The Experts below are selected from a list of 939 Experts worldwide ranked by ideXlab platform
Michelle A Jusino - One of the best experts on this subject based on the ideXlab platform.
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Heart Rot hotel fungal communities in red cockaded woodpecker excavations
Fungal Ecology, 2015Co-Authors: Michelle A Jusino, Daniel L Lindner, Mark T Banik, Jeffrey R WaltersAbstract:Tree-cavity excavators such as woodpeckers are ecosystem engineers that have potentially complex but poorly documented associations with wood decay fungi. Fungi facilitate cavity excavation by preparing and modifying excavation sites for cavity excavators. Associations between fungi and endangered red-cockaded woodpeckers (RCWs) are particularly interesting because these are the only birds that specialize in excavating into the Heartwood of living pines, a process that takes years to complete. Using molecular methods, we examined fungal communities in complete and incomplete RCW excavations, and non-cavity control trees. In addition to finding a high diversity of fungi, we found three groupings of fungal communities corresponding to the three groups of trees sampled. We show that trees selected for cavity excavation by RCWs are infected by distinct fungal communities, and propose two hypotheses to explain this outcome: the bird facilitation hypothesis and the tree selection hypothesis.
Kristina L Cockle - One of the best experts on this subject based on the ideXlab platform.
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linking fungi trees and hole using birds in a neotropical tree cavity network pathways of cavity production and implications for conservation
Forest Ecology and Management, 2012Co-Authors: Kristina L Cockle, Kathy Martin, Gerardo RobledoAbstract:Abstract In tropical forests and savannahs worldwide, hundreds of species of cavity-nesting vertebrates depend, for nesting and roosting, on the limited resource of tree cavities. These cavities are produced by avian excavators and decay processes in trees infected with Heart-Rot fungi. Conservation of cavity-nesting communities requires a solid understanding of how cavities are produced and used; however, no studies have examined the interactions among cavity producers and consumers in tropical forest. Moreover, the role of Heart-Rot fungi in producing cavities for nesting vertebrates has not been studied at the community level anywhere in the world. We studied a “nest web”, or interspecific hierarchical network of cavity producers and users, in the Atlantic forest, a tropical biodiversity hotspot of high conservation concern, in South America. We searched for active nests in tree cavities from 2006 to 2010, and determined the species of trees, Heart-Rot fungi, and avian excavators that produced the cavities and the species of non-excavating birds (secondary cavity-nesters) that used them. We identified two main pathways that produced the cavities used by non-excavators. Thirty-three percent of passerine nests and 9% of non-passerine nests were in cavities produced by avian excavators; the majority of nests (83% overall) were in cavities produced directly by decay processes including mechanical damage, invertebrate damage, and fungal decay (non-excavated cavities). Trees bearing cavities produced by excavators were 2/3 the diameter of those bearing non-excavated cavities, had eight times the odds of being dead, and 37 times the odds of being colonized with Heart-Rot fungi in the family Polyporaceae s.l. (vs. Hymenochaetaceae that were dominant in trees bearing non-excavated cavities). In contrast to nest webs in North America, the Atlantic Forest nest web was characterized by high diversity and evenness of interactions, whereby non-excavating bird species did not depend on any one species of tree, fungus or avian excavator for cavity production. The community should thus be relatively robust to extinctions of cavity producing species. However, on-going destruction of large living trees with non-excavated cavities is likely to disrupt the major pathway of cavity production, and may result in a shift toward greater dependence on excavated cavities in smaller, dead trees, infected with Polyporaceae and occupied primarily by passerine birds. To conserve cavity-using communities in tropical forests, governments and certification agencies should implement policies that result in the retention of several large living trees per hectare.
Jeffrey R Walters - One of the best experts on this subject based on the ideXlab platform.
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Heart Rot hotel fungal communities in red cockaded woodpecker excavations
Fungal Ecology, 2015Co-Authors: Michelle A Jusino, Daniel L Lindner, Mark T Banik, Jeffrey R WaltersAbstract:Tree-cavity excavators such as woodpeckers are ecosystem engineers that have potentially complex but poorly documented associations with wood decay fungi. Fungi facilitate cavity excavation by preparing and modifying excavation sites for cavity excavators. Associations between fungi and endangered red-cockaded woodpeckers (RCWs) are particularly interesting because these are the only birds that specialize in excavating into the Heartwood of living pines, a process that takes years to complete. Using molecular methods, we examined fungal communities in complete and incomplete RCW excavations, and non-cavity control trees. In addition to finding a high diversity of fungi, we found three groupings of fungal communities corresponding to the three groups of trees sampled. We show that trees selected for cavity excavation by RCWs are infected by distinct fungal communities, and propose two hypotheses to explain this outcome: the bird facilitation hypothesis and the tree selection hypothesis.
