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Abstract

Fluxes of matter, energy, and information over space and time contribute to ecosystems’ functioning. The meta-ecosystem framework addresses the dynamics of ecosystems linked by these fluxes, however, to date, meta-ecosystem research focused solely on fluxes of energy and matter, neglecting information. This is problematic due to organisms’ varied responses to information, which influence local ecosystem dynamics and can alter spatial flows of energy and matter. Furthermore, information itself can move between ecosystems. Therefore, information should contribute to meta-ecosystem dynamics, such as stability and productivity. Specific subdisciplines of ecology currently consider different types of information (e.g., social and cultural information, natural and artificial light or sound, body condition, genotype, and phenotype). Yet neither the spatiotemporal distribution of information nor its perception are currently accounted for in general ecological theories. Here, we provide a roadmap to synthesize information and meta-ecosystem ecology. We begin by defining information in a meta-ecological context. We then review and identify challenges to be addressed in developing information meta-ecology. Finally, we present new hypotheses for how information could impact dynamics across scales of spatio-temporal and biological organization.

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Animal movements are important drivers of nutrient redistribution that can affect primary productivity and biodiversity across various spatial scales. Recent work indicates that incorporating these movements into ecosystem models can enhance our ability to predict the spatio-temporal distribution of nutrients. However, the role of animal behaviour in animal-mediated nutrient transport (i.e. active subsidies) remains under-explored. Here we review the current literature on active subsidies to show how the behaviour of active subsidy agents makes them both ecologically important and qualitatively distinct from abiotic processes (i.e. passive subsidies). We first propose that animal movement patterns can create similar ecological effects (i.e. press and pulse disturbances) in recipient ecosystems, which can be equal in magnitude to or greater than those of passive subsidies. We then highlight three key behavioural features distinguishing active subsidies. First, organisms can transport nutrients counter-directionally to abiotic forces and potential energy gradients (e.g. upstream). Second, unlike passive subsidies, organisms respond to the patterns of nutrients that they generate. Third, animal agents interact with each other. The latter two features can form positive-or negative-feedback loops, creating patterns in space or time that can reinforce nutrient hotspots in places of mass aggregations and/or create lasting impacts within ecosystems. Because human-driven changes can affect both the space-use of active subsidy species and their composition at both population (i.e. individual variation) and community levels (i.e. species interactions), predicting patterns in nutrient flows under future modified environmental conditions depends on understanding the behavioural mechanisms that underlie active subsidies and variation among agents' contributions. We conclude by advocating for the integration of animal behaviour, animal movement data, and individual variation into future conservation efforts in order to provide more accurate and realistic assessments of changing ecosystem function.
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Ecologists often assume that range expansion will be fastest in landscapes composed entirely of the highest‐quality habitat. Theoretical models, however, show that range expansion depends on both habitat quality and habitat‐specific movement rates. Using data from 78 species in 70 studies, we find that animals typically have faster movement through lower‐quality environments (73% of published cases). Therefore, if we want to manage landscapes for range expansion, there is a trade‐off between promoting movement with nonhostile matrix, and promoting population growth with high‐quality habitat. We illustrate how this trade‐off plays out with the use of an exemplar species, the Baltimore checkerspot butterfly. For this species, we calculate that the expected rate of range expansion is fastest in landscapes with ~15% high‐quality habitat. Behavioral responses to nonhabitat matrix have often been documented in animal populations, but rarely included in empirical predictions of range expansion. Considering movement behavior could change land‐planning priorities from focus on high‐quality habitat only to integrating high‐ and low‐quality land cover types, and evaluating the costs and benefits of different matrix land covers for range expansion.
Article
Animals experience varying levels of predation risk as they navigate heterogeneous landscapes, and behavioral responses to perceived risk can structure ecosystems. The concept of the landscape of fear has recently become central to describing this spatial variation in risk, perception, and response. We present a framework linking the landscape of fear, defined as spatial variation in prey perception of risk, to the underlying physical landscape and predation risk, and to resulting patterns of prey distribution and antipredator behavior. By disambiguating the mechanisms through which prey perceive risk and incorporate fear into decision making, we can better quantify the nonlinear relationship between risk and response and evaluate the relative importance of the landscape of fear across taxa and ecosystems.
