In studies of wild animals, one frequently encounters both census and mark-recapture-recovery data. We show how a state-space model for census data in combination with the usual multinomial-based models for ring-recovery data provide estimates of productivity not available from either type of data alone. The approach is illustrated on two British bird species. For the lapwing, we calibrate how its recent decline could be due to a decrease in productivity. For the heron, there is no evidence for a decline in productivity, and the combined analysis increases significantly the strength of logistic regressions of survival on winter severity.
With the expansion in the quantity and types of biodiversity data being collected, there is a need to find ways to combine these different sources to provide cohesive summaries of species' potential and realized distributions in space and time. Recently, model-based data integration has emerged as a means to achieve this by combining datasets in ways that retain the strengths of each. We describe a flexible approach to data integration using point process models, which provide a convenient way to translate across ecological currencies. We highlight recent examples of large-scale ecological models based on data integration and outline the conceptual and technical challenges and opportunities that arise. Species Distribution Models in EcologyLarge-scale ecological models of how species distributions and abundances vary over space and time are a critical tool in macroecology, biogeography, and conservation biology. They underpin our understanding of how biodiversity is shaped, how it is responding to anthropogenic activities, and how it might change in the future [1][2][3]. There is now a substantial literature on statistical tools for building species distribution models (SDMs) (see Glossary) and best practice in how to fit them [4][5][6][7]. SDMs also form a building block upon which more complex models, incorporating occupancy and/or abundance in space and time, can be built [8,9].
S.. 2017. Bumblebee family lineage survival is enhanced in high-quality landscapes. Nature, 543 (7646). 547-549. 10.1038/nature21709Contact CEH NORA team at noraceh@ceh.ac.ukThe NERC and CEH trademarks and logos ('the Trademarks') are registered trademarks of NERC in the UK and other countries, and may not be used without the prior written consent of the Trademark owner. 1Bumblebee family lineage survival is enhanced in high quality landscapes Main textThe loss of semi-natural habitats and floral resources within intensively managed agricultural landscapes has been identified as a major driver of declines in insect pollinators 3,9,10 , with negative consequences for crop pollination 11 . Habitat restoration (e.g. the planting of flowering hedgerows, meadows or flower strips along field margins under agri-environment schemes 12 )can mitigate these effects, increasing local pollinator abundance and species richness 13-15 and enhancing rates of persistence and colonization at the community level 16 . However, we lack understanding of the effects of restoration on key aspects of pollinator biology that may explain the mechanisms behind these responses. In particular, improving habitat quality might be expected to enhance the prospects of successful reproduction and between-year survival in targeted areas, but whether this occurs is unknown.3 Bumblebees (Bombus spp.) are key pollinators of wild flowers and commercial crops 17,18 .Following a eusocial, annual colony cycle, new queens enter hibernation in the autumn and emerge in spring to search for a nest site and found a colony. Each colony may produce up to several hundred 'daughter' workers, which forage from spring to summer at flowers for nectar and pollen to rear new daughter queens and males 19 . The survival and dispersal patterns of bumblebee queens during hibernation and nest-searching periods are critical to overall population persistence, but remain undescribed in wild populations 8,20,21 . In addition, although the availability of floral resources within foraging distance of the nest has been shown to increase numbers of workers and males produced per colony, effects on queen production have been less clear 22 and there is no evidence regarding how queen production, survival and dispersal may be linked with underlying habitat quality and land-use 23 .Here, we investigated the effects of habitat quality and land-use on bumblebee survival and dispersal between colony cycle stages across two years. We first tested whether colonies located within or near high-value foraging habitats had a greater probability of producing daughter queens that survive the winter hibernation and spring emergence stages, henceforth termed 'family lineage survival'. Second, we tested whether the distances travelled by queens between hibernation and nest-searching periods (as a measure of minimum relative queen dispersal distances within our study landscape) were affected by the proportion of high quality habitat surrounding their natal colony. We sampled DNA non-lethally from...
We present a survival analysis of Soay sheep mark recapture and recovery data. Unlike previous conditional analyses, it is not necessary to assume equality of recovery and recapture probabilities; instead these are estimated by maximum likelihood. Male and female sheep are treated separately, with the higher numbers and survival probabilities of the females resulting in a more complex model than that used for the males. In both cases, however, age and time aspects need to be included and there is a strong indication of a reduction in survival for sheep aged 7 years or more. Time variation in survival is related to the size of the population and selected weather variables, by using logistic regression. The size of the population signi®cantly affects the survival probabilities of male and female lambs, and of female sheep aged 7 or more years. March rainfall and a measure of the North Atlantic oscillation are found to in¯uence survival signi®cantly for all age groups considered, for both males and females. Either of these weather variables can be used in a model. Several phenotypic and genotypic individual covariates are also ®tted. The only covariate which is found to in¯uence survival signi®cantly is the type of horn of ®rst-year female sheep. There is a substantial variation in the recovery probabilities over time, re¯ecting in part the increased effort when a population crash was expected. The goodness of ®t of the model is checked by using graphical procedures.
Summary1. Agri-environment schemes (AES) are used extensively across Europe to address biodiversity declines in farmland. In England, Environmental Stewardship (ES) was introduced in 2005 to address the shortcomings of previous schemes, but as for schemes in other countries, assessments to date have revealed little evidence for national-scale biodiversity benefits. 2. Here, we assess the efficacy of ES in driving changes in national farmland bird populations over the period 2002-2010, using BTO ⁄ JNCC ⁄ RSPB Breeding Bird Survey data. We tested for associations between ES management options, grouped into categories reflecting intended biological effects (e.g. stubble), and species' population growth rates, wherever benefits of management might be expected to occur. 3. We found strong evidence for positive effects of management that provides winter food resources (i.e. ES stubble and wild bird seed [WBS] crops) on population growth rates across multiple granivorous species, at three landscape scales. The results for management aiming to provide breeding season benefits (i.e. grassland, field margin and boundary [hedge, ditch] management) showed mixed patterns of positive and negative associations. 4. The results for stubble and WBS provide the first evidence for landscape-scale responses of biodiversity to AES management. The negative relationships identified may also show the importance of management context driving unforeseen predation or competition effects. 5. Synthesis and Applications. This study demonstrates that agri-environment scheme management has the potential to have national-scale effects on avian population growth rates, although our results suggest that some components of the scheme have had little effect on bird populations. Therefore, whilst this study provides the first proof-of-concept for broad-and-shallow scheme impacts on biodiversity, our results underline the importance of targeting towards populationlimiting factors, here winter food resources. A combination of low uptake of key in-field options that provide winter seed and a failure to cover the late-winter period effectively explains the lack of national population responses. Such issues need to be addressed before schemes like Environmental Stewardship will achieve their goals. This study shows the value of feedback from monitoring for informing scheme design, through identifying problems and testing solutions.
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