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Transitions between patch states for a metapopulation living in a dynamic landscape. States 0, 1, and 2 correspond to patches being unsuitable and unoccupied, suitable and unoccupied, and suitable and occupied, respectively. Patch dynamics (solid black arrows) are governed by restoration rates of patches, l, and destruction rates of patches, b 1 and b 2 . Metapopulation dynamics (dashed gray arrows) are governed by colonization and extinction rates and e. c c b 1 2 2
Source publication
Abstract A challenge for conservation management is to understand how population and habitat dynamics interact to affect species persistence. In real landscapes, timing and duration of disturbances can vary, and species' responses to habitat changes will depend on how timing of dispersal and reproduction events relate to the landscape temporal stru...
Contexts in source publication
Context 1
... or unsuitable for colonization by a given species. Consequently, patches in a landscape are in one of three possible states, : unsuitable and un- S {0, 1, 2} occupied ( ), suitable and unoccupied ( ), and S p 0 S p 1 suitable and occupied ( ). The dynamics of habitat S p 2 suitability are determined by three parameters, l, b 1 , and b 2 ( fig. 1). Unsuitable patches become suitable at a rate l. Suitable patches may become unsuitable due to a mix- Populations in an occupied patch become extinct either because their patch becomes unsuitable or at a rate e due to other sources of local extinction, including disturbances unrelated to the habitat dynamics and demographic ex- ...
Context 2
... two types of changes in patch state. First, there are changes in state due to empty patches becoming suitable, empty patches becoming unsuitable, occupied patches be- coming unsuitable, local demographic extinction, or colo- nization from an occupied patch, which occur at rates l, b 1 , b 2 , e, and c 1 N 2 /N, respectively ( fig. 1). We interpret these rates roughly as follows: over a short time interval of length Dt, the probability at which an unsuitable patch becomes suitable is approximately lDt; the probabilities that occu- pied or unoccupied patches become unsuitable are ap- proximately b 1 Dt and b 2 Dt, respectively; and the probability that an occupied ...
Context 3
... occupancy for landscapes with a large number of patches, stochastic effects play a significant role in metapopulations with fewer patches. Stochastic effects also generate fluctuations of varying magnitudes around the mean-field equilibrium and ulti- mately determine metapopulation viability in landscapes with a finite number of patches (see fig. C1; figs. C1, C2 are available online). Using the stochastic model, we an- alyzed how different dispersal behaviors influence estab- lishment, the covariance structure of fluctuations between suitable unoccupied and occupied patches on the event of establishment (i.e., spatiotemporal variance in patch oc- cupancy), and persistence times ...
Citations
... Dispersal within a patchy environment has important consequences for both pest management and species conservation [9,56], with dispersal being one of the main drivers of genetic diversity within insect species for example [102]. It is known to also play a vital role in insect survival and reproduction within such patchy landscapes [30,97]. In this section we will discuss the coupled models of [28] and [45]. ...
The internal behaviour of a population is an important feature to take account of when modelling its dynamics. In line with kin selection theory, many social species tend to cluster into distinct groups in order to enhance their overall population fitness. Temporal interactions between populations are often modelled using classical mathematical models, but these sometimes fail to delve deeper into the, often uncertain, relationships within populations. Here, we introduce a stochastic framework that aims to capture the interactions of animal groups and an auxiliary population over time. We demonstrate the model’s capabilities, from a Bayesian perspective, through simulation studies and by fitting it to predator–prey count time series data. We then derive an approximation to the group correlation structure within such a population, while also taking account of the effect of the auxiliary population. We finally discuss how this approximation can lead to ecologically realistic interpretations in a predator–prey context. This approximation also serves as verification to whether the population in question satisfies our various assumptions. Our modelling approach will be useful for empiricists for monitoring groups within a conservation framework and also theoreticians wanting to quantify interactions, to study cooperation and other phenomena within social populations.
