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2. Irruptions of crossbills Loxia spp. in northern Europe – patterns and correlations with seed production by key and non‐key conifers.

Author

Summers, Ron W., Swallow, Ben, Fridman, Jonas, Hokkanen, Tatu, Newton, Ian, and Buckland, Stephen T.

Subjects
NORWAY spruce, SCOTS pine, SEED industry, FRUIT seeds, SILVER fir
Abstract

Irruptions by boreal seed‐eating and frugivorous birds are assumed to be driven by the production of seeds and fruits, crops of which are highly variable between years. Using data from Sweden, we tested whether irruptions of Common Crossbills Loxia curvirostra were correlated with low Norway Spruce Picea abies seed production in the same year as the irruption and/or high seed production in the year prior to an irruption. Similar tests were made for Parrot Crossbill Loxia pytyopsittacus irruptions in relation to Scots Pine Pinus sylvestris seed production. In northern Europe, these conifers represent the key food species of the two crossbill species, respectively. Despite differing times that seeds take to mature and asynchronous seed production between the two conifer species, including a 3‐year cycle for Norway Spruce, the two crossbill species often irrupted in the same year as one another. Analyses showed that irruptions into Britain and other parts of western Europe by both crossbill species were correlated with low seed production by Norway Spruce in Sweden. Low seed production by Scots Pine had a marginally non‐significant additive effect on both crossbill species. In a second set of analyses, the best‐fitting model was one in which low seed production by both conifers in a given year and high seed production in the previous year were each correlated with large numbers of irrupting Common and Parrot Crossbills. The models indicate that the incidental co‐occurrence of low seed production of Norway Spruce and Scots Pine in a given year, after a year of high seed production, may result in an irruption. The seed production of Norway Spruce and Scots Pine in Sweden was correlated with production by the same species in Finland, indicating widespread synchrony of cropping across northern Europe. [ABSTRACT FROM AUTHOR]

Published
2024
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17. Developing and enhancing biodiversity monitoring programmes: a collaborative assessment of priorities

Author

Pocock, Michael J. O., Newson, Stuart E., Henderson, Ian G., Peyton, Jodey, Sutherland, William J., Noble, David G., Ball, Stuart G., Beckmann, Björn C., Biggs, Jeremy, Brereton, Tom, Bullock, David J., Buckland, Stephen T., Edwards, Mike, Eaton, Mark A., Harvey, Martin C., Hill, Mark O., Horlock, Martin, Hubble, David S., Julian, Angela M., Mackey, Edward C., Mann, Darren J., Marshall, Matthew J., Medlock, Jolyon M., O'Mahony, Elaine M., Pacheco, Marina, Porter, Keith, Prentice, Steve, Procter, Deborah A., Roy, Helen E., Southway, Sue E., Shortall, Chris R., Stewart, Alan J. A., Wembridge, David E., Wright, Mark A., and Roy, David B.

