ABSTRACT The effects of unpaved roads on local wildlife vary across taxa and ecological contexts, making synthesis of broad patterns difficult. For small ectotherms, vegetation gaps created by unpaved roads modify the local environment in such a way that these features may be more suitable than more naturalized landscapes. We quantified how unpaved roads in Ocala National Forest (Florida, USA) affect relative abundance and microhabitat associations of three lizard species: Florida scrub lizards ( Sceloporus woodi ), six‐lined racerunners ( Aspidoscelis sexlineatus ), and green anoles ( Anolis carolinensis ). We explored how these traits differ between unpaved roads and adjacent stand interiors in two habitat types: sand pine scrub and longleaf pine sandhill. Regardless of habitat type, the relative abundance of Florida scrub lizards was greater along unpaved roads than in stand interiors. However, six‐lined racerunner and green anole relative abundance showed no association with unpaved roads. Regardless of species or habitat type, lizards found near roads were encountered more on leaf litter than those in stand interiors, yet substrate temperature associations were unaffected by unpaved roads. Ultimately, these results support the potential for unpaved roads to affect species abundance and microhabitat associations at fine spatial scales.

PremiseFire is a key ecological process that shapes ecosystems globally, yet fire adaptation strategies remain unclear for many species, especially for ground lichens that are reliant on pyrogenic landscapes but are evidently fire‐intolerant. In the pyrogenic Florida scrub, fire‐sensitive Cladonia ground lichen species are an important component of the ground layer and influence ecosystem processes. The endangered Cladonia perforata is of special concern because fire regimes can dictate the persistence of the species. We aim to clarify (1) its subpopulation trends, (2) its post‐fire recovery, and (3) the influence of microhabitat factors on these patterns.MethodsWe analyzed 14 years of detailed monitoring data from nine Cladonia perforata subpopulations on the Lake Wales Ridge that experienced eight fires. We used subpopulation area, occupancy, and fine‐scale cover to estimate abundance on multiple spatial scales and analyzed the effects of burn severity, dominant ground cover, and canopy cover on C. perforata abundance over time.ResultsAbundance declined across almost all subpopulations (decreased odds ratio 0.14 for occupancy and 0.20 for cover per year). Severe fire reduced abundance, and subpopulations did not recover. Abundance was highest in litter cover, with a preference for open canopy post‐fire.ConclusionsCladonia perforata is a fire‐sensitive species with very limited growth and recolonization capacity. The detrimental fire effects here indicate a fire avoidance strategy, but litter accumulation may limit this strategy. These results highlight the delicate balance of using fire to promote the conservation of fire‐sensitive species in a pyrogenic habitat.

Environmental Stress Shifts Growth Strategies of Oak and Heath Shrubs in the Florida Scrub

Extensive research has focused on effects of non‐breeding helpers on the reproductive success of cooperatively breeding birds, yet in the cooperatively breeding Florida Scrub Jay Aphelocoma coerulescens about half of breeding pairs do not have helpers in any given year. We tested for effects of breeder experience and environmental variables (acorn abundance, fire history and territory size) on reproductive output of breeding pairs that lacked helpers. In generalized linear mixed models, explanatory variables that best explained variation in reproductive output included female breeder experience, time since fire, territory size and acorn crop. Our results emphasize that active habitat management through prescribed fire enhances the reproductive success of this declining bird across a diversity of social group compositions.