Gilberto Pasinelli - One of the best experts on this subject based on the ideXlab platform.
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Heart Rot as a key factor for cavity tree selection in the black woodpecker
Forest Ecology and Management, 2012Co-Authors: Volker Zahner, Luis Sikora, Gilberto PasinelliAbstract:Cavity nesting birds invest considerable time and effort into the construction of nests. The investment can be particularly high for species such as the black woodpecker (Dryocopus martius) that selects living trees as nest substrates. However, the investment may be reduced if fungal Rot is present to help soften the wood. We used Resistograph drills to objectively assess fungal decay and tested whether black woodpeckers preferred trees with Heart Rot as sites for cavity starts. In doing so we also examined the distribution of fungal decay across the tree radius, analysed location of cavity starts with respect to proximity to Heart Rot, and evaluated wood condition at fresh and old cavity starts. Heart Rot was significantly more common in beeches (Fagus sylvatica) with cavity starts than in random reference beeches. Fungal decay was not evenly distributed across the tree radius, but was more prevalent both in the central and outer thirds than in the middle third. Distance to Heart Rot was smaller from cavity starts than from random drills, suggesting a preference to initiate cavities close to Heart Rot. Wood density at fresh cavity starts was significantly higher than at old cavity starts. Collectively, these findings imply that black woodpeckers prefer to excavate cavity starts in beeches with Heart Rot, which the woodpeckers can detect based on cues unavailable to humans. The decay is reducing the energy expenditure of the black woodpecker and is a part of the long time excavation strategy. The cavity starts are an important factor in the process of excavating the large black woodpecker cavities in beech that enhance biodiversity in managed forests. Future studies should attempt to uncover the mechanisms woodpeckers use in selecting the locations of cavity starts.
Gerardo Robledo - One of the best experts on this subject based on the ideXlab platform.
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linking fungi trees and hole using birds in a neotropical tree cavity network pathways of cavity production and implications for conservation
Forest Ecology and Management, 2012Co-Authors: Kristina L Cockle, Kathy Martin, Gerardo RobledoAbstract:Abstract In tropical forests and savannahs worldwide, hundreds of species of cavity-nesting vertebrates depend, for nesting and roosting, on the limited resource of tree cavities. These cavities are produced by avian excavators and decay processes in trees infected with Heart-Rot fungi. Conservation of cavity-nesting communities requires a solid understanding of how cavities are produced and used; however, no studies have examined the interactions among cavity producers and consumers in tropical forest. Moreover, the role of Heart-Rot fungi in producing cavities for nesting vertebrates has not been studied at the community level anywhere in the world. We studied a “nest web”, or interspecific hierarchical network of cavity producers and users, in the Atlantic forest, a tropical biodiversity hotspot of high conservation concern, in South America. We searched for active nests in tree cavities from 2006 to 2010, and determined the species of trees, Heart-Rot fungi, and avian excavators that produced the cavities and the species of non-excavating birds (secondary cavity-nesters) that used them. We identified two main pathways that produced the cavities used by non-excavators. Thirty-three percent of passerine nests and 9% of non-passerine nests were in cavities produced by avian excavators; the majority of nests (83% overall) were in cavities produced directly by decay processes including mechanical damage, invertebrate damage, and fungal decay (non-excavated cavities). Trees bearing cavities produced by excavators were 2/3 the diameter of those bearing non-excavated cavities, had eight times the odds of being dead, and 37 times the odds of being colonized with Heart-Rot fungi in the family Polyporaceae s.l. (vs. Hymenochaetaceae that were dominant in trees bearing non-excavated cavities). In contrast to nest webs in North America, the Atlantic Forest nest web was characterized by high diversity and evenness of interactions, whereby non-excavating bird species did not depend on any one species of tree, fungus or avian excavator for cavity production. The community should thus be relatively robust to extinctions of cavity producing species. However, on-going destruction of large living trees with non-excavated cavities is likely to disrupt the major pathway of cavity production, and may result in a shift toward greater dependence on excavated cavities in smaller, dead trees, infected with Polyporaceae and occupied primarily by passerine birds. To conserve cavity-using communities in tropical forests, governments and certification agencies should implement policies that result in the retention of several large living trees per hectare.