... Moreover, environmental changes alter landscape structure at different temporal and spatial scales 30 . Earlier spatially implicit metapopulation models show that species persistence is highly sensitive to landscape dynamics 52,53 . In a metacommunity context, using an experimental system of only two sites, 45 showed that local population densities and species persistence exhibit different responses to periodic perturbations on local sites and that dispersal capabilities play a key role in the recovery of species after perturbations. ...
The stability of isolated communities depends on the complexity of their foodwebs. However, it remains unclear how local stability interacts with dispersal in multitrophic metacommunities to shape biodiversity patterns. This lack of understanding is deeper in the more realistic frame of landscapes that exhibit non-trivial and time-varying structures. Therefore, in this study, we aim to evaluate the influence of local stabilizing factors versus dispersal in determining the sensitivity of metacommunity biodiversity to increasing asynchrony of site availability. Additionally, we assess the role of foodweb complexity and landscape structure as modulating factors. To accomplish our goals we developed a model based on random matrices for local communities, which are linked by stochastic dispersal over explicit dynamic landscapes. We ran numerical simulations and computed the effect sizes of foodweb temperature, self-limitation, dispersal ability, and all pairwise combinations, on the sensitivity of biodiversity to landscape asynchrony. In our experiments we explored gradients of species richness, foodweb connectance, number of sites, and landscape modularity. Our results showed that asynchrony among site availability periods reduced $$\alpha$$ α -diversity and increased $$\beta$$ β -diversity. Asynchrony increased $$\gamma$$ γ -diversity at high dispersal rates. Both local and regional stabilizing factors determined the sensitivity of metacommunities to landscape asynchrony. Local factors were more influential in landscapes with fewer sites and lower modularity, as well as in metacommunities composed of complex foodwebs. This research offers insights into the dynamics of metacommunities in dynamic landscapes, providing valuable knowledge about the interplay between local and regional factors in shaping ecological stability and species persistence.
... Our methodology was interesting to estimate habitat availability over time and could be completed by testing the correlation between local connectivity metrics and species richness or abundance (Foltête et al., 2012b;Ribeiro et al., 2011). Indeed, landscape connectivity relies on the dispersal capacity of organisms, which shapes the distribution and persistence of populations (Hanski and Ovaskainen, 2000;Keyghobadi, 2007;Perry and Lee, 2019;Reigada et al., 2015). The dispersion of organisms also depends on their perception of the landscape (App et al., 2022;Baguette and Van Dyck, 2007;Balbi et al., 2021;Bélisle, 2005). ...
... The influence of disturbance on metapopulations is well-supported by theoretical studies (Ellner and Fussmann 2003;Johst and Drechsler 2003;Wilcox et al. 2006;Reigada et al. 2015). Field studies have also suggested that metapopulation dynamics are driven not only by the intensity and frequency of disturbance (Thomas et al. 2001;Hodgson et al. 2009;Johansson et al. 2017), but also by the years since disturbance (patch age) (Wahlberg et al. 2002;Schroeder et al. 2007;Caruso et al. 2010;Mutz et al. 2017). ...
It has been recognized that the timing of disturbance, in addition to its intensity and frequency, is important for the population dynamics of organisms because the impact of the disturbance depends on the life history stage at which it occurs (i.e., egg, larva, or adult). However, the effects of disturbance timing on consumer population dynamics have not been explored. This study simultaneously estimated the effects of mowing frequency and timing on the subpopulation dynamics of the endangered grassland butterfly, Plebejus argyrognomon . A two-year investigation of a metapopulation of P. argyrognomon consisting of approximately 150 habitat patches revealed that subpopulation size decreased with increasing mowing frequency, in addition to the positive effect of patch area and habitat connectivity. With the mowing frequency fixed at once per year, subpopulation size maximized when mowing occurred during the adult period in the previous generation, presumably due to reduced impact in the high-mobility adult stage. By mowing during this period, subpopulation size was maintained at several times higher than mowing during the larval period. It is suggested that disturbance timing should be incorporated into the conservation of metapopulations in human-managed landscapes.