Published
2015

19. Contributors

Author

Acevedo-Gutiérrez, Alejandro, primary, Adam, Peter J., additional, Aguilar, Alex, additional, Amano, Masao, additional, Anderson, Paul K., additional, Archer, Frederick I., additional, Arnould, John P.Y., additional, Atkinson, Shannon, additional, Au, Whitlow W.L., additional, Aurioles-Gamboa, David, additional, Javier Aznar, F., additional, Baird, Robin W., additional, Baker, C. Scott, additional, Ballance, Lisa T., additional, Balbuena, Juan A., additional, Bannister, John L., additional, Barlow, Jay, additional, Barton, Sheri L., additional, Bearzi, Giovanni, additional, Beasley, Isabel, additional, Bekoff, Marc, additional, Ben-David, M., additional, Bengtson, John L., additional, Berta, Annalisa, additional, Bérubé, Martine, additional, Bester, Marthán N., additional, Bianucci, Giovanni, additional, Bjørge, Arne, additional, Black, Nancy A., additional, Bodkin, J.L., additional, Bonde, Robert K., additional, Borger, Jill, additional, Borrell, Asuncion, additional, Boveng, Peter, additional, Bowen, W.D., additional, Boyd, Ian L., additional, Braulik, Gillian T., additional, Brown, Alexander M., additional, Brownell, Robert L., additional, Buckland, Stephen T., additional, Burns, John J., additional, Cabrera, Andrea A., additional, Campagna, Claudio, additional, Cantor, Mauricio, additional, Cárdenas-Alayza, Susana, additional, Cárdenas-Hinojosa, Gustavo, additional, Castellini, Michael, additional, Cerchio, Salvatore, additional, Champagne, Cory D., additional, Chilvers, B. Louise, additional, Chivers, Susan J., additional, Cipriano, Frank, additional, Clapham, Phillip J., additional, Constantine, Rochelle, additional, Cooper, Lisa N., additional, Corkeron, Peter, additional, Costa, Daniel P., additional, Costidis, Alexander M., additional, Cowan, Daniel F., additional, Cranford, Ted, additional, Crespo, Enrique A., additional, Crocker, Daniel E., additional, Croll, Donald A., additional, da Silva, Vera M.F., additional, Danil, Kerri, additional, Darling, Jim, additional, Dawson, Stephen M., additional, de Muizon, Christian, additional, de Vos, Asha, additional, Dehnhardt, Guido, additional, DeMaster, Douglas P., additional, Deméré, Thomas A., additional, Dendrinos, Panagiotis, additional, Dill, Lawrence M., additional, Dizon, Andrew E., additional, L. Dolar, M. Louella, additional, Domning, Daryl P., additional, Donovan, G.P., additional, Dudzinski, Kathleen M., additional, Duffield, Deborah A., additional, Dyer, Michael P., additional, Ellis, Richard, additional, Eskelinen, Holli, additional, Estes, James A., additional, Evans, Peter G.H., additional, Fernández, Mercedes, additional, Fertl, Dagmar, additional, Fettuccia, Daniela de Castro, additional, Fiedler, Paul C., additional, Fish, Frank E., additional, Flores, Paulo A.C., additional, Forcada, Jaume, additional, Ford, John K.B., additional, Fordyce, R. Ewan, additional, Forestell, Paul H., additional, Forney, Karin A., additional, Fowler, Charles W., additional, Frankel, Adam S., additional, Friedlaender, Ari S., additional, Frohoff, Toni, additional, Frost, Kathryn J., additional, Galatius, Anders, additional, García-Vernet, Raquel, additional, Geisler, Jonathan H., additional, Gelatt, Thomas S., additional, Gentry, Roger, additional, George, J. Craig, additional, Gerrodette, Tim, additional, Goldbogen, Jeremy A., additional, Goldsworthy, Simon D., additional, P. Goodall, R. Natalie, additional, Goodman, Simon J., additional, Gregg, Justin D., additional, Hall, Ailsa J., additional, Hammill, Mike O., additional, Hammond, Philip S., additional, Hanke, Frederike D., additional, Hartman, Karin L., additional, Hazen, Elliott, additional, Heide-Jørgensen, M.P., additional, Heithaus, Michael R., additional, Herman, Louis M., additional, Herzing, Denise L., additional, Hewitt, Roger P., additional, Hindell, Mark A., additional, Hoelzel, A. Rus, additional, Hofmeyr, G. J. Greg, additional, Hohn, Aleta A., additional, Hooker, Sascha K., additional, Horstmann, Lara, additional, Horwood, Joseph, additional, Hoyt, Erich, additional, Hückstädt, Luis A., additional, Ivashchenko, Yulia V., additional, Iverson, Sara J., additional, Janik, Vincent M., additional, Jaramillo-Legorreta, Armando M., additional, Jefferson, Thomas A., additional, Jensen, Anne M., additional, Karamanlidis, Alexandros A., additional, Kasuya, Toshio, additional, Kato, Hidehiro, additional, Keith Diagne, Lucy