Geology topics

Research about Florida

Source-linked reports with geographic coverage including Florida.

At least 19 recordsLinked to original sources

USGS2026

Vessel avoidance behavior in green turtles off the west coast of Florida

Vessel strikes are an increasing source of mortality for sea turtles in coastal waters with high recreational vessel traffic. We quantified flight initiation distance (FID) and avoidance behavior of green turtles Chelonia mydas in response to an approaching vessel traveling at different speeds in shallow coastal waters of Florida. Observational boat surveys were conducted at 3 vessel speeds, and observed FID was evaluated in relation to vessel speed, turtle size class (<60 cm vs. ≥60 cm estimated carapace length), and environmental conditions using a regression tree analysis. Observed FID was most strongly partitioned by vessel speed, with shorter mean distances consistently associated with higher speeds. Mean observed FID ranged from approximately 7.7 m at low vessel speed under specific environmental conditions to approximately 5 m or less at higher speeds. Turtle size class was not associated with differences in observed FID. Flight behavior was non-random, with turtles most frequently fleeing directly away from the vessel’s trajectory, and was independent of vessel speed and turtle size. Observed FID reflects the combined effects of turtle behavior and observer detection. Nevertheless, the consistent association between higher vessel speed and reduced observed FID supports management strategies that would reduce boat speeds and increase boater awareness to protect green turtles in shallow coastal habitats.

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USGS2026

Predator hunting modes induce varied selection pressures on prey personality

Consistent individual differences in animal behavior—ie, personalities—have been documented in many taxa to have important fitness consequences in the context of predator-prey interactions. Multiple mechanisms have been suggested to maintain variation in prey personality traits, including life-history tradeoffs and divergent selection pressures from predators with different hunting strategies. However, empirical evidence for these hypotheses has been limited by a lack of data originating from complex multipredator systems in situ. To address this gap and evaluate these 2 mechanisms, we collected hispid cotton rats (Sigmodon hispidus) in the Florida Everglades and quantified 3 behavioral traits in the field. After releasing rats at their point of capture, we monitored their survival in their natural habitat where they faced threats from a diversity of ambush (snakes) and active predators (mammals; birds). Using Cox proportional hazards regression models and competing risks models, we assessed the effect of boldness, activity, and docility on rodent predation risk. Contrary to conventional predictions that bolder and more active individuals would face higher predation risk due to life-history tradeoffs, we found that the impact of these traits on prey survival varied with the predators' hunting modes: shyer, more active individuals were more likely to be killed by active predators, whereas less active rats appeared more likely to be killed by ambush predators. Our study supports the hypothesis that a diversity of predator hunting strategies may help maintain trait variation in prey populations.

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USGS2026

Repeated coral bleaching events have eroded reef accretion potential in the Florida Keys

Coral bleaching is now the primary driver of coral-reef degradation globally, threatening the persistence of coral-reef functions and the invaluable ecosystem services they support. The Florida Keys have been impacted by four severe, regional-scale coral-bleaching events, which occurred in 1997–1998, 2005, 2014–2015, and 2023. Our aim in this study was to quantify the effects of those thermal-stress events on the persistence of coral-reef structures. We leveraged long-term coral-reef monitoring data to quantify the impacts of coral bleaching on coral cover, carbonate production, and reef-accretion potential throughout the Florida Keys from 1996–2024. Our study indicates that coral bleaching drove significant declines of reef-building corals, which successively diminished regional-scale reef-accretion potential (from 1.65 ± 0.33 mm y -1 in 1996) and culminated with a regional-scale transition to net reef erosion (-0.12 ± 0.08 mm y -1 ) following the 2023 event. Coral bleaching was the primary driver of declining reef-building capacity, with the cumulative impacts of the four coral-bleaching events accounting for >75% of total declines since 1996. The 1997–1998 event alone drove ~50% of overall declines, largely due to losses of the shallow-water ecosystem engineer, Acropora palmata . More moderate impacts of thermal stress on regional reef-accretion potential in 2005 (6%) and 2014–2015 (9%) could lend some support to the hypothesis that the remaining corals were more thermally tolerant; however, the unprecedented thermal stress event in 2023 caused widespread coral-bleaching and bleaching-related mortality, and caused an additional 12% of the total decline in reef-accretion potential. Stony-coral tissue loss disease accounted for an additional 6% of the decline, with the remaining 19% unexplained. Coral bleaching has already dramatically reshaped the structure and function of coral reefs in the Florida Keys over the last three decades. With the high likelihood that thermal stress will accelerate moving forward, the persistence of Florida’s essential coral-reef functions and services is uncertain.

