Wallin, D.O. and Bergner, J., 2025. Evaluation of recreational impacts on eelgrass using unoccupied aerial systems and virtual ground truth data. Journal of Coastal Research, 41(2), 187–198. Charlotte (North Carolina), ISSN 0749-0208.

Eelgrass (Zostera sp.) provides a wide variety of ecosystem services and habitat for many organisms. Eelgrass distribution can be adversely affected by many factors, including recreational boating activities. Imagery acquired using unoccupied aerial systems (UAS) has recently been adopted as an effective approach for monitoring eelgrass in nearshore marine environments. Effective use of UAS imagery for eelgrass monitoring requires ground truth data, which can be quite challenging to collect during brief low-tide events. This project presents a novel approach for collecting “virtual” ground truth data that was used in conjunction with UAS imagery to quantify the percent coverage of eelgrass and algae in the intertidal and upper subtidal zones and changes in coverage in response to recreational impacts and seasonal dynamics.

Palaparthi, J.; Briggs, T.R., and Hauptman, L., 2025. Variability of beach sediment and sea turtle nesting, hatching, and emergence patterns during the 2019 nesting season northern Palm Beach County, Florida, U.S.A. Journal of Coastal Research, 41(2), 199–213. Charlotte (North Carolina), ISSN 0749-0208.

Beaches provide essential nesting habitat for threatened and endangered sea turtles. Palm Beach County, Florida is a medium- to high-density nesting location for loggerhead, green, and leatherback sea turtles. However, three quarters of the beaches in Palm Beach County are classified as critically eroding, restored by adding sediment as beach nourishment. Sediment is often used from upland mines, an offshore borrow source, or an adjacent inlet. The textural properties of sediment from these different borrow sources can vary, which may influence substrate temperature and potentially affect the hatching success of incubating sea turtle clutches. To support a healthy ecosystem, it is important to quantify the physical characteristics of placed sediments and evaluate whether there is any influence on successful sea turtle nesting, hatching, or emergence success. This study evaluates spatiotemporal variability of sediment characteristics (i.e. mean grain size, sorting, carbonate content) and the substrate temperature of nourished and non-nourished beaches in northern Palm Beach County, Florida to determine whether there is an influence on sea turtle nesting, hatching, and emergence success. Loggerhead sea turtles (Caretta caretta) were the only species found to have a correlation among nesting, hatching, and sediment characteristics. A hot-spot analysis in GIS identified a preference of leatherbacks (Dermochelys coriacea) to nest on nourished beaches, whereas greens (Chelonia mydas) and loggerheads preferred the non-nourished beaches. Results from this study can aid in understanding best management practices for the future of sandy beaches that provide optimal habitat for sea turtle reproduction efforts.

Abishag, M.M.; Faizullah, M.M., and Balasundari, S., 2025. Impact of low-temperature storage on growth characteristics of marine diatom, Navicula sp. Journal of Coastal Research, 41(2), 214–222. Charlotte (North Carolina), ISSN 0749-0208.

In fish and shellfish hatcheries, the traditional methods of microalgal preservation by subculturing are labour intensive and result in decrease of cell size and viability. Hence, long-term preservation without deterioration of genetic and nutritional quality of the commercially important diatom, Navicula sp., can be achieved through low-temperature preservation techniques. This study aimed to assess the growth characteristics of Navicula sp. preserved at different low temperatures to identify the best protocol for preservation. Navicula sp. was isolated from shrimp ponds and subjected to freezing at –4°C, –20°C, and –196°C at two different concentrations of dimethyl sulphoxide (Me₂SO; 5% and 10%) and freezing rates (direct plunging and two-step freezing at –196°C) for 30 days. Growth characteristics and viability were assessed postthawing. Concerning the biomass at the exponential phase, cells preserved at –20°C and –196°C with 5% cryoprotectant exhibited comparatively higher biomass than the cells preserved with 10% cryoprotectant at the same temperature (p ≤ 0.05) upon thawing. The highest biomass and cell density were observed in the thawed Navicula sp. preserved at –196°C with 5% Me₂SO after the two-step freezing protocol (p ≤ 0.05). However, the cells preserved at higher temperature regimes, at –4°C and –20°C, had higher carotenoid concentrations when compared with cells preserved at –196°C. The cells preserved at –196°C after the two-step freezing protocol were viable for a longer period (12 d) when compared with cells preserved at –20°C (7 d). Thus, considering the growth characteristics, Navicula sp. can be preserved at –196°C with 5% Me₂SO after the two-step freezing protocol for long-duration preservation for use as stock culture for feeding in shrimp hatcheries and nurseries and for further biotechnological interventions.