W., additional, Kemp, Christopher, additional, Kemper, Catherine M., additional, Kenney, Robert D., additional, Kinze, Carl C., additional, Kirkman, Stephen P., additional, Kiszka, Jeremy J., additional, Koopman, Heather N., additional, Kooyman, Gerald L., additional, Kovacs, Kit M., additional, Kraus, Scott D., additional, Krysl, Petr, additional, Laidre, Kristin L., additional, Laitman, Jeffrey T., additional, Lambert, Olivier, additional, Landry, André M., additional, Lavigne, David M., additional, LeDuc, Rick, additional, Lipsky, Jessica D., additional, Littnan, Charles, additional, Loughlin, Thomas R., additional, Lowry, Lloyd, additional, Lowther, Andrew D., additional, Lydersen, Christian, additional, Maas, Mary C., additional, MacLean, Stephen A., additional, MacLeod, Colin D., additional, Mallette, Sarah D., additional, Mann, Janet, additional, Maresh, Jennifer L., additional, Marsh, Helene, additional, Marshall, Christopher D., additional, Martin, Anthony R., additional, Mass, Alla M., additional, McAlpine, Donald F., additional, Chris McKnight, J., additional, McLellan, William A., additional, Mead, James G., additional, Melin, Sharon R., additional, Merrick, Richard, additional, Mesnick, Sarah L., additional, Miller, Edward H., additional, Miller, Lance J., additional, Miller, Patrick J.O., additional, Miyazaki, Nobuyuki, additional, Moore, Jeffrey E., additional, Moore, Kathleen M., additional, Moore, Michael, additional, Moore, Sue E., additional, Moors-Murphy, Hilary B., additional, Morin, Phillip A., additional, Newman, William A., additional, Newton, Kelly M., additional, Nieto-García, Edwyna, additional, Northridge, Simon, additional, Nummela, Sirpa, additional, O'Brien, Justine K., additional, O'Corry-Crowe, Gregory M., additional, Olsen, Morten T., additional, Olson, Paula A., additional, Oppenheimer, Jonas, additional, Orbach, Dara N., additional, Ortiz, Rudy M., additional, Pabst, D. Ann, additional, Palsbøll, Per J., additional, Parra, Guido J., additional, Patterson, Eric, additional, Paves-Hernández, Héctor, additional, Perrin, William F., additional, Perryman, Wayne L., additional, Pitman, Robert, additional, Pomeroy, Patrick P., additional, Ponganis, Paul J., additional, Powell, James A., additional, Pyenson, Nicholas D., additional, Racicot, Rachel, additional, Raga, J. Antonio, additional, Ralls, Katherine, additional, Raverty, Stephen, additional, Read, Andrew J., additional, Reeves, Randall R., additional, Regehr, Eric V., additional, Reggente, Melissa A.L., additional, Reidenberg, Joy S., additional, Reijnders, Peter J.H., additional, Reyes, Julio C., additional, Reynolds, John E., additional, Robeck, Todd R., additional, Robinson, Kelly J., additional, Rode, Karyn, additional, Rogers, Tracey, additional, Rojas-Bracho, Lorenzo, additional, Roman, Joe, additional, Rommel, Sentiel A., additional, Roos, Marjoleine M.H., additional, Rosel, Patricia E., additional, Rowntree, Victoria J., additional, Rugh, David, additional, Russell, Debbie J.F., additional, Sayigh, Laela S., additional, Scolardi, Kerri M., additional, Scott, Michael D., additional, Sears, Richard, additional, Seger, Jon, additional, Sharp, Sarah, additional, Sheehan, Glenn W., additional, Silber, Gregory K., additional, Simeone, Claire A., additional, Smith, Brian D., additional, Southall, Brandon L., additional, Spitz, Jérôme, additional, Spoor, Fred, additional, Stacey, Rita, additional, Staniland, Iain J., additional, Steel, Debbie, additional, Stern, S. Jonathan, additional, Stewart, Brent S., additional, Supin, Alexander Y., additional, Suydam, R., additional, Swartz, Steven L., additional, Teilmann, Jonas, additional, Tershy, Bernie R., additional, Thewissen, J.G.M., additional, Tinker, M.T., additional, Tolley, Krystal A., additional, Trillmich, Fritz, additional, Trites, Andrew W., additional, Turner, Ted, additional, Twiss, Sean D., additional, Tyack, Peter L., additional, Uhen, Mark D., additional, Van Franeker, Jan A., additional, Van Waerebeek, Koen, additional, Wade, Paul R., additional, Wang, John Y., additional, Weller, David W., additional, Wells, Randall S., additional, Werth, Alexander J., additional, Whitehead, Hal, additional, Williams, Terrie M., additional, Würsig, Bernd, additional, Yablokov, Alexey V., additional, Yamada, Tadasu K., additional, Yamato, Maya, additional, Yochem, Pamela K., additional, York, Anne E., additional, and Zhou, Kaiya, additional

