Characterization of the trade in manta and devil ray gill plates in China and South‐east Asia through trader surveys

1. Dried gill plates from manta and devil rays, some of the world's most biologically vulnerable fishes, have become a valued commodity in Asian dried‐seafood and traditional Chinese medicine markets. This trade is a primary driver of fisheries, which have led to declines in many mobulid populations.
2. With no reliable trade statistics and scarce data on mobulid fisheries, this study estimates the number and species of mobulids required to supply this trade, and investigates the consumers and suppliers involved and drivers of demand. Following preliminary market research, 525 trader surveys were conducted in Hong Kong, Singapore, Macau, Taiwan, and southern China.
3. Guangzhou, China was identified as the centre of the trade accounting for 99% of total estimated market volume of 60.5 tons of dried gill plates in 2011, increasing to 120.5 tons by 2013. The estimated number of mobulids converted from tons of gill plates more than doubled over the period to 130 000, comprising 96% devil rays, Mobula japanica, Mobula thurstoni, and Mobula tarapacana, and 4% Manta spp. By 2015 the Guangzhou market had declined sharply, reportedly due to conservation campaigns and government policies. However Hong Kong's gill plate sales increased dramatically between 2011 and 2015.
4. China, Indonesia, Vietnam, Sri Lanka, and India were reported most frequently as gill plate sources.
5. Vendors recommend gill plates (trade name pengyusai) for ailments ranging from acne to cancer and as a general health tonic. While pengyusai is a new addition to traditional Chinese medicine literature and is rarely prescribed by traditional medicine practitioners, it is readily available over the counter and aggressively marketed by vendors.
6. Working in concert with consumer demand reduction efforts, increased measures to restrict mobulid fisheries and trade are recommended to prevent further population declines of these highly vulnerable species.

Copyright © 2016 John Wiley & Sons, Ltd.     

Mental health in the veterinary profession: an individual or organisational focus?

The veterinary profession is experiencing a shortage of veterinarians, with attrition recognised as a substantial contributor. Research has also indicated increased levels of mental ill health and alarming suicide rates in practitioners. The primary aim of this study was to investigate the impact of eleven modifiable workplace factors on mental health outcomes, job appreciation and intention to leave the veterinary profession. The second aim was to ascertain whether workplace factors influence mental health outcomes after controlling for individual resilience. An online survey was completed by 73 practising Australian veterinarians. Unfavourable workplace factors correlated with adverse outcomes including depression, stress, reduced job appreciation and increased likelihood of leaving both the role and the profession. Workplace factors remained linked with the outcomes of job appreciation, depression and stress whilst controlling for practitioner resilience. Job appreciation was a significant predictor of intention to leave both the current role and the profession. Via multiple linear regression, two categories were identified as associated with improved psychological outcomes and job appreciation. These were workplace factors that represent breaks from workload and control or decision latitude in the workplace. Whilst resilience represents a key area for intervention, workplace factors potentially represent an easier-to-modify area for intervention.     

Growth performance and management of a mixed rainforest tree plantation

Monoculture plantations of Pinus, Eucalyptus and Acacia have beenestablished on rainforest lands throughout the world. However, this type of reforestation generally supplies low quality timber and contributes to landscape simplification. Alternatives to exotic monoculture plantations are now beginning to gain momentum with farmers and landholders attempting to establish a variety of rainforest trees in small plantations. When compared to the well studied commercial species, knowledge concerning the growth and management of many of these rainforest species is in its infancy. To help expand this limited knowledge base an experimental plantation of 16 rainforest tree species in a randomised design was established near Mt. Mee, in south-eastern Queensland, Australia. Changes in growth, form (based on stem straightness, branch size and branchiness), crown diameters and leaf area of each species were examined over 5 years. Patterns of height growth were also measured monthly for 31 months. Species in this trial could be separated into three groups based on their overall growth after 5 years and their growth patterns. Early successional status, low timber density, high maximum photosynthetic rates and large total leaf areas were generally correlated to rapid height growth. Several species (including Araucaria cunninghamii, Elaeocarpus grandis, Flindersia brayleyana, Grevillea robusta and Khaya nyasica) had above average form and growth, while all species in the trial had considerable potential to have increased productivity through tree selection. As canopy closure occurred at the site between years four and five, growth increments declined. To reduce stand competition a number of different thinning techniques could be employed. However, simple geometric or productivity based thinnings appear to be inappropriate management techniques for this mixed species stand as they would either remove many of the best performing trees or nearly half the species in the trial. Alternatively, a form based thinning would maintain the sites diversity, increase the average form of the plantation and provide some productivity benefits.     

