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Age data are crucial for understanding and managing target species in commercial and recreational fisheries. Octopus catches are increasing worldwide, yet ageing methods are still in their infancy. Octopus age is estimated by counting growth increments in stylets and beaks. These increments have been validated as daily in some species or assumed to be daily in other species. Here, we conducted an age validation study on both the stylets and beaks of a commercial octopus species (Octopus berrima). Subsequently, we compared and assessed the readability of growth increments in beaks and stylets of wild-caught O. berrima. We found that increment periodicity was nondaily for both structures, with increment periodicity also varying between structures (0.75 increments per day for stylets and 0.53 increments per day for beak). This study highlights the importance of validating increment periodicity for different octopus species and for both stylets and beaks to obtain accurate age and growth data. Without accurate age data, a species may be incorrectly managed with the potential for negative effects on the sustainability of wild populations. [ABSTRACT FROM AUTHOR]

Treated wastewater can partly meet the requirements of water for irrigating tree crops in dry areas to better utilize, produce biomass and reduce land degradation. Seedlings of Acacia nilotica, Azadirachta indica, Eucalyptus camaldulensis, Prosopis cineraria, P. juliflora, Tamarix aphylla, Salvadora persica, S. oleoides and Tecomella undulata were planted and irrigated with bore-well (BW) and treated wastewater (WW) at ½ET (Evaporation-transpiration) and ¾ET. Plants irrigated at BW1/2 attained less height and collar diameter, and showed low growth increments and dry biomass. These variables increased by 1.2-2.0-fold at WW3/4 irrigation. Plants produced 1.4-fold higher biomass with WW over BW, whereas it was 1.5-fold higher at ¾ET over ½ET. Responses of species to BW/WW irrigation differed in biomass allocation to roots and other parts as a mechanism to uptake water and nutrients. Conclusively, A. nilotica, A. indica, P. juliflora and T. aphylla had stronger preference to increased irrigation level, whereas E. camaldulensis, S. persica, S. oleoides and T. undulata had preferred nutrients added through treated wastewater. A. nilotica, E. camaldulensis, P. juliflora and A. indica were best species in growth and biomass production and wastewater utilization. These can be replicated in urban afforestation to enhance bio-product and reduce degradation in environmental quality. Wastewater (WW) is an alternative source of water in dryland afforestation. Wastewater was characterized and utilized in growing tree plantation in Indian arid zone. Plant growth and biomass increased with treated wastewater irrigation. Responses of different species to wastewater differed depending on their phytoremediation ability by nutrient uptake and biomass distribution. Tree species differed in their preferences to increased quantity of irrigation water and nutrients added through wastewater application. [ABSTRACT FROM AUTHOR]

The concept of growth rings is little discussed in the literature and their treatment remains somewhat confusing in terms of the diversity of structures described. This situation has a major impact on the study of growth rings in tropical species, in which variations and complexity are greater and accuracy of identification less good. The rigid conceptual delimitations used by dendrochronologists and wood anatomists of temperate regions cannot be applied to the study of growth rings in most tropical species, which has led to neglect of this subject. With the objective of discussing the concept of growth rings, the present study consists of a survey of anatomical, periodicity, causal and evolutionary aspects of the treatment of these structures as evidenced in previous studies, and the evaluation of their application and limitations to the development of this concept. Anatomical aspects arise through radial integrity, or the presence of early and late wood; the degree of distinction of the rings, which may vary from well to poorly defined; and tangential continuity, meaning that rings may form a complete circle in the transverse section of the trunk, or instead be tangentially discontinuous, lens‐shaped or in wedges. In addition there are a diversity of anatomical markers which enable us to recognize growth rings. Regarding periodicity, the rings may be annual, infra‐annual or supra‐annual. Causal aspects include genetic, endogenous and environmental components. Evolutionary aspects continue to be insufficiently investigated, and although most comparative studies treat growth rings recognized by different markers as though they were a single character, it remains questionable whether they can be regarded as homologous or the result of homoplasy. We conclude that the elaboration of a robust but broad definition which can include all the variation observed in growth rings of tropical species is a complex task, which is only possible by overcoming the restrictions adopted by dendrochronologists and wood anatomists of temperate regions for whom growth rings are essentially annual, strongly demarcated, tangentially continuous and restricted to the most pronounced markers. [ABSTRACT FROM AUTHOR]