Implications for insect conservation
Reducing mowing frequency is important for the conservation of P. argyrognomon . In addition, mowing during the adult stage is best suited for maintaining subpopulations.
... Generally, they agree that speciation with gene flow is feasible as long as migration does not overwhelm selection, which is more likely with a pulsed behavior. Likewise, metacommunity models have demonstrated that landscape dynamics with fluctuating connectivity can surprisingly increase the number of coexisting species (Herrera-Alsina et al., 2021;Palamara et al., 2023) and be beneficial to population persistence (Reigada et al., 2015, in this case, a pulsed dispersal model). Models considering mixed periods of contact and isolation tested against continuous migration, or isolation followed by prolonged contact, also corroborate the favorable impact of pulsedness on speciation and richness (He et al., 2019; Linck & Battey, 2019). ...
Geographic barriers can come and go depending on natural conditions. These fluctuations cause population cycles of expansion and contraction, introducing intermittent migrations that may not hinder speciation but rather promote diversification. Here, we study a neutral two-island speciation model with intermittent migration driven by sea-level fluctuations. Seabed depth modulates isolation and connection periods between the islands, with migration occurring during connection periods with a certain probability. Mating is restricted to genetically compatible individuals on the same island, and offspring inherit genomes from both parents through recombination. We observe speciation pulses that would not occur under strict isolation or continuous migration, with infrequent, temporary increases in species richness happening at different times depending on the combination of geographic settings and migration probability. The resulting dynamic patterns of richness exhibit contrasting behavior between connected and isolated scenarios, often including species that do not persist. Prolonged isolation can reduce richness to one species per island, resembling patterns commonly associated with archipelagos under sea-level fluctuations. Together with other studies, our results in out-of-equilibrium populations support the relevance of investigating the impact of variable migration on diversification, particularly in regions of high diversity.
... Moreover, environmental changes alter landscape structure at different temporal and spatial scales (Holyoak et al., 2020). Earlier spatially implicit metapopulation models show that species persistence is highly sensitive to landscape dynamics (Keymer et al., 2000;Reigada et al., 2015). In a metacommunity context, using an experimental system of only two sites, Altermatt et al. (2011a) showed that local population densities and species persistence exhibit different responses to periodic perturbations on local sites and that dispersal capabilities play a key role in the recovery of species after perturbations. ...
... For future research, our model can be easily extended to incorporate other relevant processes. For instance, it would be worth to introduce heterogeneity in site quality (Thompson and Gonzalez, 2017;Ryser et al., 2021;Ye and Wang, 2023), and dispersal gradients governed by physical (Altermatt et al., 2011b) or ecological Reigada et al. (2015) conditions. ...
The stability of isolated communities is determined by foodweb complexity.However, it is unclear how local stability interacts with dispersal in multitrophic metacommunities to shape biodiversity patterns. Furthermore, metacommunity dynamics in landscapes with non-trivial and dynamic structures are less understood.
vspace{8pt}\newlineObjectives: We aim to evaluate the influence of local stabilizing factors versus dispersalin determining the sensitivity of metacommunity biodiversity to increasing site availabilityasynchrony. Additionally, we assess the role of foodweb complexity and landscapestructure as modulating factors.
vspace{8pt}\newlineMethods: We developed a model based on random matrices for local communities, which are linked by stochastic dispersal over explicit dynamic landscapes. We ran numerical simulations and computed the effect sizes of foodweb temperature, self-limitation, dispersal ability, and all pairwise combinations, on the sensitivity of biodiversity to landscape asynchrony. We explored gradients of species richness, foodweb connectance, number of sites, and landscape modularity.
Asynchrony among site availability periods reduced \(\alpha\)-diversity and rose \(\beta\)-diversity. Asynchrony increased \(\gamma\)-diversity at high dispersal rates. Bothlocal and regional stabilizing factors determined the sensitivity of metacommunities to land-scape asynchrony. Local factors were more influential in landscapes with fewer sites andlower modularity. Local factors were particularly influential in metacommunities composed of complex foodwebs.