Stomatal conductance of Acer rubrum ecotypes under varying soil and atmospheric water conditions: predicting stomatal responses with an abscisic acid-based model

A multiplicative model of stomatal conductance was developed and tested in two functionally distinct ecotypes of Acer rubrum L. (red maple). The model overcomes the main limitation of the commonly used Ball-Berry model (Ball et al. 1987) by accounting for stomatal behavior under soil drying conditions. We combined the Ball-Berry model with an integrated expression of abscisic acid (ABA)-based stomatal response to ABA concentration ([ABA]) in bulk leaf tissue (gfac), which coupled physiological changes at the leaf level with those in the root. The factor gfac = exp(-beta[ABA]L) incorporated the stomatal response to [ABA] into the Ball-Berry model by down regulating stomatal conductance (gs) in response to physiological changes in the root. The down regulation of gs is pertinent under conditions where soil drying may modify the delivery of chemical signals to leaf stomata. Model testing indicated that the multiplicative model was capable of predicting gs in red maple under wide ranges of soil and atmospheric conditions. Concordance correlation coefficients were high (between 0.59 and 0.94) for the tested ecotypes under three environmental conditions (atmospheric, rhizospheric and minimal stress). The study supported the use of gfac as a gas exchange function that controls water stress effects on gs and aids in the prediction of gs responses.     

Genetic variability and inheritance of aluminium tolerance as indicated by long root regrowth in lucerne (Medicago sativa L.)

The objective of this study was to quantify the genetic variability and determine the inheritance of Al tolerance in lucerne (or alfalfa) using a 4-parent diallel mating design. Regrowth root length (RRL), along with root length (RL) and total root length (TRL), was measured to indicate relative Al stress response using a hydroponic system in a 3 μM Al solution at pH 4.5. A diallel analysis indicated the significance of general combining ability (gca) variance for RRL but not the specific combining ability (sca) variance; the same result was obtained for TRL but not for RL. For both RRL and TRL, genetic variance appeared to be more important than the environmental variance. For RRL, a strong but non-significant correlation was indicated between parental performance and their gca effects; while mid-parent heterosis and/or over-dominance were detected, as associated with the expressed sca effects in several combinations. These results suggest the complex genetic nature and expression of Al tolerance in the 4-parent diallel crossing system tested. Al-tolerant parent, GAAT‘S’, was the most promising parent, conferring the highest gca effects for RRL as well as for other two characters. The existence of significant gca variance in RRL may also suggest the feasibility of improving Al tolerance through enhanced root regrowth using phenotypic recurrent mass selection to pyramid desirable Al-tolerant genes, focussing on parental lines and/or elite individual plants expressing long regrowth roots.     

Susceptibility of oat cultivars to groat discoloration: causes and remedies

Fungal isolations and fungicide efficacy trials were carried out to determine the possible causes of discoloration in oat groats and potential control measures. Alternaria species and Microdochium nivale were isolated from field samples, and Fusarium poae was found in glasshouse tests. Symptoms could be induced reliably in the field through the use of a mist irrigation system. The cultivar ‘Gerald’ was most resistant followed by ‘Jalna’. Cultivar ‘Image’ was most severely affected by discoloration and ‘Millennium’ was of intermediate susceptibility. None of the 28 fungicide‐timing combinations used in the field trials affected the occurrence of discoloured groats. It was concluded that the best strategy for minimizing risk of discoloured groats would be screening new cultivars or breeding material in mist‐irrigated field trials for genetically based resistance.     

Biomonitoring of atmospheric mercury in the vicinity of Kilauea,Hawaii

The release of mercury from volcanic eruptions on the Island of Hawaii has been well documented, but the dispersion characteristics have not previously been studied in detail. Samples of lichens were collected from around the island, and subsequent analysis showed levels ranging from < 8 to 59 µg Hg g^-1. The distribution of the accumulation of mercury clearly shows that there is a major input from the active eruption sites, but that this is significantly modified by variations in wind patterns. Superimposed on this regional distribution are two localised sites where the mercury accumulation is exceptionally high; this is attributed to the release of steam from the circulation of shallow ground waters.