Recent research has indicated through chemical tagging of some species of decapod crustacean that the mesocardiac, zygocardiac, and pterocardiac ossicles of the gastric mill are retained through molting and contain apparent growth increments potentially indicative of age. Though other recent studies have suggested that in some decapod species, these ossicles are either lost in the stomach exuvia at molting, or are partially resorbed prior to molting. This study investigated the fate of the gastric mill ossicles of Nephrops norvegicus throughout the molt cycle, in order to ascertain their utility for age determination. Wild-caught individuals were immersed in a calcein solution to stain the ossicles, reared in an aquaculture facility, and sacrificed at different stages of the molt cycle. In all individuals sacrificed less than 24 h after molting, the mesocardiac, zygocardiac, and pterocardiac ossicles of the gastric mill were found loose within the stomach of the individual, no longer attached to the stomach wall, among the disintegrated gastroliths. New ossicles are subsequently calcified postmolt to support the gastric mill and stomach wall. The same phenomenon of ossicle loss was also observed in two Austropotamobius pallipes individuals sacrificed 1 h postmolt. In some N. norvegicus individuals sacrificed at varying periods of time postmolt, the calcein stain was reincorporated into the newly calcified ossicles. It is suggested that this is because once the calcifying gastric mill is strong enough to cope with food, the old ossicles and gastroliths are digested, and their calcium, to which the calcein is bound, is resorbed. The results of this study indicate that the growth increments previously observed within the gastric mill ossicles of N. norvegicus are unlikely to be of annual periodicity, but are a result of the postmolt calcification process. It therefore seems unlikely that N. norvegicus can be directly aged using the gastric mill ossicles. This may be the case for a number of decapod crustacean species. [ABSTRACT FROM AUTHOR]

Octopus vulgaris is a viable candidate for commercial aquaculture, but rearing procedures might stress individuals and result in diminished growth and survival. This study investigated the relationship between possible stress sources (tank transposition and syphoning) when rearing O. vulgaris paralarvae and the deposition pattern of growth increments in their beak microstructure. Light intensity at the facility was heterogeneous, and accounted for with an experimental design consisting of blocks without replicates. Growth and survival were estimated and possible effects of handling were tested for both parameters. Increments and stress marks were counted in 120 paralarval upper jaws ( UJ), and the number of UJs with a mark on the day of stress application (day 8) was quantified. Differences in light intensity, diet quantity and total number of marks in the UJ were also compared between treatments. Growth and survival were statistically similar between treatments, although the control treatment showed a tendency for higher survival rates. Age at first increment deposition coincided with day 1 of experiment, and a 1 increment day−1 deposition rate was validated for the experiment duration. The number of stress marks was significantly different between the control and other treatments, indicating that handling might cause stress and that marks can be used as a biomarker for stress, although the occurrence of stress marks on day 8 was not significantly different. Light intensity and diet might have also been relevant stressors and confounded the results. The results herein presented are important for improving rearing conditions for O. vulgaris paralarvae. [ABSTRACT FROM AUTHOR]

Abstract: The present study was carried out to validate the daily deposition and age estimation by using beak rostrum sagittal sections increments of cultivated Octopus maya (Voss and Solís, 1966). This study validates for first time the periodicity of beak increments by using animals of known age. We analyzed the rostrum sagittal sections (RSS) of upper and lower beaks in 40 juveniles of O. maya divided into four age groups (63, 87, 105 and 122 days) with 10 individuals per group. The animals were fed with a soft diet allowing obtaining age estimations not affected by the beak erosion. At the same time 50 animals were sampled every 20 days until 120 days old to obtain an age-body wet weight (BW) curve which could be compared with the age-BW curve obtained using age estimations from beaks. Co-variance analysis showed no statistical differences between both curves. The number of increments present in the beaks corresponded with the number of days from hatchling. Therefore, it was possible to validate that a growth increment corresponds to a day of life in O. maya, confirming that, up to 122 days old, the beaks counts can be used to determine the age of O. maya. [Copyright &y& Elsevier]

