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At least 361 records · Page 20Linked to original sources
USGS2024

Demography with drones: Detecting growth and survival of shrubs with unoccupied aerial systems

Large-scale disturbances, such as megafires, motivate restoration at equally large extents. Measuring the survival and growth of individual plants plays a key role in current efforts to monitor restoration success. However, the scale of modern restoration (e.g., >10,000 ha) challenges measurements of demographic rates with field data. In this study, we demonstrate how unoccupied aerial system (UAS) flights can provide an efficient solution to the tradeoff of precision and spatial extent in detecting demographic rates from the air. We flew two, sequential UAS flights at two sagebrush ( Artemisia tridentata ) common gardens to measure the survival and growth of individual plants. The accuracy of Bayesian-optimized segmentation of individual shrub canopies was high (73–95%, depending on the year and site), and remotely sensed survival estimates were within 10% of ground-truthed survival censuses. Stand age structure affected remotely sensed estimates of growth; growth was overestimated relative to field-based estimates by 57% in the first garden with older stands, but agreement was high in the second garden with younger stands. Further, younger stands (similar to those just after disturbance) with shorter, smaller plants were sometimes confused with other shrub species and bunchgrasses, demonstrating a need for integrating spectral classification approaches that are increasingly available on affordable UAS platforms. The older stand had several merged canopies, which led to an underestimation of abundance but did not bias remotely sensed survival estimates. Advances in segmentation and UAS structure from motion photogrammetry will enable demographic rate measurements at management-relevant extents.

Restoration Ecology↗
USGS2024

Beaver dam analogs did not improve beaver translocation outcomes in a desert river

Stream restoration programs employ beaver-related restoration techniques, including beaver translocations and installation of beaver dam analogs (BDA), to create complex in-stream habitat. We investigated whether BDA installations improved the probability of translocated beavers surviving and colonizing a section of a degraded desert river. We translocated beavers fitted with tracking devices to the Price River, Utah, United States, for 2 years before and after BDAs were installed. We monitored survival and site fidelity of beavers to estimate apparent survival ( φ ), using model selection to evaluate models with BDA, flow, and other factors hypothesized to relate to apparent survival. We found similar apparent survival 8 weeks post-release of pre-BDA ( φ = 0.50 ± 0.08 SE) and post-BDA beavers ( φ = 0.41 ± 0.06 SE). There were 15 predator-caused mortalities and 39 beavers emigrated out of the study site. Top models indicated apparent survival was negatively related to mean flow. Of the 70 BDAs constructed, beaver activity was detected on only two structures and the number of intact natural dams decreased due to monsoon floods. Our results suggest BDAs may not improve survival and site fidelity of translocated beavers in desert river systems. Instead, the dynamic flow of desert rivers and negative relationship between flow and apparent survival suggest the timing of release may be an important consideration for successful beaver translocation. Additional research is needed to understand how habitat, food availability, individual behavior, and resident conspecifics influence beaver translocation success.

Utah↗
USGS2024

Inoculated biocrust cover and functions diverged over a gradient of soil textures and water availability

Restoring biological crust (biocrust) in disturbed drylands is challenging due to the difficult environmental conditions, such as limited soil moisture, low soil nutrients, and extreme temperatures, that impede growth. Understanding how the key components of biocrust—mosses, lichens, and cyanobacteria—react to different environmental factors informs the optimal timing, locations, and species composition for biocrust reintroduction, thereby increasing the likelihood of establishment. Here, we inoculated soils with a diverse range of biocrust organisms, analogous to seeding an area with diverse vascular plant seeds, and varied environmental conditions to observe how these changes influenced the development and functions of reintroduced biocrust. We found that by manipulating soil texture and time spent wet, we can change the proportional cover of biocrust within a restoration-like setting. Specifically, we found that 4 months after inoculation, finer textured soils that received more water become dominated by moss cover, while coarser textured soils with less water remained dominated by cyanobacteria cover, and the interactions between texture and time spent wet strongly influenced cover. We found biocrust morphological group cover had a small, but detectable, effect on ecosystem functions (soil stability and nitrogenase activity, a proxy for nitrogen fixation), but that environmental conditions had a stronger impact on the functions we measured. Manipulative experiments in controlled environments, like this one, can help elucidate the mechanisms underlying the establishment rate and patterns of biocrusts post-inoculation, and inform implementation of inoculations in the field.

