Patch Occupancy Research Articles

The effects of fragmentation per se on patch occupancy are stronger and more positive in a landscape with a higher quality and more homogeneous matrix

Habitat fragmentation per se ‐ independent of habitat amount ‐ often increases patch occupancy, possibly because patches are closer together in landscapes with higher fragmentation per se, which should increase dispersal success. Here, we ask whether this effect is influenced by the quality and/or heterogeneity of the landscape matrix, i.e. the non‐habitat portion of the landscape. Specifically, we expect the positive effect of fragmentation per seshould be accentuated when matrix quality is high, reducing dispersal mortality. In contrast, when matrix quality is low, high dispersal mortality should lead to fewer colonisations, and accumulation of extinctions across the smaller patches in a more‐fragmented landscape could lead to negative effects of fragmentation per se. Additionally, matrix heterogeneity could obscure fragmentation effects, as the link between habitat spatial distribution and between‐patch dispersal becomes less predictable. We test these ideas using Glanville fritillary butterfly Melitaea cinxia occupancy data for 4291 habitat patches in the Åland Islands, Finland. Habitat patches for the study species are discrete and well‐defined areas where at least one of the two host species occurs. Adult individuals disperse from habitat patches, spending time in the landscape matrix while searching for new habitat patches. Our predictions were mostly supported. Fragmentation effects were more strongly positive when matrix quality was high; however, we did not see the predicted negative effect of fragmentation per se in landscapes with low matrix quality. As predicted, fragmentation effects on patch occupancy were weaker in landscapes with a more heterogeneous matrix. Our findings may explain why fragmentation effects are often weak. They also suggest that the moderating effects of matrix quality and heterogeneity should be explicitly considered when interpreting effects of habitat fragmentation per se on species distributions.

Exploring resource patch occupancy: patch size, but not connectivity, explains the abundance of spider kleptoparasites in golden orb webs

Exploring resource patch occupancy: patch size, but not connectivity, explains the abundance of spider kleptoparasites in golden orb webs

Multi-generational dispersal and dynamic patch occupancy reveals spatial and temporal stability of seascapes

The success of non-native species (NNS) invasions depends on patterns of dispersal and connectivity, which underpin genetic diversity, population establishment and growth. In the marine environment, both global environmental change and increasing anthropogenic activity can alter hydrodynamic patterns, leading to significant inter-annual variability in dispersal pathways. Despite this, multi-generational dispersal is rarely explicitly considered in attempts to understand NNS spread or in the design of management interventions. Here, we present a novel approach to quantifying species spread that considers range expansion and network formation across time using the non-native Pacific oyster, Magallana gigas (Thunberg 1793), as a model. We combined biophysical modelling, dynamic patch occupancy models, consideration of environmental factors, and graph network theory to model multi-generational dispersal in northwest Europe over 13 generations. Results revealed that M. gigas has a capacity for rapid range expansion through the creation of an ecological network of dispersal pathways that remains stable through time. Maximum network size was achieved in four generations, after which connectivity patterns remained temporally stable. Multi-generational connectivity could therefore be divided into two periods: network growth (2000−2003) and network stability (2004–2012). Our study is the first to examine how dispersal trajectories affect the temporal stability of ecological networks across biogeographic scales, and provides an approach for the assignment of site-based prioritisation of non-native species management at different stages of the invasion timeline. More broadly, the framework we present can be applied to other fields (e.g. Marine Protected Area design, management of threatened species and species range expansion due to climate change) as a means of characterising and defining ecological network structure, functioning and stability.

Regional and local factors interact to shape colonization and extinction dynamics of invasive Hydrilla verticillata in a patchy landscape.

Understanding the response of species to global change requires disentangling the drivers of their distributions across landscapes. Colonization and extinction processes, shaped by the interplay of landscape-level and local patch-level factors, are key determinants of these distributions. However, disentangling the influence of these factors, when larger-scale processes manifest at local scales, remains a challenge. We addressed this challenge by investigating the colonization and extinction dynamics of the aquatic plant, Hydrilla verticillata, in a complex riverine rock pool system. This system, with hundreds of rock pools experiencing varying flooding frequencies, provided a natural laboratory to examine how a single landscape-level disturbance can differentially impact colonization and extinction depending on local patch characteristics to shape species distributions. Using 5 years of data across over 500 sites and more than 5000 surveys, we employed dynamic occupancy models to model colonization, extinction, and changes in Hydrilla patch occupancy while accounting for imperfect detection. Our results revealed that larger, infrequently flooded pools closer to the river were more likely to be colonized. In contrast, local extinction of Hydrilla was more likely in smaller pools closer to the river that flooded frequently. These findings underscore the importance of considering context-dependence in species distribution models. The same landscape-level disturbance (flooding) had opposing effects on colonization and extinction, with the direction and magnitude of these effects varying with local patch characteristics. Our study highlights the need for integrating local and landscape-level factors, and considering how larger-scale processes play out at the patch level, to understand the complex dynamics that shape species distributions.

