Florida Panhandle Research Articles

High Prevalence of Clonal Reproduction and Low Genetic Diversity in Scutellaria floridana, a Federally Threatened Florida-Endemic Mint

The threatened mint Florida skullcap (Scutellaria floridana) is endemic to four counties in the Florida panhandle. Because development and habitat modification extirpated several historical occurrences, only 19 remain to date. To inform conservation management and delisting decisions, a comprehensive investigation of the genetic diversity and relatedness, population structure, and clonal diversity was conducted using SNP data generated by ddRAD. Compared with other Lamiaceae, we detected low genetic diversity (HE = 0.125-0.145), low to moderate evidence of inbreeding (FIS = -0.02-0.555), and moderate divergence (FST = 0.05-0.15). We identified eight populations with most of the genetic diversity, which should be protected in situ, and four populations with low genetic diversity and high clonality. Clonal reproduction in our circular plots and in 92% of the sites examined was substantial, with average clonal richness of 0.07 and 0.59, respectively. Scutellaria floridana appears to have experienced a continued decline in the number of extant populations since its listing under the Endangered Species Act; still, the combination of sexual and asexual reproduction may be advantageous for maintaining the viability of extant populations. However, the species will likely require ongoing monitoring, management, and increased public awareness to ensure its survival and effectively conserve its genetic diversity.

Is the Endangered Species Act living to its full potential? The reassessment of the conservation status and recovery of Macbridea alba Chapm. as a case study

Since 1988, the Cooperative Endangered Species Conservation Fund or “Section 6” fund facilitates partnerships between the U.S. Fish and Wildlife Service and state agencies that aim to provide data pertinent to the recovery of Endangered Species Act (ESA) protected species. Despite the success of these efforts, research for rare plants is chronically underfunded and many species experience long periods of research inactivity that hinders their conservation. One example is Macbridea alba Chapm. (white birds-in-a-nest, Lamiaceae, M. alba from hereon), a federally threatened and state endangered mint endemic to four counties within the Florida panhandle. The species is a candidate for delisting after 30 years of protection under the ESA, however a lack of up-to-date data associated with the species has continually challenged the implementation of effective conservation programs and prolonged the recovery process. The focus of this paper is to review the timeline of recovery goals for M. alba, present a summary of recent research findings (i.e., species distribution models, habitat associations, reproductive ecology), and identify achievements as well as persistent obstacles to recovery and delisting. Our research focused on 5 of 10 recovery actions listed in the recovery plan for M. alba. Our findings provide updated data and make novel contributions to the protection of M. alba that will prioritize and improve management efforts. Overall, our work highlights frequent barriers to the recovery and delisting of rare species, using an endemic plant species as a case-study. Importantly, we outline effective methods for the rapid assessment of at-risk plant species that due to enduring data gaps, face an uncertain future in listing and recovery. We hope our work provides a convincing case demonstrating the critical need for current and expanded ESA funding and encourages a diversity of individuals and institutions to participate in critical rare plant research to swiftly fill research gaps and expedite recovery of some of the rarest plant species across the United States.

Stand and tree characteristics influence damage severity after a catastrophic hurricane disturbance

Catastrophic wind disturbances can greatly impact the economic and ecological values of working forests worldwide. For example, Hurricane Michael caused severe economic damage in 2018 to commercial loblolly (Pinus taeda L.) and slash (Pinus elliotti Engelm.) planted pine stands in the southeastern U.S. This project examined the relative importance of prior management activities, stand characteristics, and soil and terrain attributes in predicting stand damage from a catastrophic hurricane event. We assembled data from land managers in coastal Alabama, the Florida panhandle, and South Georgia, on percent loss of trees after Hurricane Michael in over 400 stands, along with stand management history, and stand characteristics. Digital elevation models were utilized to determine terrain and hydrological characteristics of the landscape including aspect, channel distance, elevation, LS factor (slope and length steepness factor), slope angle, slope position, terrain ruggedness index, topographic wetness index, and wind exposition index. Random forest models were used to determine the relative accuracy of windspeed, management history, stand characteristics, and soil and terrain attributes in predicting stand damage. From the variables evaluated, stand density (as described by trees per acre), and tree height (as described by the average height of dominant and co-dominant trees) were among the most influential characteristics in predicting damage severity along with windspeed and linear distance from the coast. Stands with dominant heights > 14 m, trees per acre < 600 (trees per hectare < 1,483), and within 50 km of the coast were the most likely to experience severe damage. Topographic wetness index was the most influential terrain characteristic, with sands in wetter soils more likely to experience more severe damage. Recently thinned stands were slightly more vulnerable to severe damage. Results from this study can be used to develop vulnerability profiles for commercial pine stands in the coastal plain region in the southern U.S. region.

