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Many seabirds congregate in large colonies for breeding, a time when they are central place foragers. An influential idea in seabird ecology posits that competition during breeding results in an area of reduced prey availability around colonies, a phenomenon known as Ashmole's halo, and that this limits colony size. This idea has gained empirical support, including the finding that species coexisting within a colony might be able to do so by foraging on a single prey species but at different distances. Here, we provide a comprehensive mathematical model for central place foragers exploiting a single prey in a two-dimensional environment, where the prey distribution is the result of intrinsic birth and death, movement in space, and mortality due to foraging birds (we also consider a variant tailored toward colonial social insects). Bird predation at different distances occurs according to an ideal free foraging distribution that maximizes prey delivery under flight and search costs. We fully characterize the birds' ideal free distribution and the prey distribution it generates. Our results show that prey depletion halos around breeding colonies are a robust phenomenon and that the birds' ideal free distribution is sensitive to prey movement. Furthermore, coexistence of several seabird species on a single prey easily emerges through behavioral niche partitioning whenever trait differences between species entail trade-offs between efficiently exploiting a scarce prey close to the colony and a more abundant prey far away. Such behavioral-based coexistence-inducing mechanism should generalize to other habitat and diet choice scenarios. [ABSTRACT FROM AUTHOR]

The ideal free distribution (IFD) theory predicts that individuals are free to move among habitat patches and distribute among them "ideally," in order to maximize individual evolutionary fitness. Size and quality of habitat patches then should directly impact the number of individuals occupying them, and connectivity of habitat patches likely plays a role if dispersal is limited. However, habitat patches can be distributed so that movement no longer can be considered free, for example, when patches are isolated. Challenges stemming from patch delimitation and detection rate of occupants further complicate efforts attempting to resolve such patterns. Here, we utilize as habitat patches the orb webs of four different populations belonging to three golden orb weaver spider species, Nephila pilipes (Fabricius, 1793), Nephilingis livida (Vinson, 1863), and Trichonephila clavipes (Linnaeus, 1767), and the obligate spider kleptoparasites (Argyrodinae, Theridiidae) that are associated with their webs. We examine how the IFD predicts the abundance of kleptoparasites under different patterns of patch size and distribution. We found that larger host webs, that is, habitat patches that contain more resources, are occupied by a higher number of kleptoparasitic spiders, regardless of their degree of isolation. Although the free movement prediction is often violated in natural systems, we find no evidence for habitat patch connectivity affecting the abundance of kleptoparasites, indicating that their dispersal ability facilitates the location and colonization of habitat patches regardless of their isolation. Therefore, our results support the interaction between argyrodine kleptoparasitic spiders and the webs of golden orb weavers to be a suitable natural system for studying the IFD. [ABSTRACT FROM AUTHOR]

Temporal synchronization is a relatively common ecological phenomenon in population dynamics. Examples range from annual and biennial plants to Salmon to Cicadas. In discrete-time matrix population models, competition between stages may result in synchronous cycles in which stages are temporally separated. Our work shows how spatial density-dependency dynamics can have a crucial role in population stability through synchronization in a migratory population. Migration is a diverse phenomenon and can be categorized into many forms. The most common type of migration is partial migration, in which some individuals migrate between habitats and others remain in a single habitat during their entire life. We use a discrete stage structure matrix model to investigate which density dependence mechanisms would cause a stable cyclic behavior with alternating and separated generations of juveniles, migrant, and non-migrant adults. We also studied the subsequent adaptive dynamics, which require investigating whether a mutant can invade the dynamic 2-cycle. We also found a dynamic dichotomy between the oscillating 2-cycles and positive equilibria for the partially migrating populations. Using adaptive dynamics and center manifold theory, we showed the existence of an evolutionary stable strategy. We examined how the ideal free distribution (IFD) arises in the context of a temporally separated population. We also show that the ideal free distributions for synchronous 2-cycles are evolutionary stable strategies if migrants and non-migrants experience density-dependent competition with juveniles during reproduction. [ABSTRACT FROM AUTHOR]

Indoor spaces are essential to most humans' lives. Furthermore, in many cases, buildings are shared indoor environments that contain diverse people and resources. Spatial patterns of use are important but under‐examined aspects of human‐building interactions. This study leverages perspectives from human‐environment geography and mechanical engineering to examine spatial patterns of use within a network of shared indoor spaces in an academic building at a research university in the United States. Here we ask: (1) What spaces and resources do building users value? and (2) How are values associated with observed measures of use? We hypothesise that spatial patterns of use follow an ideal free distribution (IFD), a common ecological model of resource use. To test this, we define measures of value and use derived from mixed qualitative (n = 50) and survey‐based social data (n = 196) and data from a building‐based system of accelerometers. Our analyses provide some support for the IFD hypothesis. We discuss the implications of this finding and potential new avenues for geographic research in shared indoor environments. [ABSTRACT FROM AUTHOR]

An Allee effect is a density-dependent phenomenon in which population growth or individual components of fitness increase as population density increases. Understanding the density-dependent effects is vital to elucidate how populations evolve and to investigate evolutionary stability. Partial migration, where a proportion of a population migrates while other individuals remain resident, is widespread across most migratory lineages. However, the mechanism still needs to be better understood in most taxa, especially those experiencing positive density-dependent effects. Here we investigate the evolutionary stability of a partial migration population with only the migrant population experiencing Allee effects. Using the Evolutionary Game Theoretic (EGT) approach, we prove the existence and uniqueness of an evolutionary stable strategy (ESS). EGT provides a mathematical framework for understanding and modelling Darwinian evolution by natural selection. We also show that the ESS is the only Ideal Free Distribution (IFD) that arises in the context of a partially migrating population in a two-habitat environment. [ABSTRACT FROM AUTHOR]

In this paper, we develop an integrodifference equation model that incorporates spatial memory and learning so that each year, a fraction of the population use the same dispersal kernel as the previous year, and the remaining individuals return to where they bred or were born. In temporally static environments, the equilibrium of the system corresponds to an ideal free dispersal strategy, which is evolutionarily stable. We prove local stability of this equilibrium in a special case, and we observe convergence towards this equilibrium in numerical computations. When there are periodic or stochastic temporal changes in the environment, the population is less able to match the environment, but is able to do so to some extent depending on the parameters. Overall, the mechanism proposed in this model shows a possible way for the dispersal kernel of a population to evolve towards an ideal free dispersal kernel. [ABSTRACT FROM AUTHOR]

