month earlier. We evaluated the potential importance of these traits on early marine growth by estimating stock‐specific growth rates for Chinook Salmon caught in estuarine and ocean habitats. Growth rates were related to relative ocean entry timing, with lower growth rates for stocks that had only recently arrived in marine waters. Our results demonstrate that stocks within a single basin can differ in their size and timing of ocean entry, life history traits that contribute to early marine growth and potentially to the survival of juvenile salmon. Our results also highlight the necessity of considering stock‐specific variation in life history traits to understand salmon ecology and survival across the entire life cycle.Received January 16, 2015; accepted April 28, 2015

Otoliths as a proxy for seasonality: The case of Micropogonias furnieri from the northern coast of San Matías Gulf, Río Negro, Patagonia, Argentina

This article presents the preliminary results of a seasonality study on Micropogonias furnieri otoliths from the northern coast of the San Matías Gulf, Río Negro, Argentina. First, we analyze modern M. furnieri otoliths from a reference collection, which provides a necessary framework for assessing the viability of the method. Data from the modern reference collection comprise more than 360 otolith section cuts from fish with known capture dates that span a whole year. Second, we analyze otolith section cuts from zooarchaeological fish remains, a total of 61 samples, collected from different archaeological sites along the northern coast of the San Matías Gulf, Patagonia, Argentina. Using data from the two analyses, we generate a strong macro-regional model of seasonality. A comparison between the modern and ancient otoliths also provides insights into the seasonality of human occupation and M. furnieri exploitation along the Northern Río Negro coastline from the mid-to late Holocene. Our data show that M. furnieri fishing activities in the area primarily took place between November and January. Application of our method demonstrates its advantages and limitations for more general application in a wider range of archaeological studies.

British Ornithologists' Union Records Committee: 43rd Report (October 2014)

British Ornithologists' Union Records Committee: 43rd Report (October 2014)

Morphological Discrimination of Genetically Distinct Chinook Salmon Populations: an Example from California's Central Valley

AbstractWe compared a length‐at‐date growth model to truss network (morphometric) models for classifying emigrating juvenile (age 0 through age 1) California Central Valley Chinook Salmon Oncorhynchus tshawytscha to three genetically identified races at upstream (salmon generally younger and smaller) and downstream (salmon generally older and larger) monitoring stations. Morphometric models including capture date and head to standard length ratio performed better than the growth model at distinguishing genetically assigned fall‐run and late fall‐run juveniles; prediction accuracy increased from 54.6% to 63.8% for upstream salmon and from 17% to 73% for downstream salmon. The growth model may over inflate downstream estimates of federally listed Chinook Salmon by misidentifying fall and late‐fall runs (nonlisted) as winter and spring runs (both listed) as much as 83% of the time. Morphometric models did not improve run assignment for the listed runs; the growth model outperformed morphometric models at downstream stations. Morphometric models including head shape and sample date had similar accuracy measures to models, including multiple fish measurement ratios, suggesting head shape is the strongest predictor of the juvenile Central Valley Chinook Salmon race. Our results indicate morphometric modeling can improve identification of nonlisted juvenile Central Valley Chinook Salmon from federally listed runs, potentially benefitting monitoring, water management, and protection of sensitive species.Received May 5, 2014; accepted August 13, 2014

Migratory Movements and Mortality of Peregrine Falcons Banded in Greenland, 1972–97

In 1972 we initiated a long-term study of Peregrine Falcons Falco peregrinus in West Greenland to evaluate population status and describe general breeding ecology. The study area encompassed approximately 6050 km2, spanning the area from the edge of the inland ice cap westward to the coast. From 1972 to 1997, we banded 1896 peregrines (1771 nestlings, 125 adults). Encounters of banded peregrines (n = 114) outside the study area occurred at locations from Greenland to Uruguay. In contrast to the equal sex ratio recorded in broods at banding, the sex ratio of nestling encounters was significantly skewed toward females. The majority (54%) of encounters involved capture and release by other falcon researchers, particularly those operating banding stations along the Eastern Seaboard and in southern Texas. Peregrines from Greenland appeared to reach wintering areas by late October or early November. Although male peregrines wintered significantly farther south than females, there was no significant difference in the mean date of capture along the East Coast of the United States in the hatch year (mean = 9 October ± 2.5 days for males and 9 October ± 1 day for females). Spring migration appeared to commence in early April, with breeding birds back on the study area by late May or early June. Despite the extensive recent use of satellite telemetry, long-term banding continues to play an important role in studies of peregrine migration, natal dispersal, and survival.

First estimates of age and growth of juvenile black anglerfish (Lophius budegassa), in north-eastern Atlantic waters

Growth increments in the lapilli otoliths of the black anglerfish (Lophius budegassa) were used to investigate its early life history. Assuming that the primary increments are deposited daily, age and hatch dates were determined by counting these increments in the lapilli of 33 juvenile fish collected during autumn bottom trawl surveys in the Bay of Biscay. The estimated ages of juveniles ranged from 71 to 165 days (60 to 202mm total length) while the growth rate ranged from 1.19 to 1.48mmday−1 for that period. The age–length relationship was best described by the power function TL=0.311 age (days)1.26. Hatch date was back-calculated from the date of capture and results indicate a broad spawning season, mainly taking place from May to July. Juveniles of up to 200mm total length collected in October were born the same year and belonged to age class 0. Although the periodicity of the primary increments has not yet been validated, our results, based on this assumption, would corroborate, for the first time using micro-increment analysis, a faster growth pattern of early stages of L. budegassa in Atlantic waters than previously thought, in agreement with the evidence obtained for the species in the Mediterranean Sea.

