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Recent large declines in house sparrow Passer domesticus L. populations in many European towns and cities have generated much speculation as to possible environmental causes, although empirical insights have been lacking. We measured reproductive success in a declining house sparrow population along an urbanization gradient in Leicester, England, and used mixed models to identify correlates of nesting success. A stochastic simulation approach was developed to estimate annual reproductive success when the number of breeding attempts was unknown, and to assess the sensitivity of reproductive success to variation in different environmental factors. During 2 out of 3 years, reproductive output was lower than the predicted threshold required for population stability. Years of inadequate reproduction were characterized by lower chick survival and body mass at fledging (a predictor of post-fledging survival). Factors associated with reduced reproductive output included low ambient temperatures, extremes of rainfall, high levels of vegetable material in the diet (all affecting chick survival and body mass), low aphid densities (an important component of chick diet) and high concentrations of air pollution from traffic (affecting chick body mass). Reproductive failure linked to inadequate invertebrate availability provides a plausible demographic mechanism accounting for declines in urban-suburban house sparrow populations. Increased traffic volume and vegetation removal are candidate causal factors in these declines although the mechanism underlying the former is unclear. Increasing densities of key invertebrate prey away from major roads should be an objective of conservation management aimed at urban-suburban house sparrows. This study illustrates the utility of mixed models for the analysis of individual sibling survival and of stochastic simulation for modelling reproductive success in multi-brooded animals.

Summary Cardiac disease is the primary cause of death in sickle cell disease (SCD). Right and left ventricular global longitudinal strain (RVGLS, LVGLS) are early markers of systolic dysfunction but are not well investigated among children with SCD. One hundred and forty‐three patients with HbSS or HbSβ0‐thalassaemia (median age 11 years, range 5–19 years) and 71 controls matched for age and sex were compared. RVGLS and LVGLS were measured and compared with conventional measures of echocardiography and markers of haemolysis and inflammation. RVGLS was higher in children with SCD than in controls (−25·72% ± 3·45% vs. −24·54% ± 2·41%, P = 0·005); LVGLS was not different. RVGLS decreased with older age in children with SCD (ρ = 0·338, P < 0·001) but not among controls. Decreased RVGLS was associated with increased left atrial end diastolic volume (ρ = 0·181, P = 0·04); RVGLS increased with cardiac output (r = −0·279, P = 0·01). RVGLS and LVGLS were not associated with disease‐modifying therapies, degree of anaemia or haemolysis markers. Elevated RVGLS may indicate an early RV compensatory mechanism in response to upstream myocardial insults and elevated cardiac output. Global longitudinal strain may serve as an early marker of altered myocardial function in children with SCD.

INTRODUCTION Spencer (1972, p.96) has pointed out that ringers can make valuable contributions to the study of ectoparasites during their ringing operations. The "Fair Isle" apparatus for collecting samples of ectoparasites from live birds was devised by Williamson (1954) and modified by the Ontario Bird Banding Association (1960). A bird is deloused by suspending it by its head in a glass vessel filled with chloroform vapour. The inhalation of vapour by the bird is prevented by fitting a cape of oiled silk over its head, then holding the hole in the cape firmly around the neck of the bird in one hand while stretching the fabric tightly across the mouth of the vessel with the other. Parasites collect in the bottom of the vessel. This procedure suffers from the disadvantage that each bird has to be supported by the collector. This renders it time-consuming and impracticable if large numbers of birds have to be deloused quickly in order to undertake, for example, studies on infestation periodicity or parasite population structure and life cycles. This paper describes a simple and safe method for the simultaneous delousing of batches of up to 20 live birds, and considers the statistical validity of the method for a range of host species.

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