The relative contributions of habitat area, configuration, and vegetative diversity on snake and lizard presence in agricultural landscapes

AbstractNearly one in five reptile species is at risk of extinction. Changes in habitat area, its configuration, and vegetation diversity could affect habitat use, but their relative importance is understudied. We assessed how these factors affected reptile presence in agricultural landscapes figure in Iowa, United States, using 695 cover boards visited 16,441 times in 2015–2020. Species‐wise encounter rates ranged 0.0001–0.012. Eight of 11 species and 54.2% of individuals were species of greatest conservation need. Habitat area, configuration, and vegetation diversity influenced reptile presence similarly. Mean patch occupancy was 0.18 for common garter snake (CG, Thamnophis sirtalis) and 0.45 for all snakes (AS). Naïve presence was explained by effort (odds ratio [OR]AS = 1.83, ORCG = 1.79), vegetation diversity (ORAS = 1.28, ORCG = 1.28), woody cover (ORAS = 1.24, ORCG = 1.41), and patch size (ORAS = 1.30). Large patch prairies were more likely to contain snakes than other conservation practices (encounter = 0.291), and more likely to contain CG (0.098) than prairie contour strips (0.031), waterways (0.018), grass contour strips (0.016), or terraces (0.015). While we documented low overall reptile presence, their higher presence in large prairie patches underscores the importance of core nature reserves for reptile conservation.

Broadening applications of stochastic patch occupancy models over three decades

AbstractAimStochastic patch occupancy models (SPOMs) are a type of spatial population simulation. They are arguably well‐suited to guide conservation in human‐altered landscapes, but their appropriateness for a wide range of species and landscape types has often been questioned. Here, we provide an overview of how SPOM research has expanded over the last three decades and discuss the untapped potential for these models to inform current conservation strategies.LocationWorldwide.MethodsWe carried out a systematic review of studies that have fitted SPOMs to real species and landscapes. We assessed temporal trends in SPOMs' use in conservation and management studies, their taxonomic and geographic coverage, and the attributes of studied landscapes. We quantitatively and qualitatively evaluated whether the authors' modelling choices reflected the perceived advantages and disadvantages of SPOMs.ResultsThe proportion of SPOMs used to answer conservation questions has increased over time. Questions of where, when and how to conserve have all been addressed, sometimes considering additional aspects such as cost‐effectiveness and climate change. Taxonomic diversity coverage has increased over time, and SPOMs have been used in landscapes with a higher proportion of suitable habitat. They have, however, been predominantly applied in temperate biomes. Few studies have explored parameter extrapolation in taxonomically and ecologically related species with mixed results.Main ConclusionsOver the past three decades, authors have exploited the simplicity and flexibility of SPOMs to answer a broad range of questions with practical implications. The use of SPOMs in less fragmented landscapes, and for an increasing range of taxa, suggests that the strictest definitions of their applicability can be challenged. Stochastic patch occupancy models have untapped potential for informing conservation under climate change. Given the urgent need to plan for large numbers of species with limited data for fitting, SPOMs could better fulfil their potential to guide conservation if parameters could be extrapolated to data‐deficient landscapes and species.

Habitat occupancy of the threatened Diademed Plover (Phegornis mitchellii) is not affected by llama grazing or peatland size, but declines with peatland humidity.

