Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
85
result(s) for
"Calvert, Anna"
Sort by:
Landscape Movements of Migratory Birds and Bats Reveal an Expanded Scale of Stopover
by
Thurber, Bethany G.
,
Taylor, Philip D.
,
Mills, Alex M.
in
Animal behavior
,
Animal breeding
,
Animal Migration
2011
Many species of birds and bats undertake seasonal migrations between breeding and over-wintering sites. En-route, migrants alternate periods of flight with time spent at stopover--the time and space where individuals rest and refuel for subsequent flights. We assessed the spatial scale of movements made by migrants during stopover by using an array of automated telemetry receivers with multiple antennae to track the daily location of individuals over a geographic area ~20 × 40 km. We tracked the movements of 322 individuals of seven migratory vertebrate species (5 passerines, 1 owl and 1 bat) during spring and fall migratory stopover on and adjacent to a large lake peninsula. Our results show that many individuals leaving their capture site relocate within the same landscape at some point during stopover, moving as much as 30 km distant from their site of initial capture. We show that many apparent nocturnal departures from stopover sites are not a resumption of migration in the strictest sense, but are instead relocations that represent continued stopover at a broader spatial scale.
Journal Article
Understanding the barriers and enablers to participation in vaccine trials in a pregnant population from diverse ethnic background in an inner-city UK hospital
by
Oshodi, Lolade
,
Vandrevala, Tushna
,
Eccleston, Emma
in
Adult
,
Beliefs, opinions and attitudes
,
Biology and Life Sciences
2024
Vaccination during pregnancy is an important healthcare intervention for safeguarding the health of the mother and their infants. Ethnic disparities in recruitment to vaccine research studies during pregnancy potentially contribute to health inequalities. The aim of the current study was to explore the barriers and enablers influencing the willingness of pregnant women from ethnic minority backgrounds to participate in vaccine research studies.
Semi-structured qualitative online interviews were conducted with 23 pregnant women from diverse ethnic backgrounds in the UK. Interviews were transcribed verbatim, and thematically analysed. Our findings suggest that participants perceived vaccines and vaccine research, in principle, to be beneficial to the individual and to society, and understood the value of vaccination in mitigating severity of disease and protecting the health of mothers and their infants. Apprehension over the safety of vaccination in pregnancy was common and reduced willingness to participate. For those that decided to participate in vaccine trials in pregnancy, this was seen as an act of solidarity, a way to contribute to a collective responsibility for the public health of the community. Personal and community connections and representation-seeing people from their own communities represented in in the recruitment process shapped decisions about vaccine trial participating. Trust and mistrust in health systems, shaped by past experiences of interacting with healthcare professionals were likely to inform whether they would consider participating. Practical considerations such as excessive time commitments related to study procedures, travel and organising childcare were barrier to participation. The level of invasiveness of trial procedures were also a concern, although increased monitoring during the trial was seen as a potential benefit, mitigating some safety concerns.
Our study reinforcing previously identified barriers to vaccine participation among pregnant women from diverse ethnic communities. This study underlines the need to develop tailored interventions that focus on fostering trust with the aid of community engagement to understand cultural contexts, establishing authentic representation, and address practical considerations, to contribute to enhancing vaccine trial participation in pregnancy in those from diverse ethnic communities.
Journal Article
A phase IV, multi-centre, randomized clinical trial comparing two pertussis-containing vaccines in pregnant women in England and vaccine responses in their infants
by
Southern, Jo
,
Matheson, Mary
,
Jones, Christine Elizabeth
in
Antibodies
,
Antibodies, Bacterial
,
Antigens
2021
Background
Pertussis vaccines containing three or five pertussis antigens are recommended in pregnancy in many countries, but no studies have compared the effect on infants’ antigen-specific immunoglobulin G (IgG) concentrations. The aim of this study was to compare anti-pertussis IgG responses following primary immunization in infants of mothers vaccinated with TdaP
5
-IPV (low dose diphtheria toxoid, tetanus toxoid, acellular pertussis [five antigens] and inactivated polio) or TdaP
3
-IPV in pregnancy (three pertussis antigens).
Methods
This multi-centre phase IV randomized clinical trial was conducted in a tertiary referral centre and primary care sites in England. Women were randomized to receive TdaP
5
-IPV (
n
= 77) or TdaP
3
-IPV (
n
= 77) at 28–32 gestational weeks. A non-randomized control group of 44 women who had not received a pertussis-containing vaccine in pregnancy and their 47 infants were enrolled post-partum.