Published
2018
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22. Fire and biodiversity in the Anthropocene

Author

Kelly, Luke T., primary, Giljohann, Katherine M., additional, Duane, Andrea, additional, Aquilué, Núria, additional, Archibald, Sally, additional, Batllori, Enric, additional, Bennett, Andrew F., additional, Buckland, Stephen T., additional, Canelles, Quim, additional, Clarke, Michael F., additional, Fortin, Marie-Josée, additional, Hermoso, Virgilio, additional, Herrando, Sergi, additional, Keane, Robert E., additional, Lake, Frank K., additional, McCarthy, Michael A., additional, Morán-Ordóñez, Alejandra, additional, Parr, Catherine L., additional, Pausas, Juli G., additional, Penman, Trent D., additional, Regos, Adrián, additional, Rumpff, Libby, additional, Santos, Julianna L., additional, Smith, Annabel L., additional, Syphard, Alexandra D., additional, Tingley, Morgan W., additional, and Brotons, Lluís, additional

Published
2020
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24. Fire and biodiversity in the Anthropocene

Author

Centre Tecnològic Forestal de Catalunya, University of Melbourne, Australian Research Council, Xunta de Galicia, Foundation for Science and Technology, European Commission, Ministerio de Economía y Competitividad (España), Kelly, Luke T., Giljohann, Katherine M., Duane, Andrea, Aquilué, Núria, Archibald, Sally, Batllori, Enric, Bennett, Andrew F., Buckland, Stephen T., Canelles, Quim, Clarke, Michael F., Fortin, Marie-Josée, Hermoso, Virgilio, Herrando, Sergi, Keane, Robert E., Lake, Frank K., McCarthy, Michael A., Morán-Ordóñez, Alejandra, Parr, Catherine L., Pausas, J. G., Penman, Trent D., Regos, Adrián, Rumpff, Libby, Santos, Julianna L., Smith, Annabel L., Syphard, Alexandra D., Tingley, Morgan W., Brotons, Lluís, Centre Tecnològic Forestal de Catalunya, University of Melbourne, Australian Research Council, Xunta de Galicia, Foundation for Science and Technology, European Commission, Ministerio de Economía y Competitividad (España), Kelly, Luke T., Giljohann, Katherine M., Duane, Andrea, Aquilué, Núria, Archibald, Sally, Batllori, Enric, Bennett, Andrew F., Buckland, Stephen T., Canelles, Quim, Clarke, Michael F., Fortin, Marie-Josée, Hermoso, Virgilio, Herrando, Sergi, Keane, Robert E., Lake, Frank K., McCarthy, Michael A., Morán-Ordóñez, Alejandra, Parr, Catherine L., Pausas, J. G., Penman, Trent D., Regos, Adrián, Rumpff, Libby, Santos, Julianna L., Smith, Annabel L., Syphard, Alexandra D., Tingley, Morgan W., and Brotons, Lluís

Abstract

Fire has been a source of global biodiversity for millions of years. However, interactions with anthropogenic drivers such as climate change, land use, and invasive species are changing the nature of fire activity and its impacts. We review how such changes are threatening species with extinction and transforming terrestrial ecosystems. Conservation of Earth’s biological diversity will be achieved only by recognizing and responding to the critical role of fire. In the Anthropocene, this requires that conservation planning explicitly includes the combined effects of human activities and fire regimes. Improved forecasts for biodiversity must also integrate the connections among people, fire, and ecosystems. Such integration provides an opportunity for new actions that could revolutionize how society sustains biodiversity in a time of changing fire activity.