New Mexico↗
USGS2024

Nontarget effects of pre-emergent herbicides and a bioherbicide on soil resources, processes, and communities

Community-type conversions, such as replacement of perennials by exotic annual grasses in semiarid desert communities, are occurring due to plant invasions that often create positive plant–soil feedbacks, which favor invaders and make restoration of native perennials difficult. Exotic annual grass control measures, such as pre-emergent herbicides, can also alter soil ecosystems directly or indirectly (i.e. via the plant community), yet there are few studies on the topic in natural, non-cropped landscapes. We asked how spray treatments applied to soil post-fire with the intention of inhibiting invasive annual grasses (such as Bromus tectorum L.) and releasing existing native perennial grasses affected soil resources, a microbial process, and invertebrates in three climatically varied sagebrush steppe sites. Spray treatments included chemical herbicides (imazapic and rimsulfuron) that strongly affected plant communities and a bioherbicide ( Pseudomonas fluorescens strain D7) that did not. Chemical herbicides increased soil mineral nitrogen in proportion to their negative effects on plant cover for 2 years after treatments in all sites and increased soil water and net N mineralization (measured at one site) but did not affect total carbon, nitrogen, or organic matter. Invertebrate responses to herbicides varied by site, and invertebrates increased with chemical herbicides at the highest, wettest site. We show that herbicide treatments can exacerbate pulses of mineral nutrients, which previous studies have shown can weaken ecosystem resistance to invasion. Thus, restoration strategies that increase the likelihood that desired plants can capture mineralized nutrients after herbicide application will likely be more successful.

Restoration Ecology↗
USGS2024

Low rate of population establishment of a freshwater invertebrate (Gammarus lacustris) in experimental conservation translocations

Conservation translocations may be a useful tool for the restoration of declining freshwater invertebrates, but they are poorly represented in the literature. We conducted a before-after/control-impact (BACI) experiment to test the efficacy of conservation translocation for re-establishing abundant populations of the amphipod Gammarus lacustris , a declining species and wildlife food resource in depressional wetlands in the upper Midwest of the United States of America. Each study site ( n = 19) contained at least one treatment wetland receiving translocated G. lacustris from a local donor and one control wetland. We selected study wetlands based on a suite of wetland characteristics and randomly assigned recipient versus control treatment. Gammarus lacustris was detected post-translocation at only 2 of 22 recipient wetlands (1 of 19 sites). Overall, there was a statistical increase in G. lacustris density in recipient wetlands compared to controls; however, the results were of minimal biological significance due to being driven by a single site with low G. lacustris densities. Accordingly, our results suggest that future conservation translocations of amphipods might be successful if limited to recently restored wetlands or informed by a more complex habitat suitability model to differentiate dispersal limitations from habitat limitations. To develop such a model would involve identifying the fewest, most influential physical and biological factors (e.g. wetland size/structure, fish, aquatic vegetation, and water chemistry) from the numerous inter-related factors that correlate with the abundance of naturally occurring G. lacustris ; candidate wetlands to receive amphipods would be those for which the model predicts abundant G. lacustris but in which they do not presently occur.

Minnesota↗
USGS2024

Effect of water delivery and irrigation for riparian restoration in the Colorado River Delta, Mexico

Along Mexico's arid Colorado River Delta, the riparian corridor lacks water due to a reduction in frequent flows, climate change, human infrastructure, and altered riparian landcover from disturbances to invasive species, fire, and high soil and water salinities, which have led to declines in riparian plant health in recent decades. Restoration efforts focusing on small plots have successfully revitalized habitat, which is the motivation for this research. Accurate estimations of water use by riparian vegetation are crucial in arid environments, where measuring actual evapotranspiration (ETa) poses a significant challenge in these narrow corridors. This study utilizes field-validated remote sensing techniques to quantify ETa at restoration sites. Our methods are twofold; we use the Landsat-8 two-band Enhanced Vegetation Index (EVI2) to monitor changes in vegetation greenness—a proxy of plant health—and we integrate EVI2 with potential evapotranspiration (ET) to calculate ETa. Our findings reveal a notable increase in vegetation greenness within the restoration sites over 9 years, with an average increase of 41.3%. Conversely, greenness in adjacent, unrestored control areas declined by 27.3%. The study also indicates a 22.1% increase in ETa in the restored areas, compared to a 30.8% reduction in the unrestored regions. Restored sites in reach 4 experienced ETa increases ranging from 9.2 to 12.2%, whereas their unrestored counterparts show a decline of 21.4%. Valuable estimates are provided of riparian greenness and water use that may assist natural resource managers who are tasked with allocating water and managing habitats within similar riparian corridors.