Many habitat-specialist organisms occur in distinct, patchy habitat, yet do not occupy all patches, and an important question is why apparently suitable habitat remains unoccupied. We examined factors influencing patch occupancy in near-threatened, little-known Diademed Plovers (Phegornis mitchellii), arguably the bird most specialized to life in High Andean peatlands. Andean peatlands are well-suited to occupancy modelling because they are discrete patches of humid habitat within a matrix of high-altitude steppe. We hypothesized that Diademed Plovers occupy preferably larger and more humid peatlands, and avoid peatlands used for grazing by llamas and vicuñas, which may trample vegetation and nests. From December 2021 to February 2022 (breeding season), we conducted plover occupancy surveys (2-4) on 40 peatlands at Lagunas de Vilama, a landscape of arid steppe and wetlands above 4,500 m in NW Argentina. We measured peatland size, grazing pressure, topographic and remotely-sensed variables that correlate with humidity, and incorporated these as covariates in occupancy models. Occupancy models showed that more than 50% of the studied peatlands were used by Diademed Plovers and most showed signs of reproduction, highlighting the importance of the Vilama Wetlands for Diademed Plover conservation. Within peatlands, Diademed Plovers were most often associated with headwaters. The top ranked occupancy model included constant detection, random spatial effects, and a single occupancy covariate: mean NDWI (Normalized Difference Water Index, an index correlated with water content and humidity) over the previous three years. Contrary to our prediction, Diademed Plovers preferred less water-saturated peatlands (lower NDWI), possibly to avoid nest flooding. This may be especially important in wet years, like the year when we conducted our surveys. Neither peatland size nor grazing by llamas and vicuñas affected peatland use by Diademed Plovers, suggesting that llama grazing at current levels may be compatible with plover conservation. For organisms that specialize on humid habitats, such as peatlands, factors affecting occupancy may vary temporally with variation in climate, and we recommend follow-up surveys across multi-year timescales to untangle the impact of climate on animals' use of humid habitats.

Predicting the spatial expansion of an animal population with presence-only data.

Predictive models can improve the efficiency of wildlife management by guiding actions at the local, landscape and regional scales. In recent decades, a vast range of modelling techniques have been developed to predict species distributions and patterns of population spread. However, data limitations often constrain the precision and biological realism of models, which make them less useful for supporting decision-making. Complex models can also be challenging to evaluate, and the results are often difficult to interpret for wildlife management practitioners. There is therefore a need to develop techniques that are appropriately robust, but also accessible to a range of end users. We developed a hybrid species distribution model that utilises commonly available presence-only distribution data and minimal demographic information to predict the spread of roe deer (Capreolus caprelous) in Great Britain. We take a novel approach to representing the environment in the model by constraining the size of habitat patches to the home-range area of an individual. Population dynamics are then simplified to a set of generic rules describing patch occupancy. The model is constructed and evaluated using data from a populated region (England and Scotland) and applied to predict regional-scale patterns of spread in a novel region (Wales). It is used to forecast the relative timing of colonisation events and identify important areas for targeted surveillance and management. The study demonstrates the utility of presence-only data for predicting the spread of animal species and describes a method of reducing model complexity while retaining important environmental detail and biological realism. Our modelling approach provides a much-needed opportunity for users without specialist expertise in computer coding to leverage limited data and make robust, easily interpretable predictions of spread to inform proactive population management.

The importance of patch shape at threshold occupancy: functional patch size within total habitat amount.

The habitat amount hypothesis (HAH) stresses the importance of total patch amount over the size of individual patches in determining species richness within a local landscape. However, the absence of some species from patches too small to contain a territory would be inconsistent with the HAH. Using the association of territory size with body size and the circle as optimal territory shape, we tested several HAH predictions of threshold patch occupancy and richness of 19 guilds of primarily insectivorous breeding birds. We characterized 16 guild-associated patch types at high spatial resolution and assigned one type to each guild. We measured functional patch size as the largest circle that fit within each patch type occurring in a local landscape. Functional patch size was the sole or primary predictor in regression models of species richness for 15 of the 19 guilds. Total patch amount was the sole or primary variable in only 2 models. Quantifying patch size at high resolution also demonstrated that breeding birds should be absent from patches that are too small to contain a territory and larger species should occur only in larger patches. Functional patch size is a readily interpretable metric that helps explain the habitat basis for differences in species composition and richness between areas. It provides a tool to assess the combined effects of patch size, shape and perforation on threshold habitat availability, and with total patch amount can inform design and/or evaluation of conservation, restoration or enhancement options for focal taxa or biodiversity in general.