The Fremont provide an important case study to examine the resilience of ancient farmers to climatic downturns, because they lived at the far northern margin of intensive maize agriculture in the American West, where the constraints on maize production are made abundantly clear. Using a tree-ring and simulation-based reconstruction of average annual precipitation and maize growing degree days, along with cost-distance to perennial streams, we model spatial variability in Fremont site density in the eastern Great Basin. The results of our analysis have implications for defining the ecological envelope in which farming is a viable strategy across this arid region and can be used to predict where and why maize farming strategies might evolve and eventually collapse as climate changes over time. [ABSTRACT FROM AUTHOR]

Interspecific interactions, including predator–prey, intraguild predation (IGP) and competition, may drive distribution and habitat use of predator communities. However, elucidating the relative importance of these interactions in shaping predator distributions is challenging, especially in marine communities comprising highly mobile species.We used individual‐based models (IBMs) to predict the habitat distributions of apex predators, intraguild (IG) prey and prey. We then used passive acoustic telemetry to test these predictions in a subtropical marine predator community consisting of eight elasmobranch (i.e. shark and ray) species in Bimini, The Bahamas.IBMs predicted that prey and IG prey will preferentially select habitats based on safety over resources (food), with stronger selection for safe habitat by smaller prey. Elasmobranch space‐use patterns matched these predictions. Species with predator–prey and asymmetrical IGP (between apex and small mesopredators) interactions showed the clearest spatial separation, followed by asymmetrical IGP among apex and large mesopredators. Competitors showed greater spatial overlap although with finer‐scale differences in microhabitat use.Our study suggests space‐use patterns in elasmobranchs are at least partially driven by interspecific interactions, with stronger spatial separation occurring where interactions include predator–prey relationships or IGP. [ABSTRACT FROM AUTHOR]

Between 2100 and 500 BP, maize farming spread throughout the American Southwest, driving changes in land use patterns and relative increases in the number of archaeological sites, which is commonly interpreted as increases in population. In the context of the Southwest, with its variable topography and limited water sources, the locations suitable for productive maize agriculture are limited. Higher elevation locations often have a greater abundance of water, both in the form of precipitation and perennial water sources but lack the growing season lengths required for maize farming. Lower elevation locations have the long growing seasons required for maize, but often have higher evaporation rates corresponding with higher temperatures, and thus decreased soil moisture retention. The relationship between elevation and maize agriculture is well recognized, and locations where both growing season length and moisture requirements can be met serve as a Goldilocks Zone in which maize farming is possible. Here, we use a regional approach to model the Goldilocks Zone for maize farming in Utah, and then contextualize patterns of settlement and abandonment on the West Tavaputs Plateau (WTP) in east-central Utah. We use archaeological sites with direct evidence of maize cultivation, modern growing degree days estimates, and modern estimates of moisture abundance to bracket the prehistoric maize farming niche in Utah. Then, we apply the model to archaeological data from the WTP to test hypotheses derived from the Ideal Free Distribution model about the effects population and precipitation changes had on prehistoric land use patterns of settlement and abandonment, and whether the patterns of settlement and abandonment differ from one another. We find that a) population drives land use patterns in the WTP, but not in the way we originally hypothesized, suggesting there is an important decision variable missing from our model, which may pertain to the specific topographic setting of the WTP and the distribution of its water sources, b) precipitation has no effect on land use patterns suggesting that maize agriculture on the WTP was dependent on irrigation, and c) that patterns of settlement and abandonment seem to mirror each other. [ABSTRACT FROM AUTHOR]

We used isodars, developed from the ideal free distribution (IFD), to predict the distribution of fishing effort across regulatory boundaries in the south-western Scotian Shelf’s haddock fishery. Our analysis was focused around the boundary between Northwest Atlantic Fisheries Organization’s Divisions 4X and 5Z. While effort within 4X was related to the standardized catch value and effort experienced along the 4X–5Z boundary, most effort predictions across the boundary were also accurate. Accuracy of these cross-boundary isodars suggests that a high degree of movement across the boundary meets the IFD assumption of free movement and thus, effort on one side of the boundary is related to fishing success on the other side of the boundary. Fisheries management strategies should adopt a broad view that encompasses adjacent regulatory regions to understand where vessels may choose to fish when multiple regulatory regions are accessible. In fisheries where isodars describe effort distributions across a regulatory boundary, the relative abundance of the underlying fish population could be better indicated by effort distribution among regulatory regions than by catch rates.

Ecological models are used to understand where fishing vessels operate, improving fisheries management success. The ideal free distribution (IFD) predicts equalization of catch across locations in response to distributions of fish and competing vessels. We applied the IFD as a null model to investigate the movement and catch per vessel (CPUE) of the sockeye salmon drift gillnet fleet in Bristol Bay, AK, from 1980 to 2019. The IFD prediction of equal CPUE across areas was not supported, so we explored violations of two assumptions of the theory. We categorized each vessel according to its mobility, highlighting the "free to move" assumption, and found that when we removed nonmobile vessels, some districts had fewer vessels than predicted from their high CPUE. We examined the "equal competitive ability" assumption by calculating the average CPUE, relative to success of other vessels. The underutilization of profitable districts persisted. Overall, the fleet underused high CPUE areas when considering differences in mobility and relative fishing success, indicating that unmeasured safety concerns, travel costs, knowledge of fishing grounds, or other factors could be preventing an IFD. [ABSTRACT FROM AUTHOR]

The concept of maximum sustainable yield (MSY), and the underlying Schaefer model, remain relevant in fisheries management today in spite of past difficulties. However, this model is often applied without the consideration of the spatial structure or dynamics of fishing activities. We expand the Schaefer model to account for multiple fishing sites and fishing activities (effort) that follow an ideal free distribution (IFD, a form of Nash equilibrium) driven by exploitation. We explore this conceptual model using both analytical and numerical solutions. MSY across the fishery is unaffected by the spatial structure when fishing is allocated independently within sites. However, in other cases IFD effort dynamics depress MSY and modify the values of associated reference points. The game theoretic aspect of fleet dynamics should be considered in the use of MSY as a management reference point or during the application of the Schaefer model to data‐limited fisheries. Recommendations for Resource Managers: Fisheries where fishing activities move among spatially distinct stocks should be examined for the presence of ideal free effort dynamics.When fishing activities follow an ideal free distribution the maximum sustainable yield (MSY reference point may be less than that estimated without considering effort dynamics, but this depends upon the spatial scale of both effort and fish dynamics.Fishery models used to provide quantitative estimates of MSY should consider spatial effort dynamics when there is empirical evidence for equalization of profitability among sites fished (IFD dynamics). [ABSTRACT FROM AUTHOR]

