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Expanding Shifting Baseline Syndrome to Accommodate Increasing Abundances

Article

Expanding Shifting Baseline Syndrome to Accommodate Increasing Abundances

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Abstract

The shifting baseline syndrome suggests that our perceptions of previous conditions may change over time as ecosystems degrade. Although most discussion of the topic relates to decreasing species abundances, there are several reasons to think that abundances of many species will increase in response to anthropogenic disturbance. For example, increases in abundances of certain species are predicted after the removal of predators, as exotic and invasive species become established, and as habitat generalists proliferate. Because generational amnesia about historic conditions could influence the setting of restoration targets, restoration ecologists should explicitly consider the shifting baseline syndrome in reference to increases in abundances from historic levels.

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... This increasingly means acceptance of ecosystems with few, if any, resident carnivores as normal (Ripple et al., 2014;Vera, 2010). However, shifting baselines will also affect how increases in the abundance of species (e.g. from a historically low 'baseline') are perceived (Steen & Jachowski, 2013). ...
... This is a key area of concern, for pine marten conservation, given that relatively few instances of human-induced mortality could undermine population establishment (Treves et al., 2017). 'Shifting baseline syndrome' appeared to play a role in framing the Concerned Manager perspective of predators, though it related to comparisons with increasing abundance of badgers rather than any broader 'generational amnesia' associated with wildlife decline over time (Steen & Jachowski, 2013). The abundance of badgers in England and Wales has increased markedly since the 1980s (Judge, Wilson, Macarthur, McDonald, & Delahay, 2017), and the badger population within the study area was described by participants associated with Perspective 4 Concerned Manager as being 'out of control', colonizing areas in which they had never before experienced them. ...
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1. Reversing global declines in predator populations is a major conservation objective , though people frequently come into conflict over carnivore conservation. As part of a national recovery programme for the pine marten Martes martes, a protected mesocarnivore in the UK, we used Q-methodology to understand the perspectives of residents living in an area in which a pine marten translocation project was planned. 2. In contrast to binary 'for or against' characterizations of debates surrounding such projects, we identified four perspectives with distinct priorities and concerns. A single perspective, 'Concerned Manager', opposed the translocation and marten recovery more generally, was apprehensive about impacts and favoured traditional predator management practices. Support was characterized by three perspectives: 'Environmental Protectionist', 'Natural Resource Steward' and 'Cautious Pragmatist'. Two explicitly supported the translocation but differed in their priorities: Environmental Protectionist framed marten restoration as an ethical imperative , whereas Natural Resource Steward emphasized ecological and economic benefits. Cautious Pragmatist supported marten recovery, but expressed ambivalence about the translocation. 3. We identified areas of divergence between the four perspectives, particularly surrounding risks posed by martens and need for predator control. We identified two areas of consensus among the four perspectives: support for a biodiverse environment and translocations as a means of achieving this (though this was contingent on the species), and agreement there would be economic and ecological benefits if martens controlled non-native grey squirrels Sciurus carolinensis. 4. We highlight that perspectives on this project were influenced by wider issues of wildlife management and conservation, particularly the impact and management of increasing populations of another mesocarnivore, the badger Meles meles. Negative experiences and perceptions of badgers were germane to the Concerned Manager perspective, and their fear that protected status would preclude marten
... Shifting baselines are known to pervade environmental management globally, due to ongoing climate change and intensifying anthropogenic disturbances [4,5]. Some disturbed systems will unlikely recover to the predisturbance state, whose baselines are shifting concomitantly under additional disturbances. ...
... Certain ecological variables can show a contrasting type of disturbance-induced trajectory to those depicted in [3]; that is, they increase during the period of disturbance ('concave downward') [5], and decrease postdisturbance to eventually reach the predisturbance state. For instance, during a warming-induced coral bleaching event in the Great Barrier Reef, a seaweed (Lobophora variegata) bloom was observed and declined afterwards as corals re-established [7]. ...