Article
Artificial lighting at night (ALAN) is a global phenomenon that can be detrimental to organisms at individual and population levels, yet potential consequences for communities and ecosystem functions are less resolved. Riparian systems may be particularly vulnerable to ALAN. We investigated the impacts of ALAN on invertebrate community composition and food web characteristics for linked aquatic‐terrestrial ecosystems. We focused on food chain length (FCL), a central property of ecological communities that can influence their structure, function, and stability; and the contribution of aquatically derived energy (i.e., nutritional subsidies originating from stream periphyton). We collected terrestrial arthropods and emergent aquatic insects from a suite of stream and wetland sites in Columbus, Ohio, USA. Stable isotopes of carbon (13C) and nitrogen (15N) were used to infer FCL and contribution of aquatically derived energy. We found that moderate‐to‐high levels of ALAN altered invertebrate community composition, favoring primarily predators and detritivores. Impacts of ALAN, however, were very taxon specific as illustrated, for example, by the negative impact of ALAN on the abundance of orb‐web spiders belonging to the families Tetragnathidae and Araneidae: key invertebrate riparian predators. Most notably, we observed decreases in both invertebrate FCL and reliance on aquatically derived energy under ALAN (although aquatic energetic contributions appeared to increase again at higher levels of ALAN), in addition to shifts in the timing of reciprocal nutritional subsidies. Our study demonstrates that ALAN can alter the flows of energy between aquatic and terrestrial systems, thereby representing an environmental perturbation that can cross ecosystem boundaries. Given projections for global increases in ALAN, both in terms of coverage and intensity, these results have broad implications for stream ecosystem structure and function.
Article
Closure from the earth's atmosphere is a critical test of an ecosystem's ability to function. In our earlier testing of autotrophic Closed Ecological Systems (CESs), a C:N ratio of 26.4 (3.3 mM NaHCO3 and 0.125 mM NaNO3) supported algal and Daphnia populations for months, but developed extreme pH values (∼11 ungrazed, >10, grazed), suggesting that the systems were carbon-limited. Only approximately half the HCO3⁻ (bicarbonate) would be expected to be available to green algae, the other portion becoming CO3⁻² (carbonate). In an experiment described here, CESs were developed to explore a greater range of C:N ratios. To keep the medium from becoming too osmotically concentrated, NaNO3 was reduced to 0.0312 mM and NaHCO3 tested at 3.3, 13.2, and 26.4 mM, resulting in nominal C:N ratios of 105, 422, and 845. However, additional carbon was not beneficial to long-term survival of the organisms. The algal abundance was relatively insensitive to C:N ratio; greater concentrations of C were not beneficial. Daphnia populations were sensitive to C:N ratio and persisted longer at the lowest C:N ratio of 105. All of the C:N ratios tested in these CESs are outside of the expected range suggested from ecological studies, which is based on the Redfield Ratio of 6.625 C:N, the expected chemical composition of algae. Two potential explanations for the apparent high C demand in our CESs are suggested by the literature. The first is production of fatty algal cells, e.g., one of the algal species, Scenedesmus obliquus, is reported to produce high-lipid cells that could have a higher C:N ratio than the Redfield Ratio. The second is “carbon overconsumption,” which has been suggested for N-limited marine phytoplankton communities dominated by diatoms or nutrient deficient algal communities dominated by small cells that are under-represented by chlorophyll a measurements. The unexpected C dynamics found in our CES tests could be relevant to the design of biological life support systems that must be provisioned with adequate elements for long-term ecosystem functionality. If the actual demand for C is underestimated, its storage may be inadequate.
