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This paper explores how spatial judgments impacted planning and policy-making by studying how stakeholders on Cape Cod, Massachusetts considered cross-scale relationships between local, regional, and state jurisdictions and hydro-geologically defined watersheds. Analysis of video data from participatory planning workshops illustrates how these judgments were made as stakeholders developed a regional wastewater management plan. Detailed analysis of their deliberations illustrates the complex and dynamic nature of their scalar judgements as they addressed mismatches between watersheds and towns. Findings illustrate how their judgments were part of the process that led to the development of innovative policy tools for collective action that embraced, rather than erased, mismatches. This paper also demonstrates the application of spatial judgments of non-expert stakeholders as they made plans and proposed actions for a complex social-ecological system. [ABSTRACT FROM AUTHOR]

The maintenance of wind farms is one of the major factors affecting their profitability. During preventive maintenance, the shutdown of wind turbines causes downtime energy losses. The selection of when and which turbines to maintain can significantly impact the overall downtime energy loss. This paper leverages a wind farm power generation model to calculate downtime energy losses during preventive maintenance for an offshore wind farm. Wake effects are considered to accurately evaluate power output under specific wind conditions. In addition to wind speed and direction, the influence of wake effects is an important factor in selecting time windows for maintenance. To minimize the overall downtime energy loss of an offshore wind farm caused by preventive maintenance, a mixed‐integer nonlinear optimization problem is formulated and solved by the genetic algorithm, which can select the optimal maintenance time windows of each turbine. Weather conditions are imposed as constraints to ensure the safety of maintenance personnel and transportation. Using the climatic data of Cape Cod, Massachusetts, the schedule of preventive maintenance is optimized for a simulated utility‐scale offshore wind farm. The optimized schedule not only reduces the annual downtime energy loss by selecting the maintenance dates when wind speed is low but also decreases the overall influence of wake effects within the farm. The portion of downtime energy loss reduced due to consideration of wake effects each year is up to approximately 0.2% of the annual wind farm energy generation across the case studies—with other stated opportunities for further profitability improvements. [ABSTRACT FROM AUTHOR]

Remote aerial sensing provides a non‐invasive, large geographical‐scale technology for avian monitoring, but the manual processing of images limits its development and applications. Artificial Intelligence (AI) methods can be used to mitigate this manual image processing requirement. The implementation of AI methods, however, has several challenges: (1) imbalanced (i.e., long‐tailed) data distribution, (2) annotation uncertainty in categorization, and (3) dataset discrepancies across different study sites. Here we use aerial imagery data of waterbirds around Cape Cod and Lake Michigan in the United States to examine how these challenges limit avian recognition performance. We review existing solutions and demonstrate as use cases how methods like Label Distribution Aware Marginal Loss with Deferred Re‐Weighting, hierarchical classification, and FixMatch address the three challenges. We also present a new approach to tackle the annotation uncertainty challenge using a Soft‐fine Pseudo‐Label methodology. Finally, we aim with this paper to increase awareness in the ecological remote sensing community of these challenges and bridge the gap between ecological applications and state‐of‐the‐art computer science, thereby opening new doors to future research. [ABSTRACT FROM AUTHOR]

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The cranberry, a commodity of social, cultural, and economic importance to New England, is under threat due to climatic change in this region of the United States. Yet, previous research reveals that cranberry growers have mixed attitudes about the anthropogenic roots of climate change, with many being skeptical. Building on the researchers' analysis of the personal and ecological conditions that affect climate change attitudes among cranberry growers, this paper examines the effect that key actors in the growers' social networks have on those attitudes. Through statistical analysis of survey data and content analysis of two important cranberry newsletters, the paper finds that cranberry growers' perceived importance of two key cranberry growing institutions, the "sociopolitically focused" Cape Cod Cranberry Growers' Association and the "technically focused" University of Massachusetts Cranberry Station, as well as connections to other cranberry growers, is associated in nuanced ways with growers' climate change attitudes. Drawing on the sociological theory of "social capital," the paper examines how these social ties to key actors/institutions may result in greater threat perception or worry about climate change. It then considers how "green ties," if harnessed and supported by these important actors in the cranberry grower network, might significantly mitigate climate change in the future. [ABSTRACT FROM AUTHOR]