Spatial Application of Southern U.S. Pine Water Yield for Prioritizing Forest Management Activities

Forest management depends on forest condition data and the ability to quantify the impacts of management activities to make informed decisions. Spatially quantifying water yield (WY) from forests across large landscapes enables managers to consider potential WY changes when designing forest management plans. Current forest water yield datasets are either spatially coarse or too restricted to specific sites with in situ monitoring to support some project-level forest management decisions. In this study, we spatially apply a stand-level southern pine WY model over a forested landscape in the Florida panhandle. We informed the WY model with pine leaf area index inputs created from lidar remote sensing and field data, a spatial and temporal aridity index from PRISM and MODIS data, and a custom depth to groundwater dataset. Baseline WY conditions for the study area were created using the Esri and Python tools we developed to automate the WY workflow. Several timber thinning scenarios were then used to quantify water yield increases from forest management activities. The results of this methodology are detailed (10 m spatial resolution) forest WY raster datasets that are currently being integrated with other spatial datasets to inform forest management decisions.

Biomass and Productivity of Thalassia testudinum in Estuaries of the Florida Panhandle

Thalassia testudinum often dominates seagrass meadows of the Florida panhandle but few measurements of productivity, biomass, density, turnover or leaf area index in this region have been made. We targeted 5 estuaries located at similar latitudes, 30⁰ ± 0.3⁰N: Big Lagoon, Santa Rosa Sound, St. Andrew Bay, St. Joseph Bay, and St. George Sound. This study was one component of a collaborative partnership of state and local researchers examining factors preventing recovery in panhandle estuarine areas that had historically contained seagrass in the 1940s and 1950s. Measurements were made twice in 2016, once in June and then again in summer or fall, except in Santa Rosa Sound where measurements were made 3 times. In the estuaries sampled for the second time in July or August, aboveground productivity was greater than in June. St. Joseph Bay had the highest aboveground productivity (4.3 g/m2/d) and 1—sided leaf area index (4.2) while St. George Sound had the lowest values (0.41 g/m2/d and 1.0). Principal component analysis suggested that St. Andrew Bay, Big Lagoon and Santa Rosa Sound were the most similar, with higher values for shoot densities and leaf turnover and lower salinities and watershed:water ratios. St. Joseph Bay had high aboveground productivity and salinity, and low turbidity. St. George Sound had low aboveground productivity, high total suspended solids and the highest watershed:water ratio. These baseline productivity estimates will be useful to assess the success of restoration efforts targeting seagrasses in the Florida panhandle and evaluate impacts of climate change on seagrasses.

Remotely sensed measures of Hurricane Michael damage and adverse perinatal outcomes and access to prenatal care services in the Florida panhandle

BackgroundStudies of effects of hurricanes on perinatal outcomes often rely on approximate measures of exposure. This study aims to use observed damage from aerial imagery to refine residential building damage estimates, evaluate the population changes post landfall, and assess the associations between the extent of residential building damage and adverse perinatal outcomes and access to prenatal care (PNC) services. MethodsVital statistics data from the Florida Department of Health’s Office of Vital Statistics were used to align maternal geocoded address data to high-resolution imagery (0.5-foot resolution, true color with red, blue, and green bands) aerial photographs. Machine learning (support vector machines) classified residential roof damage across the study area. Perinatal outcomes were compared with the presence or absence of damage to the mother’s home. Log-binomial regression models were used to compare the populations living in and outside of high-risk/damage areas, to assess the population changes after Hurricane Michael, and to estimate the associations between damage after Hurricane Michael and adverse perinatal outcomes/access to PNC services. A semi-parametric linear model was used to model time of first PNC visit and increase in damage.ResultsWe included 8,965 women in analysis. Women with lower education and/or of Black or other non-White race/ethnicity were more likely to live in areas that would see high damage than other groups. Moreover, there was a greater proportion of births delivered by women living in the high-risk/damage area (> 25% damaged parcels after Michael) in the year before Michael than the year after Michael. Lastly, living in the area with relatively high damage increased the risk of having intermediate or inadequate PNC (adjusted Risk Ratio = 1.21, 95% CI: 1.03, 1.43), but not other adverse perinatal outcomes.ConclusionsAerially observed damage data enable us to evaluate the impact of natural disasters on perinatal outcomes and access to PNC services based on residential building damage immediately surrounding a household. The association between the extent of damage and adverse perinatal outcomes should be further investigated in future studies.

