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Salt marshes are changing due to natural and anthropogenic stressors such as sea level rise, nutrient enrichment, herbivory, storm surge, and coastal development. This study analyzes salt marsh change at Fire Island National Seashore (FIIS), a nationally protected area, using object-based image analysis (OBIA) to classify a combination of data from Worldview-2 and Worldview-3 satellites, topobathymetric Light Detection and Ranging (LiDAR), and National Agricultural Imagery Program (NAIP) aerial imageries acquired from 1994 to 2017. The salt marsh classification was trained and tested with vegetation plot data. In October 2012, Hurricane Sandy caused extensive overwash and breached a section of the island. This study quantified the continuing effects of the breach on the surrounding salt marsh. The tidal inundation at the time of image acquisition was analyzed using a topobathymetric LiDAR-derived Digital Elevation Model (DEM) to create a bathtub model at the target tidal stage. The study revealed geospatial distribution and rates of change within the salt marsh interior and the salt marsh edge. The Worldview-2/Worldview-3 imagery classification was able to classify the salt marsh environments accurately and achieved an overall accuracy of 92.75%. Following the breach caused by Hurricane Sandy, bayside salt marsh edge was found to be eroding more rapidly (F1, 1597 = 206.06, p < 0.001). However, the interior panne/pool expansion rates were not affected by the breach. The salt marsh pannes and pools were more likely to revegetate if they had a hydrological connection to a mosquito ditch (χ2 = 28.049, p < 0.001). The study confirmed that the NAIP data were adequate for determining rates of salt marsh change with high accuracy. The cost and revisit time of NAIP imagery creates an ideal open data source for high spatial resolution monitoring and change analysis of salt marsh environments.

In 2012, Hurricane Sandy created a new tidal inlet at Fire Island National Seashore (FIIS) in New York, USA, consequently altering environmental conditions within Great South Bay. This event presented a unique opportunity to establish new ecological baselines, assess resulting ecological change, and explore management implications. This study focuses on benthic mapping within the bayside of FIIS using acoustic, grab sample, and imagery data. Biotope (habitat) maps were developed describing relationships between macrofaunal communities and their environment. Additionally, biotopes were prioritized by “ecological value” based on user-defined criteria (presence of seagrass and potential for higher trophic level interactions) to guide management. While there are limited pre-Sandy data for comparison, findings from this study suggest the inlet has been a positive ecological influence on the nearby area. Dense concentrations of mature blue mussels (Mytilus edulis) documented near the inlet are considered ecologically beneficial and represent a post-Sandy distinction in ecosystem structure; M. edulis was last common when the inlet was previously open (early 1800s). The inlet is also likely responsible for seagrass expansion near the inlet but decline in other areas. This study advances the utility of the Coastal and Marine Ecological Classification Standard (CMECS) by including CMECS-defined data in analyses and expanding the definition of “dominance.” CMECS played a key role in developing map units, interpreting biotopes, and establishing statistically significant and ecologically meaningful biotic–abiotic relationships. This study also highlights the value and management applications of benthic mapping specific to FIIS and more broadly and advocates for similar studies elsewhere.

Invasive plants may compete with native plants by increasing the pressure of native consumers, a mechanism known as \"apparent competition.\" Apparent competition can be as strong as or stronger than direct competition, but the role of apparent competition has rarely been examined in biological invasions. We used four years of demographic data and seed-removal experiments to determine if introduced grasses caused elevated levels of seed consumption on native plant species in a coastal dune system in California, USA. We show that the endangered, coastal dune plant Lupinus tidestromii experiences high levels of pre-dispersal seed consumption by the native rodent Peromyscus maniculatus due to its proximity to the invasive grass, Ammophila arenaria . We use stage-structured, stochastic population models to project that two of three study populations will decline toward extinction under ambient levels of consumption. For one of these declining populations, a relatively small decrease in consumption pressure should allow for persistence. We show that apparent competition with an invasive species significantly decreases the population growth rate and persistence of a native species. We expect that apparent competition is an important mechanism in other ecosystems because invasive plants often change habitat structure and plant-consumer interactions. Possible implications of the apparent-competition mechanism include selective extinction of species preferred by seed consumers in the presence of an invasive species and biological homogenization of communities toward non-preferred native plant species.