Geophysical evidence is presented for the existence of modern and fossil pockmarks within the New England Mud Patch, an anomalous region of fine‐grained deposition on the middle shelf south of Cape Cod, USA. Modern pockmarks, indicators of focused subsurface fluid flow, are observed as seafloor depressions up to 80‐m wide and 1.2‐m deep, with reflective centers evincing hard material. Probable fossil pockmarks are identified by predominantly u‐shaped bright lenses within the sub‐bottom data and have similar size and distribution as the seafloor pockmarks; they likely indicate long‐term (>10 ka) persistence of episodic‐focused fluid flow. Given the lack of seismic evidence for gas, these features are attributed to submarine groundwater discharge. Based on recent observations and modeling, it is suggested that submarine groundwater discharge is induced by salinity‐driven convection cells associated with overpressured fluids, emplaced either by modern, shore‐connected aquifers, or during Pleistocene glacial advances and retreats. Plain Language Summary: Pockmarks are crater‐like features on the seafloor that are typically formed by the escape of either methane gas or groundwater from the sediments beneath the ocean. This paper reports on modern and fossil pockmarks discovered in the New England Mud Patch, on the continental shelf south of Cape Cod, Massachusetts. Finding no acoustic evidence for gas, it is inferred that the pockmarks are formed by groundwater expulsion and have been forming in this region for at least the past 10,000 years. Other studies suggest that freshwater aquifers are widespread under the continental shelf in the Mid‐Atlantic Bight (the region between Cape Hatteras and Cape Cod) and may be feeding fluid escape at the seafloor. If so, then the concentration of pockmarks in the New England Mud Patch is probably due to the strong preservation potential of muddy (not sandy) sediments, rather than a concentration of groundwater discharge in this region. These results could have important implications for global understanding of fluid, nutrient and mineral exchange between the seafloor and the ocean. Key Points: Fossil and modern seabed pockmarks were discovered in the New England Mud Patch, indicating long‐term‐focused fluid flow on the middle shelfWith no evidence for gas in seismic data, pockmarks are interpreted to be sites of submarine groundwater dischargeRecent studies suggest that discharge may be related to salinity‐driven convection associated with overpressured fresh water at depth [ABSTRACT FROM AUTHOR]

Policies and regulations designed to address nutrient pollution in coastal waters are often complicated by delays in environmental and social systems. Social and political inertia may delay the implementation of cleanup projects, and even after the best nutrient pollution management practices are developed and implemented, long groundwater travel times may delay the impact of inland or upstream interventions. These delays and the varying costs of nutrient removal alternatives used to meet water quality goals combine to create a complex dynamic decision problem with tradeoffs about when, where, and how to intervene. We use multi‐objective optimization to quantify the tradeoffs between costs and minimizing the time to meet in‐bay nutrient reduction goals represented as a Total Maximum Daily Load (TMDL). We calculate the impact of using in‐bay (in situ) nutrient removal through shellfish aquaculture relative to waiting for traditional source control to be implemented. We apply these methods to the Three Bays Watershed in Cape Cod, Massachusetts. In gross benefit terms, not accounting for any social costs, this equates to an average value of 37¢ (2035 TMDL target date) and 11¢ (2060 TMDL target date) per animal harvested over the plan implementation period. Our results encourage the consideration of alternative and in situ approaches to tackle coastal pollution while traditional source control is implemented and its effects realized over time. Research Impact Statement: Shellfish are worth between 11‐37¢ per animal harvested when compared to traditional approaches to dealing with nutrient pollution on Cape Cod, MA, USA. The timing of the pollution cleanup matters. [ABSTRACT FROM AUTHOR]

