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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2008.11.027 Byline: Stuart Jones (a), Peter Lacey (b), Terry Walshe (a) Abstract: Lake Toolibin, an ephemeral lake in the agricultural zone of Western Australia, is under threat from secondary salinity due to land clearance throughout the catchment. The lake is extensively covered with native vegetation and is a Ramsar listed wetland, being one of the few remaining significant migratory bird habitats in the region. Currently, inflow with salinity greater than 1000 mg/L TDS is diverted from the lake in an effort to protect sensitive lakebed vegetation. However, this conservative threshold compromises the frequency and extent of lake inundation, which is essential for bird breeding. It is speculated that relaxing the threshold to 5000 mg/L may pose negligible additional risk to the condition of lakebed vegetation. To characterise the magnitude of improvement in the provision of bird breeding habitat that might be generated by relaxing the threshold, a dynamic water and salt balance model of the lake was developed and implemented using Monte Carlo simulation. Results from best estimate model inputs indicate that relaxation of the threshold increases the likelihood of satisfying habitat requirements by a factor of 9.7. A second-order Monte Carlo analysis incorporating incertitude generated plausible bounds of [2.6, 37.5] around the best estimate for the relative likelihood of satisfying habitat requirements. Parameter-specific sensitivity analyses suggest the availability of habitat is most sensitive to pan evaporation, lower than expected inflow volume, and higher than expected inflow salt concentration. The characterisation of uncertainty associated with environmental variation and incertitude allows managers to make informed risk-weighted decisions. Author Affiliation: (a) School of Botany, The University of Melbourne, VIC 3010, Australia (b) Western Australia Department of Environment and Conservation, Hough Street, Narrogin, WA 6312, Australia Article History: Received 13 March 2008; Revised 13 October 2008; Accepted 22 November 2008

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1365-2745.2008.01379.x Byline: Tomas A. Carlo (1), Juan M. Morales (2) Keywords: bird movement; dispersal kernel; frugivory; plant fitness; simulation model Abstract: Summary Frugivores disperse the seeds of the majority of woody plant species world-wide. Thus, insights on how frugivores influence the dispersal of plants and the variability of this process are crucial for understanding plant population dynamics in a rapidly changing world. We used a spatially explicit, stochastic, individual-based model that simulates fruit-removal and seed dispersal by birds to assess bird density, landscape and neighbourhood effects on the inequalities of within-population fruit-removal rates and seed dispersal. We also compared model predictions with spatially-explicit field data. In our simulations, bird density had a strong effect on the distribution of fruit-removal rates creating large inequalities among plants. Also, for equal bird densities, inequalities increased with the landscape level aggregation of plants. Fruit removal increased with increasing plant neighbourhood density although there was a tendency to decline at the highest densities. Neighbourhood density also changed average dispersal distances, but with shorter distances at higher densities. Plants with few neighbours not only had longer distance dispersal but also a larger variance in seed rain across distances than plants with ten or more neighbours. These relationships between neighbourhood density and fruit removal and dispersal distance were scale-dependent with a peak in correlations at 150-m radius. Similar to model predictions, field data shows an inverse relationship between dispersal distances (inferred from bird movements) and fruiting neighbourhood density. Also, fruit-removal rates observed in the field show large numbers of plants receiving little or zero fruit-removal. Fruit-removal rate distributions were statistically indistinguishable between the simulation and field data. But, distributions were strikingly different from two alternative models that lacked spatial effects. Synthesis. Our model and field data show that as fruiting plants become aggregated, inequalities in fruit-removal rates increase and seed dispersal distance decreases. Both of these processes could help create and maintain plant aggregation and affect genetic structuring. The model also predicts that small-scale neighbourhood effects can be controlled by large-scale processes such as overall frugivore abundance and landscape-level plant aggregation. Most importantly, both simulations and field data shows an interaction between plant spatial pattern and bird foraging, which results in neighbourhood-specific dispersal and rates of fruit removal. Author Affiliation: (1)Department of Ecology and Evolutionary Biology, University of Colorado, Boulder CO 80301, USA; and (2)Laboratorio Ecotono, INIBIDMA-CONICET, Universidad Nacional del Comahue; 8400 Bariloche, Argentina Article History: Received 2 August 2007; accepted 11 March 2008 Handling Editor: Ran Nathan Article note: (*) Correspondence author. Department of Biology, the Pennsylvania State University, University Park, PA 16802. E-mail: dendrophthora@gmail.com