This research offers insights into the dynamics of metacommunitiesin dynamic landscapes, providing valuable knowledge about the interplay between local andregional factors in shaping ecological stability and species persistence. We delve into themechanisms underlying our results and discuss potential extensions of our study.
... vegetation) conditions are a prerequisite for a thriving bird community at any given site, there should also be a strong management focus on landscape-scale processes and connectivity. For our wetland system in Telangana, India, we encourage future work fitting mechanistic metapopulation models to our data (Hanski, 1997;Holmes et al., 2020;Reigada et al., 2015), which can be used to project the effects of potential future changes to the wetland network (e.g. draining or drying of existing wetlands, or creation of new wetlands) on bird diversity, thus informing conservation management. ...
Aim
Artificial island habitats such as human‐made wetlands are emerging novel ecosystems. Understanding the drivers of diversity in such artificial systems is essential for balancing the goals of biodiversity conservation and human socio‐economic needs.
Location
Telangana state, India.
Methods
We surveyed water birds in a network of 57 artificial wetlands and assessed four macroecological biodiversity patterns: spatial betadiversity, temporal betadiversity, species‐abundance distributions (SADs), and the species–area relationship (SAR). We employed a mix of phenomenological and mechanistic models to examine the four macroecological patterns. We hypothesized that the wetland bird communities are primarily structured by immigration–extinction dynamics and thus that spatial and temporal betadiversity would be high, the within‐wetland SADs would exhibit a large number of rare species and a monotonically declining overall shape, and that the SAR across wetlands would be strongly increasing.
Results
Spatial and temporal betadiversity were both high and mostly attributable to turnover rather than nestedness. While the pooled SAD exhibited an interior mode, the SAD for individual wetlands was generally log‐series distributed, consistent with a model in which immigration among wetlands is high. The SAR exhibited an increasing trend, with the ‘small‐island effect’, which reflects constraints on immigration and is often observed for true island archipelagos, being absent.
Main Conclusions
We tentatively conclude that bird diversity in this network of artificial wetlands is mainly structured by immigration–extinction dynamics, although we acknowledge that some of the patterns are also consistent with niche dynamics and future research should measure relevant biotic and abiotic variables in these wetlands. We encourage future work in which our rich dataset is used to fit dynamic models that permit more‐detailed quantitative inferences about mechanisms structuring diversity in this novel ecosystem, which can ultimately also inform conservation management.
... Generally, they agree that speciation with gene flow is feasible as long as migration does not overwhelm selection, which is more likely with a pulsed behavior. Likewise, metacommunity models have demonstrated that landscape dynamics with fluctuating connectivity can surprisingly increase the number of coexisting species [40] and be beneficial to populations persistence ( [41], in this case, a pulsed dispersal model). Models considering mixed periods of contact and isolation tested against continuous migration, or isolation followed by prolonged contact, also corroborate the favorable impact of pulsedness on speciation and richness [33,34]. ...
... Our work aligns with recent efforts emphasizing the significance of dynamic barriers and ephemeral effects to understanding complex environments [33,34,40,41], thereby emphasizing their relevance for conservation [63,64]. Further investigation to distinguish the indirect effects of varying migration, such as intra and interspecific genetic variability, hybridization, and reticulate evolution, would be a natural next step. ...
Geographic barriers prevent migration between populations, thereby facilitating speciation through allopatry. However, these barriers can exhibit dynamic behavior in nature, promoting cycles of expansion and contraction of populations. Such oscillations cause temporal variations in migration that do not necessarily prevent speciation; on the contrary, they have been suggested as a driving force for diversification. Here we present a study on a two-island neutral speciation model in scenarios with intermittent migration driven by sea-level fluctuations. Mating is constrained to genetically compatible individuals inhabiting the same island, and offspring inherit nuclear genomes from both parents with recombination. We observe pulses of speciation that would not occur in strict isolation or continuous migration. According to the seabed height, which modulates the duration of the isolation and connection periods, the maximum richness occurs at different times and in an ephemeral fashion. The expansion-contraction dynamics can accelerate diversification, but a long time in isolation can reduce the richness to one species per island, resembling patterns described by the taxon pulse hypothesis of diversification. Together with other studies, our results support the relevance of research on the impact of variable migration on diversification, suggested to be related to regions of high diversity.