PremiseAmphistomy, the presence of stomata on both leaf surfaces, can increase photosynthesis yet is uncommon across vascular plants. The relative infrequency of amphistomy is often attributed to high costs, such as transpirational water loss. The Florida scrub—a hot, dry, shrub‐dominated habitat—historically has experienced frequent fire, yet decades of anthropogenic suppression coupled with the reintroduction of prescribed burns has led to varied fire regimes. In this study, we investigated the links between amphistomy and fire with regard to the presence of the trait across species in this pyrogenic habitat and within‐species variation before and after experimental fire and across a time‐since‐fire gradient (0.25–50 years).MethodsWe surveyed the presence of amphistomy for 116 plant species across scrub habitats and experimentally investigated intraspecific variation in stomatal traits for two amphistomatous, post‐fire resprouting species of palmetto, Serenoa repens and Sabal etonia (Arecaceae).ResultsAmphistomy was present in 62.9% of all surveyed species and 85.7% of post‐fire obligate reseeders, suggesting amphistomy may be particularly beneficial in this group and broadly in the Florida scrub conditions. The stomatal ratio (upper/total stomatal density) was generally stable within and across individuals of both species after fire. Stomatal density decreased following fire in S. etonia, with both species experiencing high variation in the post‐fire years.ConclusionsAmphistomy is common in the Florida scrub and relatively stable within species in response to fire, while stomatal density responds plastically during post‐fire recovery.

Survey of Lichen Diversity and Abundance in a Florida Scrub in Relation to Various Temporal Stages of Burn Recovery

Abstract The Endangered Species Act aims to recover imperiled species to the point of delisting; however, few plant species have been delisted due to recovery. Critical to many species' recovery criteria are introductions, yet the long‐term success of plant introductions is highly variable and their use in delisting decisions is relatively untested. In this study, we examined the dynamics of eight introduced populations of the recently delisted Chrysopsis floridana (Florida Golden Aster), a fire‐dependent perennial plant endemic to Florida scrub habitats. We analyzed 6 years of demographic data (2017–2022) and 10 years of prescribed fire records to assess population trends, fire management effects, and vital rates related to recruitment, survival, and reproduction. Our results show that population densities with regular fire management increased, while unburned populations generally declined. Prescribed fire increased seedling recruitment and survival rates. We estimated a fire‐return interval of approximately 5 years is needed for population persistence, shorter than the 10‐year interval used in the delisting decision. Our findings suggest that post‐delisting monitoring should prioritize fire management to ensure the long‐term success of introduced populations. Our work highlights the need for more robust, specific delisting criteria, particularly regarding the role of introductions, long‐term monitoring, and post‐introduction habitat management. These insights can inform future recovery plans for fire‐dependent species and improve the delisting process for plants under the Endangered Species Act.

Abstract Managers often use mechanical disturbance in conjunction with, or in place of, prescribed fire to maintain pyrogenic plant communities in the southeastern United States. However, information on the effects of mechanical fire-surrogates on disturbance-dependent wildlife is lacking. The Florida scrub-jay Aphelocoma coerulescens is an endemic bird species reliant on Florida scrub, a pyrogenic shrubland plant community narrowly distributed on sandy ridges in peninsular Florida. Ocala National Forest in north central Florida supports the largest remaining population of Florida scrub-jays, and historically, maintenance of most scrub habitat at the site is through the commercial harvest (clearcutting) of mature sand pines Pinus clausa. Recently, a habitat restoration program established Scrub-Jay Management Areas by converting clearcut stands to scrub maintained in an early-successional condition by prescribed fire. We studied Florida scrub-jays in Scrub-Jay Management Areas (2016–2023) to better understand how family-group density changed over time since fire management compared with time since harvest in clearcut stands. In scrub treated with prescribed fire, Florida scrub-jay family-group density increased more rapidly postdisturbance and was consistently higher than in clearcut stands. Based on model predictions, the maximum mean density of family groups occurred at 8.5 y postfire (11.8 family groups/41 ha) in Scrub-Jay Management Areas and 6.2 y postharvest (5.5 family groups/41 ha) in clearcut stands. Our study provides the first quantitative data on the response of Florida scrub-jay populations to new forest management practices in this large and critically important population. These data provide an essential component for developing population models for Ocala National Forest under current conditions and for modeling the potential effects of future management decisions.