In May 2012, the National Park Service (NPS) asked the National Research Council to conduct a scientific review of a Draft Environmental Impact Statement (DEIS) to evaluate the effects of issuing a Special Use Permit for the commercial shellfish operation in Drakes Estero for a ten year time span. Drakes Bay Oyster Company (DBOC) currently operates the shellfish farm in Drakes Estero, part of Point Reyes National Seashore, under a reservation of use and occupancy that will expire on November 30, 2012 if a new Special Use Permit is not issued. Congress granted the Secretary of the Interior the discretionary authority to issue a new ten year Special Use Permit in 2009; hence, the Secretary now has the option to proceed with or delay the conversion of Drakes Estero to wilderness. To inform this decision, the NPS drafted an Environmental Impact Statement (EIS) for the DBOC Special Use Permit. Under the National Environmental policy Act (NEPA), as EIS is prepared to inform the public and agency decision-makers regarding the potential environmental impacts of a proposed federal action and reasonable alternatives. The Department of the Interior commissioned a peer review of the DEIS that was released in March 2012. Scientific Review of the Draft Environmental Impact Statement: Drakes Bay Oyster Company Special Use Permit reviews the scientific information presented in the DEIS that is used to determine the potential environmental impacts of a ten year extension of DBOC operations. In particular, this report responds to the following tasks given to the committee: assess the scientific information, analysis, and conclusions presented in the DEIS for Drakes Bay Oyster Company Special Use Permit, and evaluate whether the peer review of the DEIS is fundamentally sound and materially sufficient. Scientific Review of the Draft Environmental Impact Statement: Drakes Bay Oyster Company Special Use Permit focuses on eight of twelve resource categories considered in the DEIS: wetlands, eelgrass, wildlife and wildlife habitat, special-status species, coastal flood zones, soundscapes, water quality, and socioeconomic resources.

When Drakes Estero, which lies within the Point Reyes National Seashore (PRNS) about 25 miles northwest of San Francisco, California, was designated by Congress in 1976 as Potential Wilderness, it contained a commercial shellfish mariculture operation. Oyster mariculture began in Drakes Estero with the introduction of the nonnative Pacific oyster in 1932, and has been conducted continuously from that date forward. Hence, the cultural history of oyster farming predates the designation of Point Reyes as a National Seashore in 1962. Nevertheless, with the approach of the 2012 expiration date of the current National Park Service (NPS) Reservation of Use and Occupancy (RUO) and Special Use Permit (SUP) that allows Drakes Bay Oyster Company (DBOC) to operate within the estero, NPS has expressed concern over the scope and intensity of impacts of the shellfish culture operations on the estero's ecosystem. Public debate over whether scientific information justifies closing the oyster farm led to the request for this study to help clarify the scientific issues raised with regard to the shellfish mariculture activities in Drakes Estero.

Organo-mineral and organo-metal associations play an important role in the retention and accumulation of soil organic carbon (SOC). Recent studies have demonstrated a positive correlation between calcium (Ca) and SOC content in a range of soil types. However, most of these studies have focused on soils that contain calcium carbonate (pH > 6). To assess the importance of Ca-SOC associations in lower pH soils, we investigated their physical and chemical interaction in the grassland soils of Point Reyes National Seashore (CA, USA) at a range of spatial scales. Multivariate analyses of our bulk soil characterisation dataset showed a strong correlation between exchangeable Ca (CaExch; 5–8.3 c.molc kg−1) and SOC (0.6–4%) content. Additionally, linear combination fitting (LCF) of bulk Ca K-edge X-ray absorption near-edge structure (XANES) spectra revealed that Ca was predominantly associated with organic carbon across all samples. Scanning transmission X-ray microscopy near-edge X-ray absorption fine structure spectroscopy (STXM C/Ca NEXAFS) showed that Ca had a strong spatial correlation with C at the microscale. The STXM C NEXAFS K-edge spectra indicated that SOC had a higher abundance of aromatic/olefinic and phenolic C functional groups when associated with Ca, relative to C associated with Fe. In regions of high Ca-C association, the STXM C NEXAFS spectra were similar to the spectrum from lignin, with moderate changes in peak intensities and positions that are consistent with oxidative C transformation. Through this association, Ca thus seems to be preferentially associated with plant-like organic matter that has undergone some oxidative transformation, at depth in acidic grassland soils of California. Our study highlights the importance of Ca-SOC complexation in acidic grassland soils and provides a conceptual model of its contribution to SOC preservation, a research area that has previously been unexplored.

