Visual fields in Flamingos: chick-feeding versus filter-feeding

In birds, the position and extent of the region of binocular vision appears to be determined by feeding ecology. Of prime importance is the degree to which vision is used for the precise control of bill position when pecking or lunging at prey. In birds that do not require such precision (probe and filter-feeders), the bill falls outside the binocular field, which extends above and behind the head, thus providing comprehensive visual coverage. Flamingos Phoenicopteridae are highly specialised filter-feeders. They employ a unique technique that does not require accurate bill positioning in which the inverted head is placed between the feet. Feeding flamingos often walk forwards with the head pointing “backwards”. Here we show that in Lesser Flamingos Phoeniconaias minor visual fields are in fact the same as those of birds that feed by precision pecking and that feeding flamingos are blind in the direction of their walking. We suggest that this is due to the requirement for accurate bill placement when flamingos feed their chicks with “crop-milk”, and possibly when building their nest. We propose that chick-feeding may be the ultimate determinant of visual field topography in birds, not feeding ecology.     

Ecologically based policy evaluation: application to ungulate management in New Zealand

Introduced ungulates, e.g., deer and Himalayan tahr, are variously considered as both pests and resources in New Zealand. Much ecological research has occurred into these species and into the ecosystems in which they live. Concurrently, much has been done to develop ‘management’ plans for these species. We reviewed ecological research relevant to these ungulates and developed ecologically relevant criteria to assess the extent to which these have been considered in these plans. Nine criteria were developed within four thematic areas: ecological principles, objectives and outcomes, adaptive management, and use of science information. Four planning documents were then evaluated. All four poorly or at best marginally considered fundamental ecological principles: only the Himalayan thar control plan scored well in terms of having objectives and outcomes that were clearly ecologically based; the thar plan was very strong in terms of its commitment to implementing adaptive management; and, in terms of using the best available science both the thar plan and the deer issues and options paper scored well. Overall, ecological science and principles have not played major roles in the development of some of these plans, probably because ultimately they reflect political choices that are difficult to support with the available ecological research.     

Variation in the levels of pregnancy- specific β-1-glycoprotein in maternal serum from chromosomally abnormal pregnancies

Human pregnancy-specific β-1-glycoprotein (SP1) was assayed retrospectively in stored maternal serum (MS) samples from 82 chromosomally abnormal pregnancies and 377 matched controls. The median MSSP1 concentration in 48 Down's syndrome pregnancies was significantly elevated at 1.17 multiples of the control median (MOM), and significantly reduced (0.5 MOM) in a group of eight cases of unbalanced translocations. There was no significant difference in median SP1 concentrations in cases of trisomy 18, trisomy 13, balanced translocations, or sex chromosome abnormalities. A comparison with human chorionic gonadotrophin results in the same series of samples indicates that SP1 is a less sensitive predictor of Down's syndrome pregnancies.     

Fetal akinesia/hypokinesia sequence: Prenatal diagnosis and intra-familial variability

Intrauterine fetal movement plays a key role in normal embryonic and fetal development (Moessinger, 1983). When movement is absent or decreased, abnormal development takes place which can be appreciated in newborns and/or fetuses with the fetal akinesia/ hypokinesia sequence. This sequence is caused by a number of heterogeneous entities which result in decreased fetal movements by the action of intrinsic or extrinsic factors. Prenatal diagnosis of the akinesia/hypokinesia sequence may be possible during the second trimester through the use of real-time ultrasonographic evaluation of fetal movement. We report a family with three consecutive affected pregnancies in which the prenatal presentation of this sequence varied. Based on the phenotypic findings of the three affected fetuses, we believe that although they superficially resemble those features found in the New–Laxova syndrome, they are probably affected with a distinctly different lethal form of akinesia/ hypokinesia transmitted in an autosomal recessive fashion.     

Quantification of elemental and total carbon in combustion particulate matter using thermal-oxidative analysis

The use of a two-step thermal-oxidative analysis (TOA) technique for quantification of the mass of total carbon (TC) and elemental carbon (EC) of turbine engine-borne particulate matter (PM) has been evaluated. This approach could be used in lieu of analysis methods which were developed to characterize diluted PM. This effort is of particular interest as turbine engine PM emissions typically have a higher EC content than ambient aerosols, and filter sample mass loadings can be significantly greater than recommended for existing analysis techniques. Analyses were performed under a pure oxygen environment using a two-step temperature profile; reference carbon and actual PM samples were used to identify appropriate analysis conditions. Thermal gravimetric analysis (TGA) methods were used to provide guidance on the nature of the carbon in several of the materials. This was necessary as a standard reference material does not exist for determination of the EC fraction in PM. The TGA also assisted in identifying an appropriate temperature range for the first-stage of the TOA method. Quantification of TC and EC for turbine engine PM samples using TOA was compared to results obtained using the NIOSH 5040 thermal-optical method. For first-stage TOA temperatures of 350°C and 400°C, excellent agreement between the techniques was observed in both the quantified TC and EC, supporting the viability for using TOA for analysis of turbine engine PM samples. A primary benefit of using TOA for these types of PM samples is that filters with relatively high PM mass loadings (sampled at the emission source) can be readily analyzed. In addition, an entire filter sample can be evaluated, as compared to the use of a filter punch sample for the NIOSH technique. While the feasibility of using a TOA method for engine PM samples has been demonstrated, future studies to estimate potential OC charring and oxidation of EC-type material may provide additional data to assess its impact on the OC/EC fractions for other carbon-type measurements.