... First, the term has been used to describe a form of generational amnesia occurring when knowledge of natural baselines is not passed on from one generation to the next (Huitric, 2005;Sá enz-Arroyo et al., 2005). With scarce intergenerational communication, each new generation has a more biased conception of how much change has undergone the ecosystem, as they assess change relative to baselines that shift with each new generation (Steen and Jachowski, 2013). Second, the term SBS has also been used to describe a type of personal amnesia, where individuals constantly (albeit unconsciously) update their own perception of normality over the course of their lifetime (Simons and Rensink, 2005). ...
... SBS was originally observed in fisheries' sciences, when Pauly (1995) noticed how each generation of fisheries' scientists accepted the fish stock sizes occurring at the beginning of their careers as a baseline to evaluate change, with every new generation updating the baseline even when the stocks had further declined. The concept was rapidly picked up in a number of other disciplines, including cognitive science (Simons and Rensink, 2005), environmental history (Sá enz-Arroyo et al., 2006;Humphries and Winemiller, 2009), restoration ecology (Whipple et al., 2010;Steen and Jachowski, 2013) and ethnobotany (Hanazaki et al., 2013). More recently, the concept has permeated beyond purely academic spheres and it is used even by environmental advocacy groups (Campbell et al., 2009;Shifting Baselines, 2014). ...
... periods when turtles were orders of magnitude more abundant and when they were often the dominant species in an ecosystem by virtue of their large biomass. The current and unaware generation accepts this new reality reduced biological richness as ''normal", and they thus are blind to the historic change (Steen and Jachowski, 2013;Papworth et al., 2009). This may be especially true in urbanized areas where wetlands have been severely degraded. ...
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The aim of this study was to provide a baseline assessment of the turtle community in the coastal wetlands of the Greater Toronto Area. We documented turtle species diversity, abundance, reproductive classes, sex-ratios, and evidence of inter-wetland movement. Our study consisted of a series of mark-recapture surveys across eleven Lake Ontario coastal wetland complexes of the Greater Toronto Area performed between 2016 and 2019. We captured and marked 532 individual turtles of four native species (298 midland painted, Chrysemys picta marginata; 180 snapping, Chelydra serpentina; 7 Blanding's, Emydoidea blandingii, and 5 map, Graptemys geographica) and three non-native species (40 red-eared sli-der, Trachemys scripta elegans; 1 false map, Graptemys pseudogeographica, and 1 Chinese softshell, Pelodiscus sinensis). Of note was the capture of an exceptionally large male snapping turtle, one of the largest recorded in Canada for both length and mass. The age classes of both snapping and midland painted species presented large proportions of breeding-sized adults, yet midland painted turtles showed a potential low recruitment with an underrepresentation of non-reproductive females. The sex ratios of both midland painted and snapping turtles across the whole waterfront did not differ from the expected 1:1 ratio. We also recaptured 198 turtles (135 midland painted, 53 snapping, 6 Blanding's and 12 red-eared Sliders). The recaptured turtles revealed inter-wetland movements of 12 km over a two-year span for a midland painted turtle and an 8 km journey for a snapping turtle, potentially demonstrating some connectivity between geographically separate wetland complexes.
... Researchers studying the transmission of traditional knowledge have highlighted that scarce intergenerational communication largely affects knowledge transmission.Moreover, if compared to the elders' knowledge, younger generations might display substantially different perceptions on their environment, including, for example, a large unawareness of ecosystem change. This is largely because younger generations assess change relative to baselines that keep shifting through time, a phenomenon known as the Shifting Baseline Syndrome(Fernández- Llamazares et al. 2015;Steen and Jachowski 2013). Moreover, generational differences in ecological knowledge levels seem to be larger in industrialized societies, where the livelihood activities of younger generations are not nature-based and traditional knowledge is not necessarily needed for subsistence(Pilgrim et al. 2008). ...