Ling, C.; Yazdani, N.; Beneberu, E., and Koliou, M., 2025. Experimental evaluation of elevated home slabs for flood mitigation. Journal of Coastal Research, 41(2), 223–234. Charlotte (North Carolina), ISSN 0749-0208.

Elevating concrete slab-on-grade (SOG) homes above the base flood elevation is one of the well-known methods of mitigating damage caused by repeated flooding events along the Gulf of Mexico and other coastal areas. This is typically accomplished by placing new pier supports with additional beams, if necessary, under a raised slab home. As a result, the slab support conditions are changed from uniform soil to column and beam supports, leading to unanticipated stress changes, concrete cracks, and slab failure. Past studies attempted to study the effects of changing the support conditions on the SOG. However, those specimens did not represent the slabs used in real-world scenarios. Thus, the current study experimentally evaluated the structural performance of elevated home slabs built per the construction practice along the Texas Gulf Coast under uniform floor live load. In addition, the application of carbon fiber reinforced polymer (CFRP) retrofitting that would apply to capacity-compromised SOG homes was investigated. The first specimen had four panels with monolithically poured grade beams around each panel, while the second specimen had two panels with monolithically poured grade beams supported by additional steel beams. The second specimen also included CFRP laminate retrofitting under one of the panels. The slabs were supported by concrete block masonry piers with various contact conditions. It was found that the typical contractor-determined elevation layout can withstand the building code–mandated floor live load. Increased column spacing decreased slab load capacity as expected. The CFRP layer did not contribute to the moment capacity as the concrete slab itself was able to carry the applied loads, and the CFRP layer was not engaged. The experimental results were then used to calibrate numerical software models for further study into the behavior of existing slabs.

Lowe, S.A.; Cercone, C.; McKeon, B., and Corrao, J., 2025. Erosion, flooding, and storm surge on the South Shore of Staten Island, New York City. Journal of Coastal Research, 41(2), 235–246. Charlotte (North Carolina), ISSN 0749-0208.

The South Shore of Staten Island in New York City is extremely vulnerable to the impact of climate change. The area is susceptible to coastal flooding, storm surge, and erosion, and was devastated by Hurricane Sandy in 2012. Sea-level rise and more frequent extreme events will only exacerbate the risk. Proposals to protect the South Shore include a complex onshore system with a buried seawall. These measures should offer flood and surge protection but will not address erosion. Offshore breakwaters could protect against storm wave damage and potentially rebuild the shoreline by reversing the effects of erosion. However, breakwaters are not known as effective storm surge barriers. To investigate the interaction of breakwaters and storm surge, a series of physical experiments was conducted. Four different breakwater systems were tested and evaluated on the basis of their ability to reduce storm surge height in comparison with an unprotected beach. A typical rubble mound breakwater was ineffective against storm surge; however, a rubble mound breakwater retrofitted with a sheet pile core was able to significantly reduce storm surge effects. A vertical breakwater was also tested and found to be effective, especially when retrofitted with a cantilevered deck to reduce overtopping.

Ferolin Jessina, G.; Arasi, R.; Prakash, N.S.; Soumiya, S.; Surya, K.; Mary, S.J.A.J., and Petchimuthu, M., 2025. Combatting waterborne threats: Evaluating antibiotic effectiveness against environmental isolates of Aeromonas hydrophila. Journal of Coastal Research, 41(2), 247–254. Charlotte (North Carolina), ISSN 0749-0208.

The emergence of antibiotic-resistant strains of Aeromonas hydrophila highlights the urgency of understanding the efficacy of conventional antibiotics against environmental isolates. This study investigated the time-kill kinetics of selected antibiotics against A. hydrophila strains isolated from the water of shrimp culture ponds along the Vedaranyam Canal region, Tamil Nadu, India. Identification and characterization of the strains were done through microbiological and molecular techniques. The antibiotics selected for the study included commonly used agents such as ciprofloxacin, gentamicin, ampicillin, oxytetracycline, erythromycin, furazolidone, nitrofurantoin, streptomycin, and tetracycline. The minimum inhibitory concentration (MIC) of antibiotics was determined by the broth macrodilution method. Antibiogram study revealed that the isolates were sensitive to a few antibiotics and showed intermediate resistance to others. The MIC of the antibiotics sensitive against A. hydrophila were obtained. Following the MIC determination, a time-kill kinetic assay was performed at 1× MIC, 2× MIC, and 4× MIC to find the bacteriostatic/bactericidal nature of the test compounds. The results of the study showed a strong bacteriostatic effect of the antibiotics tested against the isolated strains of A. hydrophila. This study provides basic first-line data about the pharmacological activity of the antibiotics. Results indicated that the effectiveness of antibiotics against A. hydrophila isolates varied both in terms of concentration and exposure time. This study contributes valuable insights into the temporal dynamics of antibiotic efficacy against environmental isolates of A. hydrophila.