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2006.07.001 Byline: Robin M. Fuller (a), Bernard J. Devereux (a), Simon Gillings (b), Ross A. Hill (c), Gabriel S. Amable (a) Keywords: Bird; Habitat; Map; Remote sensing; Biodiversity; Landscape; Ecology; Modelling Abstract: This paper develops a comprehensive and objective picture of bird distributions relative to habitats across Britain. Bird species presence/absence data from an extensive field survey and habitat data from the remotely sensed UK Land Cover Map 2000 were analysed in 36,920 tetrads (2kmx2km) across Britain (a 65% sample of Britain's c. 240000km.sup.2). Cluster analysis linked birds to generalised landscapes based on distinctive habitat assemblages. Maps of the clusters showed strong regional patterns associated with the habitat assemblages. Cluster centroid coordinates for each bird species and each habitat were combined across clusters to derive individualised bird-habitat preference indices and examine the importance of individual habitats for each bird species. Even rare species and scarce habitats showed successful linkages. Results were assessed against published accounts of bird-habitat relations. Objective corroboration strongly supported the associations. Relatively scarce coastal and wetland habitats proved particularly important for many birds. However, extensive arable farmland and woodland habitats were also favoured by many species, despite reported declines in bird numbers in these habitats. The fact that habitat-specialists do not or cannot move habitat is perhaps a reason for declining numbers where habitats have become unsuitable. This study showed that there are unifying principles determining bird-habitat relations which apply and can be quantified at the national scale, and which corroborate and complement the cumulative knowledge of many and varied surveys and ecological studies. This 'generality' suggests that we may be able, reliably and objectively, to integrate and scale up such disparate studies to the national scale, using this generalised framework. It also suggests the potential for a landscape ecology approach to bird-habitat analyses. Such developments will be important steps in building models to develop and test the sustainable management of landscapes for birds. Author Affiliation: (a) University of Cambridge, Unit for Landscape Modelling, Sir William Hardy Building, Downing Site, Tennis Court Road, Cambridge CB2 1QB, UK (b) British Trust for Ornithology, The Nunnery, Thetford, Norfolk IP24 2PU, UK (c) Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire PE28 2LS, UK Article History: Received 6 July 2005; Revised 8 May 2006; Accepted 12 July 2006