This paper discusses the utility of using seismic-reflection profiling and sediment cores in addition to bottom grab samples and acoustic data to develop shallow-water benthic habitat maps. Currently, the classification system used herein does not provide for the incorporation of stratigraphic data, but we believe that the utility of these maps would improve if such data were included. We conducted vessel-based seafloor-mapping surveys using a phase-measuring sidescan sonar in very shallow waters (mean depth = 3.2 m) covering an area >6.7 km2 in Pleasant Bay in 2014. We collected a total of 192 bottom grab samples to document macro-invertebrates and sediment characteristics. We conducted seismic-reflection profiling surveys to document stratigraphy and determine optimal locations for multiple sediment cores during the 2014 field season; we collected both Kullenberg and Livingstone cores. The seismic-reflection data, though conducted at the reconnaissance scale, proved useful to place the seafloor acoustic data in context. The acoustic and benthic habitat data and mapping products become more valuable when an understanding of the underlying stratigraphy is used as context for the benthic habitat maps. Sediment coring and analysis can provide insights into past and current basin evolution, which can further aid marine natural resource managers. However, we believe that stratigraphic data should be incorporated into standard benthic habitat mapping protocols. These multi-modal datasets provide a better understanding of these habitats for the multidisciplinary teams that typically produce and use these maps as well as coastal managers. [ABSTRACT FROM AUTHOR]

Objective: Atlantic Menhaden Brevoortia tyrannus support fisheries that yield the largest landings by volume on the U.S. East Coast and fulfill a critical ecological role as a forage species. The spawning reference point of the stock assessment model that is routinely applied to this species requires information on total annual fecundity. The goal of this study was to generate a contemporary, histology‐based evaluation of the reproductive biology and fecundity of female Atlantic Menhaden. Methods: Female Atlantic Menhaden (n = 559) were collected between Cape Cod, Massachusetts, and Cape Hatteras, North Carolina, from 2013 to 2019. Ovarian tissues were prepared using standard histological techniques which, when coupled with oocyte size‐frequency and count data, were used to classify reproductive mode and estimate batch fecundity, spawning frequency, and maturity. Monthly gonosomatic indices were combined with published female reproductive information and spatiotemporal patterns in larval and juvenile abundance to designate spawning seasonality. Result: Histological preparations and oocyte size‐frequency patterns of female Atlantic Menhaden ovaries were consistent with indeterminate batch spawning. Batch fecundity increased with fork length, while spawning seasonality extended from September 15 to April 15 with a spawn every 7.5 ± 2.3 days. Female maturity probabilities transitioned from 0.2 to 0.8 over fork lengths of 214.8–226.5 mm (approximately ages 2.0–2.3 years). Estimated mean per capita female annual fecundity varied from 465,757 to 3,250,135 oocytes for fish ranging from 215.8 to 284.8 mm fork length (ages 2–6 years), which represented a 614–2267% (mean = 1656%) increase in annual female reproductive output relative to previous estimates. Conclusion: Female Atlantic Menhaden exhibit indeterminant batch spawning while spawning seasonality and mean per capita female annual fecundity were appreciably greater than previously reported. This new reproductive information illuminates the robust reproductive productivity of this species and will aid routinely conducted stock assessments. Impact statementFemale Atlantic Menhaden reproductive biology was re‐evaluated and egg productivity is much greater than previously understood. This high productivity likely explains how this species annually supports substantial commercial removals and high predation demands by many fishes, marine mammals, and sea birds. [ABSTRACT FROM AUTHOR]