... Patch dynamics have been addressed by numerous theoretical and empirical studies of metapopulations (Hanski 1999, Keymer et al. 2000, Cornell and Ovaskainen 2008, Drechsler and Johst 2010, Reigada et al. 2015. There are formulas for predicting patch occupancy of a single population in spatially explicit models characterized by temporal patch dynamics (Hanski 1999). ...
... Recent studies have shown that the rate of patch turnover is critical for metapopulation persistence. For example, increasing the rate of patch dynamics might decrease metapopulation persistence when dispersal is continuous, while persistence is facilitated by pulsed dispersal (Reigada et al. 2015). Evidence about the role of connectivity dynamics on species richness comes mostly from empirical studies of single-species metapopulations, where habitat connectivity is characterized by the landscape matrix (Eycott et al. 2012). ...
... Recent studies have shown that persistence in metapopulations is enhanced when dispersal is pulsed in landscapes with a high rate of patch turnover (Reigada et al. 2015). These results suggest that fluctuations in landscape connectivity, driven by migration pumps or pulses, could predict stronger deviations from static landscapes after accounting for both connectivity dynamics and patch turnover dynamics. ...
Biodiversity can increase in both high‐ and low‐connected landscapes. However, we lack predictions related to biodiversity dynamics when accounting for the temporal heterogeneity in the connections among the habitats of a landscape. Here, we study the relationship between fluctuations in landscape connectivity and biodiversity dynamics at local and regional scales. We contrast predictions about species richness between landscapes with and without fluctuations in connectivity. Our results show that local (α) and regional (γ) richness can increase together in dynamic landscapes characterized by periodic connectivity, clarifying empirical findings of high biodiversity in both low and high‐connected landscapes. Our results also suggest that fluctuations in connectivity increase the overall number of species coexisting in dynamic landscapes when compared with static landscapes with no fluctuations in connectivity. Extending metacommunity theory, by including fluctuations in landscape connectivity, can thus provide new testable predictions about species diversity across broad spatiotemporal scales in rapidly changing landscapes.
... DDG is an important means for preventing extinction, especially for populations that are dispersing in the absence of external immigration, from matrix habitat or marginal source patches, like for example in agricultural landscapes (Duelli and Obrist 2003). Ephemeral patch dynamics, whereby patches are sequentially restored and destroyed, play a significant role in allowing pest populations that undergo pulsed dispersal to persist (Reigada et al. 2015). Even in the presence of control strategies, such as the use of pesticides or the introduction of natural enemies, pests may exhibit what is referred to as the hydra effect, whereby increasing their mortality rate results in a positive contribution to population growth (McIntire and Juliano 2018; Costa and dos Anjos 2018). ...
Assessing the effects of a plant-host shift is important for monitoring insect populations over long time periods and for interventions in a conservation or pest management framework. In a heterogeneous environment, individuals may disperse between sources and sinks in order to persist. Here we propose a single-species two-patch model that aims to capture the generational movement of an insect that exhibits density-dependent dispersal, to see how shifting between hosts could alter its viability and asymptotic dynamics. We then analyse the stability and persistence properties of the model and further validate it using parameter estimates derived from laboratory experiments. In order to evaluate the potential of this model, we applied it to Drosophila suzukii (Diptera: Drosophilidae), which has become a harmful pest in several countries around the world. Although many studies have investigated the preference and attractiveness of potential hosts on this invasive drosophilid, no studies thus far have investigated whether a shift of fruit host could affect such a species’ ecological viability or spatiotemporal persistence. The model results show that a shift in host choice can significantly affect the growth potential and fecundity of a species such as D. suzukii, which ultimately could aid such invasive populations in their ability to persist within a changing environment.