Variations in habitat quality in space and time prompt birds to track these changes to optimise their fitness. We investigated movements of Greater Flamingos Phoenicopterus roseus between long-established North Mediterranean breeding colonies and a new, fairly unpredictable, intermittently suitable South Mediterranean breeding colony (Ezzemoul, Algeria). Among the flamingos observed as breeders at Ezzemoul in 2006 and 2009, 59 and 26 ringed individuals, respectively, were observed earlier during the same breeding season at another North Mediterranean colony, thus providing the first evidence of a within-season large scale displacement (> 1000km) from one colony to another. We suggest that breeding failure and a much higher nest density at the northern long-established colonies triggered these movements. Breeding success and body condition of chicks at Ezzemoul compared favourably with those at Fuente de Piedra (Spain) indicating that on a large spatial scale and on a longer time frame, density-dependent breeding success across Greater Flamingo colonies may induce a shift from an Ideal Despotic Distribution to an Ideal Free Distribution. —Boucheker, A., Nedjah, R., Boulkhssaïm, M., Germain, Ch., Garrido, A., Rendón, M.A., Amat, J.A., Rendón-Martos, M., Prodon, R., Béchet, A. & Samraoui, B. (2024). Tracking changes and shifting homes: Within-season displacement of Greater Flamingos Phoenicopterus roseus between Mediterranean colonies. Ardeola, 71: 43-60. Las variaciones en la calidad del hábitat en el espacio y el tiempo llevan a las aves a rastrear estos cambios para optimizar su estado físico. Investigamos los movimientos entre colonias de los flamencos comunes Phoenicopterus roseus entre colonias de cría del norte del Mediterráneo, establecidas desde hace décadas, y una nueva colonia de cría en el sur del Mediterráneo, en un sitio bastante impredecible (Ezzemoul, Argelia). Entre los flamencos observados como reproductores en Ezzemoul en 2006 y 2009, 59 y 26 individuos anillados, respectivamente, fueron observados antes durante la misma temporada de cría en otra colonia del norte del Mediterráneo y posteriormente en la colonia del sur del Mediterráneo, proporcionando así la primera evidencia de desplazamientos a gran escala dentro de la temporada (> 1.000 km) de una colonia a otra. Sugerimos que el fracaso de la cría y una densidad de nidos mucho mayor en las colonias del norte, establecidas desde hace mucho tiempo, desencadenaron estos movimientos. El éxito reproductivo y la condición corporal de los polluelos en Ezzemoul fueron mayores que en Fuente de Piedra (España), lo que indica que a gran escala espacial y en un marco de tiempo más largo, el éxito de reproducción dependiente de la densidad en las colonias de flamencos comunes puede inducir un cambio de una distribución despótica ideal a una distribución libre ideal.—Boucheker, A., Nedjah, R., Boulkhssaïm, M., Germain, Ch., Garrido, A., Rendón, M.A., Amat, j.A., Rendón-Martos, M., Prodon, R., Béchet, A. y Samraoui, B. (2024). Rastreando cambios y desplazamientos entre sitios de nidificación: Desplazamientos de flamencos comunes Phoenicopterus roseus entre colonias mediterráneas dentro de la temporada de cría. Ardeola, 71: 43-60. [ABSTRACT FROM AUTHOR]

At the end of the Pleistocene as temperatures warmed, new habitats opened up to human occupation as the Fennoscandian Ice Sheet receded. Along the west coast of modern-day Norway, human populations of coastal foragers slowly transitioned from short-term settlement patterns in the Early Mesolithic (ca. 11,500–10,000 cal BP), to more lasting ones during the Late Mesolithic (8500-6000 BP) and Early Neolithic (ca. 6000–5200 BP) as climatic conditions improved and stabilized. Here, using spatially and temporally resolved archaeological observations, paleoclimate data, and a spatiotemporal species distribution model, we test whether a) improvements in climate resulted in expansion of the available human niche space allowing for human population growth, and b) whether increasing population densities and ensuing deprecation of habitat suitability pushed people into occupying successively lower ranked habitats as predicted by the Ideal Free Distribution model. We find that a) climate gradually improved and stabilized during the Holocene, with the effect of improving general habitat suitability, which in turn led to an increase in human population size, b) that immediate proximity to sheltered coastal areas was central to settlement decisions but that c) increasing populations did not drive dispersal patterns into lower ranked habitats. The latter is likely attributable to the general improvements in habitat suitability due to the warming climate and the relative abundance of coastal habitats found in Norway.

Competition typically takes place in a spatial context, but eco-evolutionary models rarely address the joint evolution of movement and competition strategies. Here we investigate a spatially explicit forager-kleptoparasite model where consumers can either forage on a heterogeneous resource landscape or steal resource items from conspecifics (kleptoparasitism). We consider three scenarios: (1) foragers without kleptoparasites, (2) consumers specializing as foragers or as kleptoparasites, and (3) consumers that can switch between foraging and kleptoparasitism depending on local conditions. We model movement strategies as individual-specific combinations of preferences for environmental cues, similar to step-selection coefficients. Using mechanistic, individual-based simulations, we study the joint evolution of movement and competition strategies, and we investigate the implications for the distribution of consumers over this landscape. Movement and competition strategies evolve rapidly and consistently across scenarios, with marked differences among scenarios, leading to differences in resource exploitation patterns. In scenario 1, foragers evolve considerable individual variation in movement strategies, while in scenario 2, movement strategies show a swift divergence between foragers and kleptoparasites. In scenario 3, where individuals' competition strategies are conditional on local cues, movement strategies facilitate kleptoparasitism, and individual consistency in competition strategy also emerges. Even in the absence of kleptoparasitism (scenario 1), the distribution of consumers deviates considerably from predictions of ideal free distribution models because of the intrinsic difficulty of moving effectively on a depleted resource landscape with few reliable cues. Our study emphasizes the advantages of a mechanistic approach when studying competition in a spatial context and suggests how evolutionary modeling can be integrated with current work in animal movement ecology. [ABSTRACT FROM AUTHOR]

The analysis of site locations is an important component of archaeological research. Recent advances in this topic include the use of ecological models such as the ideal free distribution and its variants, which predict site locations under various conditions in relation to criteria that promote the greatest adaptive success. Such models can face problems in determining such criteria and especially their relative importance. Another approach, which can be used in conjunction with these models, uses the concept of decision trees to infer the relative ranking and the hierarchy of the role of different criteria in the actual locational decisions underlying site placement. Examples from ethnography and European archaeology demonstrate this approach and additionally allow the consideration of another issue, the contexts in which site function and location are likely to be strongly correlated. [ABSTRACT FROM AUTHOR]