Above-ground thermonuclear weapons testing from 1952 through 1962 nearly doubled the concentration of radiocarbon (14C) in the atmosphere. As a result, organic material formed during or after this period may be radiocarbon-dated using the abrupt rise and steady fall of the atmospheric 14C concentration known as the bomb-curve. We test the accuracy of accelerator mass spectrometry radiocarbon dating of 29 herbivore and plant tissues collected on known dates between 1905 and 2008 in East Africa. Herbivore samples include teeth, tusks, soft tissue, hair, and horn. Tissues formed after 1955 are dated to within 0.3-1.3 y of formation, depending on the tissue type, whereas tissues older than Ca. 1955 have high age uncertainties (>17 y) due to the Suess effect. 14C dating of tissues has applications to stable isotope (paleo)ecology and wildlife forensics. We use data from 41 additional samples to determine growth rates of tusks, molars, and hair, which improve interpretations of serial stable isotope data for (paleo)ecological studies. 14C dating can also be used to calculate the time interval represented in periodic histological structures in dental tissues (i.e., perikymata), which in turn may be used as chronometers in fossil teeth. Bomb-curve 14C dating of confiscated animal tissues (e.g., ivory statues) can be used to determine whether trade of the item is legal, because many Convention of International Trade of Endangered Species restrictions are based on the age of the tissue, and thus can serve as a powerful forensic tool to combat illegal trade in animal parts. [ABSTRACT FROM AUTHOR]

The growth of age-1 Pacific saury Cololabis saira was compared based on an analysis of the body-length frequency distributions, radius of the annual ring (otolith hyaline zones; ROH), and growth patterns in otolith increments. Fish were sampled at various locations between off the Japanese coast (144°E) and in the Central Pacific (160°W) in June and July 2006, and the measurements were compared among the stations ranging over six longitudinal areas, each with a longitudinal area of 10°. The mode of body-length frequency distributions of age-1 fish was larger in fish sampled west of 160°E (size class modes of 32.0-32.5 and 31.5-32.0 cm, respectively, in each 10° longitude area) than in those sampled east of 170°E (28.5-29.0 or 29.0-29.5 cm in 3 areas). The ROH was also larger in the former group (west of 160°E) than in the latter group (east of 170°E), but hatch periods of these two groups and age in days when the hyaline zones form in August or September did not differ based on the analysis of otolith growth increments. The growth difference occurred in the period between when the fish started their northward migration and when the hyaline zone was formed. These results indicate that the habitats of the two groups were separate until at least June or July of their second year of life. [ABSTRACT FROM AUTHOR]

The re-discovery of nine petrographic slides from the late 19th century at the palaeontological collections of the University of Zurich, showing thin-sectioned ichthyosaur teeth, revealed these slides be the only preserved remains of the historical collection of Upper Jurassic ichthyosaurs from the Bavarian State Collection for Palaeontology and Geology; fossil material which, up to now, was thought to have been completely destroyed during World War II. Here the history of these slides, from their origin in Munich as part of the doctoral thesis of Franz Bauer () to their rediscovery in Zurich in 2010 is presented. Furthermore, a complete overview of all slides is given to elucidate their scientific value with the background of up-to-date knowledge of ichthyosaur dentition and tooth histology, including aspects of tissue and growth mark identification. As such, the sectioned teeth show an exposed layer of acellular cementum at the tooth neck, and sets of short and long period growth lines in the orthodentine. The slides of one tooth are part of the original syntype material of Aegirosaurus leptospondylus (W agner). They reveal an oval rather than a rectangular shape of the root, as well as the presence of peculiar vascular canals, interpreted as secondary osteodentine deposition, in the peri-pulpal orthodentine. [ABSTRACT FROM AUTHOR]

Barratt, I. M., and Allcock, A. L. 2010. Ageing octopods from stylets: development of a technique for permanent preparations. – ICES Journal of Marine Science, 67: 1452–1457.Previous attempts at ageing octopods from stylets have relied on preparations that deteriorate with time. Some techniques require an immediate photographic record, others allow real-time enumeration but do not provide a permanent archive. A technique is described that produces permanent and archivable preparations of octopod stylets. Stylets were dehydrated in ethanol and infiltrated with a low-viscosity resin. Subsequent polymerization of the resin allowed the embedded stylet to be ground and polished to reveal the stylet microstructure. This comprised increments that are probably suitable for age estimation. The technique was developed using stylets of Octopus vulgaris and Eledone cirrhosa. Increments were composed of light and dark bands and were clearly defined at ×400 and at ×625 magnifications. The number of increments ranged from 189 to 399. The stylets of a deep-sea species (Bathypolypus sponsalis) and an Antarctic species (Megaleledone setebos) were also examined. Each appeared to have growth increments, despite the perception that the environments they inhabited may not provide daily cues. Using the technique developed, the pre-hatch nucleus was seldom well defined, as reported for O. pallidus, stylets of which were prepared using a non-permanent method. Reasons for this are discussed. The microstructure clarity revealed is probably associated with the ultra-low viscosity of the resin used. [ABSTRACT FROM PUBLISHER]

