Role of density in aggregation patterns and synchronization of spawning in the hermaphroditic scallop Pecten fumatus

In broadcast spawners, low densities and poor spawning synchronization can reduce fertilization success. In wild populations, individuals in close proximity tend to spawn more synchronously than those further apart, suggesting that low spawner densities may reduce gamete production by lessening the efficacy of pheromone signalling. This study assessed the role of adult density in aggregation patterns and spawning synchronization in a semi-sessile, hermaphroditic scallop, Pecten fumatus. The study was carried out in Great Bay, Tasmania, Australia (147.335 W, 43.220 S) in 2010–2012 by assessing (1) the relationship between density, small-scale aggregation patterns and nearest neighbour distance (NND), (2) the temporal pattern of spawning synchronization, and (3) the effect of site density and conspecific proximity on the probability of spawning. Densities observed in the field ranged from 1.455 to 0.021 ind m^?2. Sites with lower densities had less small-scale aggregation and greater NNDs. Patterns of small-scale aggregation and NNDs in P. fumatus were comparable to those observed in a gonochoristic species. Spawning synchronization was highly variable, ranging between 3.5 and 59.8 % of individuals spawning. P. fumatus was more likely to engage in spawning activity when at greater densities and at closer proximity to conspecifics. This strongly suggests that lower densities in this scallop reduce not only the number of individuals contributing to the production of gametes, but also reduces the synchronization of spawning.     

Normalisation models for accounting for fat content in stable isotope measurements in salmonid muscle tissue

Stable isotope analysis is increasingly used in ecological studies. Because lipid content influences δ¹³C, lipids should be removed from lipid-rich samples before δ¹³C analysis. To account for differences in δ¹³C arising from differences in lipid content, relationships between lipid content, C:N ratio and Δδ¹³C with lipid removal can be used to normalise lipid content to uniform levels. We investigate these relationships for salmonid muscle and evaluate the suitability of previously published normalisation equations for these fish. Salmonids with a wide range of condition (muscle lipid content = 3–35% of dry weight) were considered. There were no consistent relationships between lipid content or C:N ratio and Δδ¹⁵N. There were linear relationships between C:N ratio and lipid content (L = −16.53 + 6.27 × C:N); C:N ratio and Δδ¹³C (Δδ¹³C = −1.87 + 0.65 × C:N); and lipid content and Δδ¹³C (Δδ¹³C = 0.01 + 0.10 × L), which should be used on salmonid stable isotope studies.     

对太平洋岛屿的全球国际水域评估:跨界、水资源短缺和沿海渔业问题

跨界、水资源短缺和渔场问题以近期完成的太平洋岛屿全球国际水域评估(GIWA)结果为基础进行了讨论.太平洋岛屿水域面积3000万km2,占全球海洋面积的大约12%,在地理、人口和发展等方面具有多样性.全球性变化,尤其是海平面上升和海面温度的提高,是最主要的跨界关注的问题,因为它影响着生活的方方面面.水资源短缺和不可持续发展的海洋渔业问题也是讨论的议题,因为这些问题在可预见的将来会主宰整个地区,在此以斐济、基里巴斯、汤加的例子加以说明.社会经济因素,例如人口快速增长、城市化、传统生活方式的解体以及现金经济的发展,加剧了环境问题.本文提出了有助于解决这些问题的政策方案.     

Effects of Residential Development on Forest-Dwelling Neotropical Migrant Songbirds

Many bird species are in local or regional decline because of habitat loss or degradation. We attempted to disentangle the effects of residential development from the effects of forest size on forest-bird communities, with particular emphasis on Neotropical migrant species. Two variables were examined for their influence on avian diversity and abundance: forest size and the number of houses outside a forest within 100 m of the edge. We found that Neotropical migrants consistently increased in number and abundance as forest size increased. Of greater interest, we found that the number of houses surrounding a forest severely undermined its suitability for Neotropical migrants. Neotropical migrants consistently decreased in diversity and abundance as the level of adjacent development increased, regardless of forest size. The effects of development were striking: 4-ha woodlots without any nearby houses had on average a richer, more abundant Neotropical community than did 25-ha urban woodlots. No predictable pattern of change concerning development or forest size was observed for short-distance migrants or permanent residents. Current planning regulations generally permit housing right up to forest edges. This practice may prevent protection of ecological features within the forest. Threshold distances for housing developments around forests need to be determined to prevent or minimize adverse effects on features and functions within the forests.     

Polygyny in the great reed warbler,Acrocephalus arundinaceus: a possible case of deception

Summary Polygyny was studied for 1 year in a great reed warbler population breeding in southern Germany. Data on various parameters of male and territory characteristics were collected and subjected to multivariate statistical analysis in order to assess their relative importance in female choice. Differences in territory characteristics appeared to be more important (Tab. 1), but there was a strong correlation between male and territory characteristics (Fig. 2, 3). Although the evolutionary advantages of polygyny to males are obvious (Fig. 5), those to females are far from clear. Models based upon the polygyny threshold and sexy son hypotheses predict that females should gain evolutionary advantage in either the short or long-term. Our data did not confirm such predictions, and secondary females showed greatly reduced breeding success (Fig. 4). If females were able to assess the status of mated males, they should instead select unmated males. Great reed warblers are a migrant species with a short breeding cycle in which the male plays relatively little part. They defend large territories in reed beds where visibility is reduced. These factors may permit males to practice a form of deception, by moving and attracting a second female who has little chance to assess that he is already mated.     

