New Zealand Farmer Narratives of the Benefits of Reduced Human Intervention During Lambing in Extensive Farming Systems

Easy-care or natural lambing pertainsto those sheep able to successfully lamb andrear at least one lamb without human assistancein a difficult environment. Such sheep may havea higher survival rate, lower lamb mortality,and require less shepherding at lambing thanother sheep breeds or strains. The farmer orshepherd account of easy-care lambing revealsseveral themes. Firstly, stock were bred tosurvive or suit local environments orconditions, particularly steep hill country inNew Zealand. This involved extensive culling ofundesirable dams, regardless of how well theymight perform in traits other than the abilityto survive and to produce live lambs atweaning. Sheep that did have problems wereoften assisted, recorded or marked and thenculled at an appropriate time; thus bothartificial (culling) and natural selection wereused. Secondly, natural selection enabled theimportant traits to be identified and they weresubsequently incorporated into artificialselection programs. Thirdly, the practice wasnecessitated by the impracticality ofsupervising lambing in difficult terrain andthe cost of skilled farm labor. Finally, it wasacknowledged that disturbance at lambingcreated problems and most importantly, theeasy-care approach reduced some of the problemstraditionally associated with lambing.Easy-care lambing systems thus aim to minimizesome of the detrimental effects associated withcarefully supervised lambing in someenvironments, by selecting sheep to suit boththat environment and modern farm management.They overcame pervasive influences our culturallegacy was exerting on the way we interact withanimals, and may have produced a system more inkeeping with the biology of the animal in anextensive environment.     

Seasonal variation in paediatric blood lead levels in Syracuse,NY, USA

Venous blood lead values for 2,633 children aged 0–4 years in Syracuse, New York, collected between 1 April 1992 and 31 March 1993 were summarised by census tract for study of geographic variability. A demographic exposure model is presented showing housing stock and SES (socioeconomic status) parameters as the most significant predictor variables. A seasonal trend in blood lead levels was observed with late summer values about 40% higher than late winter values for census tracts with the highest geometric mean PbB levels. Seasonal variation is compared with a biokinetic uptake model to examine hypotheses about temporal variations in soil and dust lead exposure patterns.     

RUNOFF SIMULATION USING RADAR RAINFALL DATA1

ABSTRACT: Rainfall data products generated with the national network of WSR-88D radars are an important new data source provided by the National Weather Service. Radar-based data include rainfall depth on an hourly basis for grid cells that are nominally 4 km square. The availability of such data enables application of improved techniques for rainfall-runoff simulation. A simple quasi-distributed approach that applies a linear runoff transform to grid-ded rainfall excess has been developed. The approach is an adaptation of the Clark conceptual runoff model, which employs translation and linear storage. Data development for, and results of, an initial application to a 4160 km² watershed in the Midwestern U.S. are illustrated.     

Costs of switching social groups for dominant and subordinate dark-eyed juncos (Junco hyemalis)

I quantified the costs of switching from a familiar to an unfamiliar flock for captive dark-eyed juncos (Junco h. hyemalis) by measuring several physiological and behavioral variables before and after flock switching. Birds that were initially dominant dropped in status in unfamiliar flocks, and experienced increased metabolic rates, while subordinate birds appeared to undergo less physiological change when switching flocks. This difference occurred despite a lack of any rank-related differences in the effects of joining a new flock on rates of aggression, weight change, access to food, or plasma corticosterone levels. These results suggest that for dominant, but not subordinate, individuals there is a measurable metabolic cost to joining a new social group, even in the absence of adverse factors such as food limitation. Dominant individuals may be less likely than subordinates to leave familiar flocks because of their higher metabolic costs when joining a new social group.     

Investigating potential for effects of environmental endocrine disrupters on wild populations of amphibians in UK and Japan: status of historical databases and review of methods.