Published
2020

27. Review of potential line-transect methodologies for estimating abundance of dolphin stocks in the eastern tropical Pacific

Author

Lennert-Cody, Cleridy E, Buckland, Stephen T, Gerrodette, Tim, Webb, Andrew, Barlow, Jay, Fretwell, Peter, Maunder, Mark N, Kitakado, Toshihide, Moore, Jeffrey E, Scott, Michael D, Skaug, Hans J, Lennert-Cody, Cleridy E, Buckland, Stephen T, Gerrodette, Tim, Webb, Andrew, Barlow, Jay, Fretwell, Peter, Maunder, Mark N, Kitakado, Toshihide, Moore, Jeffrey E, Scott, Michael D, and Skaug, Hans J

Abstract

A twelve-year hiatus in fishery-independent marine mammal surveys in the eastern tropical Pacific Ocean (ETP), combined with a mandate to monitor dolphin stock status under international agreements and the need for reliable stock status information to set dolphin bycatch limits in the tuna purse-seine fishery, has renewed debate about how best to assess and monitor ETP dolphin stock status. The high cost of replicating previous ship-based surveys has intensified this debate. In this review, transect methods for estimating animal abundance from dedicated research surveys are considered, with a focus on both contemporary and potential methods suitable for surveying large areas for dolphin species that can form large, multi-species aggregations. Covered in this review are potential improvements to the previous ship-based survey methodology, other ship-based methods, alternative approaches based on high-resolution imagery and passive acoustics, and combinations of ship-based and alternative approaches. It is concluded that for immediate management needs, ship-based surveys, with some suggested modifications to improve precision, are the only reliable option despite their high cost. However, it is recommended that a top research priority should be development of composite methods. Pilot studies on the use of high-resolution imagery and passive acoustics for development of indices of relative abundance to be used in composite methods should be part of any future ship-based survey efforts.

Published
2018

28. Identifying multi-species synchrony in response to environmental covariates

Author

Swallow, Ben, King, Ruth, Buckland, Stephen T, and Toms, Mike P.

Abstract

The importance of multispecies models for understanding complex ecological processes and interactions is beginning to be realized. Recent developments, such as those by Lahoz-Monfort et al. (2011), have enabled synchrony in demographic parameters across multiple species to be explored. Species in a similar environment would be expected to be subject to similar exogenous factors, although their response to each of these factors may be quite different. The ability to group species together according to how they respond to a particular measured covariate may be of particular interest to ecologists. We fit a multispecies model to two sets of similar species of garden bird monitored under the British Trust for Ornithology's Garden Bird Feeding Survey. Posterior model probabilities were estimated using the reversible jump algorithm to compare posterior support for competing models with different species sharing different subsets of regression coefficients. There was frequently good agreement between species with small asynchronous random-effect components and those with posterior support for models with shared regression coefficients; however, this was not always the case. When groups of species were less correlated, greater uncertainty was found in whether regression coefficients should be shared or not. The methods outlined in this study can test additional hypotheses about the similarities or synchrony across multiple species that share the same environment. Through the use of posterior model probabilities, estimated using the reversible jump algorithm, we can detect multispecies responses in relation to measured covariates across any combination of species and covariates under consideration. The method can account for synchrony across species in relation to measured covariates, as well as unexplained variation accounted for using random effects. For more flexible, multiparameter distributions, the support for species-specific parameters can also be measured.

Published
2016
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29. Identifying multispecies synchrony in response to environmental covariates

Author

Swallow, Ben, King, Ruth, Buckland, Stephen T., and Toms, Mike P.

Subjects
ecosystem modeling, multispecies, synchrony, Tweedie, predation, Original Research
Abstract

The importance of multispecies models for understanding complex ecological processes and interactions is beginning to be realized. Recent developments, such as those by Lahoz‐Monfort et al. (2011), have enabled synchrony in demographic parameters across multiple species to be explored. Species in a similar environment would be expected to be subject to similar exogenous factors, although their response to each of these factors may be quite different. The ability to group species together according to how they respond to a particular measured covariate may be of particular interest to ecologists. We fit a multispecies model to two sets of similar species of garden bird monitored under the British Trust for Ornithology's Garden Bird Feeding Survey. Posterior model probabilities were estimated using the reversible jump algorithm to compare posterior support for competing models with different species sharing different subsets of regression coefficients. There was frequently good agreement between species with small asynchronous random‐effect components and those with posterior support for models with shared regression coefficients; however, this was not always the case. When groups of species were less correlated, greater uncertainty was found in whether regression coefficients should be shared or not. The methods outlined in this study can test additional hypotheses about the similarities or synchrony across multiple species that share the same environment. Through the use of posterior model probabilities, estimated using the reversible jump algorithm, we can detect multispecies responses in relation to measured covariates across any combination of species and covariates under consideration. The method can account for synchrony across species in relation to measured covariates, as well as unexplained variation accounted for using random effects. For more flexible, multiparameter distributions, the support for species‐specific parameters can also be measured.