Colorado River Delta↗
USGS2024

Estimating the benefits of floodplain restoration to juvenile Chinook salmon in the upper San Francisco Estuary, United States, under future climate scenarios

Many river systems within the Central Valley of California have been disconnected from their floodplains, hypothesized to be partially responsible for declining Chinook salmon populations ( Oncorhynchus tshawytscha ). The primary floodplain of the system, Yolo By-Pass (known regionally as “Yolo Bypass”), offered an opportunity to examine whether improved connectivity between the floodplain and river could limit negative climate change effects on salmon populations. Specifically, the top of the floodplain (Fremont Weir) is being modified to provide Sacramento River Chinook salmon better access to floodplain rearing habitat. We estimated restoration effects on the Yolo By-Pass flood regime now and under future climate scenarios using flow rating curves. Additionally, we used temperature and flow-specific effects on Chinook salmon population dynamics within the Yolo By-Pass and Sacramento River complex to describe how the restoration project and climate change may interact to affect juvenile Chinook salmon biomass production. Our results indicate that the Fremont Weir restoration project will extend the frequency, timing, and duration of Yolo By-Pass flooding. Our production model indicates that the modification will result in greater salmon entrainment rates into the Yolo By-Pass, where salmon growth rates, survival rates, and biomass production were higher when compared to the Sacramento River main stem. The project appears to benefit all regional runs of Chinook salmon, which should help support life history diversity. Our results suggest that the weir modification should benefit native fish from the Central Valley that use floodplain habitat and that these benefits may be resilient to challenges created by a changing climate.

California↗
USGS2024

Current and future potential net greenhouse gas sinks of existing, converted, and restored marsh and mangrove forest habitats

Marsh and mangrove forest habitats are productive at capturing and storing carbon, thus actions to protect and create coastal blue carbon sinks could help mitigate global warming. Dredged material is often used to create coastal habitats and evaluating the carbon impact of placement alternatives (PA) could help inform restoration and climate policies. Output from a Delft3D-FM morphodynamics and hydrodynamics model informed a Coastal Wetlands Carbon Model at years 2020, 2025, 2030, and 2050. Three model simulations were used and included (1) no restoration (PA1), (2) restoration dominated with mangroves (PA2), and (3) restoration dominated with marshes (PA3) at a different location. Habitats of brackish marsh, saline marsh, mangrove forest, and saline open water that surround Port Fourchon, Louisiana, U.S.A., were evaluated to estimate the net greenhouse gas (GHG) flux of the study area with and without restoration. In years 2020 and 2025, the study area was estimated to be a net GHG sink (−1.1 ± 0.2 MMT CO 2 e) with or without mangrove and marsh-dominated restoration. At years 2030 and 2050, even with habitat loss due to sea-level rise, the study area for all simulations was projected to remain a net GHG sink. At year 2050, +0.1 ± 0.04 MMT CO 2 e could be avoided with restoration. At the restoration project scale, mangrove-dominated restoration (PA2) had net GHG sinks (−0.07 to −0.09 MMT CO 2 e) near the marsh-dominated restoration (PA3, −0.09 to −0.13 MMT CO 2 e). Thus, these modeled results could help inform future restoration planning and climate policies.

Louisiana↗
USGS2024

Intraspecific trait variability in wild populations predicts neither variability nor performance in a common garden

Dryland restoration requires plant materials capable of performing well despite difficult growing conditions. Selecting plant materials with higher intraspecific trait variability (ITV) may support successful outcomes by enhancing the performance of those materials in restoration settings. However, maintaining ITV from wild populations is not well understood and requires further investigation if ITV is to be incorporated into native plant materials, which are often developed from wild-collected seed grown in agricultural settings. We used two perennial plant species to explore whether (1) ITV measured at field sites predicts ITV in a common garden, (2) rankings of ITV among populations remain stable over time, and (3) higher levels of ITV promote survival and reproductive effort in a common garden. We measured ITV in specific leaf area and height for Bouteloua curtipendula and Heterotheca villosa at field sites and over 2 years in a common garden, as well as survival and flower production in the common garden. We also calculated climate distance between field sites, where seeds were originally sourced, and the common garden to account for the impact of climatic differences on ITV. We found that (1) ITV measured at field sites did not predict ITV in the common garden, (2) rankings of ITV across populations were inconsistent, and (3) relationships between ITV and performance were rare and differed by species. Our findings indicate that the utility of ITV in wild populations as a predictive tool may be limited.