Joshi, N.; Montero-Serrano, J.-C.; Lefebvre, C., and Saulnier-Talbot, É., 2025. Tracking pre- and post-industrialization changes in the Bay of Sept-Îles, Canada, using foraminifera as bioindicators. Journal of Coastal Research, 41(2), 255–271. Charlotte (North Carolina), ISSN 0749-0208.

A multiproxy analysis of a short sediment core retrieved from the Bay of Sept-Îles (Quebec, Canada) allowed for better understanding of changes in geochemical composition and foraminiferal assemblages during the pre- and post-industrial periods (i.e. before and after 1900 Common Era [CE]). The vertical distribution of the major elements suggests that environmentally consequential colonial activities in Sept-Îles began around the 1860s CE. Elemental analysis showed fluctuations in metal concentrations, with marked shifts in iron, manganese, and calcium levels between the pre- and post-industrial periods. Furthermore, a synchronous shift from calcareous to agglutinated foraminifera suggests a stressful environment for the calcareous species, potentially influenced by factors such as calcium limitation and carbonate dissolution. Species belonging to the genera Reophax and Miliammina and Spiroplectammina biformis showed tolerance of the changing environmental conditions within the bay. Overall, the findings emphasize that none of the element concentrations is above contamination threshold but rather that the shift in the source provenance and escalation in the relative prevalence of metals, especially iron, demands careful consideration because it potentially signifies alterations of environmental conditions. Moreover, the results highlight the sensitivity of foraminifera to environmental changes and their utility as bioindicators of stress in coastal marine ecosystems, providing valuable insights into past and present conditions of the Bay of Sept-Îles and other similar environments.

Lindner, B.L.; Holden, W., and Hannah-Harding, M., 2025. The influence of the Gulf of Mexico on tropical cyclone climatology from Florida to North Carolina. Journal of Coastal Research, 41(2), 272–290. Charlotte (North Carolina), ISSN 0749-0208.

Previous investigations on the climatology of tropical cyclones that impacted Wilmington, North Carolina; Charleston, South Carolina; and Savannah, Georgia, showed that many tropical cyclones approaching from the Gulf of Mexico likely impacted these communities. To test the theories developed in previous investigations to explain the trends observed in the properties of tropical cyclones along the southeastern United States, National Hurricane Center records were used to compile climatologies of tropical cyclones that impacted Jacksonville, Florida, and Cape Canaveral, Florida. Tropical cyclones that impacted Jacksonville had similar properties to those that impacted Wilmington, Charleston, and Savannah. However, tropical cyclones that impacted Cape Canaveral had significant differences to tropical cyclones that impacted the other four cities. Fewer tropical cyclones originated in or passed through the Gulf of Mexico prior to striking Cape Canaveral. The early season secondary maximum in the number of tropical storms that impacted the other four cities was nearly absent in the seasonal pattern of tropical storms that impacted Cape Canaveral. While tropical cyclones that impacted Jacksonville had similar directions of approach and translational velocities to tropical cyclones that impacted Wilmington, Charleston, and Savannah, tropical cyclones that impacted Cape Canaveral had less disparity in translational velocity between tropical storms and hurricanes, and they showed a definite shift to a more southerly direction of approach. Tracks and points of origin for tropical cyclones that impacted Cape Canaveral were also significantly different than suggested by trends observed for the other four cities. However, the climatologies of tropical cyclones that impacted each of the five cities showed evidence of a broadening of the hurricane season in recent decades.

Carvalho, D.G.de; Gaylarde, C.C.; Lourenço, M.F.de P.; Machado, W.T.V., and Baptista Neto, J.A., 2025. Seasonal variations in microplastic pollution in beach sediments along the eastern coast of Rio de Janeiro State, Brazil. Journal of Coastal Research, 41(2), 291–304. Charlotte (North Carolina), ISSN 0749-0208.