Abstract Breaching of coastal barriers, leading to the formation of ephemeral or permanent inlets, is an essential element of coastal evolution in many parts of the world. With time, some inlets migrate or close, leaving no surface signature of their existence. The challenge of locating these channels through coring is exacerbated by high gravel content and widespread anthropogenic development. Subsurface imaging using ground-penetrating radar (GPR) is often the only viable technique to overcome this limitation. GPR surveys carried out across microtidal baymouth barriers fronting salt ponds on Cape Cod, Massachusetts reveal a series of paleo-channels that lack any geomorphic expression. In some areas, channel fill comprises 50–80% of the barrier lithosome. The pre-closure dimensions of historic channels identified on charts and photographs spanning the past 170 years were measured in these subsurface records. In addition, records revealed eight previously unknown relict channel structures with widths (W) ranging between 25 and 100 m and depths (D) of 1–4 m. Based on minimum cross-sectional dimensions in GPR images, a W/D ratio of ~40 is characteristic of the natural (unstabilized) paleo-channels. This study demonstrates that the distribution and morphometry of buried channels based on high-resolution geophysical images can be used to reconstruct past equilibrium hydrodynamic conditions, with implications for locating important alongshore anomalies and assessing coastal vulnerability to breaching. Highlights • This paper presents a comprehensive georadar investigation of buried coastal channels along a formerly glaciated coastline. • Due to coarse-grained nature and widespread anthropogenic structures, traditional geological methods e.g., coring and trenching) are not feasible, making GPR the only viable methodology. • This study not only confirmed the locations of historic inlet channels, but also discovered several unknown features. • Geophysical records allowed quantification of gross channel geometry, with implications for reconstructing hydraulic conditions. [ABSTRACT FROM AUTHOR]

From 2004 to 2014, the Line W moorings measured a 0.7 Sv yr−1 slowing of the deep western boundary current (DWBC) offshore of Cape Cod. Here, we combine these deep mooring observations with float and satellite altimeter data and find that this DWBC change corresponded to a slowing of the cross‐basin Atlantic Meridional Overturning Circulation (AMOC) of about 0.3 Sv yr−1. Our AMOC transport time series corresponds well with the Estimating the Circulation and Climate of the Ocean state estimate, particularly when the Line W mooring data influences our volume closure. We compare our 35°N time series with a similar time series at 41°N as well as the 26°N RAPID AMOC, and find AMOC declines across datasets from 2004 to 2014. However, when we extend our analysis to 2004–2019, there are no significant trends at any latitude. These observations suggest that AMOC decadal variability is meridionally coherent from 26°N to 41°N and that the DWBC may reflect this variability. Plain Language Summary: The Atlantic ocean hosts an overturning circulation that is thought to be an important piece of our climate system. This circulation pattern spans the width of the basin, making it difficult and costly to measure, so direct observations of the overturning circulation are scarce. In this study we combine existing mooring, float, and satellite altimeter observations to estimate the overturning circulation at a new latitude (35°N), and compare it to existing estimates at 26°N and 41°N as well as the ECCO ocean state estimate. We find that the long term (about 10 year) AMOC variability is consistent across latitudes and data products. While we cannot rule out a decreasing AMOC trend during the 20th century, we find that natural variability is too large to detect a net AMOC decrease in direct observations since 2004. Key Points: We compile an Atlantic Meridional Overturning Circulation (AMOC) time series at 35°N from deep moorings, floats, and altimeter that agrees with the Estimating the Circulation and Climate of the Ocean state estimateThe 2004 to 2014 slowing of the deep western boundary current corresponded to an AMOC decline at 35°NWe find no evidence of long‐term AMOC decline, but consistent decadal variability across 26°N, 35°N, and 41°N [ABSTRACT FROM AUTHOR]

Mitigating non‐point source nitrogen in coastal estuaries is economically, environmentally, logistically, and socially challenging. On Cape Cod, Massachusetts, nitrogen management includes both traditional, centralized wastewater treatment and sewering as well as a number of alternative technologies. We conducted semi‐structured interviews with 37 participants from governmental and non‐governmental organizations as well as related industries to identify the barriers and opportunities for the use of alternative technologies to mitigate nitrogen pollution. The interviews were recorded, transcribed, and then analyzed using content analysis and rhetorical analysis. Cost and technical capacity to reduce nitrogen were the most discussed considerations. Beyond those, there were a slew of additional considerations that also impacted whether a technology would be installed, permitted, and socially accepted. These included: maintenance and monitoring logistics, comparisons to sewering, co‐benefits, risk/uncertainty, community culture, extent of public engagement, permitting/regulatory challenges, and siting considerations. The insights about these additional considerations are valuable for transferring to other coastal areas managing nutrient impairments that may have not yet factored in these considerations when making decisions about how to meet water quality goals. [ABSTRACT FROM AUTHOR]