Published
2016

38. Model selection with overdispersed distance sampling data.

Author

Matthiopoulos, Jason, Buckland, Stephen T., Howe, Eric J., Després‐Einspenner, Marie‐Lyne, and Kühl, Hjalmar S.

Subjects
SAMPLING (Process), ACQUISITION of data, ANIMAL population density, SIMULATION methods & models, ANIMAL diversity conservation
Abstract

Distance sampling (DS) is a widely used framework for estimating animal abundance. DS models assume that observations of distances to animals are independent. Non‐independent observations introduce overdispersion, causing model selection criteria such as AIC or AICc to favour overly complex models, with adverse effects on accuracy and precision.We describe, and evaluate via simulation and with real data, estimators of an overdispersion factor (c^), and associated adjusted model selection criteria (QAIC) for use with overdispersed DS data. In other contexts, a single value of c^ is calculated from the "global" model, that is the most highly parameterised model in the candidate set, and used to calculate QAIC for all models in the set; the resulting QAIC values, and associated ΔQAIC values and QAIC weights, are comparable across the entire set. Candidate models of the DS detection function include models with different general forms (e.g. half‐normal, hazard rate, uniform), so it may not be possible to identify a single global model. We therefore propose a two‐step model selection procedure by which QAIC is used to select among models with the same general form, and then a goodness‐of‐fit statistic is used to select among models with different forms. A drawback of this approach is that QAIC values are not comparable across all models in the candidate set.Relative to AIC, QAIC and the two‐step model selection procedure avoided overfitting and improved the accuracy and precision of densities estimated from simulated data. When applied to six real datasets, adjusted criteria and procedures selected either the same model as AIC or a model that yielded a more accurate density estimate in five cases, and a model that yielded a less accurate estimate in one case.Many DS surveys yield overdispersed data, including cue counting surveys of songbirds and cetaceans, surveys of social species including primates, and camera‐trapping surveys. Methods that adjust for overdispersion during the model selection stage of DS analyses therefore address a conspicuous gap in the DS analytical framework as applied to species of conservation concern. [ABSTRACT FROM AUTHOR]

Published
2019
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39. Review of potential line-transect methodologies for estimating abundance of dolphin stocks in the eastern tropical Pacific.

Author

LENNERT-CODY, CLERIDY E., BUCKLAND, STEPHEN T., GERRODETTE, TIM, WEBB, ANDREW, BARLOW, JAY, FRETWELL, PETER T., MAUNDER, MARK N., KITAKADO, TOSHIHIDE, MOORE, JEFFREY E., SCOTT, MICHAEL D., and SKAUG, HANS J.

Subjects
*MARINE mammals, *BOTTLENOSE dolphin, *TRANSECT method, *DOLPHINS, *EARNINGS forecasting, *TUNA fisheries, *INTERNATIONAL obligations, *HYDROGRAPHIC surveying
Abstract

A twelve-year hiatus in fishery-independent marine mammal surveys in the eastern tropical Pacific Ocean (ETP), combined with a mandate to monitor dolphin stock status under international agreements and the need for reliable stock status information to set dolphin bycatch limits in the tuna purse-seine fishery, has renewed debate about how best to assess and monitor ETP dolphin stock status. The high cost of replicating previous ship-based surveys has intensified this debate. In this review, transect methods for estimating animal abundance from dedicated research surveys are considered, with a focus on both contemporary and potential methods suitable for surveying large areas for dolphin species that can form large, multi-species aggregations. Covered in this review are potential improvements to the previous ship-based survey methodology, other ship-based methods, alternative approaches based on high-resolution imagery and passive acoustics, and combinations of ship-based and alternative approaches. It is concluded that for immediate management needs, ship-based surveys, with some suggested modifications to improve precision, are the only reliable option despite their high cost. However, it is recommended that a top research priority should be development of composite methods. Pilot studies on the use of high-resolution imagery and passive acoustics for development of indices of relative abundance to be used in composite methods should be part of any future ship-based survey efforts. [ABSTRACT FROM AUTHOR]

Published
2018

43. Bayesian hierarchical modelling of continuous non-negative longitudinal data with a spike at zero: An application to a study of birds visiting gardens in winter.

