The hypothesis that shoaling fish can obtain information about a predator's approach from changes in the behaviour of other shoal members was tested in an experiment in which receiver minnows (Phoxinus phoxinus) behind a one‐way‐mirror could observe the reaction of transmitter minnows threatened by the stalk of a pike (Esox lucius) model. Although the receiver minnows were out of visual contact with the pike model they decreased their foraging behaviour and started hiding when the pike model came towards the feeding patch of the transmitter fish. The presence of skittering behaviour and inspection behaviour in the transmitter but not in the receiver fish suggests that individual confirmation of the predator does play a role in determining the nature of the anti‐predator response. Nevertheless there is clear evidence that receiver fish modify their own behaviour on the basis of information obtained from individuals which have seen a predator.

Purpose -The aim of this paper is to establish the extent to which life cycle costing is used as an early stage project evaluation tool by practitioners in the UK construction industry. The use of this evaluation tool has long been advocated by academics as a means of ensuring best value rather than lowest cost is a driver for business decisions related to potential built environment projects. Therefore there is a need to appraise its current uptake levels amongst built environment professionals and assess whether there are any barriers affecting its use in UK practice. Design/methodology/approach -Using a mixed methods approach, the authors present the findings from a survey of construction professionals located in the UK and the results from a series of follow up semi structured interviews designed to further explore the factors found to affect the use of life cycle costing in practice. Findings The study shows that life cycle costing is still not widely used by built environment professionals in the UK. The greatest inhibitor on the take up of the tool is the need of clients to budget on short term horizons. Other factors such as a lack awareness of the tool by practitioners and clients, unreliability of data into the long term and the overriding need for commercially driven projects to achieve maximum return on investment continue to inhibit the widespread adoption of life cycle costing as an early stage project evaluation tool. These findings have implications for the capability of the UK construction industry to deliver on its commitment to enhance the sustainability of the built environment. Originality/value -The paper offers insights into the current use of life cycle costing and the factors affecting its use in the UK.

Purpose -This paper assesses the selection and use, in practice, of appraisal frameworks regarding sustainability evaluation in UK social housing sector projects, which have been advocated by academics as a means of ensuring that business decisions related to potential built environment projects are driven by best value rather than lowest cost. It also seeks to identity the key features of sustainability as assessed at the project feasibility stage. The research context is housing regeneration projects undertaken by UK social housing providers.Design/methodology/approach -Using a quantitative approach, a survey was conducted of 481 built environment professionals working within the UK social housing sector, which generated an overall response rate of 24%.Research Limitations/implications -The methodological approach adopted failed to uncover fully the reasons why practitioners selected particular types of sustainability appraisal toolkits. Findings -The survey results revealed that few toolkits and models developed by academe to facilitate the development and evaluation of sustainability-led building projects have so far been adopted. The impact of organisational factors such as size, denomination, and maturity on the frameworks was analysed and, in general, no statistically significant relationship was found between organisational features and the models in use. The principal features of sustainability were found to be related to energy efficiency and asset life expectancy. These findings have implications for the UK construction industry's commitment to enhancing the built environment's sustainability and thereby stakeholder prosperity.Implications -This paper focuses on the current use of sustainability-led project appraisal models and the key features of sustainability whilst also providing directions for further research. It explores the adoption of sustainability-focused project evaluation practices in the UK social housing sector and outlines potential areas for further research, focused on developing a usable, holistic framework for evaluating sustainability during the early stages of project development to help to create a more sustainable built environment.

The study investigates the cause of the unusually high cost overruns experienced in highway project delivery in the tropical wetland setting of the Niger Delta region of Nigeria. This is in view of the extensive literature supporting the link between geology, the lack of geotechnical best practices and cost overruns. An empirical profiling of cost overrun research further reveals the predominance of mono-method studies based on survey methods, correlative analysis and archival data modelling techniques, all of which are underlain by positivism. The study argues that such positivist philosophies, although methodologically valid, cannot adequately explain and provide in-depth understanding of the contextual cost overrun drivers in highway organisations., Using a robust and thoughtfully designed mix of methods, the paper examines the contribution of geotechnical risks to cost overruns experienced in highway project, and demonstrates the relevance of context in cost overrun research. Cost overrun data from documentary sources for 61 completed highway projects in the Niger Delta are gathered and analysed, revealing an average value of 216%, with extreme cases, ranging up to 1925% of budgeted cost. To uncover the intrinsic contextual drivers, 16 interviews were conducted with participants from the three highway agencies in the region, responsible for the execution of the sampled highway projects. Adopting a geotechnical narrative, the data is thematically analysed, deductively and inductively. The results of the analysis identified that poor project governance, management and procurement practices, have inhibited the competent management of geotechnical risk, creating a propensity for extreme cost overruns on the highway projects. The study submits the phenomenon of cost overruns in public infrastructure projects is underlain by a complexity of contextual social constructs, which would have been overlooked in positivists studies. Cost overrun research therefore, needs to be contextually and numerically anchored.