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There is much anecdotal evidence that birds and their droppings are a major problem for the heritage profession. The purpose of this paper is to examine how serious heritage practitioners consider the bird impact to be.

An online survey was conducted of 59 Australian heritage professionals of between one and >20 year’s experience in the field.

Bird impacts were not considered of major concern to buildings. The longer experience a practitioner had, the less likely the impacts were considered an issue. Feral pigeons were deemed the most problematic, followed by cockatoos, starlings, swallows, seagulls, mynas, sparrows, cormorants, ibis, ducks and birds of prey. The professionals ranked common deterrent methods. The highest-ranking deterrents were bird netting and bird spikes, but they were only considered moderately effective. The costs of installation and maintenance, as well the ease of installation, were all deemed significantly less important than the physical impact, the aesthetic sympathy and the effectiveness of a deterrent method.

This study indicates that the impact of birds on buildings in Australia may be of less concern than previously thought, and may be driven by other factors (i.e. aesthetics, commercial companies) rather than actual effects.

This is first study of its kind that surveyed the experiences of a wide range of heritage practitioners.

Birds are implicated in spoiling and decay of buildings, especially through their droppings. Pigeons are considered the main culprits, and several studies have examined the effects and chemistry of accumulations of droppings without evidence to the exact origins of the source of the excreta. The paper aims to discuss these issues.

This study reviews and summarises the state of knowledge with regard to the impact of bird excreta on buildings. It experimentally assesses the acidity of fresh pigeon excreta with different diets and examines the development of the acidity of the excreta after voiding.

Feral pigeons in urban settings are known to be fed by a range of foods. Urban food scraps-derived diets produce more acidic excreta than more natural diets such as seeds. This is a first study of its kind to examine the impact of a bird’s diet on the pH and thus the resulting (potential) decay of masonry.

This study showed that from a management’s perspective, pigeons that subsist entirely on human provided foods will be depositing more initially acidic faeces. If faecal accumulation occurs; then, mould and other bacteria quickly alter the chemistry from acidic towards basic, but the damage may already be done.

This paper is the first study of its kind to examine the effects of fresh pigeon droppings of known origin and age once voided from the intestine. This allows the authors to assess the impact during the first few days.

Food‐borne infections due to campylobacter, shigella, salmonella and E. coli 0157 have shown a real increase three to four fold. Argues that between the mid‐1980s and 1992 the reasons are multifactorial and include unsafe farming methods, possibly a deterioration in water quality, problems associated with moist food processing and changes in social habitats.

In the UK poultrymeat has 46 per cent volume share of the primary meat market. In particular, chicken has seen dramatic growth over 40 years with 525 million broilers being consumed in 1993. Examines the issues relating to poultrymeat in terms of market status and growth, nutrition, muscle fibre characteristics and quality issues such as colour, texture, flavour and safety.

Three events of significance to this country took place in 1899 – the British Food Journal was launched, Australia retained the Ashes, and the Boer War hostilities commenced. If challenged on the order of their importance, cricketers and Empire‐builders may be excused their preference. However, looking at it purely from the standpoint of pro bono publico, the dispassionate observer must surely opt for the birth of a certain publication as being ultimately the most beneficial of the three.

Discusses the problems caused by pigeons in buildings and some common control techniques, and outlines a remedial programme. Briefly examines the natural history of the feral pigeon. Details the common control techniques of food reduction, poisons and narcotic baits, trapping, fertility control and removal of nest sites, shooting, predators, bird scarers, bird nets,sprung wires, spikes and repellent gels. Advocates the implementation of a specialized site investigation and suggests that control is unlikely to be achieved by the application of a single product or technique.

It is argued that food poisoning from salmonella‐infected food is serious and that there has been a dramatic and recent rise in the incidence of such poisoning which is accounted for by Salmonella enteritidis type 4, the source of which is eggs. The evidence for these claims is presented, the scale of the problem defined, and advice to the public given. Proposals for future controls in laying hens are suggested.

Heritability studies attempt to estimate the contribution of genes (vs. environments) to variation in phenotypes (or outcomes of interest) in a given population at a given time. This chapter scrutinizes heritability studies of adverse health phenotypes, emphasizing flaws that have become more glaring in light of recent advances in the life sciences and manifest most visibly in epigenetics.

Drawing on a diverse body of research and critical scholarship, this chapter examines the veracity of methodological and conceptual assumptions of heritability studies.

The chapter argues that heritability studies are futile for two reasons: (1) heritability studies suffer from serious methodological flaws with the overall effect of making estimates inaccurate and likely biased toward inflated heritability, and, more importantly (2) the conceptual (biological) model on which heritability studies depend – that of identifiably separate effects of genes versus the environment on phenotype variance – is unsound. As discussed, contemporary bioscientific work indicates that genes and environments are enmeshed in a complex (bidirectional, interactional), dynamic relationship that defies any attempt to demarcate separate contributions to phenotype variance. Thus, heritability studies attempt the biologically impossible. The emerging research on the importance of microbiota is also discussed, including how the commensal relationship between microbial and human cells further stymies heritability studies.

Understandably, few sociologists have the time or interest to be informed about the methodological and theoretical underpinnings of heritability studies or to keep pace with the incredible advances in genetics and epigenetics over the last several years. The present chapter aims to provide interested scholars with information about heritability and heritability estimates of adverse health outcomes in light of recent advances in the biosciences.

In 1990 we compiled an annotated bibliography of official state lists of endangered, threatened, and rare species. In gathering information for that bibliography, which appeared in Reference Services Review in Spring 1991, we found numerous unofficial sources of state lists, such as those developed by universities, institutes, and Natural Heritage Programs, which also provide valuable information on statuses of endangered, threatened, and rare species. A comprehensive search for unofficial lists results in this second bibliography.

Transmission routes that may contribute to the overall picture of campylobacteriosis and salmonellosis were explored by analysing the outside surfaces of 300 retail raw chicken packs for prevalence and enumeration of Campylobacter using a MPN/PCR assay and Salmonella using a MPN/visual immunoassay procedure. The surfaces of 72 packs (24.0 per cent) were externally contaminated with C. jejuni; 32 with counts of <6 MPN/pack and the remaining 40 with counts ranging from 6 to >2,200 MPN/pack. One whole chicken sample (0.3 per cent) was contaminated with S. Tennessee at <6 MPN/pack. The surfaces of offal packs were most contaminated with Campylobacter, with 18 per cent having a count of ≥100 MPN/pack in comparison with chicken portion packs (4/200, 2 per cent) and whole bird packs (1/50, 2 per cent). These observations suggest that packs could be a source of cross‐contamination, however, the contribution of this outer surface contamination pathway to foodborne illness can only be properly determined by development of a validated risk assessment model.