Helper contributions to reproductive success in the splendid fairy-wren (Malurus splendens)

Summary In Malurus splendens, helpers were present in 65% of 226 group-years with at least one helper female in 37% of group-years. Most females helped for only one year, while many males did so for at least two years. Most were offspring of one or both present breeders, and in 53% of helper-years, helped both parents. For 159 helpers of known age and parentage, the mean coefficient of relatedness to the offspring was 0.47. Novice females with or without helpers produced fewer fledglings per season than females with one year breeding experience and the same level of help. Helpers did not affect production of fledglings per year by females with one year of experience. Females with two or more years experience and at least two helpers produced more fledglings than equivalent birds with one or no helpers. Experience and helpers have little effect on production of fledglings per nest but they lead to more females renesting after a first brood has been raised. Fewer than 20% of novices renest after fledging one brood, while for females with at least two years experience, the percent renesting after success is 40% with no help, 56% with one helper and 69% with 2 or more helpers. Experienced females begin their first clutch earlier than novices, and helpers reduce the time to renest after success from 66 days for an experienced female with no helpers to 50 days for females with at least two years experience and two or more helpers. Breeding females with helpers survive better (76%) than those with no helpers (55%), and helpers thus gain future indirect fitness. Despite their close relatedness to breeders and offspring, in only 19% of group-years did helpers increase their indirect fitness from an increase in productivity.     

Assessing the environmental fate of chemicals of emerging concern: a case study of the polybrominated diphenyl ethers

It is suggested that assessments of chemicals of emerging concern can be rationally structured around a multistage process in which fate and risk are evaluated with increasing accuracy as new data become available. An initial tentative and approximate assessment of fate and risk can identify key data gaps and justify and direct further investigations, which progressively improve the reliability of the assessment. This approach is demonstrated for a class of chemicals, the polybrominated diphenyl ethers (PBDEs), which is of increasing concern, but about which there is presently a lack of comprehensive data on properties, sources, fate and effects. Specifically, 20 PBDE congeners are investigated using the suggested approach and research needs are identified.     

A method to determine residue levels of persistent organochlorine pesticides in human milk from Indonesian women

A method has been developed for the analysis of organochlorine pesticides in human milk using solvent extraction, Florisil solid phase extraction clean-up and analysis by gas chromatography with an electron capture detector. The recovery of analytes from spiked milk samples was in the range 53 +/- 1% to 109 +/- 7% (n = 9). A small number of samples were obtained from women in a rural and an urban area of Indonesia and analysed using the developed method. The results are reported on a milk fat basis. All samples contained detectable residues of p,p'-DDT (urban mean 0.11 +/- 0.18 mgkg(-1) (n = 5), rural mean 0.07 +/- 0.03 mg kg(-1) (n = 5)) and p,p'-DDE (urban mean 0.05 +/- 0.04 m kg(-1) (n = 5), rural mean 0.76 +/- 1.46 mg kg(-1) (n = 5)). Residues of HCB, betaHCH, alpha-endosulfan and dieldrin were also detected in some samples. There was no significant difference (at the 95% confidence level) in levels of pesticides between urban and rural areas. The levels of organochlorine pesticides in milk from Indonesian women were lower than those reported from Indonesian women exposed to DDT through malaria eradication schemes and were similar to levels reported from UK and Japan.     

Prompt detection of alpha particles from 210Po: another clue to the origin of rock varnish?

Alpha particles have been measured coming from the surfaces of rocks covered with dark red-brown rock varnish, as well as rocks that appear to have little, if any, varnish. A pronounced peak at 5.3 MeV indicates the presence of 210Po, a short-lived natural-radioactive element. Surface activities for 33 samples range from 0.008 Bq/cm2 to 0.065 Bq/cm2. It is estimated that this nuclide is concentrated 10(11) times in these paper-thin coatings above its concentration in ground-level air. Gamma rays from the decay of 137Cs, a product of testing nuclear weapons some 50 years ago, were also detected. Analysis of samples of varnish stripped from the rock revealed traces of 239,240Pu and 238Pu. The presence of all of these isotopes strongly supports the theory that varnish films derive their building blocks from the atmosphere and, with time, all rocks in arid environments will become coated.     

Humanitarianism and Local Service Institutions in Angola

The role of local service institutions is not a major focus of current discourse on humanitarianism and complex emergencies. These institutions, in the few places where they are mentioned, are usually presented as either the seed of civil society and future democracy, or as pawns and components of the predatory economic, political and military élites. Few would deny that examples can be found which conform to both of these stereotypes. This simplistic representation of local institutions ignores the perspectives of the actors themselves — the nurses, extension agents, school teachers and others who actually staff most NGO-supported projects. The debate has focused on what ‘we’ should do; the moral dilemmas of aid agencies and their expatriate staff, inevitably leading to the question of whether or not humanitarian workers should stay or leave situations in which aid may be causing more harm than good. Without denying the fundamental importance of these issues, it is important to consider also how the discourse has unfortunately moved away from those humanitarian workers who have no such choice, since they live there. Current concerns about keeping humanitarian aid from feeding local political and military struggles may inadvertently and paradoxically serve to constrain room for man?uvre in the field, particularly among those individuals with the greatest tacit understanding of the predatory environment. There is a need to understand how actors in local service institutions make sense of their own situations, including the factors which frame their moral dilemmas and their day-to-day choices. By analysing the organisational processes within local service institutions, this study is intended to provoke consideration of how these individuals and their institutions may be effectively supported in complex emergencies through a focus on how they themselves deal with danger and complexity. It is suggested that there is a value in considering the lessons learnt in recent years about how service organisations in the North function in turbulent environments. This experience points to the importance of allowing workers the discretion to develop a relationship with their clients, and in so doing make sense of a confusing and ambivalent environment.     

“Philandering” — a mixed mating strategy in the splendid fairy-wren Malurus splendens

Summary In a population of the splendid fairy-wren Malurus splendens, we describe 202 intrusions by solitary adult males in full breeding plumage into the territories of conspecifics. Intrusions were not secretive and although silent they involved conspicuous flight above the vegetation and several characteristic display elements, including petal-carrying. Fifteen intrusions were observed in the 2 months before eggs were laid, but the rest occurred during the period of nest-building and egg-laying when the breeding female was presumed to be fertile, and were by males from adjacent territories. A high level of extra-pair fertilization has previously been determined in this species and we interpret many of these intrusions as attempts by males to obtain extra-pair copulations (EPC); we call this activity philandering. The costs and benefits of EPC for males and females are discussed and the promiscuous mating strategy of M. splendens is contrasted with the persistent social pairing in stable groups of this long-lived cooperatively breeding species.Offprint requests to: I. Rowley     

塔基图穆保护区——库克群岛的社区所属生态旅游明星

塔基图穆保护区 1996年创建于库克群岛的拉罗汤加岛 , 其目标是为了当前和未来生产者的利 益而对生物多样性实施保护 . 只有当地人民对其土地和资源拥有所有权 . 生态旅游将成为该 保护区的主要经济活动 . 在土地所有者同意和支持下 , 一个有指导的 “ 大自然漫步 “ 已经组 织起来 .