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A leading human-related threat to the Florida manatee Trichechus manatus latirostris is collisions with watercraft, which account for 20-25% of reported mortalities. Quantitative threat assessments do not include information on all known manatee-watercraft interactions. These interactions often result in sublethal wounding, usually leaving multiple fresh external wounds in a variety of patterns. These wounds then resolve into well-healed scars. We characterized and quantified watercraft-related scar patterns (1 pattern = 1 strike event) on 2935 nonperinatal carcasses (>150 cm total length) that were recovered from 2007 through 2016 to compare the number of patterns by life stage, sex, and population region and across years. We used generalized linear mixed models to examine the effects of several factors on the probability carcasses having scars and on the number of scar patterns per carcass. The models indicated that approximately 96% of adults, approximately 70% of subadults, and approximately 34% of calves had watercraft-related scars. The raw data showed that 1 in 4 adults had been hit 10 or more times; 5 adult carcasses bore evidence of 40 or more strikes. On average, adult females had more scar patterns than did adult males. Manatees on Florida’s west coast had more scar patterns than did those on the east coast, while carcasses from the less populated Everglades had significantly fewer scar patterns than did those from the rest of the state. These results improve our understanding of the extent of sublethal injury of the Florida manatee caused by boat strikes.

Smalltooth sawfish Pristis pectinata use southwest Florida nurseries during at least their first 2 to 3 yr, and understanding region-specific habitat use patterns is important for effective management. Research occurred in 2 nurseries within the Charlotte Harbor estuarine system: the Caloosahatchee River, a highly human-altered nursery, and a more natural nursery, the Peace River. Between 2010 and 2013, a total of 148 juveniles ranging from 70.8 to 218.7 cm stretch total length were caught in gill nets, and 133 were acoustically tagged. The probability of encountering a sawfish during sampling was most influenced by season in both nurseries (highest during spring and summer), followed by dissolved oxygen in the Caloosahatchee River, and salinity and temperature in the Peace River. Temperature had lasting, atypical effects on movements when severe cold events occurred during the study. Outside of these disturbances, sawfish used all habitats available to them in both nurseries, but tended to reside in perennial high-use areas called nursery hotspots. Acoustic monitoring showed that juveniles gradually moved between 4 hotspots along a 20 river kilometer stretch of the Caloosahatchee River with seasonal changes in freshwater inflows or sometimes suddenly in response to large flow events. In contrast, sawfish in the Peace River remained associated with one nursery hotspot year-round. Reasons for these inter-nursery variations are attributed to differences in geomorphology and freshwater inflow regimes. This study illustrates that a full understanding of the life history of a species and the development of a conceptual model requires investigation of the species on a broad spatial scale. This consideration is important to avoid overgeneralization of habitat use patterns between nurseries.

Genetic rescue-an increase in population fitness following the introduction of new alleles-has been proven to ameliorate inbreeding depression in small, isolated populations, yet is rarely applied as a conservation tool. A lingering question regarding genetic rescue in wildlife conservation is how long beneficial effects persist in admixed populations. Using data collected over 40 years from 1192 endangered Florida panthers (Puma concolor coryi) across nine generations, we show that the experimental genetic rescue implemented in 1995-via the release of eight female pumas from Texas-alleviated morphological, genetic, and demographic correlates of inbreeding depression, subsequently preventing extirpation of the population. We present unequivocal evidence, for the first time in any terrestrial vertebrate, that genetic and phenotypic benefits of genetic rescue remain in this population after five generations of admixture, which helped increase panther abundance (> fivefold) and genetic effective population size (> 20-fold). Additionally, even with extensive admixture, microsatellite allele frequencies in the population continue to support the distinctness of Florida panthers from other North American puma populations, including Texas. Although threats including habitat loss, human-wildlife conflict, and infectious diseases are challenges to many imperiled populations, our results suggest genetic rescue can serve as an effective, multi-generational tool for conservation of small, isolated populations facing extinction from inbreeding., (© 2024. The Author(s).)