There is an increasing need to understand how animals respond to modifications of their habitat following landscape‐scale disturbances such as wildfire or timber harvest. Such disturbances can promote increased use by herbivores due to changes in plant community structure that improve forage conditions, but can also cause avoidance if other habitat functions provided by cover are substantially reduced or eliminated. Quantifying the total effects of these disturbances, however, is challenging because they may not fully be apparent unless observed at successional timescales. Further, the effects of disturbances that improve habitat quality may be density dependent, such that the benefits are (1) less valuable to high‐density populations because the per‐capita benefits are reduced when shared among more users or, alternatively, (2) more valuable to animals living in high densities because resources may be more depleted from the greater intraspecific competition. We used 30 years of telemetry data on elk occurring at two distinct population densities to quantify changes in space use at diel, monthly, and successional timescales following timber harvest. Elk selected logged areas at night only, with selection strongest during midsummer, and peak selection occurring 14 years post harvest, but persisting for 26–33 years. This pattern of increased selection at night following a reduction in overhead canopy cover is consistent with elk exploiting improved nutritional conditions for foraging. The magnitude of selection for logged areas was 73% higher for elk at low population density, consistent with predictions from the ideal free distribution. Yet elk avoided these same areas during daytime for up to 28 years post logging and instead selected untreated forest, suggesting a role for cover to meet other life history requirements. Our results demonstrate that while landscape‐scale disturbances can lead to increased selection by large herbivores and suggest that the improvement in foraging conditions can persist over short‐term successional timescales, the magnitude of the benefits may not be equal across population densities. Further, the enduring avoidance of logging treatments during the daytime indicates a need for structurally intact forests and suggests that a mosaic of forest patches of varying successional stages and structural completeness is likely to be the most beneficial to large herbivores. [ABSTRACT FROM AUTHOR]

The strong Allee effect plays an important role on the evolution of population in ecological systems. One important concept is the Allee threshold that determines the persistence or extinction of the population in a long time. In general, a small initial population size is harmful to the survival of a species since when the initial data is below the Allee threshold the population tends to extinction rather than persistence. Another interesting feature of population evolution is that a species whose movement strategy follows a conditional dispersal strategy is more likely to persist. In other words, the biased movement can be a benefit for the persistence of the population. The coexistence of the above two conflicting mechanisms makes the dynamics rather intricate. However, some numerical results obtained by Cosner and Rodriguez [SIAM J. Appl. Math., 81 (2021), pp. 407--433] show that the directed movement can invalidate the strong Allee effect and help the population survive. To study this intriguing phenomenon, we consider the pattern formation and local dynamics for a class of single species population models that is subject to the strong Allee effect. We first rigorously show the existence of multiple localized solutions when the directed movement is strong enough. Next, the spectrum analysis of the associated linear eigenvalue problem is established and used to investigate the stability properties of these interior spikes. This analysis proves that there exists not only unstable but also linear stable steady states. Then, we extend results of the single equation to coupled systems and also construct several nonconstant steady states and analyze their stability. Finally, numerical simulations are performed to illustrate the theoretical results. [ABSTRACT FROM AUTHOR]

The diel vertical migration is one of the main drivers of population dynamics in the ocean. Population dynamical models of the ocean typically do not incorporate the behavioral aspects of the migration. We demonstrate a model with coupled population dynamics and behavior with the diel vertical migration emerging. We study the population dynamics and behavioral dynamics of a predator–prey system. We impose a cost of motion for both consumers and prey, and model each individual as following an Itô stochastic differential equation. We study the fixed-points of the ecosystem. Our modeling shows that as we increase the basal resource load, the strength of the diel vertical migration increases, as well as maximal velocity. In addition, a bimodal pattern emerges both for predators and consumers. The increase in the magnitude of the diel vertical migration causes a change in the allocation of copepod resources. • The diel migration is shown to be linked to productivity. • We couple mean-field games and population dynamics. • The ideal free distribution emerges from a mean-field game. [ABSTRACT FROM AUTHOR]

We consider an agro-ecologically motivated coupling between a prey-predator system and a vector-borne epidemic system. The coupled system contains one ODE, two reaction-diffusion PDEs, and one reaction-diffusion--advection PDE; it has no complete variational or monotonic structure and coefficients are spatially heterogeneous. We study the long-time behavior of solutions of the Cauchy--Neumann problem, which turns out to be largely decided by a linear stability criterion but still involves nonlinear subtleties. Then we consider an optimal control problem. Although it remains elusive analytically, we show numerically the variety of outcomes and the strong impact of the initial conditions. [ABSTRACT FROM AUTHOR]

Breeding habitat selection is a critical component of the annual cycle because of its effect on fitness. Multiple theories of habitat selection can be differentiated by their responses to the quantity of habitat, conspecific density, and habitat quality. Here, we use network analysis to understand the characteristics of fine‐scale breeding habitat selected by both immigrant and returning adult piping plovers (Charadrius melodus) to test five hypotheses of habitat selection. Between 2014 and 2019, we recorded 2034 uniquely marked adults breeding at 326 breeding locations with 1240 successive breeding events. Among adults, immigration events (i.e., individuals that moved to a new breeding location) were detected as often as fidelity to the same breeding location. We found support for the social attraction hypothesis for both immigrants and returners, indicating that adult plovers use social cues for settlement decisions. Adult plovers selected habitats with intermediate levels of conspecific density and high habitat quality, as assessed by con‐ and heterospecific nest survival, with no effect from the amount of available habitat. We also simulated the loss of breeding habitat and identified highly connected breeding locations, which occurred mostly on the riverine habitat type, which have important implications for habitat conservation for this listed species. Our results highlight the role of conspecifics at identifying high‐quality breeding habitat regardless of whether individuals return to the same breeding site or immigrate to new areas. [ABSTRACT FROM AUTHOR]

Changes in social organization accelerated on California's northern Channel Islands beginning around 1300 cal BP. These changes were associated with shifts in settlement and subsistence patterns related in part to drought conditions during the Medieval Climatic Anomaly (MCA; 1150-600 cal BP). By the end of the MCA, settlement patterns demonstrate evidence for territoriality and can be described by the ideal despotic distribution. The occupants of the most productive habitats prevented new settlers from moving in and accessing the available resources. We use faunal data from five sites on western Santa Rosa Island (CA-SRI-15, -31, −97, −313, and −333) to trace changes in settlement and population aggregation through this period. Fishing, which can support higher population densities than harvesting shellfish, increased overall from the Middle (2550-800 cal BP) to Late Period (650-168 cal BP), but there were fewer settlement sites on western Santa Rosa Island. In the centuries before the Middle to Late Period Transition (MLT; 800-650 cal BP), people occupied sites geographically dispersed along the west coast of the island. After the MLT, fishing was restricted to fewer large coastal villages. We argue that environmental stress and an increase in warfare on the northern Channel Islands drove the growth of more permanent consolidated villages, the development of territoriality, and settlement patterns consistent with greater resource defense and therefore a more despotic distribution.