Article
The transport of resource subsidies by animals has been documented across a range of species and ecosystems. Although many of these studies have shown that animal resource subsidies can have significant effects on nutrient cycling, ecosystem productivity, and food‐web structure, there is a great deal of variability in the occurrence and strength of these effects. Here we propose a conceptual framework for understanding the context dependency of animal resource subsidies, and for developing and testing predictions about the effects of animal subsidies over space and time. We propose a general framework, in which abiotic characteristics and animal vector characteristics from the donor ecosystem interact to determine the quantity, quality, timing, and duration (QQTD) of an animal input. The animal input is translated through the lens of recipient ecosystem characteristics, which include both abiotic and consumer characteristics, to yield the QQTD of the subsidy. The translated subsidy influences recipient ecosystem dynamics through effects on both trophic structure and ecosystem function, which may both influence the recipient ecosystem's response to further inputs and feed back to influence the donor ecosystem. We present a review of research on animal resource subsidies across ecosystem boundaries, placed within the context of this framework, and we discuss how the QQTD of resource subsidies can influence trophic structure and ecosystem function in recipient ecosystems. We explore the importance of understanding context dependency of animal resource subsidies in increasingly altered ecosystems, in which the characteristics of both animal vectors and donor and recipient ecosystems may be changing rapidly. Finally, we make recommendations for future research on animal resource subsidies, and resource subsidies in general, that will increase our understanding and predictive capacity about their ecosystem effects.
Article
Ungulate migrations are assumed to stem from learning and cultural transmission of information regarding seasonal distribution of forage, but this hypothesis has not been tested empirically. We compared the migratory propensities of bighorn sheep and moose translocated into novel habitats with those of historical populations that had persisted for hundreds of years. Whereas individuals from historical populations were largely migratory, translocated individuals initially were not. After multiple decades, however, translocated populations gained knowledge about surfing green waves of forage (tracking plant phenology) and increased their propensity to migrate. Our findings indicate that learning and cultural transmission are the primary mechanisms by which ungulate migrations evolve. Loss of migration will therefore expunge generations of knowledge about the locations of high-quality forage and likely suppress population abundance.
Article
This review of metapopulation biology has a special focus on Professor Ilkka Hanski's (1953-2016) research. Hanski made seminal contributions to both empirical and theoretical metapopulation biology throughout his scientific career. Hanski's early research focused on ecological aspects of metapopulation biology, in particular how the spatial structure of a landscape influences extinction thresholds and how habitat loss and fragmentation can result in extinction debt. Hanski then used the Glanville fritillary system as a natural laboratory within which he studied genetic and evolutionary processes, such as the influence of inbreeding on extinction risk and variation in selection for dispersal traits generated by landscape variation. During the last years of his career, Hanski's work was in the forefront of the rapidly developing field of eco-evolutionary dynamics. Hanski was a pioneer in showing how molecular-level underpinnings of trait variation can explain why evolutionary change can occur rapidly in natural populations and how these changes can subsequently influence ecological dynamics.
Article
When individual animals make decisions, they routinely use information produced intentionally or unintentionally by other individuals. Despite its prevalence and established fitness consequences, the effects of such social information on ecological dynamics remain poorly understood. Here, we synthesize results from ecology, evolutionary biology, and animal behavior to show how the use of social information can profoundly influence the dynamics of populations and communities. We combine recent theoretical and empirical results and introduce simple population models to illustrate how social information use can drive positive density-dependent growth of populations and communities (Allee effects). Furthermore, social information can shift the nature and strength of species interactions, change the outcome of competition, and potentially increase extinction risk in harvested populations and communities.
Article
Relating biodiversity to ecosystem functioning in natural communities has become a paramount challenge as links between trophic complexity and multiple ecosystem functions become increasingly apparent. Yet, there is still no generalised approach to address such complexity in biodiversity-ecosystem functioning (BEF) studies. Energy flux dynamics in ecological networks provide the theoretical underpinning of multitrophic BEF relationships. Accordingly, we propose the quantification of energy fluxes in food webs as a powerful, universal tool for understanding ecosystem functioning in multitrophic systems spanning different ecological scales. Although the concept of energy flux in food webs is not novel, its application to BEF research remains virtually untapped, providing a framework to foster new discoveries into the determinants of ecosystem functioning in complex systems.