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In the last decade, researchers have reported the erosion of Traditional Medicinal Plant Knowledge (TMPK), including declines in the knowledge about which plant species are medicines and in the practical skills for using these species. Among the various drivers explaining TMPK loss, the processes governing knowledge acquisition and transmission are not clearly understood. In this study we explore whether grandparent-grandchild proximity relates to child's knowledge, namely through oblique knowledge transmission. Based on the assumption that elders are a repository of TMPK, we hypothesized that children's physical and affective proximity to their grandparents might favor the transmission of TMPK and, therefore, be associated to higher child's TMPK. We test this hypothesis using data from children attending two schools in intermediate-rural towns Guadalix de la Sierra and Figueres, Spain. Contrary to our expectations, neither physical nor affective proximity to grandparents was significantly related to children's TMPK. We provide methodological (i.e., omitted variable bias) and theoretical (i.e., intergenerational knowledge transmission is weak or null in the study area) arguments that might explain our results. We conclude by highlighting the need to create initiatives for intergenerational dialogue that foster traditional knowledge transmission.
... Furthermore, Fischer et al. (2011) found that knowledge of previous population status was a significant factor in how people viewed current species' abundance, suggesting that knowledge and perception of past and present abundance are of importance. Lack of such knowledge, however, may lead to 'shifting baseline syndrome' (Pauly, 1995;Papworth et al., 2009;Steen and Jachowski, 2013) and a difference between how the public and conservation specialists view current species abundance and any changes. ...
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The relationship between nature and cultural ecosystem service (CES) benefits is well accepted but poorly understood, as is the potential role of biodiversity in the relationship. By means of a public questionnaire survey in Wiltshire, UK, the relationship between the presence of a range of common species groups, species group ‘charisma’, group abundance in the landscape, and the benefit that people felt that they derived from the species groups was investigated for a lowland multifunctional landscape.
... Even though the passage of information to successive generations is better facilitated in the 21st century by increased monitoring and enhanced access to information, information gaps persist (Rick and Lockwood 2013). Examples abound from both terrestrial and aquatic systems (Papworth et al. 2009), indicating that the degree to which humans have exploited species or facilitated population or range expansion of species may often be greater than revealed by the limited historical data (Steen and Jachowski 2013). ...
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This survey was first undertaken for the purpose of compiling a country-wide map of deer problem areas for use in classes. There is no such map. When the job was half done, it was mentioned t o a meeting of deer men at the 1946 Wildlife Conference. This group asked that the &dings be pub-lished. We were told that the findings, however crude, were needed in other states. Apparently deer men everywhere have found it hard t o convince the aver-age citizen, and especially the average deer hunter, that (1) delay in reduction of overpopulated deer ranges means ultimate shrinkage of both the herd and the range; (2) reduction is the only remedy, nothing else works; (3) t o ac-complish a reduction, female deer must be killed. Our hope is that this imperfect his-tory of the recent behavior of deer populations may convey the lesson that in managing overlarge herds, "too little and too late" is the worst possible policy. Our data are gathered from the litera-ture and by correspondence. We tried t o find in each state someone posted on local deer. He was asked t o map, clas-sify, and date the areas of deer trouble. The problem areas (black in Figure 1) are plotted upon a deer distribution map published by Gabrielson in 1943 (Hearings, House Committee on Wildlife, p. SO (Dec. 9-10)), but modified in many states by more recent local maps published in cited papers. We are indebted to our Correspond-ents for their patient cooperation in this enterprise. ERRORS Appraisal of this technical problem by mail has undoubtedly led to errors both in our map, and in the later sum-mary and classification of cases. One error inheres in individual dif-ferences among our correspondents in viewpoint, knowledge, and freedom to talk. In some states the official policy is t o minimize deer troubles, and in a few to deny their existence. Another error inheres in seasonal shifts of deer. In the west, where the shift is usually altitudinal, only winter range is ordinarily mapped as in trouble. In the east, winter shift is so local that winter yards cannot be mapped separately except on very local maps. Thus Wisconsin alone has over 500 known yards. The result is that in a map like Figure 1, a given degree of overstocking "shows more black" in eastern than in western states. In order not to obscure the black problem areas, Figure 1 is hatched on the vacapt or near-vacant range, i.e., deer ranges are white. Boundaries of these white areas are very crude, and omit much fine detail because detailed distribution maps do not exist. The net result is that Figure 1 shows much more white area than is actually inhabited by deer. Some problem spots (black) ap-pear on hatched (uninhabited) range. This is because the inhabited range is too small t o map, and is coextensive with the problem area.