Public Response to Media Coverage of Animal Cruelty

Activists’ investigations of animal cruelty expose the public to suffering that they may otherwise be unaware of, via an increasingly broad-ranging media. This may result in ethical dilemmas and a wide range of emotions and reactions. Our hypothesis was that media broadcasts of cruelty to cattle in Indonesian abattoirs would result in an emotional response by the public that would drive their actions towards live animal export. A survey of the public in Australia was undertaken to investigate their reactions and responses to. The most common immediate reaction was feeling pity for the cattle. Women were more likely than men to feel sad or angry. Most people discussed the media coverage with others afterwards but fewer than 10 % contacted politicians or wrote to newspapers. We conclude that the public were emotionally affected by the media coverage of cruelty to cattle but that this did not translate into significant behavioral change. We recommend that future broadcasts of animal cruelty should advise the public of contact details for counseling and that mental health support contacts, and information should be included on the websites of animal advocacy groups to acknowledge the disturbing effect animal cruelty exposes can have on the public.     

Strengthening the link between climate change adaptation and national development plans: lessons from the case of population in National Adaptation Programmes of Action (NAPAs)

As climate change adaptation planning moves beyond short term National Adaptation Programmes of Action (NAPA) to longer-term approaches, it is instructive to review the NAPA process and examine how well it was linked to national development planning. This paper reviews 41 NAPAs submitted by Least Developed Countries (LDCs) to the United Nations Framework Convention on Climate Change (UNFCCC), to assess the NAPA process in terms of NAPAs integration with countries’ national development strategies. The review outlines the actors involved in developing NAPAs and identifies the range of interventions included in countries’ priority adaptation actions. The paper uses the example of population as an issue related to both climate change and national development to assess how it is addressed as part of LDCs’ adaptation and national development agendas. The analysis shows that although countries recognize population pressure as an issue related to the ability to cope with climate change and as a factor hindering progress in meeting development goals, it is not well incorporated into either adaptation planning or in national development strategies. Among the 41 NAPAs, 37 link high and rapid population growth to climate change. Moreover, six NAPAs clearly state that slowing population growth or investments in reproductive health/family planning (RH/FP) should be considered among the country’s priority adaptation actions. Furthermore, two NAPAs actually propose a project with components of RH/FP among their priority adaptation interventions, although none of them has yet been funded. The paper points to structural issues that hamper better alignment between climate change adaptation and national development planning and offers recommendations for longer-term adaptation strategies that better meet the development needs of countries.     

Drivers of Coastal Shoreline Change: Case Study of Hon Dat Coast,Kien Giang,Vietnam

Coastal shorelines are naturally dynamic, shifting in response to coastal geomorphological processes. Globally, land use change associated with coastal urban development and growing human population pressures is accelerating coastal shoreline change. In southern Vietnam, coastal erosion currently is posing considerable risks to shoreline land use and coastal inhabitants. The aim of this paper is to quantify historical shoreline changes along the Hon Dat coast between 1995 and 2009, and to document the relationships between coastal mangrove composition, width and density, and rates of shoreline change. The generalized linear mixed-effects models were used to quantify the major biophysical and land-use factors influencing shoreline change rates. Most significant drivers of the rates of change are cutting of mangroves, the dominant mangrove genus, changes in adjacent shoreline land use, changes of shoreline land cover, and width of fringing mangroves. We suggest that a possible and inexpensive strategy for robust mangrove shoreline defense is direct mangrove planting to promote mangrove density with the presence of breakwater structures. In the shorter term, construction of coastal barriers such as fence-structured melaleuca poles in combination with mangrove restoration schemes could help retain coastal sediments and increase the elevation of the accretion zone, thereby helping to stabilize eroding fringe shorelines. It also is recommended that implementation of a system of payments for mangrove ecosystem services and the stronger regulation of mangrove cutting and unsustainable land-use change to strengthen the effectiveness of mangrove conservation programs and coastal land-use management.     

Trends in anecdotal fox sightings in Tasmania accounted for by psychological factors

There has been little evaluation of anecdotal sightings as a means to confirm new incursions of invasive species. This paper explores the potential for equivocal information communicated by the media to account for patterns of anecdotal reports. In 2001, it was widely reported that red foxes (Vulpes vulpes) had been deliberately released in the island state of Tasmania (Australia), although this claim was later revealed to be baseless. Regardless, by 2013 a total of 3153 anecdotal fox sightings had been reported by members of the public, which implied their distribution was wide. For each month in 2001–2003, we defined a monthly media index (MMI) of fox‐related media coverage, an index of their relative seasonal abundance (abundance), and a factor denoting claims of fox evidence (claimed evidence) regardless of its evidentiary quality. We fitted a generalized linear model with Poisson error for monthly totals of anecdotal sightings with factors of year and claimed evidence and covariates of MMI, abundance, and hours of darkness. The collective effect of psychological factors (MMI, claimed evidence, and year) relative to biophysical factors (photoperiod and abundance) was highly significant (χ² = 122.1, df = 6, p < 0.0001), whereas anticipated changes in abundance had no significant influence on reported sightings (p = 0.15). An annual index of fox media from 2001 to 2010 was strongly associated with the yearly tally of anecdotal sightings (p = 0.018). The odds ratio of sightings ranked as reliable by the fox eradication program in any year decreased exponentially at a rate of 0.00643 as the total number of sightings increased (p < 0.0001) and was indicative of an observer‐expectancy bias. Our results suggest anecdotal sightings are highly susceptible to cognitive biases and when used to qualify and quantify species presence can contribute to flawed risk assessments.