Spotted seatrout, a popular recreational sport fish in the southeastern United States, are affected by freshwater flow conditions and the availability of estuarine habitat. However, the relative influence of these factors, particularly on early life stages of seatrout, remains uncertain. We used generalized linear models to quantify relationships between the probability of encountering juvenile spotted seatrout during seine surveys and various factors, including freshwater inflow conditions, the availability and richness of estuarine habitats (seagrass, salt marsh, oyster beds) around (400-m radius) fish collection sites (seascape-scale context), as well as distance to the nearest inlet to the Gulf of Mexico (estuary-scale context) across shallow waters (< 1.5 m depth) of Apalachicola Bay, Florida. Modelling results showed a consistent positive correlation between seagrass area and the probability of encountering juvenile seatrout (all four size classes from 15mm-200mm Standard Length (SL)). The probability of encountering the two smallest juvenile seatrout size classes (15-50mm and 51-100mm SL) was also related to freshwater inflow conditions, particularly within a 3-month period prior to and including peak recruitment. Freshwater inflow may affect early life stages by influencing passive transport of eggs and larvae, planktonic food availability, and predation pressure through increases in turbidity. In contrast, encounter probabilities of the two larger size classes (101-150mm and 151-200mm) were unrelated to freshwater inflow. Inflow-related processes may be less important to the larger juveniles as they have typically settled out of the plankton into benthic habitats which provide refuge from predation and abundant benthic food sources which are not as closely tied to freshwater inflow effects. In addition, models revealed that occurrence of the larger juveniles was related to the availability of nearby habitat types such as oyster beds and salt marshes, suggesting that increased mobility as seatrout grow may allow them to use nearby habitat types as additional sources of food and refuge. These results add to a growing body of literature aimed at understanding the influence of freshwater inflow as well as seascape context on vulnerable juvenile life stages of fishery species to provide more informed strategies for freshwater inflow management and habitat conservation., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Whaley et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Subtropical Florida blue crabs, Callinectes sapidus, exhibit differing life history traits compared to their temperate counterparts, likely influencing symbiont infection dynamics. Little information exists for Florida C. sapidus symbiont profiles, their distribution among various habitats, and influence on crab condition. Using histopathology, genomics, and transmission electron microscopy, we describe the first symbiont profiles for Florida C. sapidus occupying freshwater to marine habitats. Twelve symbiont groups were identified from 409 crabs including ciliophorans, digenean, microsporidian, Haplosporidia, Hematodinium sp., Nematoda, filamentous bacteria, gregarine, Callinectes sapidus nudivirus, Octolasmis sp., Cambarincola sp., and putative microcell. Overall, 78% of C. sapidus were documented with one or more symbiont groups demonstrating high infection rates in wild populations. Environmental variables water temperature and salinity explained 48% of the variation in symbiont groups among Florida habitats, and salinity was positively correlated with C. sapidus symbiont diversity. This suggests freshwater C. sapidus possess fewer symbionts and represent healthier individuals compared to saltwater populations. Crab condition was examined using the reflex action mortality predictor (RAMP) to determine if reflex impairment could be linked to symbiont prevalence. Symbionts were found positively correlated with crab condition, and impaired crabs were more likely to host symbionts, demonstrating symbiont inclusion may boost predictive ability of the RAMP application. The microsporidian symbiont group had a particularly strong effect on C. sapidus reflex response, and impairment was on average 1.57 times higher compared to all other symbiont groups. Our findings demonstrate the importance of considering full symbiont profiles and their associations with a spatially and temporally variable environment to fully assess C. sapidus population health., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Inc.)

Along the Florida reef tract, stony-coral-tissue-loss disease (SCTLD) has caused extensive mortality of more than 20 scleractinian coral species. The pathogen is unknown, but its epizoology indicates that the disease, facilitated by water currents, has progressed linearly along the tract, affecting reefs at the scale of hundreds of kilometers. To inform ongoing disease mitigation efforts, we examined the small-scale spatial and temporal epidemiology of SCTLD. We established a series of sites in the middle Florida Keys at offshore and inshore locations that had not yet shown signs of SCTLD. We then conducted high-frequency monitoring from February 2018 through September 2019 and documented the onset of SCTLD and its progression through the sites. SCTLD was first observed at one site during early February 2018 and by early March 2018 all sites showed signs of the disease. A dynamic multistate model suggested that disease transmission was independent of coral density and found little evidence of a positive association between a colony showing signs of SCTLD and the condition or distance to its neighboring colonies. The model did, however, indicate that the probability of a colony showing signs of SCTLD increased with increasing colony surface area. These results are consistent with the water-borne transmission of a pathogen that progressed rapidly through the survey area. However, by the end of our survey the progression of SCTLD had slowed, particularly at inshore sites. Many affected colonies no longer exhibited progressive tissue mortality typical of the disease, suggesting the existence of differentially resilient colonies or coral communities, meriting their use for future coral rescue and propagation and disease research. These results are useful for refining ongoing SCTLD mitigation strategies, particularly by determining when disease rates are sufficiently low for direct intervention efforts designed to arrest disease progression on individual coral colonies will be most effective., Competing Interests: The authors have declared that no competing interests exist.