Implications: This work presents results and procedures of an analytical method for the determination of total and elemental carbon, i.e., TC and EC present in combustion source particulate matter samples. In general, it is shown that the LECO TOA methodology is as reliable and comprehensive as NIOSH 5040 for determining TC and EC carbon types in particulate matter present in turbine emission sources, and should be considered as an alternative. Principles of the methodology, differences, and corresponding agreement with the standard NIOSH 5040 method and TGA analysis are discussed.     

Can chemical oxidation improve the permeability of infiltration basins?

The Rapid Infiltration and Extraction (RIX) facility, a soil aquifer treatment system, began taking secondary effluent from the City of San Bernardino, California, in 1996. The gradual decrease in the hydraulic conductivity of the infiltration basins at RIX has been attributed to the accumulation of organic matter in the surface sand. Periodic tillage of the surface sand to restore the permeability has mixed this organic matter to a depth of nearly 50 cm. We hypothesized that in situ chemical oxidation of the surface sand might improve the infiltration rate and increase the time between filling and drying cycles. The effect of organic matter oxidation on sand permeability was tested in laboratory sand columns treated with sodium hypochlorite, calcium hypochorite, and ozone gas. All oxidants significantly decreased the hydraulic conductivity of the surface sand. The loss in permeability was attributed to an increase in dispersed clay plus silt-sized particles that were released as a result of oxidation. This study suggests that ex situ sand-washing operations, currently being used to clean the sand, could be improved by the addition of oxidants to the wash water.     

Approximate bias of the estimated proportion in group testing

The maximum likelihood estimator for estimating proportions by group testing is biased. An expression for the approximate bias has been previously presented, which enables the creation of a less biased estimator by removing the term of \(O(n^{-1})\). However, in this previous work the term of \(O(n^{-2})\) was incorrectly derived. This note gives a correct derivation, and examines the relative contribution of the two terms.     

Trends in seabird breeding populations across the Great Barrier Reef

The Great Barrier Reef is an iconic ecosystem, known globally for its rich marine biodiversity that includes many thousands of tropical breeding seabirds. Despite indications of localized declines in some seabird species from as early as the mid-1990s, trends in seabird populations across the reef have never been quantified. With a long history of human impact and ongoing environmental change, seabirds are likely sentinels in this important ecosystem. Using 4 decades of monitoring data, we estimated site-specific trends for 9 seabird species from 32 islands and cays across the reef. Trends varied markedly among species and sites, but probable declines occurred at 45% of the 86 species-by-site combinations analyzed compared with increases at 14%. For 5 species, we combined site-specific trends into a multisite trend in scaled abundance, which revealed probable declines of Common Noddy (Anous stolidus), Sooty Tern (Onychoprion fuscatus), and Masked Booby (Sula dactylatra), but no long-term changes in the 2 most widely distributed species, Greater Crested Tern (Thalasseus bergii) and Brown Booby (Sula leucogaster). For Brown Booby, long-term stability largely resulted from increases at a single large colony on East Fairfax Island that offset declines at most other sites. Although growth of the Brown Booby population on East Fairfax points to the likely success of habitat restoration on the island, it also highlights a general vulnerability wherein large numbers of some species are concentrated at a small number of key sites. Identifying drivers of variation in population change across species and sites while ensuring long-term protection of key sites will be essential to securing the future of seabirds on the reef.     

Mainstreaming the social sciences in conservation

Despite broad recognition of the value of social sciences and increasingly vocal calls for better engagement with the human element of conservation, the conservation social sciences remain misunderstood and underutilized in practice. The conservation social sciences can provide unique and important contributions to society's understanding of the relationships between humans and nature and to improving conservation practice and outcomes. There are 4 barriers—ideological, institutional, knowledge, and capacity—to meaningful integration of the social sciences into conservation. We provide practical guidance on overcoming these barriers to mainstream the social sciences in conservation science, practice, and policy. Broadly, we recommend fostering knowledge on the scope and contributions of the social sciences to conservation, including social scientists from the inception of interdisciplinary research projects, incorporating social science research and insights during all stages of conservation planning and implementation, building social science capacity at all scales in conservation organizations and agencies, and promoting engagement with the social sciences in and through global conservation policy‐influencing organizations. Conservation social scientists, too, need to be willing to engage with natural science knowledge and to communicate insights and recommendations clearly. We urge the conservation community to move beyond superficial engagement with the conservation social sciences. A more inclusive and integrative conservation science—one that includes the natural and social sciences—will enable more ecologically effective and socially just conservation. Better collaboration among social scientists, natural scientists, practitioners, and policy makers will facilitate a renewed and more robust conservation. Mainstreaming the conservation social sciences will facilitate the uptake of the full range of insights and contributions from these fields into conservation policy and practice.