Results
Following infant primary immunization, there was no difference in the geometric mean concentrations (GMCs) of anti-pertussis toxin, filamentous haemagglutinin or pertactin IgG between infants born to women vaccinated with TdaP
5
-IPV (
n
= 67) or TdaP
3
-IPV (
n
= 63). However, the GMC of anti-pertussis toxin IgG was lower in infants born to TdaP
5
-IPV- and TdaP
3
-IPV-vaccinated mothers compared to infants born to unvaccinated mothers (
n
= 45) (geometric mean ratio 0.71 [0.56–0.90] and 0.78 [0.61–0.98], respectively); by 13 months of age, this difference was no longer observed.
Conclusion
Blunting of anti-pertussis toxin IgG response following primary immunization occurs in infants born to women vaccinated with TdaP
5
-IPV and TdaP
3
-IPV, with no difference between maternal vaccines. The blunting effect had resolved by 13 months of age. These results may be helpful for countries considering which pertussis-containing vaccine to recommend for use in pregnancy.
Trial registration
ClinicalTrials.gov
,
NCT02145624
, registered 23 May 2014
Journal Article
Subpopulation contributions to a breeding metapopulation of migratory arctic herbivores: survival, fecundity and asymmetric dispersal
by
Drake, Kiel L.
,
Kellett, Dana K.
,
Calvert, Anna M.
in
Adults
,
Anser caerulescens
,
Anthropogenic factors
2022
Estimates of demographic parameters for lesser snow geese Anser caerulescens caerulescens have become critical to understand ecosystem change in northern Canada. Exponential increase in abundance has produced hyperdensities of these herbivores that can affect Arctic ecosystem stability through intense foraging. Increased and sustained marking of individually‐identifiable lesser snow geese over their breeding distribution now permits joint estimation of local vital rates and movement probabilities among widely scattered subpopulations. We used multi‐state models, including an unobservable state, with live captures from 5 subpopulations and dead recoveries to estimate annual probabilities of 1) survival, 2) capture, 3) reported mortality and 4) movement to other subpopulations, as well as derived estimates for probabilities of site fidelity and harvest. Our dataset included 144 719 captures of 139 177 lesser snow geese marked with metal legbands, from 2006 to 2015, of which 5542 were recaptured near breeding sites and 9709 were recovered dead in North America. The best model supported variation in survival by subpopulation and age, with additive effects of subpopulation, age and sex on movement probability. Male breeding dispersal was greater than by females, and juvenile geese were more likely to move than adults. Strong northeastward geographic asymmetry in the probability of breeding movement was consistent with an eastward shift in wintering distribution observed in hunter recoveries. Mean annual survival ranged from 0.79 to 0.94 for adults, and 0.16 to 0.47 for juvenile geese, with a strong negative relationship between regional adult and juvenile survival. Harvest probabilities were all ≤ 0.03 for adult and ≤ 0.06 for juvenile geese, suggesting little influence from direct anthropogenic exploitation. Metrics for subpopulation persistence and contributions of each to the metapopulation suggested declines in all but one subpopulation, and a declining Midcontinent population overall. Our study highlights the importance of all subpopulation demographic parameters as modulators of persistence at both local and range‐wide population dynamics.
Journal Article
Habitat loss accelerates for the endangered woodland caribou in western Canada
by
Hebblewhite, Mark
,
Venter, Oscar
,
DeMars, Craig
in
Anthropogenic factors
,
Caribou
,
Deceleration
2021
Habitat loss is often the ultimate cause of species endangerment and is also a leading factor inhibiting species recovery. For this reason, species‐at‐risk legislation, policies and plans typically focus on habitat conservation and restoration as mechanisms for recovery. To assess the effectiveness of these instruments in decelerating habitat loss, we evaluated spatiotemporal habitat changes for an iconic endangered species, woodland caribou (Rangifer tarandus caribou). We quantified changes in forest cover, a key proxy of caribou habitat, for all caribou subpopulations in Alberta and British Columbia, Canada. Despite efforts under federal and provincial recovery plans, and requirements listed under Canada's Species at Risk Act, caribou subpopulations lost twice as much habitat as they gained during a 12‐year period (2000–2012). Drivers of habitat loss varied by ecotype, with Boreal and Northern Mountain caribou affected most by forest fire and Southern Mountain caribou affected more by forest harvest. Our case study emphasizes critical gaps between recovery planning and habitat management actions, which are a core expectation under most species‐at‐risk legislation. Loss of caribou habitat from 2000 to 2018 has accelerated. Linear features within caribou ranges have also increased over time, particularly seismic lines within Boreal caribou ranges, and we estimated that only 5% of seismic lines have functionally regenerated. Our findings support the idea that short‐term recovery actions such as predator reductions and translocations will likely just delay caribou extinction in the absence of well‐considered habitat management. Given the magnitude of ongoing habitat change, it is clear that unless the cumulative impacts of land‐uses are effectively addressed through planning and management actions that consider anthropogenic and natural disturbances, we will fail to achieve self‐sustaining woodland caribou populations across much of North America.
