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Ecological 'surprises' are defined as unexpected findings about the natural environment. They are critically important in ecology because they are catalysts for questioning and reformulating views of the natural world, help shape assessments of the veracity of a priori predictions about ecological trends and phenomena, and underpin questioning of effectiveness of resource management. Despite the importance of ecological surprises, major gaps in understanding remain about how studies might be done differently or done better to improve the ability to identify them. We outline the kinds of ecological surprises that have arisen from long-term research programs that we lead in markedly different ecosystems around the world. Based on these case studies, we identify important lessons to guide both existing studies and new investigations to detect ecological surprises more readily, better anticipate unusual ecological phenomena, and take proactive steps to plan for and alleviate 'undesirable' ecological surprises. Some of these lessons include: (i) maintain existing, and instigate new, long-term studies; (ii) conduct a range of kinds of parallel and concurrent research in a given target area; (iii) better use past literature and conceptual models of the target ecosystem in posing good questions and developing hypotheses and alternative hypotheses; and (iv) increase the capacity for ecological research to take advantage of opportunities arising from major natural disturbances. We argue that the increased anticipatory capability resulting from these lessons is critical given that ecological surprises may become more prevalent because of climate change and multiple and interacting environmental stressors. discovery doi/ 10.1073/pnas.1015696107

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1523-1739.2008.00997.x Byline: P. GIBBONS (*[dagger][dagger]), D. B. LINDENMAYER (*), J. FISCHER (*), A. D. MANNING (*), A. WEINBERG ([dagger]), J. SEDDON ([double dagger]), P. RYAN (s.), G. BARRETT (s.) Keywords: agricultural-landscape trees; management of scattered trees; paddock trees; recruitment; scattered-tree ecosystems; set-aside forest; tree decline; tree patches Abstract: Abstract: Mature trees scattered throughout agricultural landscapes are critical habitat for some biota and provide a range of ecosystem services. These trees are declining in intensively managed agricultural landscapes globally. We developed a simulation model to predict the rates at which these trees are declining, identified the key variables that can be manipulated to mitigate this decline, and compared alternative management proposals. We used the initial numbers of trees in the stand, the predicted ages of these trees, their rate of growth, the number of recruits established, the frequency of recruitment, and the rate of tree mortality to simulate the dynamics of scattered trees in agricultural landscapes. We applied this simulation model to case studies from Spain, United States, Australia, and Costa Rica. We predicted that mature trees would be lost from these landscapes in 90-180 years under current management. Existing management recommendations for these landscapes-which focus on increasing recruitment-would not reverse this trend. The loss of scattered mature trees was most sensitive to tree mortality, stand age, number of recruits, and frequency of recruitment. We predicted that perpetuating mature trees in agricultural landscapes at or above existing densities requires a strategy that keeps mortality among established trees below around 0.5% per year, recruits new trees at a rate that is higher than the number of existing trees, and recruits new trees at a frequency in years equivalent to around 15% of the maximum life expectancy of trees. Numbers of mature trees in landscapes represented by the case studies will decline before they increase, even if strategies of this type are implemented immediately. This decline will be greater if a management response is delayed. Abstract (Spanish): El Futuro de Arboles Dispersos en Paisajes Agricolas Resumen: Los arboles dispersos en paisajes agricolas son habitat critico para la biota y proporcionan una variedad de servicios ecologicos. Estos arboles estan declinando globalmente en paisajes agricolas manejados intensivamente. Desarrollamos un modelo de simulacion para predecir las tasas a las que estan declinando estos arboles, identificamos las principales variables que pueden ser manipuladas para mitigar esta declinacion y comparamos propuestas de manejo alternativas. Utilizamos el numero inicial de arboles en el sitio, las edades de estos arboles, su tasa de crecimiento, el numero de individuos reclutados, la frecuencia de reclutamiento y la tasa de mortalidad de arboles para simular la dinamica de arboles dispersos en paisajes agricolas. Aplicamos este modelo a estudios de caso de Espana, Estados Unidos, Australia y Costa Rica. Pronosticamos que los arboles maduros se perderan de estos paisajes entre 90 y 180 anos bajos las condiciones de manejo actuales; las recomendaciones de manejo existentes - enfocadas en el incremento del reclutamiento - no cambiarian esta tendencia. Mediante la simulacion de escenarios representando observaciones que abarcan todos los estudios de caso y una gama de opciones de manejo pudimos hacer recomendaciones genericas sobre el manejo de arboles dispersos en paisajes agricolas. La perdida de arboles maduros dispersos fue mas sensible a la mortalidad de arboles, edad del sitio, numero de reclutas y frecuencia de reclutamiento. Predecimos que la perpetuacion de arboles maduros en paisajes agricolas en o por encima de las densidades existentes requiere de una estrategia que mantenga la mortalidad de arboles establecidos por debajo de 0.5% por ano, que reclute arboles a una tasa mayor que el numero de arboles existentes y reclute arboles nuevos en una frecuencia en anos equivalente a alrededor de 15% de la esperanza de vida maxima de los arboles. Sin embargo, el numero de arboles maduros en los paisajes representados por los estudios de caso declinara antes de incrementar, aun si estrategias de este tipo son implementadas inmediatamente. Esta declinacion sera mayor si se posterga una respuesta de manejo. Author Affiliation: (*)The Fenner School of Environment and Society, Building 43, The Australian National University, Canberra, ACT 0200, Australia ([dagger])Science and Research Division, NSW Department of Primary Industries, P.O. Box 100, Beecroft, NSW 2119, Australia ([double dagger])Department of Environment and Conservation (NSW), G.P.O. Box 260, Canberra, ACT 2601, Australia (s.)CSIRO Sustainable Ecosystems, G.P.O. Box 260, Canberra, ACT 2601, Australia Article History: Paper submitted June 26, 2007; revised manuscript accepted March 3, 2008. Article note: ([dagger][dagger]) email philip.gibbons@anu.edu.au

