Nicola Weber

• BSc (Hons), MSc, PhD
• Senior Lecturer at University of Exeter

The establishment of large-scale marine protected areas (LSMPAs) has emerged as one of the defining trends in ocean conservation over recent decades. To assess the potential benefits of such designations, it is necessary to understand the nature of the threats that have been excluded. Here, we summarise over 25 years of historical catch and effort...

Seamounts have been likened to “oases” of life in the comparative deserts of the open ocean, often harbouring high densities of threatened and exploited pelagic top predators. However, few such aggregations have been studied in any detail and the mechanisms that sustain them are poorly understood. Here, we present the findings of an integrated stud...

The United Kingdom Overseas Territory of Montserrat supports modest but regionally important nesting populations of green and hawksbill turtles. However, knowledge of the spatial ecology and regional connectivity of these populations is limited. Here, we provide the first detailed description of the spatial distribution, migratory connectivity, and...

Successful embryonic development and offspring sex ratios of marine turtles are determined by thermal conditions experienced during incubation, rendering them potentially vulnerable to anthropogenic climate change. With the rate of projected temperature rises likely to outpace the adaptive capacity of long-lived species such as marine turtles, ther...

Seabirds are among the most threatened birds as a result of acute exposure to many anthropogenic threats. Their effective conservation requires a detailed understanding of how seabirds use marine habitats. Recently, one of the largest no-take marine reserves in the Atlantic was designated in tropical waters surrounding Ascension Island, on which th...

Significance Elucidating the mechanisms that regulate animal populations is a fundamental goal in ecology and is increasingly important at a time of unprecedented anthropogenic disturbance to ecosystems. Here, we present direct evidence of a phenomenon known as “Ashmole’s halo”: a zone of prey depletion that is hypothesized to form around aggregati...

Timing of activity can reveal an organism's efforts to optimize foraging either by minimizing energy loss through passive movement or by maximizing energetic gain through foraging. Here, we assess whether signals of either of these strategies are detectable in the timing of activity of daily, local movements by birds. We compare the similarities of...

Timing of activity can reveal an organism's efforts to optimize foraging either by minimizing energy loss through passive movement or by maximizing energetic gain through foraging. Here, we assess whether signals of either of these strategies are detectable in the timing of activity of daily, local movements by birds. We compare the similarities of...

The human-mediated spread of invasive, non-native species (INNS) is a major driver of biodiversity loss and habitat degradation worldwide, threatening ecosystems, food security and sustainable development goals. The impacts of INNS have been particularly acute on small islands due to a lack of ecosystem resilience, limited management capacity and t...

Ascension Island is a UK Overseas Territory in the tropical South Atlantic that supports regionally and globally important nesting populations of 11 seabird species. Its status as one of the most important warm-water seabird breeding stations in the world is probably linked to its isolated position close to a zone of elevated productivity driven by...

Adaptation to increasing temperatures may enable species to mitigate the long-term impacts of climate change. Sea turtles have temperature dependent sex determination (TSD) and variation in the thermal reaction norm, which influences offspring sex ratio, has been suggested as a potential adaptive mechanism to rising global temperatures. Here, we in...

In the face of accelerating ecological change to the world's oceans, seabirds are some of the best bio‐indicators of marine ecosystem function. However, unravelling ecological changes that pre‐date modern monitoring programmes remains challenging. Using stable isotope analysis of feathers and regurgitants collected from sooty terns (Onychoprion fus...

Population structure is critical to infectious disease transmission. As a result, theoretical and empirical contact network models of infectious disease spread are increasingly providing valuable insights into wildlife epidemiology. Analyzing an exceptionally detailed dataset on contact structure within a high‐density population of European badgers...

Knowing the spatial scales at which effective management can be implemented is fundamental for conservation planning. This is especially important for mobile species, which can be exposed to threats across large areas, but the space use requirements of different species can vary to an extent that might render some management approaches inefficient....

Knowing the spatial scales at which effective management can be implemented is fundamental for conservation planning. This is especially important for mobile species, which can be exposed to threats across large areas, but the space use requirements of different species can vary to an extent that might render some management approaches inefficient....

Detecting opportunities for between-species transmission of pathogens can be challenging, particularly if rare behaviours or environmental transmission are involved. We present a multilayer network framework to quantify transmission potential in multi-host systems, incorporating environmental transmission, by using empirical data on direct and indi...

Predators exploiting tropical pelagic waters characterised by low fluctuations in seasonal temperature and salinity may require different foraging strategies than predators that can rely on persistently productive marine features. Consistent individual differences in foraging strategies have been found in temperate seabirds, but it is unclear wheth...

Contact networks are fundamental to the transmission of infection and host sex often affects the acquisition and progression of infection. However, the epidemiological impacts of sex-related variation in animal contact networks have rarely been investigated. We test the hypothesis that sex-biases in infection are related to variation in multilayer...