Changes in social organization accelerated on California's northern Channel Islands beginning around 1300 cal BP. These changes were associated with shifts in settlement and subsistence patterns related in part to drought conditions during the Medieval Climatic Anomaly (MCA; 1150-600 cal BP). By the end of the MCA, settlement patterns demonstrate evidence for territoriality and can be described by the ideal despotic distribution. The occupants of the most productive habitats prevented new settlers from moving in and accessing the available resources. We use faunal data from five sites on western Santa Rosa Island (CA-SRI-15, -31, −97, −313, and −333) to trace changes in settlement and population aggregation through this period. Fishing, which can support higher population densities than harvesting shellfish, increased overall from the Middle (2550-800 cal BP) to Late Period (650-168 cal BP), but there were fewer settlement sites on western Santa Rosa Island. In the centuries before the Middle to Late Period Transition (MLT; 800-650 cal BP), people occupied sites geographically dispersed along the west coast of the island. After the MLT, fishing was restricted to fewer large coastal villages. We argue that environmental stress and an increase in warfare on the northern Channel Islands drove the growth of more permanent consolidated villages, the development of territoriality, and settlement patterns consistent with greater resource defense and therefore a more despotic distribution.

Abstract Breeding habitat selection is a critical component of the annual cycle because of its effect on fitness. Multiple theories of habitat selection can be differentiated by their responses to the quantity of habitat, conspecific density, and habitat quality. Here, we use network analysis to understand the characteristics of fine‐scale breeding habitat selected by both immigrant and returning adult piping plovers (Charadrius melodus) to test five hypotheses of habitat selection. Between 2014 and 2019, we recorded 2034 uniquely marked adults breeding at 326 breeding locations with 1240 successive breeding events. Among adults, immigration events (i.e., individuals that moved to a new breeding location) were detected as often as fidelity to the same breeding location. We found support for the social attraction hypothesis for both immigrants and returners, indicating that adult plovers use social cues for settlement decisions. Adult plovers selected habitats with intermediate levels of conspecific density and high habitat quality, as assessed by con‐ and heterospecific nest survival, with no effect from the amount of available habitat. We also simulated the loss of breeding habitat and identified highly connected breeding locations, which occurred mostly on the riverine habitat type, which have important implications for habitat conservation for this listed species. Our results highlight the role of conspecifics at identifying high‐quality breeding habitat regardless of whether individuals return to the same breeding site or immigrate to new areas.

Although it is well established that density dependence drives changes in organismal abundance over time, relatively little is known about how density dependence affects variation in abundance over space. We tested the hypothesis that spatial trade‐offs between food and safety can change the drivers of population distribution, caused by opposing patterns of density‐dependent habitat selection (DDHS) that are predicted by the multidimensional ideal free distribution. We addressed this using winter aerial survey data of northern Yellowstone elk (Cervus canadensis) spanning four decades. Supporting our hypothesis, we found positive DDHS for food (herbaceous biomass) and negative DDHS for safety (openness and roughness), such that the primary driver of habitat selection switched from food to safety as elk density decreased from 9.3 to 2.0 elk/km2. Our results demonstrate how population density can drive landscape‐level shifts in population distribution, confounding habitat selection inference and prediction and potentially affecting community‐level interactions. [ABSTRACT FROM AUTHOR]

Local ecological knowledge informs how natural resource patches are identified and valued across a landscape by communities that rely on them. However, local knowledge is not always considered in quantitative models evaluating resource access and quality. Based on ethnographic fieldwork in southwest China, I integrate ecological, economic, and cultural factors to model non-timber forest product distribution and resource access in a community-based forest governance system. Observations over four mushroom harvesting seasons suggest that the distribution of harvesters relative to available resources follows the expected distribution under an ideal free distribution (IFD). An emergent ideal free distribution is significant as it may offer evidence of sustainable and equitable resource management. Moreover, this case offers an extension of the IFD by basing model parameters on locally-determined forest values and knowledge rather than predominantly environmental variables. Finally, results reaffirm that local forest management systems with adaptive property rights and redistributive norms offer multiple benefits for addressing resource governance challenges. [ABSTRACT FROM AUTHOR]

Since its inception, attempts have been made to improve ideal free distribution (IFD) theory to make it better fit real-world data. Spatial contagion is a newer ecological concept that suggests that the perceived quality of a patch can be affected by the quality of its neighbor patches. Here, we present a series of experiments testing for potential contagion effects, examining how contagion can interact with the IFD and determining whether spatial context affects assessment of habitat quality. First, we tested whether the presence of conspecific competitors negatively impacts oviposition habitat selection by female mosquitoes (Culex restuans). We then used a more complex spatial landscape to determine whether competition can create a spatial contagion effect. Finally, we examined whether the density of conspecifics can adjust the contagion effect of nutrient availability. While females avoided patches containing conspecifics, there was no effect of competition/density on neighboring patches. Additionally, we found that resource availability was a significant predictor of where egg rafts were laid, but resource availability did not have a contagion effect. These results provide further support for the utility of the IFD, as individuals were able to accurately assess patch-level habitat quality. [ABSTRACT FROM AUTHOR]

The Ideal Free Distribution suggests the relative allocation of the number of organisms foraging across two or more resource sites will match the relative density of reinforcement patches in those resource sites. This initial project sought to develop a new method of foraging research for dogs by using a commercially available treat dispenser in basic behavioral research. The purpose of this study was to determine whether the Ideal Free Distribution equation could describe the behavior of the domesticated dog in a daycare setting. Toward this end, we recorded dog behavior in a free operant arrangement on various variable‐time schedules of reinforcement. Results indicated matching occurred in the dog sample, which corresponded with the Ideal Free Distribution equation, with a slight visual appearance toward undermatching, consistent with extant literature on group foraging. Furthermore, there was a lack of bias in the current sample of foraging dogs. Implications and future directions involve extending foraging research in the domesticated dog. That the study occurred in a local dog daycare specifically highlights how practical concerns in animal welfare and/or training can be addressed in rigorous ways with strong conceptual foundations in the experimental analysis of behavior. [ABSTRACT FROM AUTHOR]