Aims: This study aimed to establish the early healing and neointimal transformation profile of the new polymer-free BioFreedom stent through sequential optical coherence tomography (OCT) within the first nine months following stent implantation., Methods and Results: We randomly assigned 104 BFS recipients to one of five groups with angiography and OCT follow-up at 1, 2, 3, 4, or 5 months, together with another follow-up for all at nine months. The primary endpoint was the degree of OCT-detected strut coverage at nine months. From 1, 2, 3, 4, and 5 months, median neointimal strut coverage increased from 85.8, 87.0, 88.6, 96.8 to 97.1%, respectively, to 99.6% (IQR 98.2-99.9) at nine months. At nine months, median percent neointimal volume was 13.0% and angiographic late lumen loss was 0.21±0.30 mm. Major adverse cardiac events (MACE) were limited to one non-cardiac death, one non-ST-elevation myocardial infarction not related to BFS, and two target lesion revascularisations without stent thrombosis (MACE rate 4.0%)., Conclusions: Neointimal strut coverage of the BFS was rapid and the BFS was shown to be clinically safe and effective.

Background: Durable polymers used in drug-eluting stents are considered a potential cause of hypersensitivity inflammatory response adversely affecting stent healing. Using a sequential follow-up with optical coherence tomography, we compared the differences in healing profiles of 2 drug-eluting stents with a biodegradable or durable polymer., Methods and Results: Sixty patients with multivessel disease were prospectively enrolled to receive both study stents, which were randomly assigned to 2 individual vessels, a Resolute Integrity zotarolimus-eluting stent with a durable BioLinx polymer and a BioMatrix NeoFlex Biolimus A9-eluting stent with a biodegradable polylactic acid polymer. Optical coherence tomography was performed at baseline, then in 5 randomly assigned monthly groups at 2 to 6 months, and at 9 months in all patients. The primary end point was the difference in optical coherence tomography strut coverage at 9 months. Key secondary end points included angiographic late lumen loss and composite major adverse cardiac events (cardiac death, myocardial infarction, target lesion revascularization, and definite or probable stent thrombosis) at 9 months. Resolute Integrity zotarolimus-eluting stent showed significantly better strut coverage than BioMatrix NeoFlex Biolimus A9-eluting stent at 2 to 6 months ( P <0.001) and less variance of percent coverage at 9 months, 99.7% (interquartile range, 99.1-100) versus 99.6% (interquartile range, 96.8-99.9; difference, 0.10; 95% confidence interval, 0.00-1.05; P <0.001). No significant difference was observed in major adverse cardiac events or angiographic end points., Conclusions: Despite having a durable polymer, Resolute Integrity zotarolimus-eluting stent exhibited better strut coverage than BioMatrix NeoFlex Biolimus A9-eluting stent having a biodegradable polymer; both showed similar antiproliferative efficacy. This novel, longitudinal, sequential optical coherence tomography protocol using each patient as own control could achieve conclusive results in small sample size., Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01742507., (© 2018 American Heart Association, Inc.)