Effects of river discharge on growth of redbreast sunfish Lepomis auritus were investigated in nine rivers in Georgia, U.S.A. Fish were aged and annular total length increments ( LTinc) estimated from measurements from sectioned sagittal otoliths using the generalized regression model that held for the effects of decreasing LTinc from annual age ( X): LTinc= bo− b1( X) ± bi( D), where bo, b1 and bi were the regression coefficients for the intercept and slopes and D, discharge, was either a single or multiple measurements of annular or seasonal flow volume or variation in flow volume. For eight of nine rivers, higher or greater variation in flows from April to June was associated with greater L. auritus growth; in the last river, higher flows from January to March were associated with greater fish growth. Across all rivers, L. auritus growth increments were 22, 45 and 36% greater in a wet year v. a dry year at ages 1, 2 and 3 years, respectively. Based on the results of this study, increasing water withdrawals by an additional 30% in five Georgia rivers would reduce the predicted number of L. auritus recruiting to 203 mm (angler preferred size) by 19–62%. [ABSTRACT FROM AUTHOR]

Abstract: Topographical relationships between the mineral and organic components are important to understand the process involved in biomineralisation. We examined nanostructural features of cod (Gadus morhua) otoliths using atomic force microscope (AFM). Acicular aragonitic fibres that form primary increments observed in scanning electron or light microscopy were composed of lamellae, themselves being composite arrangements of round granules (diameter<50nm) surrounded by an organic (?) cortex. The lamellae presented a banding pattern, which might correspond to a growth period of about 15min. Cod otolith granules were similar in size, shape and arrangement to that previously reported for another fish species. The existence of smallest otolith organization units is suggested since granules are themselves composite. Finally, the intra-daily growth rhythm makes it possible to consider very high-resolution biological and environmental reconstructions in the future. [Copyright &y& Elsevier]

Age and growth of alfonsinoBeryx splendens(Lowe) were studied using counts of presumed daily incremental growth rings on the transverse section of otoliths of fish collected from the Kanto District, central Japan. Microstructural growth increments were observed from the core to the outermost margin of the broadest of approximately 50 branches formed on the surface of an otolith. Of 98 otoliths examined, 46 were readable. The number of increments and fish lengths ranged from 448 (218 mm fork length[FL]) to 3701 (411 mm FL). The ages of these fish were estimated to be 1 year, 2 months and 10 years, 2 months, respectively, assuming that an increment was formed daily. The von Bertalanffy growth equation combined for males and females was expressed as follows:L t = 542{1 − exp [−0.133(t + 2.00)]}, whereL t is fork length (mm) at yearly aget. The results of the present study were compared with those of other researchers who had studied alfonsino from central Japan. [ABSTRACT FROM AUTHOR]

Abstract 1 During 1968–74, an outbreak of the European spruce sawfly Gilpinia hercyniae , defoliated many stands of Sitka spruce in commercial forests in mid-Wales. The needle trace method was used to determine retrospectively the temporal pattern and intensity of defoliation in a stand of Sitka spruce in Hafren Forest that had been damaged severely at the time of the sawfly outbreak. 2 An initial calibration experiment, designed to test the reliability of the needle trace method when applied to Sitka spruce, indicated that artificially induced defoliation of up to 75% was detected by the technique with an accuracy of ±7%. Higher rates of defoliation were underestimated by up to 17%. 3 For the main sample of trees, the needle trace method demonstrated that retention of needle sets (average needle retention) was reduced by up to 33–38% over a 10-year period coincident with the G. hercyniae outbreak and the years immediately afterward when the canopy was recovering. 4 Analysis of needle loss within separate needle cohorts and age-classes revealed that 1-year-old needles were the most severely defoliated. The density of 1-year-old needles was reduced by 51–78% in 1970–73. 5 Defoliation at the time of the G. hercyniae outbreak was associated with reductions in annual height, radial, and volume increments of 24–49%, 30–59% and 32–56%, respectively. Radial and volume increments suffered their greatest reductions 1 year later than height increments. 6 The study demonstrates that the needle trace method can be applied successfully to Sitka spruce to quantify defoliation caused by an insect outbreak occurring many years previously, and that the technique can provide data on needle loss that is valuable for interpreting reductions in tree growth. [ABSTRACT FROM AUTHOR]