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Raccoons (Procyon lotor) are considered synanthropic, with high densities reported from urban landscapes. However, little information is available on population density and demography within the urban matrix. To better understand how urban land-use patterns influence raccoon density and demographic patterns, we sampled raccoons at multiple, replicated sites across an urban landscape. Density differed by land-use type (F2,17 = 4.66, P = 0.027): urbanized sites, = 4.96 ± 2.64 raccoons/km2, range = 1.25–10.00 raccoons/km2; urban open sites, = 14.84 ± 6.35 raccoons/km2, range = 3.00–29.25 raccoons/km2; rural open sites, = 15.50 ± 4.66 raccoons/km2, range = 13.00–20.25. Although we found no clear patterns in sex ratio, reproductive condition, or body condition, we observed differences in age structure among urban open, rural open, and urbanized sites. The most striking difference was the absence of older animals at urbanized sites and relatively low numbers of young individuals at urban open sites. Raccoons were the dominant mesocarnivore in open fragments, but less so in the urban matrix. Spatial variation in density across urban landscapes is likely influenced by site level differences in abundance of anthropogenic resources and differences in habitat quality. Furthermore, the association between changes in land-use and population age structure may have reflected different mortality sources across the landscape. Our results illustrate that wildlife species considered synanthropic may have complex relationships with urban landscapes. © 2012 The Wildlife Society.
Article
Dominant species are thought to regulate species composition and assemblage structure. Invasion by a dominant species is thus likely to alter assemblages and anthropogenic disturbance often facilitates such invasions. In this study we examined the association of a dominant ant, Iridomyrmex purpureus, native to south-eastern Australia, with fire trails in national parks and its effects on ant assemblages. Association with fire trails was examined by comparing the numbers of I. purpureus nests on transects along fire trails with those in transects through surrounding vegetation. Ant assemblages and habitat characteristics of eight sandstone outcrops that supported colonies of I. purpureus were compared with those on eight that did not in summer and autumn 2000. We examined ant species richness, abundance, composition and biomass using quadrats, and resource use with Acacia botrycephalus seeds placed on rock and in vegetation. I. purpureus nests were considerably more common along fire trails than in surrounding vegetation. Sites with I. purpureus had similar species richness to those without, but a lower abundance and biomass of other ants and a different assemblage composition. These differences could not be attributed to any differences in measured habitat characteristics. Ecologically similar species, particularly other species of Iridomyrmex, were less abundant in areas with I. purpureus. While the biomass of other species was suppressed in areas with I. purpureus, the biomass of the dominant was several times that of the assemblage of other ants, a pattern shared with assemblages invaded by exotic species. In areas with I. purpureus, seeds were removed more rapidly from rock, but not vegetation, indicating that resources on rock may be under-exploited by other species. Regula- tion of invaded ant assemblages by this dominant ant is thus limited to functionally similar species, and this may be due to its use of resources that are unexploited in its absence.
Article
Brown-headed cowbird populations and their rate of brood parasitism on forest songbirds in eastern North America have increased since 1900. Brood parasitism of forest songbirds is highest near open habitat. High brood parasitism rates within isolated fragments of forest habitat reduce reproductive success of certain forest songbirds and may be responsible for their recent declines.