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USGS2026

3D Elevation Program—Florida

Using 3D Elevation Program data, a modern illustration of each State's landscape showcases its elevation differences in vivid detail. Each State has been consistently adjusted and colorized according to its highest and lowest elevations, accentuating differences even in States with low relief. To further emphasize landforms, shaded relief has been added on top of the elevation colors.

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USGS2026

Conflicts and collisions with an endangered carnivore: Landscape drivers and spatial risk pattern

Human–wildlife conflicts and anthropogenic mortality are expected to increase with the continuous encroachment on natural habitats within and around protected areas, yet the processes governing these risks remain poorly understood. We investigated the spatiotemporal dynamics and drivers of two distinct processes involving the endangered Florida panther ( Puma concolor coryi ; hereafter, panther): (1) direct human–panther interactions and livestock depredation (hereafter, conflicts), and (2) vehicle collisions (hereafter, collisions). Using long-term data collected between 2006 and 2022 within the panther's breeding range in Southwest Florida, USA, we applied dynamic occupancy models to estimate probabilities of occurrence, colonization, and extinction of conflicts and collisions while accounting for imperfect detection. A total of 277 conflicts and 239 collisions were recorded during the study period. Occurrence probabilities for both conflicts and collisions increased during the early years of the study and subsequently stabilized. Landscape configuration consistently showed strong associations with both processes. Conflicts were more likely in areas with fragmented but closely spaced habitat patches, whereas collisions were more likely along road segments characterized by connected landscapes with low resistance to panther movement. In contrast, areas that showed greater distances between habitat patches and increased proportions of protected area were associated with lower probabilities of conflict or collision persistence over time. A predictive map was created to highlight areas with high probability of conflict and road segments with high probability of collision in Southwest Florida, USA. Identifying areas with elevated risk can inform targeted mitigation strategies, including habitat management, wildlife crossings, and outreach efforts, and further support long-term coexistence between humans and large carnivore populations.

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USGS2026

Restoration is a partial but not complete solution for long-term declines in oyster populations—A case history from the northeastern Gulf of America

Objective We sought to evaluate whether oyster reef restoration is associated with sustained increases in intertidal eastern oyster Crassostrea virginica density in Suwannee Sound, Florida, and to examine how commercial fishing activity and freshwater discharge may modify those patterns. Methods We monitored intertidal oyster reefs for 14 years, including 9 years prior to large-scale restoration (completed in 2018) and 5 years of standardized postrestoration monitoring beginning in 2019 at Lone Cabbage Reef, an offshore intertidal reef complex that was rebuilt to target elevation using dolomite limestone. A Bayesian negative-binomial generalized linear mixed model framework estimated oyster densities while accounting for spatial differences among inshore, nearshore, and offshore reefs; variation in transect length; and temporal variability. We assessed restoration effectiveness via repeated-measures monitoring of fixed restored sites and landscape-scale comparisons of restored versus unrestored reefs. We evaluated covariates of management interest—commercial fishing activity and river discharge—using model comparison and posterior predictions of oyster density at observed covariate values. Results Restoration produced large per-area gains in live-oyster density on offshore reefs. At four fixed restored offshore stations, mean densities rose from near 0 to 91 oysters/m 2 (95% credible interval [CrI] = 43–185) within 6 months and reached 244 oysters/m 2 (95% CrI = 134–433) by year 5 at fixed restoration stations. At the broader landscape scale, restored offshore reefs averaged about 83 oysters/m 2 (95% CrI = 26–157) across sites and postrestoration periods, whereas model-based estimates for restored offshore reefs reached 218 oysters/m 2 (95% CrI = 128–366) in the final sampling period. Conclusions Restoring reef substrate rebuilt the physical capacity for oysters to persist and grow at Lone Cabbage Reef, yielding sustained density gains that degraded sites did not achieve on their own. Harvest status and river discharge showed weak, inconsistent associations once restoration was included, consistent with the interpretation that oyster cultch provides structural capacity, while environmental and fishing conditions modulate around it. Rebuilding and conserving oyster cultch constitute the essential first step to repair and sustain degraded oyster reefs; fishing regulations or favorable environmental conditions alone are unlikely to replace the need for reef structure.

