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Abstract: Megafauna strongly affect vegetation structure and composition, often leading to management concern. However, the extent of their influence across large scales and varying ecosystems remains largely unknown. Using high resolution airborne Light Detection and Ranging (LiDAR), we investigated landscape‐scale changes in vegetation height and three‐dimensional (3D) structure across landscapes of varying elephant densities and presence over time, and in response to surface water distribution and terrain variability in the heavily managed thicket biome of the Addo Elephant National Park, South Africa. Elephants caused up to a fourfold reduction in vegetation height and altered the vertical profile, but increased vegetation height variability. Vegetation height also increased with elevation and distance from water, particularly in areas that elephants had long occupied at high densities. Slope had opposing effects on vegetation height, with height increasing with slope in areas long exposed to elephants, but decreasing where elephants had only recently been granted access. Our results suggest that elephants are the primary agents of vegetation change in this ecosystem, but that the strength of their effects varies across the landscape, enabling management to use water and terrain as mitigation tools. We further highlight the necessity of landscape‐level experimental studies on megafaunal effects to untangle mechanisms and establish causality. [ABSTRACT FROM AUTHOR]

Over four decades, the Albany Bulb in the San Francisco Bay Area, California, United States of America metamorphosed from a dumpsite to a thicket harbouring a clandestine community. Since the forced decampment of this spontaneous society, the site has endured as a living ruin that continues to inspire the explorative impulses of visitors. While residual structures and decaying scrap-sculptures represent the tangible face of the site and its heterotopic past, more nuanced underlying landscape phenomena ground this cultural legacy. In exploring these phenomena, this paper offers a counterpoint to the tendency to engage with wastelands programmatically and pictorially while overlooking the influence of the corporeal landscape. The emergent nature of these phenomena suggests that the agency of design might circumvent typically fraught interactions with undesigned waste-scapes by assuming characteristics of the gardener. [ABSTRACT FROM AUTHOR]

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The article presents discussion of the archaeological excavation of an Early Modern hunting thicket in the area of Roissy-en-France, France. Details are given describing the ruins and remains of ditches and sunken constructions of the area. Discussion is then provided explaining the formations as an early agricultural plantation space for small game hunting. Additional information is then given relating the features of the practices and usage of such thickets in France between the 16th and 18th centuries.

Populations of a number of taxa associated with shrublands, early-successional forests, and other disturbance-generated habitats (collectively referred to as thickets) are declining in the northeastern United States. To assure that species dependent on thicket habitats persist, intervention is warranted. However, conservationists concerned with the status of thicket-dependent species are confronted with two important questions. How much habitat is needed? And how should these habitats be distributed? Natural disturbance regimes have been recommended as a baseline that managers should consider while providing thicket habitats. Within the Northeast, historic disturbance regimes varied substantially among forest types. Coastal regions were characterized by extensive barrens where regular and often times large-scale disturbances that resulted in >15% of the area being covered by regenerating forest stands. Among inland forests, natural disturbances were usually small and resulted in seedling-sapling stands and beaver (Castor canadensis) impoundments covering <6% of the area. Under these conditions, thicket-affiliated species were probably distributed in small, disjunct populations that shifted in space and time. Current efforts to maintain thicket habitats must deal with a range of current land-uses and a legacy of historic uses. Additionally, the effectiveness of management protocols that mimic natural disturbances is limited among many forests. Increasing ownership parcelization, a relatively young forest, and landscape fragmentation substantially reduce the practicality and suitability of small-scale disturbances for generating thicket habitats. Large, clustered patches may be more practical and beneficial, especially in urbanized landscapes. In rural areas, silvicultural manipulations should be applied on a “sliding scale” relative to forest age. Timber harvests that emulate the range of variability of natural disturbances may become appropriate in these areas as forest stands mature. Addressing the needs of thicket-dependent species in the northeastern United States will require creativity, a willingness to explore a variety of solutions, and public support. [Copyright &y& Elsevier]

Between 1980 and 1996, 32 occurrences of Callophrys henrici were discovered to the south and east of Ottawa in regions of sand, loam, peat and limestone on abandoned farmlands. The habitats ranged from openings in Glossy Buckthorn (Rhamnus frangula) thickets to openings and clearings in second growth woodland mostly of poplars (Populus spp.) and/or Cedar (Thuja occidentalis). In most cases the sites had been open farmlands, mostly pastures, 10-70 years ago. The new occurrences in man-made habitats are within a landscape that was largely unoccupied by C. henrici previously, and they represent a 7-fold increase in the number of occurrences in the local area, associated with a several-fold increase in suitable habitat. The association with Glossy Buckthorn was further established through successful rearing of larvae tonormal adults. With the capability of using abandoned farmlands, andthe continuing spread of the introduced Glossy Buckthorn, the previously uncommon and local C. henrici may become a much more common butterfly in Ontario over the next few decades. [ABSTRACT FROM AUTHOR]