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1523-1739.2006.00378.x Byline: PETER W.J. BAXTER (*[dagger][double dagger][double dagger]), MICHAEL A. McCARTHY ([dagger]*), HUGH P. POSSINGHAM ([double dagger]), PETER W. MENKHORST (s.), NATASHA McLEAN (s.**) Keywords: conservation; elasticity; marginal costs; marginal efficiency; optimization; perturbation analysis; population management; stochastic model Abstract: Abstract: Traditional sensitivity and elasticity analyses of matrix population models have been used to inform management decisions, but they ignore the economic costs of manipulating vital rates. For example, the growth rate of a population is often most sensitive to changes in adult survival rate, but this does not mean that increasing that rate is the best option for managing the population because it may be much more expensive than other options. To explore how managers should optimize their manipulation of vital rates, we incorporated the cost of changing those rates into matrix population models. We derived analytic expressions for locations in parameter space where managers should shift between management of fecundity and survival, for the balance between fecundity and survival management at those boundaries, and for the allocation of management resources to sustain that optimal balance. For simple matrices, the optimal budget allocation can often be expressed as simple functions of vital rates and the relative costs of changing them. We applied our method to management of the Helmeted Honeyeater (Lichenostomus melanops cassidix; an endangered Australian bird) and the koala (Phascolarctos cinereus) as examples. Our method showed that cost-efficient management of the Helmeted Honeyeater should focus on increasing fecundity via nest protection, whereas optimal koala management should focus on manipulating both fecundity and survival simultaneously. These findings are contrary to the cost-negligent recommendations of elasticity analysis, which would suggest focusing on managing survival in both cases. A further investigation of Helmeted Honeyeater management options, based on an individual-based model incorporating density dependence, spatial structure, and environmental stochasticity, confirmed that fecundity management was the most cost-effective strategy. Our results demonstrate that decisions that ignore economic factors will reduce management efficiency. Abstract (Spanish): Representacion de Gastos de Administracion en el Analisis de Sensibilidad de Modelos Poblacionales Matriciales Resumen: Los tradicionales analisis de sensibilidad y elasticidad de los modelos poblacionales matriciales han sido utilizados para informar a las decisiones de gestion, pero ignoran los costos economicos de la manipulacion de las tasas vitales. Por ejemplo, la tasa de crecimiento de una poblacion a menudo es mas sensible a los cambios en la tasa de supervivencia de adultos, pero esto no significa que el incremento de esta tasa es la mejor opcion para la gestion de la poblacion porque puede ser mucho mas cara que otras opciones. Para explorar como los gestores deberian optimizar su manipulacion de las tasas vitales, incorporamos el costo del cambio de esas tasas en modelos poblacionales matriciales. Derivamos expresiones analiticas en puntos del parametro espacio en los que los gestores deben alternar entre la gestion de fecundidad y de supervivencia para el balance entre la gestion de la fecundidad y la supervivencia en esos limites y para la asignacion de recursos para sostener ese balance optimo. En matrices simples, la asignacion presupuestaria optima se puede expresar a menudo como funciones simples de las tasas vitales asi como los costos relativos de cambiarlos. Como ejemplos, aplicamos nuestro metodo en la gestion de Lichenostomus melanops cassidix (una ave australiana en peligro) y del koala (Phascolarctos cinereus). Nuestro metodo mostro que la gestion rentable de L. m. cassidix deberia enfocar el incremento de la fecundad por medio de la proteccion de nidos, mientras que la gestion optima del koala deberia centrarse en la manipulacion simultanea de la fecundidad y de la supervivencia. Estos hallazgos son contrarios a las recomendaciones que no consideran a los costos del analisis de elasticidad, que sugeririan centrar la gestion en la supervivencia en ambos casos. Una investigacion posterior de las opciones de gestion de L. m. cassidix, con base en un modelo que incorporo denso dependencia, estructura especial y estocasticidad ambiental, confirmo que la gestion de la fecundidad era la estrategia mas rentable. Nuestros resultados demuestran que las decisiones que ignoran factores economicos reducen la eficiencia de la gestion. Author Affiliation: (*)School of Botany, University of Melbourne, Parkville VIC 3010, Australia ([dagger])Australian Research Centre for Urban Ecology, Royal Botanic Gardens, Melbourne, c/- School of Botany, University of Melbourne, Parkville VIC 3010, Australia ([double dagger])The Ecology Centre, Departments of Zoology and Mathematics, The University of Queensland, Brisbane, QLD 4072, Australia (s.)Department of Sustainability and Environment, PO Box 500, East Melbourne, VIC 3002, Australia (**)Department of Zoology, University of Melbourne, Parkville VIC 3010, Australia Article History: Paper submitted April 7, 2005; revised manuscript accepted for publication July 12, 2005. Article note: ([double dagger][double dagger]) Address for correspondence: School of Integrative Biology, University of Queensland, Brisbane QLD 4072, Australia, email p.baxter@uq.edu.au

Annual local survival of adult Greater Flamingos, Phoenicopterus ruber roseus, breeding at their natal colony in the Camargue (southern France), was studied using ringed birds observed at the colony from 1983 to 1991. Survival and probability of resighting were estimated separately, using capture-recapture models. Because all the birds we observed were nesting, differences in probability of resighting reflect differences in probability of breeding. Winter severity significantly affected survival. Annual local survival was 93% during normal years, but in 1984-1985, following a severe cold spell, survival fell to 76%. Sex and age (range 4 to 14 yr old) had no significant effect on survival. Resighting rates varied between 11% and 88% during the study period. There were significant additive effects of year, sex, and age on resighting rates. The probability of resighting increased with age in both males and females, reflecting the progressive access to regular reproductive status in this population. However, males had a higher probability of being resighted than females, probably due to their higher rates of mate switching and renesting following breeding failure. Key words: accession to reproduction; adult mortality; age-specific breeding probabilities; capture-recapture; cost of reproduction; Greater Flamingo; Phoenicopterus tuber roseus; re-mating; survival; weather effects., INTRODUCTION Variation of survival rates among groups and over time are of major importance for understanding the life history of a species, as well as for developing realistic models of [...]

While several models use total body electrical conductivity (TOBEC) to predict lipid mass of live birds, few studies have examined whether the models are valid with independent data. A new study develops and assesses the performance of such models with independent data collected under controlled conditions. The study of northern bobwhites shows that the use of TOBEC to predict lipid mass can be reliable in some instances but deviations between observed and predicted lipid mass can be large. Other factors influencing body composition may inhibit the development of models that are generally applicable.