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USGS2026

Petrography and mineralogy of selected pre-Middle Jurassic basement rocks beneath the Atlantic and Gulf Coastal Plains in Florida

Florida is covered by flat-lying sedimentary strata of the Atlantic and Gulf Coastal Plains. These strata have accumulated since Middle Jurassic time. The pre-Middle Jurassic, or basement, rocks that underlie the Coastal Plain in Florida are known only from drill cores and cuttings recovered from a relatively small number of boreholes. This data report presents petrographic observations and the results of X-ray diffraction analyses of basement rocks from 18 boreholes across Florida in support of the identification, discrimination, and correlation of units for a subcrop geologic map of pre-Middle Jurassic rocks composing Florida’s sub-Coastal Plain geology.

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USGS2026

Geologic map of pre-Middle Jurassic basement rocks beneath the Atlantic and Gulf Coastal Plains in Florida

Much of the southeastern United States, including all of Florida, is covered by flat-lying sedimentary strata of the Atlantic and Gulf Coastal Plains which have accumulated since Middle Jurassic time. The pre-Middle Jurassic rocks that underlie these coastal plains in Florida, here collectively referred to as “basement,” are known only from a relatively small number of boreholes. This scientific investigations map presents an interpretation of the basement geology in a 1:1,000,000-scale subsurface geologic map with supporting text, data, and figures. The subsurface mapping methodology integrates petrographic, geochronological, thermochronological, geochemical, and mineralogical analyses of drill cores and cuttings in the context of regional geophysical data. The pre-Middle Jurassic rocks of Florida consist of the Gondwanan (West African) Suwannee terrane which was accreted to Laurentia during the Alleghanian orogeny and subsequently intruded by Permian granites, superposed by early Mesozoic rift basins, and partially overlain by bimodal Jurassic volcanic rocks. The younger basement components, specifically the Southwest Florida volcanic province, North Florida tholeiites, early Mesozoic rift basins, and Alleghanian granitoids, have correlative and contemporaneous units throughout the Appalachian orogen. In contrast, Florida’s older basement rocks, including Paleozoic siliciclastic strata of the Suwannee basin, North Florida volcanic series, Osceola and Gaskin intrusive complexes, and the St. Lucie Metamorphic Complex, have neither surface exposures nor unequivocal correlates. Major structures include early Mesozoic normal faults and northwest-striking transfer zones such as the Jay fault. Many of these faults define the boundaries of subbasins within the South Georgia rift system. Top-of-basement structure contours show gentle arches and embayments that are also recognized in overlying coastal plain strata.

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USGS2026

Development of projected depth-duration-frequency curves for precipitation in Florida, 2020–59 and 2050–89

The planning, permitting, and design of stormwater-management projects require estimates of the depths of extreme precipitation for current and future events with specified durations and return periods. In this project, precipitation data from six downscaled climate datasets were used to determine changes in precipitation depth-duration-frequency curves from the period 1966–2005 to the periods 2020–59 and 2050–89. The downscaled climate datasets are from the Coupled Model Intercomparison Project Phases 5 and 6 and include (1) Coordinated Regional Downscaling Experiment (CORDEX), (2) Localized Constructed Analogs (LOCA), (3) Multivariate Adaptive Constructed Analogs (MACA), (4) Jupiter Intelligence Weather Research and Forecasting model (JupiterWRF), (5) LOCA version 2 (LOCA2), and (6) National Aeronautics and Space Administration Earth Exchange Global Daily Downscaled Projections (NEX-GDDP). Change factors—multiplicative changes in expected extreme precipitation magnitude from a historical to future period—were computed for grid cells containing National Oceanic and Atmospheric Administration Atlas 14 stations in Florida. Change factors for specific durations and return periods were developed to scale the National Oceanic and Atmospheric Administration Atlas 14 historical depth-duration-frequency values to the periods 2020–59 and 2050–89 on the basis of changes in extreme precipitation derived from six downscaled climate datasets. Overall, a large variation in change factors across downscaled climate datasets was found, with change factors generally being greater than 1 and increasing with return period. In general, median change factors were found to range within 1.01–1.58 for 2020–59 and 1.01–1.63 for 2050–89, depending on the downscaled climate dataset, region, duration, and return period, indicating a projected overall increase in future extreme-precipitation events. When data from all datasets are considered together, median change factors range within 1.04–1.18 for the period 2020–59 and within 1.04–1.23 for the period 2050–89, depending on the region, duration, and return period. Spatial patterns in median change factors were found to vary by dataset.