Temporally robust occupancy frequency distributions in riverine metacommunities explained by local biodiversity regulation

AbstractAimThe mechanisms determining the distribution of the number of sites species occupy, the occupancy frequency distribution (OFD), remain incompletely understood despite decades of research. To explore the dominant mechanisms responsible for the shape and temporal dynamics of empirical OFD, we develop a simple patch occupancy framework with intrinsically regulated local richness and fit the model to a highly replicated dataset describing macroinvertebrate, macrophyte and diatom occupancy.LocationEngland.Time periodUp to years between 1990 and 2020.Major taxa studiedMacroinvertebrates, macrophytes and diatoms.MethodsWe study the OFD in a highly replicated dataset of freshwater metacommunities in England across time. We consider temporal change in species richness, composition, and in the shape of the OFD. Goodness‐of‐fit of the steady state of a simple patch occupancy model—which predicts a log‐series OFD—to the empirical observations is assessed. Additionally, we test the capacity of the model to predict metacommunity‐scale processes.ResultsOur model provides a consistently good fit to empirical OFDs. It can additionally be used to predict metacommunity‐scale species turnover.Main conclusionsOur results support the view that metacommunity structure reflects a dynamic steady state controlled by local limits to coexistence.

Stepping stones to extirpation: Puma patch occupancy thresholds in an urban-wildland matrix.

Habitat loss and fragmentation are the leading causes of species range contraction and extirpation, worldwide. Factors that predict sensitivity to fragmentation include high trophic level, large body size, and extensive spatial requirements. Pumas (Puma concolor) exemplify these qualities, making them particularly susceptible to fragmentation and subsequent reductions in demographic connectivity. The chaparral-dominated ecosystems surrounding the greater San Francisco Bay Area encompass over 10,000 km2 of suitable puma habitat, but inland waterways, croplands, urban land uses, and extensive transportation infrastructure have resulted in widespread habitat fragmentation. Pumas in this region now exist as a metapopulation marked by loss of genetic diversity, collisions with vehicles, and extensive human-puma conflict. Given these trends, we conducted a photo survey from 2017 to 2021 across 19 patches of predicted habitat and compiled a dataset of >6584 puma images. We used a logistic regression analytical framework to evaluate the hypothesis that puma patch occupancy would exhibit a threshold response explained by patch size, isolation, and habitat quality. Contrary to predictions, only variables related to patch size demonstrated any power to explain occupancy. On average, occupied patches were 18× larger than those where they were not detected (825 ± 1238 vs. 46 ± 101 km2). Although we observed pumas in patches as small as 1 km2, logistic regression models indicated a threshold occupancy probability between 300 and 400 km2, which is remarkably close to the mean male puma home range size in coastal California (~381 km2). Puma populations dependent on habitats below this value may be susceptible to inbreeding depression and human-wildlife conflict, and therefore vulnerable to extirpation. For species conservation, we suggest conflicts might be ameliorated by identifying the largest, isolated patches for public education campaigns with respect to management of domestic animals, and remaining connective parcels be identified, mapped, and prioritized for targeted mitigation.

Exploring Less Invasive Visual Surveys to Assess the Spatial Distribution of Endangered Mediterranean Trout Population in a Small Intermittent Stream.

Monitoring the conservation status of endangered freshwater fish using less invasive methods poses challenges for ecologists and conservationists. Visual surveys have been proposed as an alternative to electrofishing, which is a standard methodology that can cause injuries, physiological stress and post-release mortality in organisms. To test the efficacy of visual methods, a study was conducted in an intermittent stream of Sardinia (Italy). Two visual methods were employed: a visual survey from streambanks (VSS) and an underwater visual survey (UVS) using cameras. The aims of this study were (1) to compare the effectiveness of these methods in detecting patch occupancy patterns and (2) to investigate the effect of environmental variables on the detection probability of Mediterranean native trout. Environmental variables characterizing pool habitats were recorded, and generalized linear models (GLMs) were employed to assess the correlation between these variables and trout presence/absence. GLM analysis revealed that UVS had higher detection probability with larger pool volume, whereas submerged macrophytes negatively affected detection probability. Detection from streambanks (VVS) was negatively affected by a high turbulence rate. In conclusion, our study suggests the utility of visual methods to describe patterns of patch occupancy of Mediterranean trout. However, methods can be differently affected by environmental variables. Therefore, monitoring programs using these methods should consider these factors to ensure a reliable description of within-stream trout distribution in intermittent streams.

An investigation of patch occupancy and dispersal by third to final instar nymphs of Brachytrupes megacephalus Lefèbvre, 1827 (Orthoptera: Gryllidae: Gryllinae) across the sand dune biotope at the Għadira Nature Reserve, Malta.