For the two-patch logistic model, we study the effect of dispersal intensity and dispersal asymmetry on the total population abundance and its distribution. Two complete classifications of the model parameter space are given: one concerning when dispersal causes smaller or larger total biomass than no dispersal, and the other addressing how the total biomass changes with dispersal intensity and dispersal asymmetry. The dependencies of the population abundance of each individual patch on dispersal intensity and dispersal asymmetry are also fully characterized. In addition, the maximal and minimal total population sizes induced by dispersal are determined for the logistic model with an arbitrary number of patches, and a weak order-preserving result correlated the local population abundances with and without dispersal is established. • The total biomass of the two-patch logistic model at positive equilibrium is studied. • Two complete classifications of the model parameter space in terms of dispersal rate and dispersal asymmetry are given. • The changing pattern of the population size of each individual patch is characterized. • The maximal and minimal total biomasses induced by dispersal are determined. • A weak order-preserving result correlated the local population abundances with and without dispersal is obtained. [ABSTRACT FROM AUTHOR]

Interactions among individuals of the same species inform us about resource value and sociality; however, for species that are difficult to observe directly, these behaviours are potentially missed or misinterpreted via remote monitoring approaches. Here, we investigated how agonistic interactions influenced temporal and spatial variation in the social structuring of loggerhead sea turtles, Caretta caretta , foraging on sponges at a reef (Zakynthos, Greece) over multiple years. We directly observed individuals via snorkel surveys (with photoidentification and videos) supported by aerial drone surveys. Most turtles were immature loggerheads, of which half were detected in more than 1 year. Individual loggerheads occupied distinct (very small) patches on the reef, with low overlap when foraging. Interactions generally occurred when loggerheads were adjacent to, or passing through, patches occupied by other individuals. Interactions between loggerheads represented an extremely small fraction of the activity budget, but potentially consumed two to three times more energy than swimming and foraging. Escalation of aggression, unexpectedly, skipped the passive (evaluation) phase in half of interactions (starting with biting and chasing), with contests being primarily won by more aggressive individuals, independent of body size and duration of presence (i.e. reef occupancy in years). Distinct hierarchical structuring was detected based on win outcomes and spatial area use within each year; however, the number and combination of turtles frequenting the reef varied across years, with individuals only dominating for 2–3 years before departing (or returning intermittently) and being replaced. The unexpected fight dynamics and regularly changing hierarchies indicate that individuals perceived the resource value of sponges differently, which was attributed to differences in their ability to assess resource abundance and/or availability of resources at alternative sites. Our results contribute to the emerging field of sociality in reptiles. • Interactions represented 1% of the activity budget of foraging loggerhead turtles. • Interactions appeared more energetically costly than swimming or foraging. • Interactions were immediately aggressive (no passive evaluation) in 48% of cases. • Winners were the most aggressive, independent of body size or years of presence. • Individuals remained dominant for 2–3 years only before leaving or, rarely, returning. [ABSTRACT FROM AUTHOR]

In this paper, we use an integrodifference equation model and pairwise invasion analysis to find what dispersal strategies are evolutionarily stable strategies (also known as evolutionarily steady or ESS) when there is spatial heterogeneity and possibly seasonal variation in habitat suitability. In that case there are both advantages and disadvantages of dispersing. We begin with the case where all spatial locations can support a viable population, and then consider the case where there are non-viable regions in the habitat. If the viable regions vary seasonally, and the viable regions in summer and winter do not overlap, dispersal may really be necessary for sustaining a population. Our findings generally align with previous findings in the literature that were based on other modeling frameworks, namely that dispersal strategies associated with ideal free distributions are evolutionarily stable. In the case where only part of the habitat can sustain a population, we show that a partial occupation ideal free distribution that occupies only the viable region is associated with a dispersal strategy that is evolutionarily stable. As in some previous works, the proofs of these results make use of properties of line sum symmetric functions, which are analogous to those of line sum symmetric matrices but applied to integral operators. [ABSTRACT FROM AUTHOR]

Human populations distribute themselves across landscapes in clearly patterned ways, but accurate and theoretically informed predictions and explanations of that patterning in the archaeological record can prove difficult. Recently, archaeologists have begun applying a unifying theoretical framework derived from population and behavioural ecology to understand human population distribution and movement: the ideal distribution model (IDM). The three variants of this IDM - the ideal free distribution, the ideal free distribution with an Allee effect, and the ideal despotic distribution - are capable of generating testable hypotheses concerning the colonisation of landscapes, the spatial distribution of populations, cooperation and competition, social hierarchy and inequality, and the impacts of subsistence on settlement patterns. Their success in addressing such wide-ranging research questions demonstrates that IDMs are not only helpful for analysing settlement patterns in relation to environmental factors, but for better understanding the social forces that impact population distribution, as well. There seem to be no geographic or temporal bounds to the utility of IDMs, and we look forward to the application of these models in ever more diverse settings. [ABSTRACT FROM AUTHOR]

The colonisation of North America and subsequent adaptation to climate change are major research foci in the American Southeast. Here, we used the Ideal Free Distribution from Behavioural Ecology and projections of fossil pollen to generate predictions for landscape use. We tested these predictions against the distribution of previously recorded projectile points in the Paleoindian Database of the Americas and archaeological sites in the Digital Index of North American Archaeology for the Tennessee River drainage from the appearance of Clovis sites in the terminal Pleistocene though the Late Holocene (∼13,250–3,000 cal BP). We found that the distribution of points and sites were initially skewed towards lower elevations, and then spread to higher elevations over the course of the Younger Dryas into the Middle Holocene, which is consistent with predictions of the Ideal Free Distribution. However, during the Middle Holocene, sites are more clustered, which is consistent with a shift to an Ideal Free Distribution with Allee effect that was likely driven by a broader distribution of oak–hickory forests. Finally, the distribution of sites after the Middle Holocene was more dispersed, which is consistent with a shift to an Ideal Despotic Distribution. [ABSTRACT FROM AUTHOR]

How might subsistence strategies structure the costs and benefits of habitat selection and, therefore, drive settlement patterning? We explore this question within an Ideal Distribution framework, arguing that (i) a habitat can be decomposed into its environmental covariates, (ii) their relative contributions to suitability can vary as a function of subsistence strategy, and (iii) the resulting differences will in turn lead to different population distributions across habitats. To evaluate these claims, we apply a Poisson point-process modelling approach known as maximum entropy (MaxEnt) to Archaic hunter-gatherer and Formative maize-farmer sites within the Grand Staircase-Escalante National Monument. Our results show that environmental covariates vary in their importance for each strategy and that the strategies themselves vary in their land use and habitat distribution, with Archaic foragers being widely distributed across space, Formative farmers more densely packed into areas indicative of higher maize productivity. The approach itself also has wide application to other subsistence strategies, including horticulture and pastoralism, across a range of environmental conditions. [ABSTRACT FROM AUTHOR]