Human influence on bottlenose dolphin (Tursiops truncatus) strandings in the northern Gulf of Mexico

Human activity affects marine mammal stranding rates in two major ways; through human interaction (HI) that may lead to mortality and through search and response efforts that enable carcass detection. To better quantify the combined effects of these interacting human influences, we analyzed strandings for bottlenose dolphins (Tursiops truncatus) in the northern Gulf of Mexico (nGOM), an area of high cetacean strandings. To identify hotspots of human influence, we first determined the number of total and HI-related bottlenose dolphin strandings normalized to shoreline length in each nGOM U.S. state, which represent major response areas. To estimate the effects of response effort on stranding numbers (for HI and non-HI strandings), we used theDeepwater Horizonoil spill (DWHOS) as an established benchmark to compare periods of lower (pre-spill) and higher (post-spill) response effort. Strandings in Alabama waters were used as a case study to detail spatial and temporal variation due to human influences during the 39-year period of retrospective study. We found an increase in strandings from Louisiana through Alabama following the DWHOS. Non-oil related HI strandings increased in total number in AL, and they increased as a proportion of total strandings in Alabama (16%) and the Florida panhandle (12%). The increase in HI-related strandings in Alabama was driven by mortality of many types, but particularly fishery interactions and cases of apparent intentional harm. The Alabama case study clearly detected lower stranding numbers during periods of low or intermittent response coverage. Our findings are consistent with an overall increase in stranding numbers due to a combination of increased stranding occurrence and response effort following the DWHOS. Importantly, we provide evidence that HI-related standings increased independently from the DWHOS, with ongoing increases in at least one hotspot (Alabama). These findings provide a first step to parsing out different effects of human influences on stranding data for a common coastal cetacean. Our approach establishes baselines for future damage and recovery assessments, identifies areas where resources can be focused for management and education, and highlights the power of response and monitoring agencies to positively influence stranding datasets.

A Community Based Approach to Deter Childhood Obesity in Title 1 Schools

ABSTRACT Community development is an effort to build resources that increase inhabitants’ ability to improve their life quality. Obesity is a significant health risk to individuals and their communities. In 2016/2017, school screenings showed that 28.3% of first-graders, 35.4% of third-, and 14.1% of sixth-graders in a Florida Panhandle school district were overweight. Additional data revealed an increase in overweight individuals with large proportions of minorities or low-income students. To intervene, individuals from a Historically Black University respond to the structural inequality – obesity and education access to health care by offering nutritional education to ascertain the possibility of deterring childhood obesity using community-based programming. Over 870 students from Title 1 locations participated. A pretest/posttest was given, and T-test results revealed significant behavior changes. Community practitioners can offer educational programs to impact students’ health behaviors at risk of obesity.

County-Level Factors Associated With HPV Vaccine Coverage Among 11-Year-Olds to 12-Year-Olds Living in Florida in 2019

BackgroundIn the United States, human papillomavirus (HPV) vaccine initiation and up-to-date (UTD) status are associated with multiple factors at the individual level such as racial/cultural (e.g., race, immigration status), socioeconomic status (e.g., living below poverty level, education), and healthcare access (e.g., insurance status/type). HPV vaccination rates differ dramatically by US geographic areas and within states. To tailor interventions to local areas, it is important to understand county-level characteristics associated with HPV vaccination rates. MethodsUsing linear regression, we assessed the association between county-level HPV vaccination initiation and UTD rates for 11-year-olds to 12-year-olds in Florida (collected from the Florida SHOTS immunization registry) and county-level variables. Factors found significant in bivariate analysis and with a variance influence factors <4 were included in multivariable models. ResultsIn 2019, county-level HPV vaccine coverage among Florida 11-year-olds to 12-year-olds ranged from 31% to 92% initiation and 3%–36% UTD. Counties with the lowest HPV vaccine coverage were concentrated in Florida's North-Central and Panhandle regions. In multivariable models, counties with primarily rural populations had lower vaccination initiation and UTD coverage. Above and beyond the association with rurality, UTD coverage was associated with family physicians per 100,000 residents and uninsured or Medicaid-enrolled populations. DiscussionWhile Florida county-level HPV vaccine initiation rates among 11-year-olds to 12-year-olds varied by county in 2019, UTD rates remained universally low despite recommendations. Tailoring interventions toward healthcare access in rural communities may increase HPV vaccine coverage.