Article
Agriculture is the dominant land use in the Lower Flint River Basin (LFRB) of south-western Georgia, USA, and is often a significant disturbance factor affecting streams and riparian habitats. Streams in the LFRB harbor a great diversity of freshwater turtles, which are among the many groups of aquatic fauna impacted by agricultural disturbance to riparian habitats. The objective of this study was to assess turtle diversity and abundance in both agriculturally impacted and unimpacted or restored reaches of streams in the LFRB. In 2007 and 2008, we used hoop traps and effort-managed snorkel surveys to sample turtles on 14 reaches of two streams (Ichawaynochaway and Spring Creeks). We recorded 823 captures of 674 individuals representing nine turtle species. There was a measurable association between the percentage of riparian undisturbed land cover and the number of turtles captured for the four most frequently captured species (Trachemys scripta, Graptemys barbouri, Pseudemys concinna and Sternotherus minor). We found a negative relationship between the total number of turtles captured and percentage of undisturbed land cover within a 287 m buffer width due to a significant increase in the number of T. scripta in less-forested sections of the creeks; however, the number of G. barbouri captures declined with reduced undisturbed land cover. Species evenness was positively correlated with percentage of undisturbed land. These results suggest that loss of riparian forest is associated with a decline in freshwater diversity (evenness) and a decline in the abundance of the endemic, state protected G. barbouri; however, overall turtle abundance may remain stable or increase with loss of riparian forest cover due to an increase in common, cosmopolitan species. Our results suggest that maintenance or restoration of riparian forests is critical to freshwater turtle conservation.
Article
Aims Biogeographical evidence suggests a strong link between climate and patterns of species diversity, and climate change is known to cause range shifts. However, there is little understanding of how shifts affect community composition and we lack empirical evidence of recent impacts of climate change on the diversity of vertebrates. Using a long-term comprehensive dataset on bird abundance, we explore recent patterns of change in different components of species diversity and avian communities, and postulate a process to explain the observed changes in diversity and specialization.
Article
The extent of human-induced change and damage to Earth's ecosystems renders ecosystem repair an essential part of our future survival strategy, and this demands that restoration ecology provide effective conceptual and practical tools for this task. We argue that restoration ecology has to be an integral component of land management in today's world, and to be broadly applicable, has to have a clearly articulated conceptual basis. This needs to recognize that most ecosystems are dynamic and hence restoration goals cannot be based on static attributes. Setting clear and achievable goals is essential, and these should focus on the desired characteristics for the system in the future, rather than in relation to what these were in the past. Goal setting requires that there is a clear understanding of the restoration options available (and the relative costs of different options). The concept of restoration thresholds suggests that options are determined by the current state of the system in relation to biotic and abiotic thresholds. A further important task is the development of effective and easily measured success criteria. Many parameters could be considered for inclusion in restoration success criteria, but these are often ambiguous or hard to measure. Success criteria need to relate clearly back to specific restoration goals. If restoration ecology is to be successfully practiced as part of humanity's response to continued ecosystem change and degradation, restoration ecologists need to rise to the challenges of meshing science, practice and policy. Restoration ecology is likely to be one of the most important fields of the coming century.