Dispersal patterns of third, fourth and fifth instar nymphs of the stenoecious gryllid, Brachytrupes megacephalus (Lefèbvre, 1827), are investigated on the sand dune within the Għadira Nature Reserve, a remnant habitat patch forming part of the core area that supports the largest population of the species in Malta. Field investigations were carried out over a period of 11 weeks during a specific 75 minute time window, when nymphs are known to engage in subaerial activity at the mouth of their respective burrow. Climatic variables are examined in relation to abundance, while dispersal patterns are presented. The study shows that the predominant movement of nymphs across the terrain is northward, mainly to the northwest and the north-northeast. The present contribution also provides a summary of recommendations for conservation of the species, including an interdisciplinary approach to habitat management at multiple spatial scales.

Combining expert knowledge of a threatened trout distribution with sparse occupancy data for climate‐related projection

AbstractObjectiveTo evaluate the vulnerability of Bull Trout Salvelinus confluentus to potential climate changes across its range in Oregon, we compiled disparate expert knowledge of the distribution of spawning and rearing and combined these probabilistic statements as data along with documented records of breeding and rearing in a joint occupancy model.MethodsThe joint expert knowledge–occupancy model, which was based on discrete patches of cold water (≤13°C) suitable for spawning and rearing, permitted the association of true occupancy with climate and other explanatory variables while accounting for variation in detection probability. We then applied estimated relationships of patch occupancy with explanatory variables to projected coldwater patch configurations in the years 2040 and 2080.ResultProjections of the kilometers of occupied coldwater patch in future decades suggest precipitous declines if current relationships of occupancy with environmental variables are maintained. Impacts of climate changes in future decades manifest directly through the outright loss of coldwater patches and increases in winter high flows but also indirectly by increased isolation.ConclusionCombining probabilistic statements of species distributions from knowledgeable experts with sparse occupancy data may be a robust and timely alternative when large numbers of repeated occupancy surveys are infeasible.

Population Estimates of the Endangered Javan Hawk-Eagle Based on Habitat Distribution Modeling and Patch Occupancy Surveys

ABSTRACT Estimating the population size of threatened species is problematic and has biases because of a lack of validation data. The Javan Hawk-Eagle (Nisaetus bartelsi) is an endangered raptor endemic to the remnants of natural rainforests of Java, Indonesia. We aimed to improve the accuracy of population estimates through a combination of current habitat distribution modeling and patch occupancy surveys. Higher-resolution data sources (improved from 250 m to 30 m) were used in a predicted probability model using logistic regression. Patch occupancy surveys were conducted in habitat patches identified from a predictive analysis and field validation results after 2008. We estimated population sizes only in occupied patches ≥20 km2 (size based on Javan Hawk-Eagle home-range size). The area of suitable habitats currently totaled 10,804 km2, as calculated from the results of the 2019 predicted probability model (9106 km2) and field validation (1698 km2). The predicted area in 2019 decreased by 6.5% (638 km2) from that in 2008. We detected small suitable patches because of improvements in data resolution. The patch occupancy survey validated 44 of the 74 patches (59.5%) in the current habitat distribution. We confirmed that 38 patches (10,166 km2) were occupied by Javan Hawk-Eagles, and we estimated the population to be 511 ± 3.1 (SE) pairs. This apparent population increase is attributable to improved methodologies in predicting habitat distribution and estimating population size.

Landscape‐scale dynamics of a threatened species respond to local‐scale conservation management

Landscape‐scale approaches are increasingly advocated for species conservation but ensuring landscape level persistence by enlarging the size of patches or increasing their physical connectivity is often impractical. Here, we test how such barriers can be overcome by management of habitat at the local (site‐based) level, using a rare butterfly as an exemplar. We used four surveys of the entire UK distribution of the Lulworth skipper Thymelicus acteon over 40 years to test how local habitat influences population density and colonization/extinction dynamics, and parameterized, validated and applied a metapopulation model to simulate effects of varying local habitat quality on regional persistence. We found the total number of populations in four distribution snapshots between 1978 and 2017 varied between 59 and 84, and from 1997 to 2017 34% of local populations showed turnover (colonization or extinction). Population density was closely linked to vegetation characteristics indicative of management, namely height and food plant frequency, both of which changed through time. Simulating effects of habitat quality on metapopulation dynamics 40 years into the future suggests coordinated changes to two key components of quality (vegetation height and food plant frequency) would increase patch occupancy above the range observed in the past 40 years (50–80%). In contrast, deterioration of either component below threshold levels leads to metapopulation retraction to core sub‐networks of patches, or eventual extirpation. Our results indicate that changes to habitat quality can overcome constraints imposed by habitat patch area and spatial location on relative rates of colonization and local extinction, demonstrating the sensitivity of regional dynamics to targeted in situ management. Local habitat management therefore plays a key role in landscape‐scale conservation. Monitoring of population density, and the monitoring and management of local (site‐level) habitat quality, therefore represent effective and important components of conservation strategies in fragmented landscapes.