Pollinator gardening has gained momentum with an increased consumer interest in selecting native rather than non-native plant species to reduce water dependence and maximize the biodiversity value in both public greenspaces and residential gardens. Native plant species can enhance biological control and benefit ecosystems and wildlife. Often, they are also better-adapted to local environmental conditions, including temperature and rainfall, thus increasing their survival and reducing associated maintenance costs, primarily by requiring less water. Commercially available pollinator-friendly plant mixes often include both native and non-native species. A 2-year study was conducted to determine the main effects of plant provenance (native or non-native) and irrigation (full or partial irrigation) on landscape performance and flowering of 20 plants, including 10 congeneric pairs of native and non-native taxa that were planted in two locations (north and northcentral Florida). Native and non-native taxa were paired by genus to analyze the effect of the plant native status on vegetative and floral traits while controlling for variations in leaf and floral morphologies, growth habits, and blooming periods, which was a key and novel component of our study design. Represented native species included Spanish needles (Bidens alba), false rosemary (Conradina grandiflora), tickseed coreopsis (Coreopsis leavenworthii), blanket-flower (Gaillardia pulchella), swamp rosemallow (Hibiscus grandiflorus), inkberry (Ilex glabra), spotted beebalm (Monarda punctata), azure blue sage (Salvia azurea), Florida scrub skullcap (Scutellaria arenicola), and Walter's viburnum (Viburnum obovatum). Non-native taxa paired with native congeners included Beedance® painted red bidens (Bidens ferulifolia) or Goldilocks Rocks® bidens (Bidens ferulifolia ‘BID 16101’), barbeque rosemary (Salvia rosmarinus ‘Barbeque’), Jethro Tull coreopsis (Coreopsis × ‘Jethro Tull’), Arizona sun blanket-flower (Gaillardia ×grandiflora ‘Arizona Sun’), Ruffled Satin® rose of Sharon (Hibiscus syriacus ‘SHIMCR1’), dwarf Burford holly (Ilex cornuta ‘Dwarf Burford’), pardon my pink beebalm (Monarda didyma ‘Pardon My Pink’), big blue salvia (Salvia longispicata × S. farinacea ‘PAS1246577’), Malaysian skullcap (Scutellaria javanica), and Sandankwa viburnum (Viburnum suspensum). Overall, the results revealed that native plants outperformed non-native plants and exhibited greater survival, more vegetative growth, and greater floral abundance regardless of the irrigation treatment. Although there was no overall effect of irrigation on plant size or flower abundance, there were some species-specific responses, especially during the establishment year, and plants under full irrigation had greater survival in the establishment year. Thus, in general, the effects of plant provenance were stronger and more consistent across years than irrigation. Additional studies are underway to determine the floral rewards of these species and their attraction to diverse pollinators.

Ectoparasite load generates habitat-specific variation in colour badge intensity and badge size in male lizards

ABSTRACT Habitat heterogeneity is a key driver of biodiversity of macroorganisms, yet how heterogeneity structures belowground microbial communities is not well understood. Importantly, belowground microbial communities may respond to any number of abiotic, biotic, and spatial drivers found in heterogeneous environments. Here, we examine potential drivers of prokaryotic and fungal communities in soils across the heterogenous landscape of the imperiled Florida scrub, a pyrogenic ecosystem where slight differences in elevation lead to large changes in water and nutrient availability and vegetation composition. We employ a comprehensive, large-scale sampling design to characterize the communities of prokaryotes and fungi associated with three habitat types and two soil depths (crust and subterranean) to evaluate (i) differences in microbial communities across these heterogeneous habitats, (ii) the relative roles of abiotic, biotic, and spatial drivers in shaping community structure, and (iii) the distribution of fungal guilds across these habitats. We sequenced soils from 40 complete replicates of habitat × soil depth combinations and sequenced the prokaryotic 16S and fungal internal transcribed spacer (ITS) regions using Illumina MiSeq. Habitat heterogeneity generated distinct communities of soil prokaryotes and fungi. Spatial distance played a role in structuring crust communities, whereas subterranean microbial communities were primarily structured by the shrub community, whose roots they presumably interacted with. This result helps to explain the unexpected transition we observed between arbuscular mycorrhiza–dominated soils at low-elevation habitats to ectomycorrhiza-dominated soils at high-elevation habitats. Our results challenge previous notions of environmental determinism of microbial communities and generate new hypotheses regarding symbiotic relationships across heterogeneous environments.