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.2007.0030-1299.16087.x Byline: F. J. L. Kraaijeveld-Smit, D. B. Lindenmayer, A. C. Taylor, C. MacGregor, B. Wertheim Abstract: There are strong links between habitat fragmentation, population size and genetic structure. However, to fully understand the long-term effects of fragmentation on population viability, it is necessary to first understand the relationship between life history traits and genetic characteristics in un-fragmented habitats. This is best done through comparing patterns of genetic diversity in sympatric species, since relative data may be maximally informative. We compared genetic structure and diversity among three sympatric small mammals - of which two were marsupial species - over a small spatial scale ( Article History: Manuscript Accepted 8 June 2007 Article note: F. J. L. Kraaijeveld-Smit (f.j.l.kraaijeveld@biology.leidenuniv.nl), Dept of Zoology, Univ. of Melbourne, VIC 3010, Australia and Animal Ecology, IBL, Kaiserstraat 63, Leiden Univ., Postbus 9516, Leiden, the Netherlands. - D. B. Lindenmayer and C. MacGregor, Fenner School for the Environment and Society, The Australian National Univ., Canberra, ACT 2000, Australia. - A. C. Taylor, Australian Centre for Biodiversity: Analysis, Policy and Management, School of Biological Sciences, Monash Univ., Clayton, VIC 3800, Australia. - B. Wertheim, Dept of Biology, Univ. College London, Gower Street. London, UK, WC1E 6BT.