Restoration Ecology↗
USGS2024

Managing to survive despite the weather: Seeding decisions affecting simulated dryland restoration outcomes

Limited favorable weather windows for post-germination early seedling survival are associated with low restoration success in drylands. We examined whether post-fire seeding decisions could alter early seedling emergence and restoration success across western North American sagebrush ecosystems with a simulation approach. Seedling emergence estimates were based on germination of a specified percentile of sown seeds followed by favorable conditions for seedling development. We asked how three categories of seeding decisions affected emergence: post-fire seeding year, seasonal seeding delay (via seed coating technologies or later seeding timing), or native perennial grass seed source (via differing germination behavior). We also tested potential effects of mean annual precipitation on seeding decision outcomes (interactive effect) and included topographic microclimate and site (random effect) in models. Emergence was highest when the best seed source (of 10) was seeded in the best post-fire year (of 5). High emergence also resulted from seeding in the best post-fire year with an average seed source or seeding with the best source in the first post-fire year. Emergence was higher overall with higher mean precipitation. Seeding decision outcomes were sensitive to annual mean precipitation, with greater differences observed due to decisions at lower precipitation levels. While sensitive to assumptions related to seedling development and germination speed, these results suggest that restoration approaches linked to germination behavior and weather variability could improve restoration success rates in variable drylands like sagebrush ecosystems.

California, Idaho, Nevada, Oregon, Utah↗
USGS2025

Hydrologic variability and plant composition drive relative abundance of marsh birds at created and reference marshes in southeastern Louisiana, U.S.A.

Coastal marsh loss occurs at an alarming pace globally, with extremely high rates along the northern Gulf of Mexico, particularly in Louisiana. In Louisiana, marsh creation projects combat wetland loss; however, biotic responses of vegetation and wildlife receive little to no consideration during and after construction. Habitat characteristics such as hydrologic processes, plant composition, and habitat structure affect the abundance of marsh birds, and understanding these features is important when creating suitable habitat for marsh birds. Our study compared hydrologic characteristics, plant composition, and habitat structure between created ( n = 10) and reference ( n = 9) sites across southeastern Louisiana and determined the relationship of these habitat characteristics to marsh bird relative abundance. We performed bird surveys ( n = 766), including call-back surveys for secretive marsh birds, at all sites across three breeding seasons (2021–2023). We used drone imagery to determine plant composition and used water level recording devices to assess hydrologic characteristics. Our results indicate that hydrologic variation and plant composition are drivers of marsh bird relative abundance regardless of whether a marsh is created or not. While some habitat features differed between created and reference sites, our results indicated that created marshes can support similar abundances of marsh birds as reference sites, depending on what habitat features are present at the site. Our study demonstrates the importance of creating marshes that promote hydrologic connectivity and water level variability, which in turn supports diverse emergent vegetation communities and provides suitable habitat for a variety of marsh bird species.

Louisiana↗
USGS2025

Low genetic differentiation across restored and natural populations shortly after a large-scale, post-fire seeding in the Great Basin

Genetic diversity is essential for species to adapt to environmental changes. In restoration efforts, such as those after large wildfires in the sagebrush steppe of the Great Basin, commercially produced native seeds are used to revegetate the burned areas. While native seed certification and procurement protocols assure that genetically appropriate seeds are used for restoration, how post-fire seeding affects the genetic integrity of wildland populations at the landscape scale is unknown. To assess the effects of seeding on the genetic diversity of wildland populations, we conducted a genetic survey of Bluebunch wheatgrass ( Pseudoroegneria spicata [Pursh] Á.Löve ssp. Spicata ) populations within the perimeter of a recent megafire in southeastern Oregon and southwestern Idaho, United States. We genotyped 760 samples with 10 polymorphic loci. We found similar genetic diversity in populations four to 5 years after seeding compared to unseeded populations that were either burned or unburned. Furthermore, genetic diversity neither increased nor decreased with distance from the fire's edge, suggesting that wind dispersal from neighboring remnant populations plays a minor role in immediate post-fire recovery compared to resprouting and germination from the seed bank. Though no change was detected in the short term, this survey of genetic variation after a post-fire seeding provides an empirical baseline that can be used to track changes in genetic diversity of these wildland populations over time.