Life span varies greatly across plants, with some species being capable of extreme longevity. Yet even long-lived individuals are susceptible to climatic events, fire, and other challenges. We examined rare mortality events and their causes in two long-lived palmettos over four decades. We monitored the survival of the clonal Serenoa repens and non-clonal, Florida-endemic Sabal etonia from 1981 to 2022 in four habitats along an elevational gradient within the globally imperiled Florida scrub ecosystem. We considered several challenges to palmetto survival, including extreme fires, shading due to lack of fire, droughts, periods of high precipitation, and possible pathogens. Survival of palmettos was remarkably high, and mortality was infrequent (Serenoa: cumulative, 5.7%; annualized, 0%-0.68%; Sabal: cumulative, 3.5%; annualized, 0%-0.43%). Mortality was highest in higher-elevation habitats with greater soil drainage, and smaller palmettos were more likely to die. When subjected to extreme fire, Serenoa suffered greater mortality than Sabal. Mortality in long-unburned habitats with increased shading rivaled that which occurred with extreme fire. There was no evidence of mortality due to lethal bronzing palm disease. Both palmettos had exceptionally low mortality rates, which, coupled with earlier work showing slow rates of transition from seedling to adult and remarkable adult longevity, suggest notably low rates of population turnover. Observed mortality in long-unburned habitats suggests the importance of fire-management planning with prescription burning. Lengthy age to reproduction and/or dependency on clonal propagation limits migration or genetic adaptation to altered conditions caused by climate change.

Abstract By allowing for increased absorption or reflectance of solar radiation, changes in pigmentation may assist ectotherms in responding to immune challenges by enabling a more precise regulation of behavioral fever or hypothermia. Variation in epigenetic characteristics may also assist in regulating immune-induced pigmentation changes and managing the body's energetic reserves following infection. Here, we explore how dorsal pigmentation, metabolic rate, and DNA methylation in the Florida scrub lizard (Sceloporus woodi) respond to two levels of immune challenge across two habitat types. We found changes in pigmentation that are suggestive of efforts to assist in behavioral fever and hypothermia depending on the intensity of immune challenge. We also found correlations between DNA methylation in liver tissue and pigmentation change along the dorsum, indicating that color transitions may be part of a multifaceted immune response across tissue types. The relationship between immune response and metabolic rate supports the idea that energetic reserves may be conserved for the costs associated with behavioral fever when immune challenge is low and the immune functions when immune challenge is high. While immune response appeared to be unaffected by habitat type, we found differences in metabolic activity between habitats, suggesting differences in the energetic costs associated with each. To our knowledge, these results present the first potential evidence of pigmentation change in ectotherms in association with immune response. The relationship between immune response, DNA methylation, and pigmentation change also highlights the importance of epigenetic mechanisms in organism physiology.

Intermittent locomotion is a common locomotor mode in small vertebrates. Pausing is thought to aid in locating a predator or prey, enhancing crypsis, lowering energy costs, and/or maneuvering around obstacles or toward a refuge. Many lizards flee predators by turning into potential refugia and subsequently pausing, presumably to conceal themselves. Intermittent locomotion may be associated with turning by allowing an animal time to assess its surroundings and/or decreasing the likelihood of losing its footing. In this study, we quantify locomotor performance and the use of intermittent locomotion in Florida scrub lizards (Sceloporus woodi) when navigating either a 45° or 90° turn. Lizards paused in 92.91% of all trials, and yet despite pausing, instantaneous speed was not different entering or exiting the turn. This result suggests that turning comes at minimal cost to forward speed for lizards under these conditions. Pausing during a turn, however, did slow speed in the turn. Interestingly, the speed in the turn did not differ in trials with a pause before the turn versus trials without a pause. The angle of the turn also had no effect on whether lizards paused. We found that lizards increase peak acceleration following pauses to compensate for lost speed during the pause, providing a mechanism that may minimize negative fitness effects associated with slow running speeds and allow intermittent locomotion to be such a common strategy in lizards.