The otolith microstructure and microchemistry of a tropical eel, Anguilla marmorata , were examined in glass eels collected from Taiwanese and Japanese coasts. Ages at metamorphosis (onset of metamorphosis) and recruitment, respectively, were 114 ± 13.8 (mean ± SD) days and 144 ± 15.7 days in Taiwanese stock, and 123 ± 13.9 days and 154 ± 17.3 days in Japanese stock. No significant differences were found in ages between the two stocks. The duration of metamorphosis estimated from otolith microstructure was 10–24 days, which is the same in the different stocks. For both stocks examined, close linear relationships were found between ages at metamorphosis and recruitment, suggesting that individuals that metamorphosed earlier were recruited to the coasts at a younger age. [ABSTRACT FROM AUTHOR]

Coralline algae that form rhodoliths are widespread globally and their skeletal growth patterns have been used as (paleo-) environmental proxies in a variety of studies. However, growth interruptions (hiati) within their calcareous skeletons are regarded as problematic in this context. Here we investigated how hiati in the growth of Arctic rhodoliths from the Svalbard archipelago correspond to their environment and morphology. Using X-ray micro-computed tomography and stepwise model selections, we found that rhodoliths from deeper waters are subject to more frequent hiatus formation. In addition, rhodoliths with a higher sphericity (i.e., roundness) are less often affected by such growth interruptions. We conclude that these correlations are mainly regulated by hydrodynamics, because, in deeper waters, rhodoliths are not turned frequently enough to prevent a dieback of coralline algal thalli forming on the underside of the rhodolith. In this coherence, spheroidal rhodoliths are turned more easily, therefore shortening the amount of time between turnover events. Moreover, the incidence of light is more advantageous in shallower waters where rhodoliths exhibit a greater share of their surface to diffused ambient light, thus enabling thallus growth also on the down-facing surface of the rhodoliths. In consequence, information on the frequency of hiatus formation combined with rhodolith morphology might serve as a valuable proxy for (paleo-)environmental reconstructions in respect to light availability and the hydrodynamic regime. [ABSTRACT FROM AUTHOR]

• Summary of the 5th International Sclerochronology Conference (Split, Croatia). • New research applying sclerochronology to the analysis of fish otoliths. • Research on bivalves combines growth increment analysis and shell geochemistry. • Frames fundamental research questions in sclerochronology. [ABSTRACT FROM AUTHOR]

This paper provides the first morphological and chemical description of the stylets (vestigial shell) of Enteroctopus megalocyathus, a large, commercially and ecologically important benthic species that is fished along the southern coasts of Argentina and Chile. The stylets are thin, semi-transparent curved structures embedded in the muscular tissue of the dorso-lateral regions of the mantle, and placed inside an epithelial sac. Rostral and post-rostral parts and a bend could be distinguished. Differences in the curvature of the post-rostral parts allow the discrimination of left and right stylets. In recent years these structures have received attention because of their potential use as a tool for age determination, based on interior growth rings. The elemental composition inside stylets can also assist in reconstructing environmental histories, and in determining dispersal and population structure. The length of the different parts and the maximum diameter at the bend were measured and compared between sexes and between left and right stylets. Transverse cuts were used to describe histological structures, the nucleus and the white core that surrounds it, and growth increments. Constituent chemical elements were analysed with a scanning electron microscope equipped with an X-ray energy-scattering microanalyzer. No significant differences between sexes were detected in the relative length of the post-rostral and rostral parts of the stylets. These relative lengths could, however, be of taxonomic value at the generic level. Two types of concentric increments were observed; the embryonic nucleus of the stylets was amorphous and did not present growth increments. The distribution of chemical elements in the stylets is also described. [ABSTRACT FROM AUTHOR]