Microsite Habitat, Species Associations, and Habitat Suitability Model of a Globally Imperiled Shrub

Miller's witch-alder (Fothergilla milleri, Hamamelidaceae) is a newly described globally imperiled shrub that is known from disjunct populations in coastal Alabama, the panhandle of Florida, and one location in Georgia. Little is currently known about the natural history or ecology of the species. We conducted inventories of three populations of F. milleri in Alabama and Florida. A total of 3060 ramets were found; 45% were in one subpopulation ≤0.5 ha in area and 79% were in one population within an area of 4.5 ha. Low ramet counts in few locations makes the species particularly vulnerable to extinction due to stochastic events. Also, all seed capsules found within the surveys were infected by an aphid, which is possibly preventing sexual reproduction within the populations. Microsite habitat data indicated F. milleri grows in a unique transitional habitat between upland conifer forest and wetlands. The sites where extant populations of F. milleri inhabit tend to have acidic and well-drained soils with a high sand content. Further, many populations were under thick midstory vegetation. Thus, fire or other forms of removal may be needed to release those subpopulations before they may become shaded out. Lastly, a habitat suitability model was developed to better facilitate conservation efforts. However, only 0.5% of the study area was within the highest level of suitability. Fothergilla milleri is facing multiple threats that could lead to its extirpation from the wild, and direct and intense conservation action may be necessary to ensure F. milleri remains on the landscape.

The Long Christmas Dinner, Abbey Theatre, Dublin, Ireland

<i>The Long Christmas Dinner</i>, Abbey Theatre, Dublin, Ireland

Impacts of Hurricane Michael on Watershed Hydrology: A Case Study in the Southeastern United States

Hurricanes are one of the most significant threats to coastal plain forest ecosystems and urban communities of the southeastern U.S., but their implications for watershed hydrology are unclear. Hurricanes have the potential to alter water balances, causing extensive flooding, biogeochemical cycle disruption, and water quality degradation, saltwater intrusion, and increased nutrient sedimentation export in coastal watersheds. This case study focused on Hurricane Michael, a recent catastrophic event that impacted the Gulf coast, the Florida panhandle, southwestern Georgia, and southeastern Alabama. Through empirical (Double Mass Curve) and process-based ecohydrological modeling (WaSSI model) on long-term streamflow data, we explored whether vegetation damage caused by this hurricane resulted in an increase in streamflow two years after the extreme event. We found that monthly streamflow from the Chipola River watershed with an area of 2023 km2 did not change (&lt;6%) appreciably during the first two years following the storm, arguably because only a fraction of the gauged watershed lost substantial tree cover. However, spatially explicit hydrological modeling suggested that several sub-watersheds with the highest decreases in the Normalized Difference Vegetation Index (NDVI) significantly increased their monthly streamflow in 2019 by up to 22%. These modeled streamflow anomalies subsided by the second growing season when vegetation recovered. Overall, this study suggests that changes in vegetation cover after Hurricane Michael did not have lasting impacts on the hydrology of this watershed, and the hydrology of coastal watersheds may be more resilient to hurricane disturbances than previously thought.

Germination Response of Three Florida Panhandle Coastal Dune Plants to Salinity

Campbell-Martínez, G.E.; Thetford, M., and Miller, D., 2022. Germination response of three florida panhandle coastal dune plants to salinity. Journal of Coastal Research, 38(3), 585–591. Coconut Creek (Florida), ISSN 0749-0208. Coastal dunes and their ecosystem services are threatened by human pressures warranting active restoration. Understanding dune plant germination responses to salinity is important when considering plant species and direct seeding locations for coastal dune restoration projects. The germination response of three Florida panhandle native coastal dune plant species to various salinity concentrations (0%, 0.25%, 0.50%, 0.75%, and 1% weight per volume) were tested. Species included were coastalplain honeycombhead (Balduina angustifolia (Pursh)B.L.Rob.), coastalsand frostweed (Crocanthemum arenicola (Chapm.)Barnhart), and squareflower (Paronychia erecta (Chapm.)Shinners). Seeds were germinated within germination boxes, placed in growth chambers under species-specific temperatures with a daily 12-hour photoperiod, and monitored weekly for 4 weeks. Germination responses to salinity were species-specific. Coastalplain honeycombhead had intermediate salt tolerance (highest germination at 0%–0.50% salinity), coastalsand frostweed was the least salt tolerant (highest germination at 0%–0.25% salinity), and squareflower was the most salt tolerant species in respect to germination (high germination across all salinities). Germination was delayed for all species at the highest salinity concentrations (0.75%–1%). However, for all three species, at least one-third of all seeds (>39%) at all salinity concentrations germinated by week 4. Results suggest germination for seeds of these species is possible in saline conditions documented within coastal areas before and after hurricane overwash. Future dune restoration studies for these species should test direct seeding of these plants under field conditions.