This paper explores historical evolution of blowouts at Cape Cod National Seashore (CCNS), USA — a site that hosts one of the world's highest densities of active and stabilized blowouts. The Spatial–Temporal Analysis of Moving Polygons (STAMP) method is applied to a multi-decadal dataset of aerial photography and LiDAR to extract patterns of two-dimensional movement and morphometric changes in erosional deflation basins and depositional lobes. Blowout development in CCNS is characterized by several geometric (overlap) and movement (proximity) responses, including: i) generation and disappearance, ii) extension and contraction, iii) union or division, iv) clustering and v) divergence by stabilization. Other possible movement events include migration, amalgamation and proximal stabilization, but they were not observed in this study. Generation events were more frequent than disappearance events; the former were highest between 1985 and 1994, while the latter were highest between 2000 and 2005. High rates of areal change in erosional basins occurred between 1998 and 2000 (+ 3932 m 2 a −1 ), the lowest rate (+ 333 m 2 a −1 ) between 2005 and 2009, and the maximum rate (+ 4589 m 2 a −1 ) between 2009 and 2011. Union events occurred mostly in recent years (2000–2012), while only one division was observed earlier (1985–1994). Net areal changes of lobes showed gradual growth from a period of contraction (− 1119 m 2 a −1 ) between 1998 and 2000 to rapid extension (+ 2030 m 2 a −1 ) by 2010, which is roughly concurrent with rapid growth of erosional basins between 2005 and 2009. Blowouts extended radially in this multi-modal wind regime and, despite odd shapes initially, they became simpler in form (more circular) and larger over time. Net extension of erosional basins was toward ESE (109°) while depositional lobes extended SSE (147°). Lobes were aligned with the strongest (winter) sand drift vector although their magnitude of areal extension was only 33% that of the basins. These differences in extension responses likely result from more complex and evolving flow-form interactions inside erosional basins. Historical photographs and CCNS documents suggest that blowout evolution may be influenced by land-use changes, such as revegetation campaigns in 1985 that were followed by high blowout generation. High magnitude regional storm events (e.g., hurricanes) also play a role. The analytical framework presented provides a systematic means for two-dimensional geomorphic change detection and pattern analysis that can be applied to other landscapes. [ABSTRACT FROM AUTHOR]

Solving estuarine water quality problems on Cape Cod, Massachusetts, or elsewhere, is difficult. Nitrogen from septic systems takes years to decades to travel by groundwater to estuaries, depending on local hydrogeology, meaning that nitrogen loading in future years may exceed current conditions. We created a dynamic nitrogen model of Cape Cod's 54 estuaries to better understand 1. how past and present conditions, including legacy nitrogen in groundwater, influence future nitrogen loading, and 2. how different development and nitrogen abatement scenarios could have additional effects. We find that 43 of 54 estuaries are not in equilibrium with current watershed nitrogen loading levels; this increases to 52 of 54 under a buildout scenario. Watersheds contain up to 1000 tons of legacy nitrogen in groundwater; yet, we find that a rapid investment in source control successfully reduces nitrogen loading, revealing a wide range of potential outcomes that depend ultimately on the resources and attention invested in the problem. [ABSTRACT FROM AUTHOR]