Epinephelus adscensionis sampled from Ascension Island, South Atlantic Ocean, exhibits distinct life-history traits, including larger maximum size and size at sexual maturity than previous studies have demonstrated for this species in other locations. Otolith analysis yielded a maximum estimated age of 25 years, with calculated von Bertalanffy grow...

We present the first record of the Ascension Frigatebird (Fregata aquila) for the Americas by retrieving coordinates from an individual equipped with a satellite transmitting device. As part of a wider study on the spatial and behavioral ecology of this species, we tracked a single juvenile frigatebird that entered into Brazilian waters as defined...

Social interactions among hosts influence the persistence and spread of infectious pathogens. Daily and seasonal variation in the frequency and type of social interactions will play an important role in disease epidemiology and, alongside other factors, may have an influence on wider disease dynamics by causing seasonal forcing of infection, especi...

The growth of the chelae of mature males was examined in three gecarcinid land crabs — Johngarthia lagostoma on Ascension Island, Epigrapsus notatus on Taiwan, and E. politus on Moorea. Chelar dimorphism was found in each species, with a mixture of homochelous and heterochelous males. In J. lagostoma there was progressive polymorphism, with the het...

Recent studies have improved our understanding of nearshore marine ecosystems surrounding Ascension Island (central Atlantic Ocean), but little is known about Ascension's benthic environment beyond its shallow coastal waters. Here, we report the first detailed physical and biological examination of the seabed surrounding Ascension Island at 100–100...

Host social structure is fundamental to how infections spread and persist, and so the statistical modelling of static and dynamic social networks provides an invaluable tool to parameterise realistic epidemiological models. We present a practical guide to the application of network modelling frameworks for hypothesis testing related to social inter...

Contact networks, behavioral interactions, and shared use of space can all have important implications for the spread of disease in animals. Social networks enable the quantification of complex patterns of interactions; therefore, network analysis is becoming increasingly widespread in the study of infectious disease in animals, including wildlife....

Environmental specimens lining seawater blowholes of Whale Point, Ascension Island in the South Atlantic Ocean were collected (August 2012) and investigated by morphological and molecular techniques. Reported here, Acremonium stroudii (Ascomycota) sp. nov., a filamentous conidia-forming fungus, was the only fungus isolated from the samples collecte...

Camouflage is perhaps the most widespread anti-predator strategy in nature, found in numerous animal groups. A long-standing prediction is that individuals should have camouflage tuned to the visual backgrounds where they live. However, while several studies have demonstrated phenotype-environment associations, few have directly shown that this con...

Many animals reproduce in large aggregations, which can vary in size from dozens to millions of individuals across species, time and space. The size of breeding colonies is a complex trade-off between multiple costs and benefits to an individual’s fitness, but the mechanisms by which colony size affects fitness are still poorly understood. One impo...

Ascension Island in the South Atlantic Ocean is renowned for its globally-important nesting population of green turtles (Chelonia mydas) that has been the subject of long-term research. By comparison, very little is known about the apparently small population of hawksbill turtles (Eretmochelys imbricata) that have been recorded in its waters, thous...

Although many species of marine mega-vertebrates are threatened as a result of human activity, some populations are showing promising signs of recovery following decades of protection. In this study, we report on the status of the South Atlantic’s largest green turtle (Chelonia mydas) nesting aggregation at Ascension Island, 70 years after legal pr...

The stage at which land crabs of the Gecarcinidae recruit to land is examined, and discussed in relation to recruitment in other terrestrial crabs. New data are presented for species of Johngarthia, and published data on other species are re-examined and evaluated. The gecarcinids Gecarcinus and Johngarthia appear unique in that the megalops migrat...

Although disease hosts are classically assumed to interact randomly, infection is likely to spread across structured and dynamic contact networks. We used social network analyses to investigate contact patterns of group-living European badgers, Meles meles, which are an important wildlife reservoir of bovine tuberculosis (TB). We found that TB test...

SUMMARY Tuberculosis (TB) due to infection with Mycobacterium bovis is transmitted between cattle and badgers (Meles meles) in the UK and Ireland but it is unclear where or when transmission occurs. We investigated direct and indirect interactions between badgers and cattle using automated proximity loggers on animals and at badger latrines located...

Heterogeneities in behaviours of individuals may underpin important processes in evolutionary biology and ecology, including the spread of disease. Modelling approaches can sometimes fail to predict disease spread, which may partly be due to the number of unknown sources of variation in host behaviour. The European badger is a wildlife reservoir fo...

Knowledge of the way in which animals interact through social networks can help to address questions surrounding the ecological and evolutionary consequences of social organisation, and to understand and manage the spread of infectious diseases. Automated proximity loggers are increasingly being used to record interactions between animals, but the...

A guide to the use of the two Functions for which the R code is provided. (DOC)

R Code for the two Functions that can be used to filter and construct association matrices from data collected by proximity loggers. (R)

Tool use is so rare in the animal kingdom that its evolutionary origins cannot be traced with comparative analyses. Valuable insights can be gained from investigating the ecological context and adaptive significance of tool use under contemporary conditions, but obtaining robust observational data is challenging. We assayed individual-level tool-us...