Background: Current monotherapy drug-eluting stents are associated with impaired healing, neoatherosclerosis, and late stent thrombosis. The healing profile and neointimal transformation of the first dual-therapy endothelial progenitor cell-capturing sirolimus-eluting stent are unknown., Methods and Results: In this prospective, single-center study, 61 patients treated with the Combo stent had optical coherence tomography at baseline, early follow-up (4 monthly groups in a 1:2:2:1 ratio from 2 to 5 months), 9 months, and 24 months. Optical coherence tomography early strut coverage increased from 77.1% to 92.5% to 92.7% to 94.9% between 2 and 5 months. At 9 months, the major adverse cardiac event rate was 1.64%, and angiographic in-stent late loss was 0.24 mm (0.08-0.40). The 36-month major adverse cardiac event rate was 3.3%. From 9 to 24 months, neointimal regression was confirmed by optical coherence tomography: neointimal thickness (median [first quartile and third quartile]), 0.14 mm (0.08 and 0.21) versus 0.12 mm (0.07 and 0.19), P<0.001; neointimal volume, 29.9 mm(3) (22.1 and 43.2) versus 26.2 mm(3) (19.6 and 35.8), P=0.003; and percent neointimal volume, 17.8% (12.2 and 21.2) versus 15.7% (11.2 and 19.4), P=0.01. No definite or probable late stent thrombosis was recorded., Conclusions: With additional endothelial progenitor cell-capturing technology, the Combo stent exhibits a unique late neointimal regression (from 9 to 24 months) that has not been reported in any drug-eluting stents, translating into good 36-month clinical results with minimal restenosis and no late stent thrombosis. This is the first study testing the concept of using a longitudinal sequential optical coherence tomography protocol to continuously document early healing profile and late neointimal transformation, predicting long-term outcomes of a new novel stent platform., Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifiers: NCT01274234, NCT01756807, and NCT02263313., (© 2016 American Heart Association, Inc.)

The southeastern United States has experienced severe, recurrent drought, rapid human population growth, and increasing agricultural irrigation during recent decades, resulting in greater demand for the water resources. During the same time period, freshwater mussels (Unioniformes) in the region have experienced substantial population declines. Consequently, there is growing interest in determining how mussel population declines are related to activities associated with water resource development. Determining the causes of mussel population declines requires, in part, an understanding of the factors influencing mussel population dynamics. We developed Pradel reverse-time, tag-recapture models to estimate survival, recruitment, and population growth rates for three federally endangered mussel species in the Apalachicola-Chattahoochee-Flint River Basin, Georgia. The models were parameterized using mussel tag-recapture data collected over five consecutive years from Sawhatchee Creek, located in southwestern Georgia. Model estimates indicated that mussel survival was strongly and negatively related to high flows during the summer, whereas recruitment was strongly and positively related to flows during the spring and summer. Using these models, we simulated mussel population dynamics under historic (1940-1969) and current (1980-2008) flow regimes and under increasing levels of water use to evaluate the relative effectiveness of alternative minimum flow regulations. The simulations indicated that the probability of simulated mussel population extinction was at least 8 times greater under current hydrologic regimes. In addition, simulations of mussel extinction under varying levels of water use indicated that the relative risk of extinction increased with increased water use across a range of minimum flow regulations. The simulation results also indicated that our estimates of the effects of water use on mussel extinction were influenced by the assumptions about the dynamics of the system, highlighting the need for further study of mussel population dynamics.

Coordinated proliferation of lung cells is required for normal lung growth and differentiation. Chronic injury to developing lung may disrupt normal patterns of cell proliferation. To examine patterns of cell proliferation in injured developing lungs, we investigated premature baboons delivered at 125 days gestation (approximately 67% of term) and treated with oxygen and ventilation for 6, 14, or 21 days (PRN). Each PRN treatment group contained 3 or 4 animals. During normal in utero lung development, the proportion of proliferating lung cells declined as measured by the cell-cycle marker Ki67. In the PRN group, the proportion of proliferating lung cells was 2.5-8.5-fold greater than in corresponding gestational controls. By 14 days of treatment, the proportion of cells that expressed pro-surfactant protein B (proSP-B) was ~2.5-fold greater than in gestational controls. In the PRN group, 41% of proliferating cells expressed proSP-B compared with 5.8% in the gestational controls. By 21 days of treatment, proliferation of proSP-B-expressing epithelial cells declined substantially, but the proportion of proliferating non-proSP-B-expressing cells increased approximately sevenfold. These data show that the development of chronic lung disease is associated with major alterations in normal patterns of lung-cell proliferation.