Linking human behavior to environmental quality is critical for effective natural resource management. While it is commonly assumed that environmental conditions partially explain variation in visitation to coastal recreation areas across space and time, scarce and inconsistent visitation observations challenge our ability to reveal these connections. With the ubiquity of mobile phone usage, novel sources of digitally derived data are increasingly available at a massive scale. Applications of mobile phone locational data have been effective in research on urban-centric human mobility and transportation, but little work has been conducted on understanding behavioral patterns surrounding dynamic natural resources. We present an application of cell phone locational data to estimate the effects of beach closures, based on measured bacteria threshold exceedances, on visitation to coastal access points. Our results indicate that beach closures on Cape Cod, MA, USA have a significant negative effect on visitation at those beaches with closures, while closures at a sample of coastal access points elsewhere in New England have no detected impact on visitation. Our findings represent geographic mobility patterns for over 7 million unique coastal visits and suggest that closures resulted in approximately 1,800 (0.026%) displaced visits for Cape Cod during the summer season of 2017. We demonstrate the potential for human-mobility data derived from mobile phones to reveal the scale of use and behavior in response to changes in dynamic natural resources. Potential future applications of passively collected geocoded data to human-environmental systems are vast. [ABSTRACT FROM AUTHOR]

Background: Communities in Cape Cod, Massachusetts were exposed to tetrachloroethylene (PCE) through contaminated drinking water from 1969 to 1983. PCE exposure during adulthood has well-established neurotoxic effects; however, long-term impacts stemming from early life exposure, especially adverse effects on sleep quality, are not well understood.Methods: The present analysis was based on data from the Cape Cod Health Study, a retrospective cohort study of the long-term neurotoxic impacts of early-life exposure to PCE-contaminated drinking water. Exposure to PCE-contaminated water was estimated using a validated leaching and transport model. Measures of sleep quality were obtained from self-administered questionnaires. Generalized estimating equations were used to generate risk ratios and 95% confidence intervals to estimate the association between early-life PCE exposure and sleep quality among 604 participants.Results: Compared to unexposed participants, any PCE exposure during early life was associated with 1.57 times the risk of reporting breathing pauses during sleep (95% CI 0.92-2.68). Low-level exposure to PCE was associated with 1.50 times the risk of reporting sleep apnea or other sleep disorders (95% CI 0.78-2.89), while high levels of exposure had comparable risk compared to no exposure (RR = 0.94, 95% CI 0.50-1.79). Weak or no associations were observed for other sleep quality outcomes. In stratified analyses participants with mental illness and/or substance use disorder had increased risk ratios for short sleep duration associated with PCE exposure.Conclusion: These findings suggest that early-life exposure to PCE may be associated with a moderate increase in the risk of reporting breathing pauses during sleep in adulthood and that a history of mental illness and/or substance use disorder may exacerbate the risk of short sleep duration. [ABSTRACT FROM AUTHOR]

SeaLite Engineering, after a 10-yr research and development program, has produced an operational antifouling system for ocean sensors and instruments designed for low power consumption and long (>1 yr) deployments. The important innovation is the replacement of pumps by gravity and external motion to significantly reduce energy consumption. Also, a prototype system for autonomous underwater vehicle control surfaces is now undergoing laboratory testing. The effectiveness of SeaLite's technology has been demonstrated year-round in northern estuaries and in the Gulf of Mexico, the latter by an independent agency. The process leading to this result was, first starting in 2010, an extensive laboratory evaluation of electrode alloys, calibration of chlorine production versus electric power input, and the location for attaching electrodes to various objects requiring protection from fouling. After 2015 the experimentation moved to the ocean, first in a Cape Cod estuary and then to the Gulf of Mexico. Comparisons with a mechanical antifouling system were done in situ, and with a UV antifouling system from AML Oceanographic, Ltd., by comparing the data. Starting in 2019, the development of biofilms, from their initial deposition through the extra polysaccharide substance stage, were experimentally investigated by taking samples from an estuary near SeaLite's laboratory. Biofilms on microscope slides and water column samples were collected. This was done in different seasons, from spring bloom, summer doldrums, autumn temperature decline, and the winter freeze. The objective was to determine the level of biofilm growth that would require antifouling, and its' seasonal, temperature, and solar radiation dependence, and thus to conserve power. [ABSTRACT FROM AUTHOR]