Journal Article
Adult survival and annual movement patterns of common snipe in Iceland
by
Petrek, Scott W.
,
Petersen, Aevar
,
Thorstensen, Sverrir
in
Animal populations
,
Bird migration
,
Birds
2023
The common snipe (Gallinago gallinago) is a wader that breeds in subarctic regions from Iceland to Russia, and for which global populations are in decline. We studied snipe breeding in western Iceland between 1998 and 2020, locating nests and ringing birds annually. In 2019 and 2020, we deployed geolocators on nesting adults to estimate the timing of their annual migration and the location of overwintering areas. Birds moved principally between breeding locations in Iceland to wintering areas in Ireland, although some birds may winter farther north. We also found that apparent annual adult survival averaged 66%, but was higher in years with warmer, wetter winters. Given the similarity of our survival estimates to those from snipe elsewhere, we suggest that adult survival is unlikely a major contributor to declining populations, and other factors like habitat loss may be of more concern.
Journal Article
Annual Survival and Seasonal Hunting Mortality of Midcontinent Snow Geese
2017
Annual banding programs have allowed the estimation of key demographic parameters for many populations of harvested wildlife, yet they often provide little insight into vital rate variation among seasonally occupied habitats or among regions with differing hunting regulations. For lesser snow geese (Chen caerulescens caerulescens) in the midcontinent of North America, rapid growth in abundance and the consequent implementation of special conservation measures present a scenario where seasonal mortality estimates would be highly valuable. We evaluated variation in hunting mortality of adult and young geese among 3 seasons (autumn, winter, and spring) based on annual banding data from breeding colonies north and south of 60°N latitude, and seasonal hunting recoveries from the United States and Canada. Using band-recovery models and data covering 1999 through 2015, we first estimated annual survival for geese of both age classes and breeding locations, and then subsequently used seasonal hunting recoveries to derive estimates of seasonal hunting mortality and annual non-hunting mortality. Simulation models validated the accuracy of this approach. Hunting mortality in winter generally exceeded that during spring and autumn, but our estimates suggested that hunting mortality represented a small fraction of annual mortality for adult and young birds. Consistent with recent studies, our estimates pointed to a greater harvest effect for the smaller subarctic population breeding near southern Hudson Bay, Canada, than for the large arctic population breeding farther north. Although mean kill rates were higher for young than adult geese, natural mortality for young was high and temporally variable, implying that some hunting mortality experienced by young geese during their first year could be compensated by natural causes of death. Natural (non-hunting) mortality and annual survival showed greater temporal variation than seasonal kill rates in adults and young geese, highlighting the importance of non-harvest factors (e.g., climate, habitat, population density) to the dynamics of these populations. These novel estimates of seasonal kill rates and non-hunting mortality contribute further support to the notion that internal dynamics of the lesser snow goose midcontinent population, including natural mortality and recruitment, currently influence population trajectory more than ongoing interventions through harvest management.
Journal Article
Changing knowledge, attitudes and behaviours towards cytomegalovirus in pregnancy through film-based antenatal education: a feasibility randomised controlled trial of a digital educational intervention
2021
Background
Congenital cytomegalovirus (CMV) is the most common congenital infection globally, however information about CMV is not routinely included in antenatal education in the United Kingdom. This feasibility study aimed to gather the essential data needed to design and power a large randomised controlled trial (RCT) to investigate the efficacy of a digital intervention in reducing the risk of CMV acquisition in pregnancy. In order to do this, we carried out a single-centre RCT, which explored the knowledge, attitudes and risk reduction behaviours in women in the intervention and treatment as usual groups, pre- and post-intervention.