Current understanding of sea turtle nesting, hatching, and emergence events has been largely limited to observable events on the surface of the sand, though recent approaches using audio or visual equipment have allowed scientists to better understand some underground nest phenomena. We used a technology-based approach to define motion-related Caretta caretta hatching and emergence nest events. We describe a novel low-cost, accelerometer-based system called TurtleSense that can detect movement and temperature within sea turtle nests remotely. TurtleSense is successfully able to specifically detect motion within sea turtle nests over the entire course of incubation. This system allows for the identification of infertile nests and the detection of four predictable sequential developmental activity patterns in viable nests, including a hatch and posthatch period, the timing of which can be used to tightly predict hatchling emergence events almost to the day. TurtleSense provides a much better understanding about what is happening in the nest before emergence and allows for the generation of a theory of the mechanism that triggers mass emergence. Our results suggest that motion plays a large role in hatchling communication and that the timing of emergence events may be related to the cessation of movement within the nest. Current management of sea turtle nesting events is primarily driven by counting the number of days since the nest was laid, with further safeguards placed at the nest upon subsequent visual observation of depression or emergence events. Use of TurtleSense technology can impact nest management and conservation efforts, allowing organizations to use this motion data to more tightly predict emergence dates for sea turtle hatchlings and to use viability data to inform nest management decisions.

Determining space use for species is fundamental to understanding their ecology, and tracking animals can reveal insights into their spatial ecology on home ranges and territories. Recent technological advances have led to GPS-tracking devices light enough for birds as small as ~30 g, creating novel opportunities to remotely monitor fine-scale movements and space use for these smaller species. We tested whether miniaturized GPS tags can allow us to understand space use of migratory birds away from their capture sites and sought to understand both pre-breeding space use as well as territory and habitat use on the breeding grounds. We used GPS tags to characterize home ranges on the breeding grounds for a migratory songbird with limited available breeding information, the Golden-crowned Sparrow ( Zonotrichia atricapilla ). Using GPS points from 23 individuals across 26 tags (three birds tagged twice), we found home ranges in Alaska and British Columbia were on average 44.1 ha (95% kernel density estimate). In addition, estimates of territory sizes based on field observations (mean 2.1 ha, 95% minimum convex polygon [MCP]) were three times smaller than 95% MCPs created using GPS tags (mean 6.5 ha). Home ranges included a variety of land cover classes, with shrubland particularly dominant (64–100% of home range cover for all but one bird). Three birds tracked twice returned to the same breeding area each year, supporting high breeding site fidelity for this species. We found reverse spring migration for five birds that flew up to 154 km past breeding destinations before returning. GPS-tracking technology allowed for critical ecological insights into this migratory species that breeds in very remote locations.

In 1945, at the end of the most destructive conflict in human history, the United Nations Educational, Scientific, and Cultural Organization (UNESCO) was established, mindful that \"ignorance of each other's ways and lives has been a common cause, throughout the history of mankind, of that suspicion and mistrust between the peoples of the world through which their differences have all too often broken into war.\" In 1968 a vision emerged that conserving the world's ecological resources, and the genetic material they contain, could fundamentally help to sustain the \"defenses of peace.\" Here we describe the value that international communication has had for the science and practice of protecting the world's most precious places, natural and cultural, and the central place of UNESCO in this history. Large portions of the article are presented in the form of a memoir by Tom Gilbert of his involvement with UNESCO's Man and the Biosphere Program, which goes back more than 50 years. Ideas discussed during the 1968 Paris UNESCO Intergovernmental Conference for Rational Use and Conservation of the Biosphere led to the birth of MAB, establishing \"a scientific basis for enhancing the relationship between people and their environments\" and a world network of biosphere reserves as a means to keep options open for the future. Nurturing synergy among groups with common goals in the international resource protection and geoheritage communities is as critical as ever, and in closing we both draw on our own experiences to propose that the United Nations Association of the United States of America (UNA-USA) could bring many groups and individuals together in support of this cause.

Our aim was to develop a method for estimating the number of animals using a single site in an asynchronous species, meaning that not all animals are present at once so that no one count captures the entire population. This is a common problem in seasonal breeders, and in northern elephant seals, we have a model for quantifying asynchrony at the Año Nuevo colony. Here we test the model at several additional colonies having many years of observations and demonstrate how it can account for animals not present on any one day. This leads to correction factors that yield total population from any single count throughout a season. At seven colonies in California for which we had many years of counts of northern elephant seals, we found that female arrival date varied < 2 days between years within sites and by < 5 days between sites. As a result, the correction factor for any one day was consistent, and at each colony, multiplying a female count between 26 and 30 Jan by 1.15 yielded an estimate of total population size that minimized error. This provides a method for estimating the female population size at colonies not yet studied. Our method can produce population estimates with minimal expenditure of time and resources and will be applicable to many seasonal species with asynchronous breeding phenology, particularly colonial birds and other pinnipeds. In elephant seals, it will facilitate monitoring the population over its entire range.