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1523-1739.2006.00497.x Byline: D.B. LINDENMAYER (*), R.F. NOSS ([dagger]) Keywords: forest management; human disturbance; natural disturbance Abstract: Abstract: We summarize the documented and potential impacts of salvage logging-a form of logging that removes trees and other biological material from sites after natural disturbance. Such operations may reduce or eliminate biological legacies, modify rare postdisturbance habitats, influence populations, alter community composition, impair natural vegetation recovery, facilitate the colonization of invasive species, alter soil properties and nutrient levels, increase erosion, modify hydrological regimes and aquatic ecosystems, and alter patterns of landscape heterogeneity. These impacts can be assigned to three broad and interrelated effects: (1) altered stand structural complexity; (2) altered ecosystem processes and functions; and (3) altered populations of species and community composition. Some impacts may be different from or additional to the effects of traditional logging that is not preceded by a large natural disturbance because the conditions before, during, and after salvage logging may differ from those that characterize traditional timber harvesting. The potential impacts of salvage logging often have been overlooked, partly because the processes of ecosystem recovery after natural disturbance are still poorly understood and partly because potential cumulative effects of natural and human disturbance have not been well documented. Ecologically informed policies regarding salvage logging are needed prior to major natural disturbances so that when they occur ad hoc and crisis-mode decision making can be avoided. These policies should lead to salvage-exemption zones and limits on the amounts of disturbance-derived biological legacies (e.g., burned trees, logs) that are removed where salvage logging takes place. Finally, we believe new terminology is needed. The word salvage implies that something is being saved or recovered, whereas from an ecological perspective this is rarely the case. Abstract (Spanish): Cosecha de Salvamento, Procesos Ecologicos y Conservacion de la Biodiversidad Resumen: Resumimos los impactos documentados y potenciales de la cosecha de salvamento - una forma de cosecha de madera que remueve arboles y otros materiales biologicos despues de una perturbacion natural. Tales operaciones pueden reducir o eliminar legados biologicos, modificar habitats post perturbacion, influir en poblaciones, alterar la composicion de comunidades, impedir la recuperacion de la vegetacion natural, facilitar la colonizacion de especies invasoras, alterar las propiedades del suelo y de niveles de nutrientes, incrementar la erosion, modificar regimenes hidrologicos y ecosistemas acuaticos, y alterar patrones de heterogeneidad del paisaje. Estos impactos se pueden asignar a tres efectos amplios e interrelacionados: (1) alteracion de la complejidad estructural del bosque; (2) alteracion de procesos y funciones ecologicas; y (3) alteracion de poblaciones de especies y de la composicion de la comunidad. Algunos impactos pueden ser diferentes a o adicionales a los efectos de la cosecha de madera tradicional que no es precedida de una perturbacion natural severa porque las condiciones antes, durante y despues de la cosecha de salvamento pueden diferir de las que caracterizan a la cosecha de madera tradicional. Los impactos potenciales de la cosecha de salvamento a menudo han sido pasados por alto, en parte porque los procesos de recuperacion del ecosistema despues de una perturbacion natural son poco conocidos y en parte porque los efectos acumulativos potenciales de perturbaciones naturales y humanas no han sido bien documentados. Se requieren politicas ecologicamente informadas para la cosecha de salvamento para que cuando ocurran las perturbaciones naturales se evite la toma de decisiones en situaciones de crisis. Estas politicas deberan establecer zonas exentas de salvamento y limites a las cantidades de legados biologicos derivados de la perturbacion (e. g., arboles quemados, troncos) que son removidos donde se lleva a cabo la cosecha de salvamento. Finalmente, creemos que se requiere una nueva terminologia. La palabra salvamento implica que algo esta siendo salvado o recuperado, y este raramente es el caso desde una perspectiva ecologica. Author Affiliation: (*)Centre for Resource and Environmental Studies, The Australian National University, Canberra, ACT 0200, Australia, emaildavidl@cres.anu.edu.au ([dagger])Department of Biology, University of Central Florida, Orlando, Florida 32816-2368, U.S.A. Article History: Paper submitted November 9, 2005; revised manuscript accepted April 18, 2006.