Hurricane Michael and Adverse Birth Outcomes in the Florida Panhandle: Analysis of Vital Statistics Data – Addendum

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Determination of Recharge Areas That Supply Decades Old Groundwater to Creeks Inhabited by the Threatened Okaloosa Darter

The Okaloosa darter (Etheostoma okaloosae) is a diminutive, perch-like, benthic fish that inhabits only six small, clear, and shallow creek systems that flow almost entirely within Eglin Air Force Base in the panhandle of northwest Florida. Listed as Endangered by the U.S. Fish and Wildlife Service (USFWS) in 1973, improvements in erosion control and habitat restoration led to the Okaloosa darter being downlisted from Endangered to Threatened in 2011. However, the long-term management of the species is hampered by the lack of knowledge of the spatial extent of the recharge areas that ultimately support creek flow through groundwater discharge. To address this lack of data, we collected groundwater samples from the sand and gravel aquifer beneath 11 headwater and 11 downgradient sites across six creek basins during February and December 2020. The groundwater samples were collected from 1 to 1.2 m beneath the creek bottom. Concentrations of sulfur hexafluoride (SF6) were analyzed and used to calculate groundwater age (residence time), and indicated that at the 11 headwater sites, recharge occurred between 11 and 28 years ago. Groundwater ages in downgradient parts of the same creeks indicated that recharge occurred between 5 and 25 years ago. When combined with representative values of hydraulic conductivity for the sand and gravel aquifer, the ages reveal that the extent of the maximum recharge distance from the sampling sites ranged from about 222 to 2011 m from the creeks. This new information can be used by natural resource managers as additional evidence to support the USFWS Recovery Plan and proposed delisting of the Okaloosa darter from the Endangered Species List. Moreover, these results may also be useful to fisheries biologists to incorporate groundwater inputs to facilitate fisheries management.

Arrival condition and refueling performance of long-distance migratory songbirds at a spring stopover site in the eastern Gulf of Mexico

Barrier islands along the northern Gulf coast provide critical stopover habitats for Nearctic–Neotropical migratory songbirds using a spring trans-Gulf migration strategy. Islands bordering Apalachicola Bay, Florida, project southward into the Gulf of Mexico providing an opportunity for first landfall. In 2013 and 2014, we studied spring stopover ecology on St. George Island, Florida. We provide a detailed description of the arrival body condition and fuel deposition rates of 8 species of migratory birds. We used 3 approaches to measure fuel deposition rate: (1) estimated an hourly rate of mass change by regressing body mass or scaled body mass by time of day, (2) estimated a daily rate of mass change by examining body mass of recaptured individuals, and (3) for 4 species, measured plasma triglyceride concentrations as a proxy of individual refueling rate. The majority of migratory birds in the eastern Gulf of Mexico arrived in poor body condition with depleted fat and muscle stores. We found no significant changes in body mass or scaled body mass as the day progressed, except for Indigo Bunting (Passerina cyanea), which gained mass throughout the day. Recapture rate was low on St. George Island (<5%), but most recaptured individuals tended to lose mass. Using plasma triglyceride concentration, we found that refueling rate for Gray Catbird (Dumetella carolinensis) declined throughout the day. We found no relationship between body condition and refueling rate in Gray Catbird or Catharus thrushes. Our results suggests that long-distance migratory birds arriving on St. George Island after a nonstop migratory flight may be physiologically challenged due to poor body condition. Our results provide the first quantitative assessment of songbird refueling performance on Florida panhandle barrier islands and reinforce the importance of Gulf of Mexico barrier islands as critical stopover sites for long-distance migrants in poor body condition.