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USGS2026

Characterizing the annual cycle of steroid hormones in males from an invasive vertebrate (Python bivittatus) of management concern

South Florida's subtropical climate has facilitated the establishment of numerous invasive species, including the Burmese python ( Python bivittatus ). Despite decades of efforts to manage the invasive python population across South Florida, we lack a comprehensive understanding of their reproductive physiology, limiting the development of targeted control strategies. Here, we characterized seasonal patterns of testosterone (T) and corticosterone (CORT) in free-ranging adult male pythons and evaluated environmental correlates of hormone variation. Results indicate that T peaks before the onset of the breeding season and declines through the season to baseline levels in the non-breeding season. CORT did not show a clear seasonal trend but showed greater variability during the breeding season. These findings reveal that photoperiod and ambient temperature are key environmental correlates of male hormone cycles, contributing to our understanding of the endocrine phenology of a tropical ectotherm in a novel environment.

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USGS2026

Trends in subdaily to daily rainfall in Florida, 1990–2022

Changing rainfall patterns and intensifying rainfall extremes affect urban infrastructure and can increase flash-flood risk. Understanding how climate change has altered rainfall can support state and local agencies as they adapt and build resiliency. In this study, rainfall data from 23 weather stations in Florida were used to examine temporal and spatial trends over the period 1990–2022. Subdaily to daily rainfall events of durations 1, 2, 3, 6, 12, and 24 h were examined. A variety of statistical methods were applied to examine annual and seasonal trends, including quantile regression, extreme value analysis, run theory using the Mann–Kendall test, Sen–Theil slope, and Poisson and negative binomial tests, and threshold exceedance rates using generalized additive models. Using subdaily rainfall data posed challenges, including equipment failures, limited documentation of the quality assurance and control process, and potential measurement interferences. Results indicated that over 1990–2022, there was a decrease in hourly rainfall extremes but an increase at moderate quantiles. Overall, the number of rainfall events increased, particularly at shorter durations, but the mean total rainfall per event decreased. Additionally, the annual number of daily rainfall extremes showed more decreases than increases.

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USGS2026

Recent spread of introduced swamp eels (Percomorpha, Synbranchiformes, Synbranchidae) in Central Florida, USA, including first documented collections of cuchia, Ophichthys cuchia (Hamilton, 1822), in Florida

Swamp eels (Percomorpha, Synbranchiformes, Synbranchidae) were discovered in Florida in the 1990s and were considered established in the Greater Miami and Greater Tampa regions as early as 1997. We report detection of established populations of Sunda swamp eel, Monopterus javanensis Lacepède, 1800 and cuchia, Ophichthys cuchia (Hamilton, 1822) across multiple Orlando area watersheds in Central Florida. We report an additional occurrence of a single specimen of cuchia from Hillsboro Canal, Palm Beach County, Everglades drainage. Sampling was conducted from March 2023 through July 2025 in 52 Central Florida waterbodies, with emphasis on the middle and lower St. Johns River and the Upper Kissimmee River watersheds. Florida follows Louisiana and Texas as the third U.S. state between 2019 and 2023 to be found harboring established populations of cuchia. Live swamp eels, including both Sunda swamp eel and cuchia, have for decades been available for purchase at food markets throughout the United States, including Louisiana, Texas, and Florida. Ongoing trade in live swamp eels is likely leading to their introduction and establishment in the United States, with potential deleterious effects for aquatic ecosystems and human health.