Article
Local ecological knowledge can provide a unique source of data for conservation, especially in efforts to investigate the status of rare or possibly extinct species, but it is unlikely to remain constant over time. Loss of perspective about past ecological conditions caused by lack of communication between generations may create “shifting baseline syndrome,” in which younger generations are less aware of local species diversity or abundance in the recent past. This phenomenon has been widely discussed, but has rarely been examined quantitatively. We present new evidence of shifting baselines in local perception of regional species declines and on the duration of “community memory” of extinct species on the basis of extensive interviews with fishers in communities across the middle-lower Yangtze basin. Many Yangtze species have experienced major declines in recent decades, and the Yangtze River dolphin or baiji (Lipotes vexillifer) and Yangtze paddlefish (Psephurus gladius) may have become extinct during the 21st century. Although informants across all age classes were strongly aware of the Yangtze ecosystem's escalating resource depletion and environmental degradation, older informants were more likely to recognize declines in two commercially important fish species, Reeves’ shad (Tenualosa reevesii) and Yangtze pufferfish (Takifugu fasciatus), and to have encountered baiji and paddlefish in the past. Age was also a strong predictor of whether informants had even heard of baiji or paddlefish, with younger informants being substantially less likely to recognize either species. A marked decrease in local knowledge about the Yangtze freshwater megafauna matched the time of major population declines of these species from the 1970s onwards, and paddlefish were already unknown to over 70% of all informants below the age of 40 and to those who first started fishing after 1995. This rapid rate of cultural baseline shift suggests that once even megafaunal species cease to be encountered on a fairly regular basis, they are rapidly forgotten by local communities. Resumen: El conocimiento ecológico local puede proporcionar una fuente única de datos para la conservación, especialmente en esfuerzos para investigar el estatus de especies raras o posiblemente extintas, pero es poco probable que permanezca constante en el tiempo. La pérdida de perspectiva sobre las condiciones ecológicas pasadas causada por la falta de comunicación entre generaciones puede crear el “síndrome de directrices cambiantes,” con el que las generaciones jóvenes están menos enteradas de la diversidad o abundancia de especies local en el pasado reciente. Este fenómeno se ha discutido ampliamente, pero raras veces se ha examinado cuantitativamente. Presentamos nuevas evidencias de cambios en las directrices en la percepción local sobre la declinación de especies locales y sobre la duración de la “memoria de la comunidad” de especies extintas con base en entrevistas a pescadores en comunidades en la cuenca media-baja del Yangtze. Muchas especies del Yangtze han experimentado fuertes declinaciones en décadas recientes, y el delfín del Yangtze o baiji (Lipotes vexillifer) y el pez espátula del Yangtze (Psephurus gladius) pueden haberse extinguido durante el siglo veintiuno. Aunque los informantes en todas las clases de edades estaban muy conscientes de la reducción drástica de recursos y la degradación ambiental del ecosistema, los informantes de mayor edad tuvieron mejor conocimiento de las declinaciones de dos especies de peces de importancia comercial Tenualosa reevesii y Takifugu fasciatus, y reconocieron la presencia de baiji y pez espátula en el pasado, muy pocos informantes jóvenes reconocieron a ambas especies. La marcada disminución en el conocimiento ecológico local sobre la megafauna del Yangtze coincidió con el tiempo de las principales declinaciones poblacionales de estas especies a partir de 1970, y el pez espátula fue desconocido para más de 70% de los informantes menores a 40 años y para aquellos que comenzaron a pescar después de 1995. Esta rápida tasa de cambio de directrices culturales sugiere que una vez que se dejan de encontrar especies de megafauna en intervalos medianamente regulares, son olvidadas rápidamente por las comunidades locales.
Article
Historical abundances of many large marine vertebrates were tremendously greater than today. However, while pelagic sharks are known to have declined rapidly in the northwest Atlantic in recent years, there, as elsewhere, little is known about the former natural abundances of these species. Here, we compare initial (1950s) and recent (late-1990s) standardized catch rates of pelagic sharks in the Gulf of Mexico, the area where methods of exploitation between these two periods were most comparable. We estimate that oceanic whitetip and silky sharks, formerly the most commonly caught shark species, have declined by over 99 and 90%, respectively. That the former prevalence of oceanic whitetip sharks in this ecosystem is unrecognized today is clear evidence of shifting baselines. Our analysis provides the missing baseline for pelagic sharks in the Gulf of Mexico that is needed for the rational management and restoration of these species.