Article
The environmental impacts of artificial light at night have been a rapidly growing field of global change science in recent years. Yet, light pollution has not achieved parity with other global change phenomena in the level of concern and interest it receives from the scientific community, government and nongovernmental organizations. This is despite the globally widespread, expanding and changing nature of night-time lighting and the immediacy, severity and phylogenetic breath of its impacts. In this opinion piece, we evidence 10 reasons why artificial light at night should be a focus for global change research in the 21st century. Our reasons extend beyond those concerned principally with the environment, to also include impacts on human health, culture and biodiversity conservation more generally. We conclude that the growing use of night-time lighting will continue to raise numerous ecological, human health and cultural issues, but that opportunities exist to mitigate its impacts by combining novel technologies with sound scientific evidence. The potential gains from appropriate management extend far beyond those for the environment, indeed it may play a key role in transitioning towards a more sustainable society.
Article
The meta-ecosystem framework demonstrates the significance of among-ecosystem spatial flows for ecosystem dynamics and has fostered a rich body of theory. The high level of abstraction of the models, however, impedes applications to empirical systems. We argue that further understanding of spatial dynamics in natural systems strongly depends on dense exchanges between field and theory. From empiricists, more and specific quantifications of spatial flows are needed, defined by the major categories of organismal movement (dispersal, foraging, life-cycle, and migration). In parallel, the theoretical framework must account for the distinct spatial scales at which these naturally common spatial flows occur. Integrating all levels of spatial connections among landscape elements will upgrade and unify landscape and meta-ecosystem ecology into a single framework for spatial ecology.
Article
Ambiguous empirical support for ‘landscapes of fear’ in natural systems may stem from failure to consider dynamic temporal changes in predation risk. The lunar cycle dramatically alters night-time visibility, with low luminosity increasing hunting success of African lions. We used camera-trap data from Serengeti National Park to examine nocturnal anti-predator behaviours of four herbivore species. Interactions between predictable fluctuations in night-time luminosity and the underlying risk-resource landscape shaped herbivore distribution, herding propensity and the incidence of ‘relaxed’ behaviours. Buffalo responded least to temporal risk cues and minimised risk primarily through spatial redistribution. Gazelle and zebra made decisions based on current light levels and lunar phase, and wildebeest responded to lunar phase alone. These three species avoided areas where likelihood of encountering lions was high and changed their behaviours in risky areas to minimise predation threat. These patterns support the hypothesis that fear landscapes vary heterogeneously in both space and time.
Article
1.Connections between ecosystems via animals (active subsidies) support ecosystem services and contribute to numerous ecological effects. Thus, the ability to predict the spatial distribution of active subsidies would be useful for ecology and conservation. 2.Previous work modeling active subsidies focused on implicit space or static distributions, which treat passive and active subsidies similarly. Active subsidies are fundamentally different from passive subsidies, because animals can respond to the process of subsidy deposition and ecosystem changes caused by subsidy deposition. 3.We propose addressing this disparity by integrating animal movement and ecosystem ecology to advance active subsidy investigations, make more accurate predictions of subsidy spatial distributions, and enable a mechanistic understanding of subsidy spatial distributions. 4.We review selected quantitative techniques that could be used to accomplish integration and lead to novel insights. The ultimate objective for these types of studies is predictions of subsidy spatial distributions from characteristics of the subsidy and the movement strategy employed by animals that transport subsidies. These advances will be critical in informing the management of ecosystem services, species conservation, and ecosystem degradation related to active subsidies. This article is protected by copyright. All rights reserved.
Article
Community ecology was traditionally an integrative science devoted to studying interactions between species and their abiotic environments in order to predict species' geographic distributions and abundances. Yet for philosophical and methodological reasons it has become divided into two enterprises: one devoted to local experimentation on species interactions to predict community dynamics; the other devoted to statistical analyses of abiotic and biotic information to describe geographic distribution. Our goal here is to instigate thinking about ways to reconnect the two enterprises and thereby return to a tradition to do integrative science. We focus specifically on the community ecology of predators and prey, which is ripe for integration. This is because there is active, simultaneous interest in experimentally resolving the nature and strength of predator-prey interactions as well as explaining pattern across landscapes and seascapes. We begin by describing a conceptual theory rooted in classical analyses of non-spatial food web modules used to predict species interactions. We show how such modules can be extended to consideration of spatial context using the concept of habitat domain. Habitat domain describes the spatial extent of habitat space that predators and prey use while foraging, which differs from home range, the spatial extent used by an animal to meet all of its daily needs. This conceptual theory can be used to predict how different spatial relations of predators and prey could lead to different emergent multiple predator-prey interactions such as whether predator consumptive or non-consumptive effects should dominate, and whether intraguild predation, predator interference or predator complementarity are expected. We then review the literature on studies of large predator-prey interactions that make conclusions about the nature of multiple predator-prey interactions. This analysis reveals that while many studies provide sufficient information about predator or prey spatial locations, and thus meet necessary conditions of the habitat domain conceptual theory for drawing conclusions about the nature of the predator-prey interactions, several studies do not. We therefore elaborate how modern technology and statistical approaches for animal movement analysis could be used to test the conceptual theory, using experimental or quasi-experimental analyses at landscape scales. This article is protected by copyright. All rights reserved.