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1523-1739.2006.00501.x Byline: D.B. LINDENMAYER (*), K. OUGH ([dagger]) Keywords: logging after wildfire; logging impacts on biodiversity; salvage harvesting; southeastern Australia; timber harvesting; wet eucalypt forests Abstract: Abstract: The two major forms of disturbance in the montane ash eucalypt forests of the Central Highlands of Victoria (southeastern Australia) are clearfell logging and unplanned wildfires. Since the 1930s wildfire has been followed by intensive and extensive salvage-logging operations, which may proceed for many years after a wildfire has occurred. Although applied widely, the potential effects of salvage logging on native flora and fauna have been poorly studied. Our data indicate that the abundance of large trees with hollows is significantly reduced in forests subject to salvage harvesting. This has implications for the persistence of an array of such cavity-using vertebrates as the endangered arboreal marsupial, Leadbeater's possum (Gymnobelidues leadbeateri). Salvage logging also reduces the prevalence of multiaged montane ash forests-places that typically support the highest diversity of arboreal marsupials and forest birds. Limited research has been conducted on the effects of salvage logging on plants; thus, we constructed hypotheses about potential impacts for further testing based on known responses to clearfell logging and key life history attributes. We predict many species, such as vegetatively resprouting tree ferns, will decline, as they do after clearfelling. We also suggest that seed regenerators, which typically regenerate well after fire or conventional clearfelling, will decline after salvage logging because the stimulation for germination (fire) takes place prior to mechanical disturbance (logging). Understory plant communities in salvage-logged areas will be dominated by a smaller suite of species, and those that are wind dispersed, have viable soil-stored seed remaining after salvage logging, or have deep rhizomes are likely to be advantaged. We recommend the following improvements to salvage-logging policies that may better incorporate conservation needs in Victorian montane ash forests: (1) exemption of salvage logging from some areas (e.g., old-growth stands and places subject to only partial stand damage); (2) increased retention of biological legacies on burned areas through variations in the intensity of salvage logging; and (3) reduction in the levels of physical disturbance on salvage-logged areas, especially through limited seedbed preparation and mechanical disturbance. Abstract (Spanish): Cosecha de Salvamento en los Bosques Montanos de Eucalipto del Altiplano Central de Victoria y Sus Impactos Potenciales sobre la Biodiversidad Resumen: La cosecha de madera y el fuego no controlado son las dos formas principales de perturbacion en los bosques montanos de eucalipto en el Altiplano Central de Victoria (sureste de Australia). Desde la decada de 1930, los incendios no controlados son seguidos por operaciones intensivas y extensivas de salvamento de madera, que pueden proceder por muchos anos despues de que ocurrio el fuego no controlado. Aunque aplicados ampliamente, los efectos potenciales de la cosecha de salvamento sobre la flora y fauna nativa han sido escasamente estudiados. Nuestros datos indican que la abundancia de arboles grandes con oquedades se reduce significativamente en bosques sujetos a la cosecha de salvamento. Esto tiene implicaciones para la persistencia de un conjunto de vertebrados que utilizan oquedades, como el marsupial arboreo Gymnobelidues leadbeateri en peligro. La cosecha de salvamento tambien reduce la prevalencia de bosques montanos de edades multiples - sitios que tipicamente soportan la mayor diversidad de marsupiales arboreos y aves de bosque. La investigacion sobre los efectos de la cosecha de salvamento sobre las plantas es limitada, por lo tanto, construimos hipotesis sobre los impactos potenciales para probarlas posteriormente con base en respuestas conocidas a la cosecha de madera y en atributos clave de las historias de vida. Predecimos que muchas especies, como helechos arboreos con reproduccion vegetativa, declinaran, tal como sucede despues de la cosecha de madera. Tambien sugerimos que los regeneradores por semilla, que tipicamente regeneran bien despues del fuego o la cosecha de madera, declinaran despues de la cosecha de salvamento porque la estimulacion para la germinacion (fuego) se lleva a cabo antes de la perturbacion mecanica (cosecha de madera). Las comunidades de plantas de sotobosque en areas con cosecha de salvamento estaran dominadas por un conjunto menor de especies, y es probable que sean favorecidas aquellas que son dispersadas por el viento, que tienen semillas viables almacenadas en el suelo despues de la cosecha de salvamento o que tienen rizomas profundos. Recomendamos las siguientes mejoras a las politicas de cosecha de salvamento que pueden incorporar las necesidades de conservacion en los bosques montanos de Victoria: (1) exencion de cosecha de salvamento en algunas areas (e.g., bosques maduros y sitios sujetos solo a danos parciales); (2) incremento en la retencion de legados biologicos en areas quemadas por medio de variaciones en la intensidad de la cosecha de salvamento; y (3) reduccion de los niveles de perturbacion fisica sobre las areas con cosecha de salvamento, especialmente la preparacion limitada de semilleros y la perturbacion mecanica. Author Affiliation: (*)Centre for Resource and Environmental Studies, The Australian National University, Canberra, ACT 0200, Australia, emaildavidl@cres.anu.edu.au ([dagger])Arthur Rylah Institute for Environmental Research, Department of Sustainability and Environment, 123 Brown Street, Heidelberg, Victoria, 3084 Australia Article History: Paper submitted September 24, 2004; revised manuscript accepted April 11, 2006.

In ecology, populations may be linked conceptually with landscapes through habitat and spatial population models. Usually, these models deal with single species and treat a range of uncertainties implicitly and explicitly. They assist managers in testing different management scenarios and making strategic decisions. Landscape pattern analysis was the first attempt to deal with multiple species, and it led to a range of landscape management strategies. Advances in landscape ecology, driven largely by the pragmatic needs of conservation, are building approaches to multispecies management that have stronger ecological foundations. However, their treatment of uncertainty is in its infancy. In this paper, we provide examples to illustrate some of these issues. We conclude that one of the most important sources of uncertainty is the choice of the modeling frame. We recommend that landscape planners use different kinds of models, identify important sources of uncertainty that may affect planning decisions, and seek options that are likely to result in tolerable outcomes, despite uncertainty. Key words: decision theory; focal species; habitat maps; landscape ecology; metapopulations; nested subsets; reserve design; spatial pattern.

The concept of continua in nature and the concept of Umwelt, which is related to individual species perception and response, are discussed to explain the landscapes and landscape ecology. It is found that the landscape continuum model having the continua and species perception could assist in determining ways to reflect the multi-faceted reality.

The focal-species approach involves the identification of a suite of species targeted for the management of threatening processes and vegetation-restoration efforts. The focal-species has potential limitations therefore a mix of different landscapes should be adopted in any given landscape and between different landscapes to spread risk of failure of any one approach which will raise awareness about the potential limitations of the focal-species approach.