Catriona A. Morrison

University of East Anglia | UEA · School of Biological Sciences

Capsule Early male arrival on the breeding grounds results in early pairing but not early nesting in Chiffchaffs Phylloscopus collybita, and Chiffchaffs can nest, fail, and re-nest before Willow Warblers Phylloscopus trochilus begin nesting. Aims To quantify the consequences of timing of arrival for the subsequent timing of pairing, nesting, and r...

Wildlife conservation policies directed at common and widespread, but declining, species are difficult to design and implement effectively, as multiple environmental changes are likely to contribute to population declines. Conservation actions ultimately aim to influence demographic rates, but targeting actions towards feasible improvements in thes...

In migratory birds, early arrival on breeding sites is typically associated with greater breeding success, but the mechanisms driving these benefits are rarely known. One mechanism through which greater breeding success among early arrivers can potentially be achieved is the increased time available for replacement clutches following nest loss. How...

Figure S1. The association between estimates of male and female recapture probability at the 34 CE sites (black line is the line of unity). Figure S2. Annual variation in the random effect of year included in models of adult annual survival of male (black circles) and female (open circles) willow warblers at CE sites. Appendix S1. jags code used...

Male‐biased sex ratios occur in many bird species, particularly in those with small or declining populations, but the causes of these skews and their consequences for local population demography are rarely known. Within‐species variation in sex ratios can help to identify the demographic and behavioural processes associated with such biases. Small...

Most studies of evolutionary responses to climate change have focused on phenological responses to warming, and provide only weak evidence for evolutionary adaptation. This could be because phenological changes are more weakly linked to fitness than more direct mechanisms of climate change impacts, such as selective mortality during extreme weather...

Additional methodology for regional integrated population models

Additional methodology for regional integrated population models

Reproduction through sex carries substantial costs, mainly because only half of sexual adults produce offspring. It has been theorized that these costs could be countered if sex allows sexual selection to clear the universal fitness constraint of mutation load. Under sexual selection, competition between (usually) males and mate choice by (usually)...

Capsule: Breeding Willow Warblers, Phylloscopus trochilus, in the UK have advanced in timing of breeding but with little impact on overall productivity. Aims: To quantify the impact of shifts in timing of breeding on changes in Willow Warbler productivity across the UK. Methods: Using records of ∼7000 nests from the British Trust for Ornithology Ne...

Warmer temperatures resulting from climate change have led to predictions that the duration of the breeding season of many temperate bird species may be changing. However, the extent to which breeding seasons can be altered will also depend on the degree of flexibility in processes occurring at other points in the annual cycle. In particular, plast...

Landscapes are becoming increasingly intensively managed resulting in greater anthropogenic disturbance of ecosystems. Effective policies for conservation and management of wildlife populations will require a mechanistic understanding of the processes underlying the population responses to these changes. Detailed demographic studies are often of in...

Capsule Seasonal variation in garden House Sparrow numbers provides a tool to examine overall annual productivity, measuring the combined success of multiple breeding attempts and post-fledging survival.Aims To develop a metric to use British Trust for Ornithology (BTO) Garden BirdWatch (GBW) data to measure annual productivity in House Sparrows ac...

Aim: Recent, rapid population declines in many Afro-Palaearctic migratory bird species have focussed attention on changing conditions within Africa. However, processes influencing population change can operate throughout the annual cycle and throughout migratory ranges. Here, we explore the evidence for impacts of breeding and non-breeding conditio...

Capsule Stable isotope composition of feathers grown in Africa indicates that Willow Warblers, Phylloscopus trochilus, breeding in areas of Britain experiencing different population trends may vary in their distribution, timing of moult and/or use of prey resources during the non-breeding season. Aims To compare stable isotope ratios of feathers of...

The efficacy of seal rehabilitation is examined in a postrelease study of dive ability in harbor seal pups (Phoca vitulina) in the Wash, United Kingdom. Six rehabilitated seals were fitted with Sea Mammal Research Unit (SMRU) Argos Satellite Relay Data Logger tags and their individual dive behavior was monitored for an average of 122 d. The upper 9...

Aim  Over the past three decades, evidence has been growing that many Afro-Palaearctic migratory bird populations have suffered sustained and severe declines. As causes of these declines exist across both the breeding and non-breeding season, identifying potential drivers of population change is complex. In order to explore the roles of changes in...