A Study in Performing Big Data Analytics with Limited Resources

Data analytics are usually the purview of large organizations with significant human and computational resources. The purpose of the article is to identify how organizations with limited resources, including limited computing power and bandwidth, can carry out meaningful data analytics at a granularity that fits their specific needs. This paper presents a case study in creating and maintaining a COVID dashboard for a 5-county area in the Panhandle of Florida, using only free software and publication platforms. Results of this study are informative for any local or regional entity needing focused data analytics.

Future Flood Risk Exacerbated by the Dynamic Impacts of Sea Level Rise Along the Northern Gulf of Mexico

AbstractA growing concern of coastal communities is increased flood risk and non‐monetary consequences due to climate‐induced impacts such as sea level rise (SLR). Previous efforts have discussed the importance of future flood risk quantification using broad aggregations of monetary loss with “bathtub” SLR models rather than more physically based modeling approaches. Here we quantify actual impacts to coastal communities at the census block level using a dynamic, high‐resolution, bio geophysical modeling framework for four SLR scenarios for the year 2100. This framework accounts for future sea‐levels, landscape change, and urbanization to quantify the 1% and 0.2% annual exceedance probability (AEP) water levels. The computed AEP water levels were used to quantify building damage and populations of displaced people and people requiring long‐term shelter across the Northern Gulf of Mexico (NGOM) (Mississippi, Alabama, and the Florida panhandle). The increase in damaged buildings under SLR is linear, with an increase of 16,367 damaged buildings per 1 m of SLR (R2 = 0.96) for the 1% AEP flood. The rate increases to 24,981 damaged buildings per 1 m of SLR (R2 = 0.96) for the 0.2% AEP, on average. The increase in displaced people across the NGOM is 8,056 people per meter of SLR, and people requiring shelter is 300 per meter of SLR. The results in this work highlight the varying levels of risk across the NGOM and the change in risk under climate change‐induced impacts.

Impacts of Multiple Hurricanes and Tropical Storms on Watershed Hydrological Processes in the Florida Panhandle

Hurricanes and tropical storms (TS) are infrequent but disastrous events to human lives, social activities, and terrestrial ecosystems in coastal regions. Using the Environmental Protection Agency (US-EPA)’s Hydrologic and Water Quality System (HAWQS) model, principal component analysis (PCA), and principal factor analysis (PFA), we estimated impacts of multiple hurricanes and TS on hydrological processes in agricultural and forested watersheds. Five hurricanes and four TS that passed near or through the Apalachicola–Chattahoochee–Flint River basin (ACFRB) of the Florida panhandle from 1966 to 2018 were selected to estimate their impacts on rainfall, potential evapotranspiration (PET), evapotranspiration (ET), soil water percolation, surface runoff, stream discharge, groundwater recharge, and water yield (WYLD). Simulations showed that the category of hurricanes was not highly related to the amounts of rainfall, runoff, discharge, and WYLD. Based on PCA and PFA, PET and ET were highly and negatively, rainfall and discharge were highly and positively, and percolation, runoff, groundwater recharge and WYLD were moderately and positively affected by the hurricanes and TS at the ACFRB in the recent 50 years. This study provides water resource managers with critical insights into how multiple hurricanes and TS affected hydrological processes in agricultural and forested watersheds of the coastal region.

Hurricane Michael and Adverse Birth Outcomes in the Florida Panhandle: Analysis of Vital Statistics Data.

The aim of this study was to examine birth outcomes in areas affected by Hurricane Michael. Vital statistics data of 2017-2019 were obtained from the state of Florida. Births occurring in the year before and after the date of Hurricane Michael (October 7, 2018) were used. Florida counties were divided into 3 categories reflecting extent of impact from Hurricane Michael. Birth outcomes including incidence of preterm birth (PTB), low birth weight (LBW), and small for gestational age (SGA) were also compared before and after Hurricane Michael. Spontaneous and indicated PTBs were distinguished based on previously published algorithms. Multiple regression was used to control for potential confounders. Both LBW (aRR 1.19, 95% CI: 1.07, 1.32) and SGA (aRR 1.11, 95% CI: 1.01, 1.21) were higher in the year after Michael than the year before in the most-affected area; a similar effect was not seen in other areas. A stronger effect was seen for exposure in the first trimester or in the 2 months after Michael than in the second or third trimester. Consistent with many previous studies, this study of Hurricane Michael found an effect on fetal growth.