Idaho↗
USGS2025

Optimizing the effectiveness of connectivity modifiers to reduce dryland degradation

Dryland degradation from unsustainable land use and increasing aridity often manifests as bare, interconnected areas that facilitate the loss or redistribution of resources (soil, seeds, and nutrients) through wind and run-off. Physical structures like branches and stick bundles, which disrupt these pathways and retain resources, are crucial for rehabilitation and restoration. Connectivity modifiers or ConMods, which are galvanized mesh structures that mimic low stature vegetation, are tools specifically designed to interrupt connected pathways and help reinforce overall site stability. Yet, how to effectively and consistently use ConMods to achieve site stability has not been thoroughly tested. Here, we used the Aeolian EROsion model to investigate the combined effects of ConMod height, porosity, and spacing on simulated horizontal sediment flux, a key indicator of site stability. We assessed ConMod performance as percent reduction in predicted sediment flux versus a bare, unvegetated 10,000 m 2 area for a range of horizontal sediment flux. Additionally, in a field experiment, ConMods increased litter retention by up to 15.6 mm compared to bare ground plots, demonstrating their potential to enhance both soil stabilization and resource retention. These findings underscore the potential of ConMods as flexible, cost-effective tools that interrupt positive feedbacks to degradation and provide measurable benchmarks for restoration success.

Utah↗
USGS2025

Seed coating treatments alter emergence windows of native Intermountain West U.S. grasses under different regimes of water availability

Introduction Seed-based restoration is widely implemented to recover degraded lands but often fails. Seed enhancement technologies may improve outcomes by shifting emergence to target favorable climate windows and serving as a bet-hedging strategy against increasingly variable precipitation patterns. Objectives To test the potential benefit of these technologies, we applied seed coatings designed to accelerate or delay emergence to four native Intermountain West perennial grasses that are commonly used for restoration. Methods We subjected seeds to six different watering regimes in the greenhouse that represented variation in precipitation timing and amount and compared the emergence, growth, and biomass of coated and uncoated seedlings. Results Seed coating designed to accelerate germination strongly increased emergence in species with high dormancy requirements, while seed coating designed to delay germination decreased emergence in species with low dormancy by about half and postponed emergence by up to 15 days. These coatings altered emergence timing regardless of watering regime, suggesting that seed coating could expand emergence windows under variable precipitation regimes. Seedling growth and total biomass were less dependent on seed coating and were more driven by the average amount of soil moisture provisioned to the developing plant. While seed coating designed to accelerate germination increased the emergence of two grass species, growth decreased during late periods of water availability, suggesting a trade-off in seedling performance. Conclusions Our results show promise for seed coatings to shift windows of emergence, but further field testing could improve our understanding of their effects in restoration settings.

western United States↗
USGS2026

A matter of timing: Sagebrush steppe restoration seeding outcomes altered by species responses to warmer spring temperatures and interannual weather variation

Introduction Restoration outcomes in cold desert ecosystems like sagebrush steppe are affected by weather variability, particularly during the spring, a critical time period for seedling establishment. Seedling emergence phenology is also highly variable among species in these ecosystems. Seed-based restoration outcomes are likely affected by the emergence timing of species in seed mixes relative to periods of favorable soil microclimate in the spring. Objectives This study evaluated the effects of higher spring temperatures in different periods, and species differences in seedling emergence and survival, on restoration outcomes. We also tested the indirect effects of warming treatments on outcomes via abundance of cheatgrass, a competitive, widespread invasive annual sensitive to weather variability. Methods We used open-sided chambers to implement early- or late-spring warming on plots seeded with a diverse set of species that differed in timing of emergence, across multiple years and variable weather conditions in sagebrush steppe, Oregon, U.S.A. Results Spring warming treatment effects varied with yearly weather and species emergence timing relative to the rest of the seeded species. Later-emergence timing was associated with lower emergence rates, particularly with late spring warming, and lower survival with early spring warming, but higher survival without warming or with late spring warming. Seed mix scenarios tuned to warming treatment and yearly weather outperformed early- or late-emergence timing and even proportion mixes. Early spring warming increased invasive annual grass abundance, which was associated with lower survival of seeded species. Conclusions Species differences and yearly precipitation affected restoration outcomes under warmer spring temperatures.