Concern over global declines among amphibians has resulted in increased interest in the effects of environmental contaminants on amphibian populations, and more recently, this has stimulated research on the potential adverse effects of environmental endocrine disrupters in amphibians. Laboratory studies of the effects of single chemicals on endocrine-relevant endpoints in amphibian, mainly anuran, models are valuable in characterizing sensitivity at the individual level and may yield useful bioassays for screening chemicals for endocrine toxicity (for example, thyroid disrupting activity). Nevertheless, in the UK and Japan as in many other countries, it has yet to be demonstrated unequivocally that the exposure of native amphibians to endocrine disrupting environmental contaminants results in adverse effects at the population level. Assessing the potential of such effects is likely to require an ecoepidemiological approach to investigate associations between predicted or actual exposure of amphibians to (endocrine disrupting) environmental contaminants and biologically meaningful responses at the population level. In turn, this demands recent but relatively long-term population trend data. We review two potential sources of such data for widespread UK anurans that could be used in such investigations: records for common frogs and common toads in several databases maintained by the Biological Records Centre (UK Government Centre for Ecology and Hydrology), and adult toad count data from 'Toads on Roads' schemes registered with the UK wildlife charity 'Froglife'. There were little abundance data in the BRC databases that could be used for this purpose, while count data from the Toads on Roads schemes is potentially confounded by the effects of local topology on the detection probabilities and operation of nonchemical anthropogenic stressors. For Japan, local and regional surveys of amphibians and national ecological censuses gathering amphibian data were reviewed to compile survey methodologies and these were compared with methods used in the UK and other countries. Substantial consensus exists in amphibian survey methodologies and this should be exploited in the initiation of coordinated monitoring programs for widespread and common anuran amphibians in Japan and the UK to generate long-term robust and standardized population trend data. Such data would support comparative ecoepidemiological assessments of the impact of environmental endocrine disrupters in these two cooperating countries.     

Twin-twin transfusion syndrome recipient with arterial calcification and heterozygous variant in ABCC6: Evidence of a gene-environment interaction?

We report a case of a twin-twin transfusion syndrome (TTTS) recipient who, after successful fetoscopic surgery, developed a large pericardial effusion and calcifications of the aorta and main pulmonary artery. The donor fetus never had cardiac strain and never developed cardiac calcifications. A heterozygous likely pathogenic variant in ABCC6 (c.2018T > C, p.Leu673Pro) was identified in the recipient twin. While TTTS recipient twins are at risk of arterial calcifications and right heart failure secondary to the disease, calcifications of the great vessels are also observed in generalized arterial calcification of infancy, a Mendelian genetic disorder with associated biallelic pathogenic variations in ABCC6 or ENPP1, which can result in significant pediatric morbidity or mortality. The recipient twin in this case had some degree of cardiac strain prior to TTTS surgery; however, the progressive calcification of the aorta and pulmonary trunk occurred weeks after TTTS resolution. This case raises the possibility of a gene-environment interaction and emphasizes the need for genetic evaluation in the setting of TTTS and calcifications.     

Land cover changes reduce net primary production in tropical coastal peatlands of West Kalimantan,Indonesia

Mitigation and Adaptation Strategies for Global Change - Tropical peat swamp forests are carbon-rich ecosystems that have been threatened by high rates of land use change (LUC). Despite the...     

Long‐Term Trends of Specific Conductance in Waters Discharged by Coal‐Mine Valley Fills in Central Appalachia,USA

Anthropogenic salinization of freshwaters is a global concern. Coal surface mining causes release of dissolved sulfate, bicarbonate, calcium, magnesium, and other ions to surface waters in central Appalachia, USA, through practices that include mine rock disposal in valley fills (VFs). This region's surface waters naturally have low salinity, with specific conductance (SC, a salinity indicator) generally <200 μS/cm, and aquatic impacts have been found when SC exceeds the 300 to 500 μS/cm range. We analyzed SC in waters emerging from 137 VFs over periods of 1 to 23 years. Mean SCs for these VFs ranged from 227 to 2,866 μS/cm, generally rose during and immediately following construction, but often declined during latter portions of longer monitoring records. Seventy‐four of 103 VFs with postconstruction data had SC trends that fit negative quadratic forms. Of the 16 revegetated VFs with at least five years of SC data past the quadratic maximum, the mean quadratic maximum was 1,464 (±696) μS/cm and the model projected time required to approach natural conditions (by declining to <500 μS/cm) was 19.6 (±6.6) years after VF construction initiation, indicating long‐lasting but not permanent aquatic impacts due to elevated (>500 μS/cm) SC.