Article
Anthropogenic noise threatens ecological systems, including the cultural and biodiversity resources in protected areas. Using continental-scale sound models, we found that anthropogenic noise doubled background sound levels in 63% of U.S. protected area units and caused a 10-fold or greater increase in 21%, surpassing levels known to interfere with human visitor experience and disrupt wildlife behavior, fitness, and community composition. Elevated noise was also found in critical habitats of endangered species, with 14% experiencing a 10-fold increase in sound levels. However, protected areas with more stringent regulations had less anthropogenic noise. Our analysis indicates that noise pollution in protected areas is closely linked with transportation, development, and extractive land use, providing insight into where mitigation efforts can be most effective. © 2017, American Association for the Advancement of Science. All rights reserved.
Article
Human settlements and transport networks are growing rapidly worldwide. Since the early 20th Century their expansion has been accompanied by increasing illumination of the environment at night, a trend that is likely to continue over the decades to come. Consequently, a growing proportion of the world's ecosystems are exposed to artificial light at night, profoundly altering natural cycles of light and darkness. While in recent years there have been advances in our understanding of the effects of artificial light at night on the behaviour and physiology of animals in the wild, much less is known about the impacts on wild plants and natural or semi-natural vegetation composition. This is surprising, as effects of low-intensity light at night on flowering, phenology and growth form are well known in laboratory and greenhouse studies. 2.In a long-term experimental field study we exposed a semi-natural grassland to artificial light at intensities and wavelengths typical of those experienced by roadside vegetation under street lighting. 3.We found that lighting affected the trajectory of vegetation change, leading to significant differences in biomass and plant cover in the dominant species. 4.Changes in flowering phenology were variable between years, with grass species flowering between 4 days earlier and 12 days later under artificial light. 5.Policy implications. Our results demonstrate that artificial light, at levels equivalent to those in street-lit environments, can affect species composition in semi-natural vegetation. This highlights the importance of considering artificial light as a driver of vegetation change in urban, suburban and semi-natural ecosystems, and where possible of minimising or excluding artificial light from habitats of conservation importance. This article is protected by copyright. All rights reserved.
Article
Chronic anthropogenic underwater noise, such as vessel noise, is now recognized as a world-wide problem. Marine noise from vessels, ranging from super tankers to small motorboats is increasingly recognized as being both a persistent and pervasive pollutant. Furthermore, due to its spatial and temporal variability, vessel noise pollution represents a particular challenge for marine conservation, management, and planning. This paper presents the outputs of a horizon scanning exercise that brought together a group of 40 individuals from across Canada, including: researchers, policy makers, NGOs and other end-users who work in the field of marine acoustics. The goal was to identify priority information needs, related to marine vessel acoustics, to inform new research and address policy needs. Via an iterative Delphi style process, participants identified 10 priority research questions related to marine vessel acoustic science; for example, How important is it to identify and maintain acoustic refugia? What attributes of marine vessels are the most effective indicators of marine noise? The questions were then further considered in terms of extent of current knowledge, time scale by which they can be achieved, the financial resources required and the importance of answering the question. Subsequently, the authors conducted a search of the peer-reviewed literature to situate the challenges highlighted by the horizon scanning exercise within the broader global research. Results show that investigating the attributes of marine vessels that are the most effective indicators of marine noise is a viable research question to tackle first. In addition, underpinning many of these questions is the need of long-term data collection and monitoring of both vessel traffic and marine mammal populations.