Oregon↗
USGS2026

Alternative approaches to dryland reclamation enhance vegetation cover and soil stability at a former uranium mine

Introduction Conventional reclamation methods to recover dryland ecosystems after mineral extraction often have low success. Alternative reclamation techniques may help overcome the many challenges to establishing persistent native vegetation and stable soils. Objectives Compare conventional reclamation approaches that focus primarily on soil stabilization to alternative approaches that may improve native ecosystem restoration at the Kanab North Mine in northern Arizona. Methods In a fully crossed experiment, conventional seed mix (native and non-native species) and seeding methods (drill-seeding) were compared to alternative practices, including a native-only seed mix, connectivity modifiers (ConMods) with hand seeding, and a biocrust inoculation. Restoration metrics like plant establishment, species composition, soil surface cover and stability, biocrust establishment, and near-surface wind-driven sediment were monitored over the first 5 years post-reclamation. Results While all restoration metrics improved with time, compared to traditional methods, ConMods increased total, graminoid, and native plant species cover, and the native-only seed mix increased woody, native, and perennial species cover. Biocrust inoculation increased late-successional biocrust development, but biocrusts only persisted over 5 years in combination with ConMods. Soil stability increased in all treatments, but both ConMods and biocrust inoculation increased stability compared to traditional practices. Conclusion Overall, alternative approaches to reclamation tested here (ConMods, native seed, and biocrust inoculation) were more effective than traditional practices at increasing total plant cover, facilitating biocrust establishment, and promoting soil stability after uranium mine reclamation.

Arizona↗
USGS2026

Can surface treatments and climate matching enhance restoration success in the Sonoran Desert?

Introduction Restoring native plant communities in arid ecosystems through seeding is a critical yet often unsuccessful strategy due to severe environmental stressors, including degraded soils, low and variable rainfall, and seed predation. Objectives To improve restoration outcomes, we examined the influence of seed mix types and soil surface treatments on seeded and unseeded plant establishment across three Sonoran Desert sites, Arizona, United States. Methods Using a factorial design, we tested two seed mix types (cool versus warm adapted species) and four soil surface treatments (pits, mulch, connectivity modifiers or ConMods, and controls) on plant establishment. We examined if patterns of plant establishment could be predicted by whether the climate envelope of species in the seed mix types was similar to the site climate where they were seeded (climate matching). We monitored seeded and unseeded species establishment for 3 years and analyzed these effects using generalized linear mixed models and Tukey-adjusted multiple comparisons. Results Pit treatments significantly enhanced seeded species density by nearly 3× and cover by 2× compared with ConMods and increased unseeded plant density by 2× to 4× times during post-drought springs. During these same seasons, species suited to cooler temperatures (e.g. Salvia columbariae and Lupinus sparsiflorus ) had higher cover at the site receiving the highest precipitation, and species suited to warmer temperatures (e.g. Sphaeralcea ambigua and Senna covesii ) established better at the drier two sites. Conclusions In arid systems, surface treatments like pits that retain soil moisture were most promising for supporting seed-based restoration, and matching species that have high temperature tolerance with hotter, drier sites may enhance restoration success.

Arizona↗
USGS2026

Mesophotic octocoral larval settlement preferences and behaviors

Introduction Lab-based coral reproduction is advancing restoration efforts to support coral populations injured by the 2010 Deepwater Horizon oil spill. Objectives This study aimed to answer foundational questions concerning coral spawning and larval settlement that need to be resolved for these mesophotic and deep-sea coral species before restoration efforts can be scaled up. Methods From 2021 to 2023, fragments of the mesophotic octocorals Swiftia exserta and Thesea nivea were collected from the continental shelf offshore from Texas to Florida and transported to a federal facility in Florida. Multiyear spawning allowed for in-depth analysis of spawning periodicity, egg development, larval behavior, settlement rate, and substrate preference. In addition, we determined the likelihood of successful development and survival during early stages of development. Results Fertilization rates remained high throughout spawning periods of both species, with S. exserta spawning during a 1-month period and T. nivea continuing to spawn year-round. Larvae from both corals significantly preferred tiles seeded with crustose coralline algae, and there were species-specific preferences in substrate material. Additionally, larval survival or mortality was typically evident within a few days when in the presence of settlement substrates. In the absence of substrates, we observed larvae surviving for up to 2 months without settling. Conclusions This work answers critical questions to inform the long-term logistical planning for eventual out-planting of these species. Further, it highlights avenues that could accelerate future restoration-based reproduction efforts into unexplored mesophotic and deep species.

Alabama, Louisiana, Mississippi, Texas↗