Methods
CMV seronegative women living with a child less than four years old, receiving antenatal care at a single UK tertiary centre, were randomised to the digital intervention or ‘treatment as usual’ groups. Participants completed questionnaires before the digital intervention and after and at 34 gestational weeks, and responses within groups and between groups were compared using tailored randomisation tests. CMV serology was tested in the first trimester and at the end of pregnancy.
Results
Of the 878 women screened, 865 samples were analysed with 43% (
n
= 372) being CMV seronegative and therefore eligible to take part in the RCT; of these, 103 (27.7%) women were enrolled and 87 (84%) of these completed the study. Most participants (
n
= 66; 64%) were unfamiliar with CMV at enrolment, however at 34 gestational weeks, women in the intervention group (
n
= 51) were more knowledgeable about CMV compared to the treatment as usual group (
n
= 52) and reported engaging in activities that may increase the risk of CMV transmission less frequently. The digital intervention was highly acceptable to pregnant women. Overall, four participants seroconverted over the course of the study: two from each study group.
Conclusions
A large multi-centre RCT investigating the efficacy of a CMV digital intervention is feasible in the United Kingdom; this study has generated essential data upon which to power such a study. This single-centre feasibility RCT demonstrates that a digital educational intervention is associated with increase in knowledge about CMV and can result in behaviour change which may reduce the risk of CMV acquisition in pregnancy.
Trial registration
Clinicaltrials.gov,
NCT03511274
, Registered 27.04.18,
http://www.Clinicaltrials.gov
Journal Article
Fitness heterogeneity in adult Snow and Ross's geese: Survival is higher in females with brood patches
by
Kellett, Dana K.
,
Calvert, Anna M.
,
Alisauskas, Ray T.
in
adults
,
Animal breeding
,
Anser caerulescens caerulescens
2019
Life-history theory broadly predicts a fitness tradeoff between costs of raising offspring and parental survival. Waterfowl with precocial young face particularly high costs of egg production, incubation, and brood-rearing, but not all evidence supports a corresponding decline in survival. We used multi-state mark–recapture–recovery models to estimate annual probabilities of survival, reported mortality, and transition between 2 states for female Ross's Geese (Anser rossii) and Lesser Snow Geese (A. caerulescens caerulescens) that attempted nesting near Karrak Lake, Nunavut, Canada. States were possession of a brood patch (high likelihood of successful nesting, “B”) vs. no brood patch (attempted nesting but failed, “N”). Based on over 43,000 birds marked from 2000 to 2015, we found that females of each species with a brood patch had consistently higher probabilities of survival than those without, subsequent to capture in early August. Virtually all of the state differences in survival were due to nonhunting mortality. These patterns are consistent with the concept of variable individual quality impacting vital rates across multiple seasons. Higher survival of females with brood patches may be linked to greater breeding success but also to a hypothesized dominance advantage afforded to family groups of geese during winter. Moreover, although hunting pressure can play a key role in regulating Arctic goose populations, it does not appear to affect this relationship between inferred breeding state and survival. Instead, coincident with recent declines in harvest rate in these populations, higher individual quality of breeding females appears to outweigh the higher hunting vulnerability of presumed parents with young. The potential influence of social dominance in reducing natural winter mortality among families may thus contribute to the survival advantage seen in successful, relative to failed, breeders.
Journal Article
Experimental test for a trade-off between successful nesting and survival in capital breeders with precocial offspring
by
Drake, Kiel L.
,
Calvert, Anna M.
,
Alisauskas, Ray T.
in
Animal behavior
,
Animal reproduction
,
Anser rossii
2018
Life history theory assumes a trade-off between reproduction and survival. Investigations of this trade-off in birds have focused primarily on costs of rearing altricial young, because such costs are assumed to be low in species with precocial young. We experimentally manipulated nest success to test for a trade-off between (1) raising offspring for up to 1 yr after successfully nesting and (2) survival in female Ross's Geese (Chen rossii), a species with self-feeding, precocial young. We used multistate capture–resighting analysis that also incorporated recoveries of dead birds for inference about survival. We detected a general negative effect of successful nesting on survival, whereby point estimates of annual survival for successfully nesting females were consistently lower than those for failed nesters. Failed nesters had a greater proportion of mortality attributable to hunting, judging from their higher rates of reported mortality by hunters compared to successful nesters; thus, a cost of breeding associated with successful nesting likely resulted from natural mortality factors during incubation and brood rearing, and not from exploitation by humans.
Journal Article