Article
Shifting baseline syndrome (SBS) is often referred to as a key issue for conservation, yet there is little evidence for its existence. The presence of SBS could influence the validity of participatory monitoring, local ecological knowledge, community based conservation, and conservation education. We outline two forms of SBS: (1) generational amnesia, where knowledge extinction occurs because younger generations are not aware of past biological conditions and (2) personal amnesia, where knowledge extinction occurs as individuals forget their own experience. Two conditions are essential to the identification of SBS: (1) biological change must be present in the system and (2) any perceived changes must be consistent with the biological data. If age or experience-related differences in perception are then found, generational amnesia may be occurring. Alternately, if individuals believe current conditions also occurred in the past, personal amnesia may be occurring. Previous studies have not fully addressed these conditions, and hence cannot provide indisputable evidence for the existence of SBS. We present three case studies to examine these issues, which demonstrate both forms of SBS. Shifting baseline syndrome is no longer a cautionary tale, but instead is a real problem for those using human perceptions of change to inform conservation policy-making or management.
Article
Human alteration of Earth is substantial and growing. Between one-third and one-half of the land surface has been transformed by human action; the carbon dioxide concentration in the atmosphere has increased by nearly 30 percent since the beginning of the Industrial Revolution; more atmospheric nitrogen is fixed by humanity than by all natural terrestrial sources combined; more than half of all accessible surface fresh water is put to use by humanity; and about one-quarter of the bird species on Earth have been driven to extinction. By these and other standards, it is clear that we live on a human-dominated planet.
Article
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Article
Large predators potentially can help shape the structure and functioning of terrestrial ecosystems, yet strong evidence of top-down herbivore limitation has not been widely reported in the scientific literature. Herein we synthesize outcomes of recent tri-trophic cascades studies involving the presence and absence of large predators for five national parks in the western United States, including Olympic, Yosemite, Yellowstone, Zion, and Wind Cave. Historical observations by park biologists regarding woody browse species and recently compiled age structure data for deciduous trees indicate major impacts to woody plant communities by ungulates following the extirpation or displacement of large predators. Declines in long-term tree recruitment indexed additional effects to plant communities and ecological processes, as well as shifts towards alternative ecosystem states. The magnitude and consistency of vegetation impacts found within these five parks, in conjunction with other recent North American studies, indicate that broad changes to ecosystem processes and the lower trophic level may have occurred in other parts of the western United States where large predators have been extirpated or displaced. Thus, where ungulates have significantly altered native plant communities in the absence of large predators, restoration of native flora is urgently needed to recover former ecosystem services. Following the reintroduction of previously extirpated gray wolves Canis lupus into Yellowstone National Park, a spatially patchy recovery of woody browse species (e.g., aspen Populus tremuloides, willow Salix spp., cottonwood Populus spp.) has begun, indicating that large predator recovery may represent an important restoration strategy for ecosystems degraded by wild ungulates.
Article
Large Carnivores and the Conservation of Biodiversity brings together more than thirty leading scientists and conservation practitioners to consider a key question in environmental conservation: Is the conservation of large carnivores in ecosystems that evolved with their presence equivalent to the conservation of biological diversity within those systems? Building their discussions from empirical, long-term data sets, contributors including James A. Estes, David S. Maehr, Tim McClanahan, Andr?s J. Novaro, John Terborgh, and Rosie Woodroffe explore a variety of issues surrounding the link between predation and biodiversity: What is the evidence for or against the link? Is it stronger in marine systems? What are the implications for conservation strategies? Large Carnivores and the Conservation of Biodiversity is the first detailed, broad-scale examination of the empirical evidence regarding the role of large carnivores in biodiversity conservation in both marine and terrestrial ecosystems. It contributes to a much more precise and global understanding of when, where, and whether protecting and restoring top predators will directly contribute to the conservation of biodiversity. Everyone concerned with ecology, biodiversity, or large carnivores will find this volume a unique and thought-provoking analysis and synthesis.
Ecological impacts of deer overabundance
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Biological invasions, resilience and restoration. Pages 265-280 in
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Past imperfect: using historical ecology and baseline data for conservation and restoration projects in North America
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