Thirty years after its designation as a federally endangered species, the Florida Perforate Cladonia (FPC) remains imperiled in isolated populations in the Florida scrub in the southeastern USA. For threatened and endangered species, such as FPC, reference genomes provide critical insight into genomic diversity, local adaptations, landscape-level genetics, and phylogenomics. Using high-throughput sequencing, we assemble the first draft nuclear and mitochondrial genomes for the FPC mycobiont-Cladonia perforata. We also assess genetic diversity within and among populations in southeastern Florida using genome-scale data and investigate diversity across the entire nuclear ribosomal cistron, including the standard DNA barcoding marker for fungi. The draft nuclear genome spanned 33.6 Mb, and the complete, circular mitochondrial genome was 59 Kb. We also generated the first chloroplast genome, to our knowledge, for the photobiont genus associated with FPC, an undescribed Asterochloris species. We inferred the presence of multiple, distinct mycobiont parental genotypes (genets) occurring at local scales in southeastern Florida, and strikingly, no genets were shared among even the closest sample sites. All sampled thalli shared identical mitochondrial genomes, while the nuclear ribosomal cistron showed limited variability-highlighting the genetic resolution provided by nuclear genome-scale datasets. The genomic resources generated here provide critical resources for informed conservation efforts for the FPC.

Simple SummarySentinels monitor their surroundings from vantage points for early detection of predators and rivals. The presence of multiple sentinels in a group may allow sentinels to relax their vigilance, especially if sentinels monitor different areas at the same time. We investigated sentinel behavior in groups of the Florida scrub jay (Aphelocoma caerulescens). Sentinels in this species turn their heads frequently to monitor different areas for potential threats. As predicted, we found that sentinels turned their heads less frequently in the presence of other sentinels. However, multiple sentinels tended to gaze in the same direction at the same time more often than predicted by chance alone. Gaze synchronization reduces the efficiency of collective detection by increasing the amount of time that some areas are not monitored by any sentinel. Despite the benefits of the presence of other sentinels, our results highlight the limits to collective detection when multiple individuals are vigilant at the same time.Sentinels can detect predators and rivals early by monitoring their surroundings from vantage points. Multiple sentinels in a group may reduce the perceived predation risk by diluting the risk and increasing collective detection, especially if sentinels monitor different areas at the same time. We investigated sentinel behavior in groups of the Florida scrub jay (Aphelocoma caerulescens). Sentinels in this species turn their heads frequently to monitor different areas for threats. As predicted, we found that sentinels turned their heads less frequently in the presence of other sentinels. Multiple sentinels, however, tended to gaze in the same direction at the same time more often than predicted by chance alone. Gaze synchronization reduces the efficiency of collective detection by reducing visual coverage at any one time at the group level. Despite the benefits of the presence of other sentinels, our results highlight the limits to collective detection when multiple individuals are vigilant at the same time.

Abstract Species translocations are increasingly common in rare plant conservation. Wild populations can provide basic ecological knowledge to improve their chance of success. In the heavily fragmented Florida scrub, USA, many listed species require translocations to persist, including Dicerandra christmanii. In 1994, we began monitoring the only protected population of D. christmanii growing both in gaps (open areas) within the shrub matrix and on roadsides. In 2010, we augmented this population by adding plants and seeds to unoccupied gaps. In 2012, we introduced plants to a separate protected site to create a new population. We evaluated early translocation success using generalized linear mixed‐effect models of vital rate variation among habitat types. Survival probability increased with size, peaking at 0.6–0.8, and was lowest in augmentations and highest in introductions. Growth increased with plant size across all habitat types, except for the largest adults which experienced senescence. Naturally recruited plants in gaps showed the highest reproduction probability and fecundity at smaller sizes, but larger plants in translocations had the highest fecundity. Yearling recruitment was higher in translocated plants relative to naturally recruited plants in gaps during the initial years following outplanting. Experimental components of translocations also affected outplanting performance with positive effects of fire. These analyses suggest a high potential for translocations to become established and contribute to species recovery.