This paper offers a new numerical approach to model the effects of archaeological site placement and population density on environmental suitability using two ecological models, the Ideal Free Distribution (IFD) and Ideal Despotic Distribution (IDD), treating the Oued Loukkos in northern Morocco as an example. This method incorporates local resource depletion with increasing population density consistent with the predictions of the IFD. It also incorporates the potential for the exclusion of part of the population from certain productive areas consistent with the IDD. In this study, we propose a dynamic approach to the impact of site placement on habitat suitability and therefore broader application for understanding changes in settlement distribution with population density through time. Furthermore, resulting settlements can be parameterized by a Zipf-Mandelbrot distribution, entailing a direct relationship between the ecological, demographic, and political factors and the resulting rank-size distribution of sites. This approach allows for a broader range of applications among foraging and agricultural economies. [ABSTRACT FROM AUTHOR]

Recent research emphasises the importance of both within-group cooperation and between-group competition for human sociality, past and present. We hypothesise that the shift from foraging to food production in eastern North America provided novel socioecological conditions that impacted interpersonal and intergroup interactions in the region, inspiring both greater cooperation as well as competition. We predict that (1) successful exploitation of this indigenous crop complex encouraged greater cooperation leading to site aggregation in high-quality locations as expected by an ideal free distribution with an Allee effect, and (2) continued population growth driven by the domestication and adoption of the crop complex eventually inspired a shift from positive to negative density dependent settlement dynamics, driving declines in site suitability. Our results demonstrate that there was an increase in both site clustering and site location quality coincident with crop management and domestication in the Middle Holocene, and that territorial violence appears at this time as well. Site quality later declined after c. 3000 cal BP, also as predicted. These results indicate that managing and domesticating plants inspired an Allee effect and led to greater within-group cooperation, but was also related to the rise of territorial between-group competition in the region. [ABSTRACT FROM AUTHOR]

We apply the Ideal Free Distribution (IFD) and Ideal Despotic Distribution (IDD) models to two Bronze Age (ca. 3100–1050 BCE) mainland Greek regions with different local ecologies and culture histories: Messenia and the Argolid. Using existing settlement data, we show that regions within the same cultural system contemporaneously fit different settlement patterns, reflecting distinct environmental adaptations. Such differences help to understand regional variations in resource access and competition. Although the highest-ranked habitats were settled first in each region, large-scale expansion to lower-ranked habitats occurred more quickly in the Argolid, likely because highly productive agricultural land was limited, resulting in a competitive focus on the Argive Plain. This contrasts with Messenia, where access to agricultural resources is better distributed. Our results demonstrate that applying ideal distribution models at a regional scale provides valuable information about the development of social complexity and the conditions in which it occurs. [ABSTRACT FROM AUTHOR]

Migration is a tactic used across taxa to access resources in temporally heterogenous landscapes. Populations that migrate can attain higher abundances because such movements allow access to higher quality resources, or reduction in predation risk resulting in increased fitness. However, most migratory species occur in partially migratory populations, a mix of migratory and non‐migratory individuals. It is thought that the portion of migrants in a partial migration population is maintained either through (1) a population‐level evolutionary stable state where counteracting density‐dependent vital rates act on migrants and residents to balance fitness or (2) conditional migration, where the propensity to migrate is influenced by the individual's state. However, in many respects, migration is also a form of habitat selection and the proportion of migrants and residents may be the result of density‐dependent habitat selection. Here, we test whether the theory of Ideal Free Distribution (IFD) can explain the coexistence of different migratory tactics in a partially migratory population. IFD predicts individuals exhibit density‐dependent vital rates and select different migratory tactics to maximize individual fitness resulting in equal fitness (λ) between tactics. We tested the predictions of IFD in a partially migratory elk population that declined by 70% with 19 years of demographic data and migratory tactic switching rates from >300 individuals. We found evidence of density dependence for resident pregnancy and adult female survival providing a fitness incentive to switch tactics. Despite differences in vital rates between migratory tactics, mean λ (fitness) was equal. However, as predicted by the IFD, individuals switched tactics toward those of higher fitness. Our analysis reveals that partial migration may be driven by tactic selection that follows the ideal free distribution. These findings reinforce that migration across taxa may be a polymorphic behavior in large herbivores where migratory tactic selection is determined by differential costs and benefits, mediated by density dependence. [ABSTRACT FROM AUTHOR]

The article presents the discussion on overview of the evolutionary ramifications of the relation between animal personality and the ideal free distribution (IFD). Topics include electronic supplementary material, DiNuzzo & Griffen showing some simulation results for a scenario with temporally varying patch quality; and optimal behaviour of a polymorphic population deviating considerably from the IFD of a monomorphic population.

Abstract Spatial distribution and habitat selection are integral to the study of animal ecology. Habitat selection may optimize the fitness of individuals. Hutchinsonian niche theory posits the fundamental niche of species would support the persistence or growth of populations. Although niche‐based species distribution models (SDMs) and habitat suitability models (HSMs) such as maximum entropy (Maxent) have demonstrated fair to excellent predictive power, few studies have linked the prediction of HSMs to demographic rates. We aimed to test the prediction of Hutchinsonian niche theory that habitat suitability (i.e., likelihood of occurrence) would be positively related to survival of American beaver (Castor canadensis), a North American semi‐aquatic, herbivorous, habitat generalist. We also tested the prediction of ideal free distribution that animal fitness, or its surrogate, is independent of habitat suitability at the equilibrium. We estimated beaver monthly survival probability using the Barker model and radio telemetry data collected in northern Alabama, United States from January 2011 to April 2012. A habitat suitability map was generated with Maxent for the entire study site using landscape variables derived from the 2011 National Land Cover Database (30‐m resolution). We found an inverse relationship between habitat suitability index and beaver survival, contradicting the predictions of niche theory and ideal free distribution. Furthermore, four landscape variables selected by American beaver did not predict survival. The beaver population on our study site has been established for 20 or more years and, subsequently, may be approaching or have reached the carrying capacity. Maxent‐predicted increases in habitat use and subsequent intraspecific competition may have reduced beaver survival. Habitat suitability‐fitness relationships may be complex and, in part, contingent upon local animal abundance. Future studies of mechanistic SDMs incorporating local abundance and demographic rates are needed.