Microplastics (MPs) have become a pollutant of intense global concern. Sandy beaches represent fragile ecosystems facing this new threat, since these environments have become deposits for large amounts of plastic waste. Despite this, current knowledge about MP distribution on beaches and the scale of pollution is still lacking, especially in South America. For the first time, the distribution and features of MPs in the sand of 27 beaches along the eastern sector of Rio de Janeiro State shore were studied. MPs were present on all the beaches, but the quantities varied with the season. During the summer, 562 particles were found, whereas in winter, this number exceeded 2987 MP particles. Polymers were identified by attenuated total reflectance–Fourier transform infrared spectroscopy as polyethylene, high-density and low-density polyethylene, polypropylene, polystyrene, and acrylonitrile butadiene styrene. MPs in fragment form comprised almost 50% of the total, with fibers being the next most common form. Calculation of the carbonyl index allows the detection of aging in a selected number of MPs of different polymer types. The summer/winter variation indicated sea and wind forces to be the main determining factors for MP distribution.

Ghosh, S.; Pattanayak, R., and Pulapparambil, A., 2025. Antibacterial efficacy of mangroves: Using bioactive leaf extracts of Avicennia officinalis to combat bacterial diseases in fish. Journal of Coastal Research, 41(2), 305–313. Charlotte (North Carolina), ISSN 0749-0208.

This study examines the practice of using bioactive extracts for fish health promotion and chronic therapy for better production with minimum environmental impact in sewage-fed aquaculture in East Kolkata Wetlands. Avicennia officinalis leaf extract is used as herbal medicine against freshwater fish bacterial disease under culture conditions. Biochemical and morphological identification tests were conducted on infected fishes collected from farmers' fields and farm culture ponds. The antibacterial activity, minimum inhibitory concentration, and disease treatment ability of leaf extracts were tested against three identified fish bacterial pathogens in vitro. The ethyl acetate leaf extract of A. officinalis showed better inhibition activity than other solvents at a concentration of 40 lg/mL against Aeromonas hydrophila and Aeromonas liquefaciens, and 80 lg/mL against Pseudomonas fluorescens in this in vitro assay. The experimental treatment results showed that the herbal feed with 8% leaf extract was more effective than the other two types of tested herbal feed containing 2% and 4% of A. officinalis leaf extract on the infected fishes. This can nurture immunity and decrease fish mortality against the tested bacterial isolates. This in vitro experimental study also showed the effectiveness of ethyl acetate leaf extract of A. officinalis as a feed additive in fish bacterial disease management as a sustainable substitute for synthetic antibiotics under culture conditions.

Al-Attar, I., 2025. Identification of suitable sites for sewage outfalls in Kuwait: A GIS-based coastline case study. Journal of Coastal Research, 41(2), 314–335. Charlotte (North Carolina), ISSN 0749-0208.

This paper applies GIS technology to choose the right places for sewage outfalls in Kuwait Bay, a shallow and comparatively well-sheltered, elliptically formed embayment on the NW segment of the Arabian Gulf. The bay covers 735 km² and has a 130-km coastline. Kuwait Bay gets specific flows, including treated wastewater and partially treated wastewater effluents, besides the stormwaters and hypersaline brine effluent from desalination plants along the coast. Based on the suitability assessment technique, three objectives were selected: water body effluent mixing, sensitive sites existing along the coast, and water quality. These criteria were compiled to prepare the thematic layers for the suitability evaluation index system. The study used the Weighted Overlay model of ArcGIS 10.8 software to assign suitable weights to the thematic layers. The layers were superimposed to produce the suitability site map with two outcomes. First, the coast region is classified into three classes: suitable class, reasonably suitable class, and unsuitable location region class. The second outcome showed that the sewage outfalls had been located ineffectively along the Sulaibikhat Bay coast and Doha. These bays are highly stressed zones and have an inappropriate water-quality index at all the sewage outfalls along the two bays. Therefore, a rehabilitation plan should consider relocating several sewage outfalls after using a water-quality numerical model to check the discharge flow rate required for each outfall along the coast to satisfy Kuwait Environment Public Authority standards.

Kang, B. and Xie, S., 2025. Enhanced tidal intrusion in the Barataria Basin, Mississippi River Delta. Journal of Coastal Research, 41(2), 336–346. Charlotte (North Carolina), ISSN 0749-0208.