Multi-resolution habitat models of the Puerto Rican Nightjar Antrostromus noctitherus

Summary The Puerto Rican Nightjar Antrostomus noctitherus is an endemic Caprimulgid found in dry coastal and lower montane forests of south-western Puerto Rico. Information on the species (e.g. abundance, nesting biology) has been mostly restricted to forest reserves (i.e. Guánica Forest and Susúa Forest) with limited information available from private lands. We collected stand-level vegetation structure and geographical information from forest reserves and private lands to model habitat suitability and distribution for the Nightjar. Results of the stand-level model indicated forest type and midstorey vegetation density best predicted Nightjar habitat. Our spatial model predicted considerably more Nightjar habitat (17,819.64 ha) located outside protected areas than previously reported. Further, the model highlighted several localities of importance for the species across southern Puerto Rico, all located within private lands. We used a patch occupancy approach to assess regions identified by the landscape-level model as suitable for the Nightjar and documented the presence of the species in 32 of 55 sites, located in 12 of 18 municipalities across southern Puerto Rico. The protection and restoration of forest across the southern coast of Puerto Rico would help to ensure the long-term persistence of the Nightjar across a considerable portion of its range. Addressing habitat needs may be the single most effective mechanism to achieve recovery of the species.

Survey of the amphibians in “Fânațele Clujului – Copârșaie”, part of the “Dealurile Clujului de Est” (ROSCI0295) Natura 2000 protected area

"As habitat loss poses challenge to conservation, it is becoming increasingly important to address questions about the extent to which connectivity between habitat patches is changing, and how this affects the local population of different species in these patches. The objective of our research was to monitor ponds and the pond-breeding amphibian species in a protected area. Therefore, we conducted day and night surveys, and compare the data collected in 2022 with the results of the latest available survey (2019), to simulate the patch occupancy of amphibian species over a 25-year timeframe. We found that combining the species occupancy data collected from both day and night surveys lead to higher patch occupancy values and higher number of registered individuals, compared to data collected only during daytime. The number of ponds decreased from 2019 to 2022, and further habitat loss could result in the disappearance of the local population if the area continues to dry out. Climate and landscape change could be major contributors to habitat loss in the future, therefore, in order to ensure the persistence of these local populations, we recommend the development of climate and habitat scenarios, and the planning of conservation measures based on these scenarios. Keywords: amphibian conservation, Transylvanian Plain, SPOM"

Stress-associated metabolites vary with both season and habitat across populations of a climate sentinel species

ABSTRACT Relating physiological stress to habitat quality could refine conservation efforts. Habitat quality, which is often inferred from patch occupancy or demographic rates, might be measured in a more timely and nuanced way using metrics of physiological stress. To understand whether stress-associated hormones vary with metrics of habitat quality, we measured fecal glucocorticoid metabolite (FGM) levels in the American pika (Ochotona princeps), a small mammal with well-defined habitat (talus), which can vary in quality depending on the presence of subsurface ice features. In spring and fall 2018, we collected feces noninvasively from pika territories in taluses “with” or “without” subsurface ice to capture seasonal variation in FGM between habitat types. We used linear mixed effects models to explore the interactions among season, habitat metrics (including subsurface ice status), and subsurface temperature as predictors of FGM. We found support for interacting effects on FGM levels, which covaried with season, elevation, putative ice presence, graminoid to forb ratio, graminoid cover, and measures of acute subsurface heat exposure. However, only one subsurface temperature metric differed according to putative presence of subsurface ice. Our results contribute to the growing evidence that FGMs might be developed as a tool to assess habitat quality.

Appearance of a population of the mangrove rail Rallus longirostris (Rallidae) in salt marshes invaded by the exotic tanner grass Urochloa arrecta (Poaceae) and its disappearance after plant management.

The online version contains supplementary material available at 10.1007/s13157-022-01642-7.