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USGS2026

Bait baskets reduce trap disturbance and rebaiting for invasive Argentine black and white tegus (Salvator merianae) in the Greater Everglades Ecosystem, USA

Effective invasive species management can be informed by strategies that maximize removal while minimizing costs. In the southeastern United States, metal-mesh bait baskets are routinely used to protect chicken egg lures in traps targeting invasive Argentine black and white tegu lizards ( Salvator merianae ). These bait baskets are designed to reduce bait loss and nontarget species captures, potentially lowering rebaiting frequency and associated labor. Using data from a multi-year trapping effort and from a crossover experiment on the periphery of Everglades National Park, Florida, we evaluated the influence of bait baskets on tegu and nontarget capture rates, trap disturbance, and rebaiting needs. We found no evidence that bait baskets affected tegu or nontarget capture in either the multi-year or crossover experiment datasets, but they did reduce trap disturbance and rebaiting frequency in the multiyear dataset following their implementation in 2016. In the crossover experiment, rebaiting frequency declined only in the first trial. Overall, bait baskets may enhance trap efficiency by extending functional trap time and reducing maintenance costs.

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USGS2026

Continuous stream discharge, salinity, and associated data collected in the lower St. Johns River and its tributaries, Florida, 2023

The U.S. Army Corps of Engineers, Jacksonville District, deepened the St. Johns River channel in Jacksonville, Florida, to accommodate larger, fully loaded cargo vessels. The U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers, monitored stage, discharge, and (or) water temperature and salinity at 26 continuous data collection sites in the St. Johns River and its tributaries. This report contains information collected during the 2023 water year, from October 2022 to September 2023. Data at each site were compared for the length of the project, 8 years so far, and on a yearly basis to show the annual variability of discharge and salinity. The countywide annual rainfall for the 2023 water year was below the average yearly rainfall in four of the five counties. Annual mean discharge at 9 of the 10 tributary monitoring sites was lower for the 2023 water year than for the 2022 water year, and the annual mean flow at Broward River below Biscayne Boulevard near Jacksonville, Florida (USGS site number 02246751), was the lowest recorded at that site for the 8 years of data collection. The annual mean discharge for each of the main-stem sites was higher for the 2023 water year than for the 2022 water year and was above the average for the 8 years of data collected so far. Among the tributary sites, annual mean salinity was highest at Clapboard Creek above Buckhorn Bluff near Jacksonville, Fla. (USGS site number 302657081312400), the site closest to the Atlantic Ocean, and was lowest at Durbin Creek near Fruit Cove, Fla. (USGS site number 022462002), the site farthest from the ocean, for all years. Annual mean salinity data from the main-stem sites indicate that salinity decreased with distance upstream from the ocean, which was expected. Annual mean salinity for the 2023 water year was higher than or equal to that of the 2022 water year for all main-stem and tributary sites, except at St. Johns River at Dancy Point near Spuds, Fla. (USGS site number 294213081345300), which was lower. Three main-stem monitoring stations (USGS site numbers 295856081372301, 02245340, and 301057081414800) and six tributary monitoring stations (USGS site numbers 300803081354500, 022462002, 301204081434900, 02246459, 02246518, and 02246804) either had the highest annual mean salinities or tied with the highest annual mean salinities at their respective sites since data collection began.

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USGS2026

Accounting for emigration reveals high survival and bimodal size at departure from a loggerhead sea turtle (Caretta caretta) foraging area

The life history of hard-shelled sea turtles includes several ontogenetic shifts in habitat use and these complex permanent emigration patterns can impact estimates of stage-specific population rates, including survival. We developed several multistate mark recapture models to estimate survival of adult and juvenile loggerhead turtles from a coastal bay in the northern Gulf of America (also commonly referred to as the Gulf of Mexico) while, in some cases, accounting for permanent emigration and transient individuals. Our mark-recapture dataset consisted of 228 individual turtles with 37 total recaptures from 2011 to 2024. Of the models we fit, those that incorporated emigration produced higher estimates for annual survival than models that did not, and higher estimates than what is commonly seen in the literature for loggerheads. All models suggested a major permanent emigration pulse at the typical size of sexual maturity (70 cm straight carapace length) and another major pulse at > 90 cm. This bimodal pattern of departure may reflect differences in size at sexual maturity among loggerheads, possible genetic variability within the assemblage, or both. To assess the models’ ability to effectively recover true parameter values, we developed a simulation study of 50 randomly generated independent data sets under our specified models of similar sample size to our study dataset. Simulation results suggested that models that accounted for permanent emigration and transient individuals produced relatively unbiased estimates of survival, while models that did not often underestimated survival rates. Mark-recapture studies that may exhibit emigration and suffer from low recapture rates would benefit from auxiliary data collection such as acoustic telemetry detections to better estimate true rates of emigration and survival. Obtaining unbiased estimates of true survival by accounting for processes like emigration can support effective conservation of endangered long-lived species like loggerheads.