Microtidal deltaic systems, comprising a significant portion of global coastal wetlands, are increasingly vulnerable to the combined effects of accelerated sea-level rise and anthropogenic modifications. This study investigates two decades of tidal propagation trends within Louisiana's Barataria Basin, a representative microtidal delta, using wavelet analysis and cross-spectrum techniques applied to a long-term water-level dataset. Results showed a consistent decrease in the predominant (K1) tidal constituent's attenuation, with amplitude ratios at inland stations increasing by as much as 50% between 2008 and 2022. Furthermore, analysis of tidal phase lag variations indicates an increasing trend in K1 tidal wave celerity, suggesting more efficient inland propagation of diurnal tide. This study highlights the rapidly evolving tidal dynamics in microtidal systems and demonstrates the utility of wavelet-based approaches for quantifying these critical changes.

Marenco, R.E. and Canals, M.F., 2025. Numerical modeling of wave transformation in San Juan, Puerto Rico: Comparison between SWAN and SWASH. Journal of Coastal Research, 41(2), 347–365. Charlotte (North Carolina), ISSN 0749-0208.

This study compares SWAN and SWASH results in a realistic two-dimensional scenario to describe wave transformation over a reef environment in San Juan, Puerto Rico. Both models were evaluated with U.S. Geological Survey observations between November 2018 and April 2019. SWAN resolves wave transformation using spectra, including the wind field, white-capping, wave breaking, and bottom friction. SWASH predicts wave propagation with high resolution and different vertical layer configurations, accounting for wave breaking through shock-capturing mechanisms. SWAN was run with an 8 m spatial resolution and forced with buoy wind and wave data, showing very good results across a range of sea states. The SWASH model was run for 20 representative sea states and compared with SWAN. SWASH was also run at 8 m horizontal resolution and was forced with wave buoy data. It was run using three vertical configurations: one layer, two layers, and three layers. A notable improvement in performance was observed when transitioning from a one-layer to a two-layer configuration; however, additional increases in layer count to three layers did not deliver significant benefits. In general, SWAN demonstrated superior performance in predicting wave heights across the examined area for most sea states, except for longer wave periods (>11 seconds), where SWASH showed marginally better accuracy. This pattern shows the robustness of SWAN's phase-averaged methodology under a diverse array of wave conditions. The results also shed light on the significant computational trade-offs between the computationally efficient, phase-averaged SWAN model and the more resource-intensive, phase-resolving SWASH model. Despite SWASH's sophisticated physics, its heightened computational demands did not uniformly result in superior performance, especially for shorter wave periods. SWASH's performance was comparable to SWAN for lower frequency events, but its poor performance in shorter wave periods may have been affected by the limitation of the 8 m spatial resolution.

Muthupandi, K.; Naganandhini, V.; Vasanth, K.; Neethiselvan, N.; Padmavathy, P., and Radhakrishnan, K., 2025. Optimization of the J hook number on the catching efficiency of Carangids in the Gulf of Mannar, India. Journal of Coastal Research, 41(2), 366–372. Charlotte (North Carolina), ISSN 0749-0208.

The efficiency of different J hook numbers 7, 8, and 9 in carangid longline fishing gear was studied from January to August 2022. As revealed through the hooking rate, the highest percentage of contribution in terms of number was observed for Alectis indicus (35.6%), Caranx ignobilis (23.3%), C. hippos (17.0%), Scomberoides commersonnianus (13.8%), and Megalaspis cordyla (10.3%). However, an increased percentage contribution when the catch composition was expressed as the basis of weight instead of number for C. ignobilis (35.2%) was dominant, followed by A. indicus (33.7%), C. hippos (11.5%), S. commersonnianus (10.9%), and M. cordyla (8.7%). The result showed that when using hook number 8, the highest percentage compositions of the carangids was 41% followed by hook number 9 and hook number 7, which were 33.4% and 25.6%, respectively, in terms of number basis; the hook size influenced the catch rate of carangids and body weight (p < 0.05). Further, in terms of weight basis, hook number 8 ranked first (43.5%) among the three hook numbers. Considering catch rates, the overall catch per unit effort (individual/1000 hooks) of hook number 8 was 4.31 higher than that of hook numbers 7 and 9. Among the three hook numbers, the overall performance of hook number 8 was found to be better than that of numbers 7 and 9 in terms of higher catch efficiency and catch per unit effort for carangids.