Author

Swallow, Ben, Buckland, Stephen T., King, Ruth, and Toms, Mike P.

Abstract

The development of methods for dealing with continuous data with a spike at zero has lagged behind those for overdispersed or zero-inflated count data. We consider longitudinal ecological data corresponding to an annual average of 26 weekly maximum counts of birds, and are hence effectively continuous, bounded below by zero but also with a discrete mass at zero. We develop a Bayesian hierarchical Tweedie regression model that can directly accommodate the excess number of zeros common to this type of data, whilst accounting for both spatial and temporal correlation. Implementation of the model is conducted in a Markov chain Monte Carlo (MCMC) framework, using reversible jump MCMC to explore uncertainty across both parameter and model spaces. This regression modelling framework is very flexible and removes the need to make strong assumptions about mean-variance relationships a priori. It can also directly account for the spike at zero, whilst being easily applicable to other types of data and other model formulations. Whilst a correlative study such as this cannot prove causation, our results suggest that an increase in an avian predator may have led to an overall decrease in the number of one of its prey species visiting garden feeding stations in the United Kingdom. This may reflect a change in behaviour of house sparrows to avoid feeding stations frequented by sparrowhawks, or a reduction in house sparrow population size as a result of sparrowhawk increase. [ABSTRACT FROM AUTHOR]

Published
2016
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44. Chronic exposure to neonicotinoids increases neuronal vulnerability to mitochondrial dysfunction in the bumblebee (Bombus terrestris).

Author

Moffat, Christopher, Goncalves Pacheco, Joao, Sharp, Sheila, Samson, Andrew J., Bollan, Karen A., Huang, Jeffrey, Buckland, Stephen T., and Connolly, Christopher N.

Subjects
INSECT pollinators, NEONICOTINOIDS, NECTAR, CLOTHIANIDIN, IMIDACLOPRID
Abstract

The global decline in the abundance and diversity of insect pollinators could result from habitat loss, disease, and pesticide exposure. The contribution of the neonicotinoid insecticides (e.g., clothianidin and imidacloprid) to this decline is controversial, and key to understanding their risk is whether the astonishingly low levels found in the nectar and pollen of plants is sufficient to deliver neuroactive levels to their site of action: the bee brain. Here we show that bumblebees (Bombus terrestris audax) fed field levels [10 nM, 2.1 ppb (w/w)] of neonicotinoid accumulate between 4 and 10 nM in their brains within 3 days. Acute (minutes) exposure of cultured neurons to 10 nM clothianidin, but not imidacloprid, causes a nicotinic acetylcholine receptor-dependent rapid mitochondrial depolarization. However, a chronic (2days) exposure to 1 nM imidacloprid leads to a receptor-dependent increased sensitivity to a normally innocuous level of acetylcholine, which now also causes rapid mitochondrial depolarization inneurons. Finally, colonies exposed to this level of imidacloprid show deficits in colony growth and nest condition compared with untreated colonies. These findings provide a mechanistic explanation for the poor navigation and foraging observed in neonicotinoid treated bumblebee colonies. [ABSTRACT FROM AUTHOR]

Published
2015
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45. Predicting Multivariate Abundances

Author

Warton, David I., Robinson, Andrew P., Series Editor, Buckland, Stephen T., Series Editor, Reich, Peter, Series Editor, McCarthy, Michael, Series Editor, and Warton, David I

Published
2022
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46. Closing Advice

Author

Warton, David I., Robinson, Andrew P., Series Editor, Buckland, Stephen T., Series Editor, Reich, Peter, Series Editor, McCarthy, Michael, Series Editor, and Warton, David I

Published
2022
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47. Studying Co-occurrence Patterns

Author

Warton, David I., Robinson, Andrew P., Series Editor, Buckland, Stephen T., Series Editor, Reich, Peter, Series Editor, McCarthy, Michael, Series Editor, and Warton, David I

Published
2022
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49. Allometric Line Fitting

Author

Warton, David I., Robinson, Andrew P., Series Editor, Buckland, Stephen T., Series Editor, Reich, Peter, Series Editor, McCarthy, Michael, Series Editor, and Warton, David I

Published
2022
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