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USGS2026

Not so fatal attraction: Captive female Burmese Python lures do not improve wild python detection

The ongoing invasion of Python bivittatus (Burmese Python; henceforth, Python) across the Greater Everglades Ecosystem (GEE) has led to near total collapse of the affected mammal community over the past few decades. Management efforts to eliminate Pythons and control their spread have been hampered by the Python's low detectability, which may be improved by using a lure. In controlled settings, male Pythons show an attraction to the scent from reproductively active females. To test the effectiveness of using reproductively active female Pythons as a lure for attracting wild male Pythons in the field, we conducted a paired experiment with wild-caught female Pythons in pens and empty control pens. We monitored Python visitation at all sites using camera traps, which resulted in >3,000,000 photographs that we filtered to 4 independent detections of Pythons using AI software. Python detection was low at sites with female Pythons (3 observations) and control sites (1 observation) over 90 days at 12 sites. Stress associated with captivity may have halted reproductive females from producing pheromones, eliminating the chemosensory cue that lures males. Identifying and implementing husbandry techniques to reduce stress in wild-caught female Pythons could improve the effectiveness of this technique. Little is currently known about the chemical ecology of Pythons, and pheromonal communication in particular, and further research in this area could aid in the identification and production of effective, low-cost lures to increase detection and removal of this invasive species.

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USGS2026

Case report: Observations on expulsions from 20 years of radiotransmitter implantation in adult Burmese pythons

Background Radiotelemetry as a research tool has advanced our understanding of snake behavior and ecology. However, surgical transmitter implantation can lead to health complications for study animals, including expulsion, which may also interfere with research objectives. Two implantation methods include intramuscular and coelomic placements, and we evaluate expulsion rates of transmitters using these methods in Burmese pythons ( Python bivittatus ) in southern Florida. Results From 2005 to 2024, we implanted 305 transmitters in 142 adult Burmese pythons, primarily using intramuscular implantation ( n = 221), then transitioning to include coelomic placement ( n = 84). There were no observations of transmitter-related mortality. Overall, 98.7% of transmitters were retained, with a 1.3% expulsion rate ( n = 4 transmitters). Expelled transmitters were only observed in intramuscularly implanted transmitters from 4 of 13 gravid females. Conclusions We observed no mortality related to transmitter implantation and few instances of transmitter expulsion, indicating that both intramuscular and coelomic implantation techniques are effective for monitoring adult pythons in the wild. However, there is some risk that females may expel transmitters when gravid, and this risk may be reduced when implanting transmitters intracoelomically. Our findings may be useful for studies of other large-bodied snake populations worldwide where radiotransmitter implantation is appropriate and logistically feasible.

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USGS2026

Line transect distance sampling and genetic analyses reveal a small but genetically diverse coastal Gopher Tortoise (Gopherus polyphemus) population

Gopher Tortoises inhabit coastal systems, including barrier islands, across the southeastern U.S. St. Vincent National Wildlife Refuge is an uninhabited barrier island located off the coast of northwestern Florida. Although tortoises have been observed on the island, no information is available on the status of the population. We conducted a line transect distance sampling survey to evaluate the Gopher Tortoise population on St. Vincent Island. Additionally, we collected samples for genetic analyses from 11 individual tortoises captured opportunistically and via bucket traps on the island and 15 tortoises captured at nearby mainland sites. Surveys covered approximately 43% of the sampling frame and resulted in 55 burrows, 28 of which were occupied. The abundance estimate for the island was 52 tortoises (95% confidence interval [CI] = 27–100) and the density was relatively low at 0.071 tortoises/ha (95% CI = 0.037–0.136). Genetic analyses of two mtDNA markers identified a new haplotype unique to St. Vincent Island and another three haplotypes previously found across the southeastern U.S. The genetic composition of Gopher Tortoises on St. Vincent Island is representative of the entire southeastern U.S. but most closely aligns with tortoise populations east of the Apalachicola-Chattahoochee River system. Although the tortoise population on this island is small, the extent of seemingly appropriate habitat on the island and the genetic diversity of the population suggests the potential for growth with added management intervention.

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