Abstract Density‐dependent competition for food reduces vital rates, with juvenile survival often the first to decline. A clear prediction of food‐based, density‐dependent competition for large herbivores is decreasing juvenile survival with increasing density. However, competition for enemy‐free space could also be a significant mechanism for density dependence in territorial species. How juvenile survival is predicted to change across density depends critically on the nature of predator–prey dynamics and spatial overlap among predator and prey, especially in multiple‐predator systems. Here, we used a management experiment that reduced densities of a generalist predator, coyotes, and specialist predator, mountain lions, over a 5‐year period to test for spatial density dependence mediated by predation on juvenile mule deer in Idaho, USA. We tested the spatial density‐dependence hypothesis by tracking the fate of 251 juvenile mule deer, estimating cause‐specific mortality, and testing responses to changes in deer density and predator abundance. Overall juvenile mortality did not increase with deer density, but generalist coyote‐caused mortality did, but not when coyote density was reduced experimentally. Mountain lion‐caused mortality did not change with deer density in the reference area in contradiction of the food‐based competition hypothesis, but declined in the treatment area, opposite to the pattern of coyotes. These observations clearly reject the food‐based density‐dependence hypothesis for juvenile mule deer. Instead, our results provide support for the spatial density‐dependence hypothesis that competition for enemy‐free space increases predation by generalist predators on juvenile large herbivores.

The standard model of a single population fragmented into two patches connected by migration, was first introduced in the 1970s by Freedman and Waltman, since generating long-term research interest, though its full analysis for arbitrary values of migration rate has only been completed relatively recently. Here, we present a model of two competing species in a two-patch habitat with migrations between patches. We derive equilibrium solutions of this model for three cases of migration rate resulting in isolated, well-mixed and semi-isolated habitats. We evaluate the full range of effects of habitat, life-history and migration parameters on population sizes. Finally, we add harvesting mortality and define conditions under which introduction of a no-harvesting (protected) area may lead to increased maximum sustainable yield. The results have applications in mixed fishery management and the design of wildlife protection zones, including marine protected areas (MPAs). • We consider a system of two competing populations with asymmetric migrations between two habitats. • We obtain equilibrium population sizes for zero, sufficiently small and infinite migration rates. • The coexistence condition for two competing species in a perfectly mixed habitat is derived. • Harvest mortality is added to the system and the maximum sustainable yield (MSY) is calculated. • The conditions under which a no-harvesting zone (e.g., marine protected area) can increase MSY are evaluated. [ABSTRACT FROM AUTHOR]

Major disturbances can temporarily remove factors that otherwise constrain population abundance and distribution. During such windows of relaxed top‐down and/or bottom‐up control, ungulate populations can grow rapidly, eventually leading to resource depletion and density‐dependent expansion into less‐preferred habitats. Although many studies have explored the demographic outcomes and ecological impacts of these processes, fewer have examined the individual‐level mechanisms by which they occur. We investigated these mechanisms in Gorongosa National Park, where the Mozambican Civil War devastated large‐mammal populations between 1977 and 1992. Gorongosa's recovery has been marked by proliferation of waterbuck (Kobus ellipsiprymnus), an historically marginal 200‐kg antelope species, which is now roughly 20‐fold more abundant than before the war. We show that after years of unrestricted population growth, waterbuck have depleted food availability in their historically preferred floodplain habitat and have increasingly expanded into historically avoided savanna habitat. This expansion was demographically skewed: mixed‐sex groups of prime‐age individuals remained more common in the floodplain, while bachelors, loners, and subadults populated the savanna. By coupling DNA metabarcoding and forage analysis, we show that waterbuck in these two habitats ate radically different diets, which were more digestible and protein‐rich in the floodplain than in savanna; thus, although individuals in both habitats achieved positive net energy balance, energetic performance was higher in the floodplain. Analysis of daily activity patterns from high‐resolution GPS‐telemetry, accelerometry, and animal‐borne video revealed that savanna waterbuck spent less time eating, perhaps to accommodate their tougher, lower‐quality diets. Waterbuck in savanna also had more ectoparasites than those in the floodplain. Thus, plasticity in foraging behavior and diet selection enabled savanna waterbuck to tolerate the costs of density‐dependent spillover, at least in the short term; however, the already poorer energetic performance of these individuals implies that savanna occupancy may become prohibitively costly as heterospecific competitors and predators continue to recover in Gorongosa. Our results suggest that behavior can provide a leading indicator of the onset of density‐dependent limitation and the likelihood of subsequent population decline, but that reliable inference hinges on understanding the mechanistic basis of observed behavioral shifts. [ABSTRACT FROM AUTHOR]

The wool carder bee Anthidium manicatum is one textbook example of resource defense polygyny among solitary bees, known for intense male–male competition, forced copulations, and the extreme form of interspecific territoriality toward other flower visitors. This mating system depends on the spatial structure of the defended resource and requires several adaptations in males. The allocation of patches with host plants as well as male body size and phenology was analyzed over 3 years in the diverse habitat of a botanical garden. Anthidium manicatum males searched in groups up to 12 individuals a wide diversity of patches with various food plants of foraging females. Territories were established in small high-quality patches only. Males abandoned aggressive and territorial behavior in large patches. Available patches were occupied by males of the various body size fractions independently of each other according to patch profitability. The higher competitive weight of large males in small patches compared to spacious ones was balanced by an opposing correlation of patch profitability. Although the mating system in A. manicatum is clearly a resource defense polygyny, males were found to be plastic in their behavior, and territoriality was not consistently observed. Mate acquiring tactics, be they territory holder (bourgeois), sneaker, floater, or scrambler for mating, can be considered to be different behavioral phenotypes within one environmentally sensitive conditional strategy. Significance statement: Territoriality is a rare and derived pattern in solitary bee mating behavior. In most cases of territoriality, males defend rendezvous places to meet freshly emerged, virgin females. While this type of mating behavior fits still into the framework of ancestral monandry of aculeate Hymenoptera, the continually polyandric resource defense polygyny found in the genus Anthidium is highly derived. Males occupy flower resources exploited for larval provisions and extort copulations from provisioning nesting females. Territoriality in Anthidium does not lead to a monopolization of females, the exclusion of many competitors from reproduction, and a reduction of sperm competition as is typical for resource-based mating systems. Contrary, Anthidium is a highly promiscuous species and both males and females are lifelong engaged in copulations with multiple mates. Also, the allocation of the resource fundamental to the defense polygyny was found to be more fairly balanced than expected. This study diversifies the mating system of anthidiine bees and demonstrates unusually high plasticity in the resource allocation of a territorial species. [ABSTRACT FROM AUTHOR]