El efecto influyente del fuego sobre la formación de la vegetación de matorral de la Florida está bien documentado; sin embargo, se sabe relativamente poco sobre el papel del fuego en las interacciones tróficas, como las que se dan entre plantas y herbívoros. Aquí, examinamos la respuesta de herbivoría de los insectos al tiempo transcurrido desde el incendio y la sucesión en Lyonia fruticosa (Michx.) G.S. Torr. (Ericaceae), un arbusto ericáceo que se encuentra en los matorrales del centro-sur de la Florida. Medimos la herbivoría en > 200 plantas a lo largo de un gradiente de tiempo desde el incendio de 7 sitios (que van de 0,6 a 8,7 años) mediante (1) el estudio de las hojas recientemente enrojecidas durante 3 meses para controlar la edad de las hojas, y (2) el estudio de la herbivoría en todo el territorio. plantas enteras independientemente de la edad de la hoja. También registramos los tipos de daño (masticación, raspado y minería) para determinar si los grupos de herbívoros se vieron afectados por el tiempo transcurrido desde el incendio. Usando modelos aditivos generalizados, encontramos que la herbivoría aumentó durante 5 a 6 años después del incendio con un 59,8 % de la desviación explicada por el tiempo transcurrido desde el incendio en estudios de hojas enrojecidas y un 76,6 % en estudios de toda la planta. La masticación fue el tipo de daño dominante y aumentó durante 5 años después del incendio. Los daños por raspado y minería fueron menos frecuentes y no se vieron afectados por el tiempo transcurrido desde el incendio dentro del rango estudiado. Además, modelamos las respuestas posteriores al incendio de los rasgos de L. fruticosa (altura, tallos, floración y área foliar) y descubrimos que ocurrieron cambios en el crecimiento y la reproducción dentro de los primeros 4 a 6 años posteriores al incendio. Los niveles de herbivoría aumentaron a medida que las plantas se recuperaron y alcanzaron su punto máximo en los años 5 y 6 posteriores al incendio, lo que indica que los insectos herbívoros, como las plantas, están bien adaptados a la dinamica pirogénica del territorio.

Fire shapes habitats and therefore influences the genetic characteristics of populations. Florida scrub is a fire-dependent habitat with several precinctive species, including Florida Scrub Lizards (Sceloporus woodi). Fire history of scrub patches could affect the movement patterns of Florida Scrub Lizards, thereby altering the genetic characteristics of local populations. We characterized the effect of time since fire (TSF) on genetic diversity and differentiation at 6 microsatellite loci in the Florida Scrub Lizard (n = 413) collected from 17 sites in Highlands County, Florida. Private allelic richness was positively correlated with TSF (r = 0.56, P = 0.009). In sites with a TSF of 3–17 yr, TSF was negatively correlated with expected heterozygosity (r = -0.90, P = 0.009), inbreeding (r = -0.77, P = 0.04), allelic richness (r = -0.79, P = 0.03), and private allelic richness (r = -0.80, P = 0.03); TSF was positively correlated with mean pairwise relatedness (r = 0.85, P = 0.02). Therefore, a consequence of TSF is short-term change to local population genetics that is likely precipitated by responses of Florida Scrub Lizards to habitat modification. At a TSF of >20 yr, TSF and genetic diversity were not correlated, indicating that factors other than fire shape genetic diversity in long-unburned locations. We detected genetic differentiation using Bayesian clustering and estimates of F-statistics. Our results highlight the importance of consistent fire regimes in the Florida scrub on the genetic diversity of Florida Scrub Lizards. The presence of Florida Scrub Lizard populations in long-unburned sites, however, warrants further investigation.

Fire severity effects on the herpetofaunal diversity of the Florida scrub, a biodiversity hotspot