Dead before detection: addressing the effects of left truncation on survival estimation and ecological inference for neonates

SummaryNeonate survival is a key life history trait, yet remains challenging to measure in wild populations because neonates can be difficult to capture at birth. Estimates of survival from neonates that are opportunistically captured might be inaccurate because some individuals die before sampling, resulting in data that are left truncated. The resulting overestimation of survival rates can further affect ecological inference through biased estimates of covariate effects in survival models, yet is not addressed in most studies of animal survival. Here, we quantify the effects of left truncation on survival estimates and subsequent ecological inference.Vaginal implant transmitters (VITs) enable capture of ungulates at birth, yielding data without left truncation. The effects of left truncation on survival estimation were quantified using age‐dependent survival models for VIT and opportunistically captured neonatal deer. Differences in daily survival rates (DSRs) and cumulative survival probability were calculated for the first 70 days of life. In addition, left truncation was simulated by removing fawns that died during the first 1 or 2 days of life from the VIT‐caught sample, isolating the effect of left truncation.Cumulative probability of survival during the first 70 days of life was overestimated by 7–23% for fawns caught opportunistically compared with those caught by VIT, depending on model design. Differences in DSRs were large at age 1 day, but had converged by age 30 days. Simulated left truncation resulted in overestimates of survival of up to 31%. Model selection and covariate coefficients were strongly affected by left truncation, producing spurious ecological inference, including changes to sign and/or magnitude of inferred effects of all covariates.We recommend (i) every effort be made to capture neonates; (ii) consistent capture methods, using at least in part non‐truncating techniques, be implemented across years and study areas; and (iii) exclusion of left‐truncated data from survival estimates until DSRs converge with those calculated from non‐truncated data. This work emphasizes the importance of accounting for left truncation in survival estimation for any species with strong age‐dependent survival in order to prevent biased conclusions produced by sampling method rather than true ecological effects.

Non cystic fibrosis bronchiectasis: A longitudinal retrospective observational cohort study of Pseudomonas persistence and resistance

The hallmark of non-cystic fibrosis bronchiectasis is recurrent bronchial infection, yet there are significant gaps in our understanding of pathogen persistence, resistance and exacerbation frequencies. Pseudomonas aeruginosa is a key pathogen thought to be a marker of disease severity and progression, yet little is known if the infection risk is seen in those with milder disease or if there is any potential for eradication. These data are important in determining risk stratification and follow up. A retrospective review of consecutive adult patients attending a specialist UK bronchiectasis clinic over a two-year recruitment period between July 2007 and June 2009 was performed. Analysis of our primary outcome, longitudinal microbiological status, was recorded based on routine clinical follow-up through to data capture point or date of death. Patients were stratified by lung function and infecting organism. 155 patients (mean (SD) age 62.2 (12.4) years; 60.1% female) were identified from clinic records with microbiological data for a median (IQR) follow up duration of 46 (35-62) months. Baseline mean FEV1% predicted was 60.6% (24.8) with mean exacerbation frequency of 4.42/year; 73.6% reported 3 or more exacerbations/year. Haemophilus influenzae was isolated in 90 (58.1%) patients and P. aeruginosa in 78 (50.3%) patients with persistent infection in 51 (56.7%) H. influenzae and 47 (60.3%) P. aeruginosa, respectively. Of the P. aeruginosa colonised patients, 16 (34%) became culture negative on follow-up with a mean of 5.2 negative sputum cultures/patient. P. aeruginosa was isolated from 5 out of 39 patients (12.8%) with minimal airflow limitation as compared to 18 out of 38 patients (47.4%) with severe airflow limitation. Although hospital admissions were significantly higher in the P. aeruginosa infected group (1.3 vs. 0.7 admissions per annum, p=0.035), overall exacerbation rates were the same (4.6 vs. 4.3, p=0.58). Independent predictors of P. aeruginosa colonisation were low FEV1% predicted (OR 2.46; 95% CI 1.27-4.77) and polymicrobial colonisation (OR 4.07; 95% CI 1.56-10.58). 17 (11%) patients were infected with multi-resistant strains; however, none were pan-resistant. P. aeruginosa is associated with greater persistent infection rates and more hospital admissions than H. influenzae. Exacerbation rates, however, were similar; therefore H. influenzae causes significant out-patient morbidity. P. aeruginosa infection occurs across all strata of lung function impairment but is infrequently multi-resistant in bronchiectasis. Careful microbiology follow up is required even in those with well-preserved lung function.

Validated age estimates for large white sharks of the northeastern Pacific Ocean: altered perceptions of vertebral growth shed light on complicated bomb Δ14C results

Age validation studies of large shark species using bomb radiocarbon (14C) dating have revealed that the growth of vertebrae can cease in adults. In a previous study of white sharks (Carcharodon carcharias) of the northeastern Pacific Ocean the latest growth material (leading edge of the corpus calcareum) was assigned a known date-of-formation assumed to coincide with the individual’s date of capture. This perspective prevented the assignment of older years of formation (a shift in age) to this material, leading to complicated results and no validated age estimates. A reanalysis of the bomb 14C data, in light of the recent findings for other species, has led to a validated lifespan estimate exceeding 30 years for white sharks of the northeastern Pacific Ocean.