The browntail moth (Euproctis chrysorrhoea (L.)) is a forest pest that was accidentally introduced in the late 1800's and spread throughout New England in the early part of the 20th Century. At its peak range expansion in 1915 it encompassed an area of 150,000 km2 after which populations declined. By the 1960s, its distribution had receded to relic populations on outer Cape Cod, MA, and islands in Casco Bay, ME. In 1989 browntail moth resurged in Maine, with periodic, moderate outbreaks before a dramatic increase of the population occurred in 2016. We examined the pattern of annual defoliation by browntail moth since its resurgence in the 1990s as well as variation in populations throughout infested areas in Maine during three years of the recent outbreak, 2016–2018, relative to differences in weather, parasitism and habitat characteristics. Levels of defoliation over 24 yr were predicted by the preceding spring precipitation (−, negative effect) and the year's previous late summer and early fall temperatures (+, positive effect) when first to third instar larvae feed and then construct winter hibernacula. Late summer temperatures predicted the abundance of hibernacula across outbreak areas (+). Early spring temperatures (+) and early and late spring precipitation (−) predicted early summer larval and pupal nest abundance. Warmer fall temperatures result in more mature populations coming out of winter hibernacula in the spring, whereas spring precipitation drives epizootic outbreaks of Entomophaga aulicae (Reichardt in Bail) Humber (Entomophthorales: Entomophthoraceae). with parasitoids playing a lesser role. Climate trends indicate continued increases in fall temperatures since browntail moth resurgence. [ABSTRACT FROM AUTHOR]

To assess effects of N loads, season, and down-estuary transit on estuarine concentrations of nitrate (NO3), ammonium (NH4), dissolved organic nitrogen (DON), and total dissolved nitrogen (TDN), we sampled three estuaries within Waquoit Bay, MA (USA), subject to different N loads, from spring to fall, at nine stations spanning the salinity range. Conventional statistical analysis on the basis of entire data for the three estuaries suggested significant effects of N loads on concentrations, but comparisons with effect size measures suggested that the effects were minor, largely an artifactual result from the large number of samples. Constraining variation by binning data into weekly means, and partitioning data by season (summer vs. spring-fall) and down-estuary transit (based on salinity) improved interpretations, allowing emergence of detectable increases in NO3 concentrations in estuaries subject to larger N loads, confirmed interactions between N load and season (seasonal increases in NO3 larger in estuaries subject to higher N loads), and down-estuary gradients (highest NO3 concentrations in fresher reaches and significant down-estuary decreases in NO3). NH4 and DON were less responsive to N loads, with rapid uptake of NH4 and seasonal trajectories of DON subject to within-estuary features. TDN concentrations decreased down-estuary, with 13–36% of loss attributable to within-estuary interception, a considerable effect in spite of short water residence times. Management implications include the need to sample seasonally and cover the salinity gradient, checking conventional statistical analyses of pooled data from large databases, using effect size measures to ensure meaningful biological and management results, and attention to the limited lability of DON often included in considering estuarine TDN and N loads. [ABSTRACT FROM AUTHOR]

The American common eider Somateria mollissima dresseri is a sea duck of coastal mid-Atlantic North America, and breeding colonies in the southern part of its range have been in decline. To better understand threats faced by the subspecies, we used satellite telemetry to track 46 eiders through their annual cycle in four years from three regions in the southern part of the range, to identify key locations and migratory corridors. Female eiders exhibited highly variable movement phenology within and among colonies, but coastal Maine and Massachusetts were consistent, important moulting areas for males and females from all breeding colonies. Most birds wintered in coastal waters around Cape Cod and Nantucket Sound, meaning that threats in this region (industrial development, disease outbreak, harvest) could have deleterious effects on much of the population. [ABSTRACT FROM AUTHOR]

Many invasive species may be constrained in their ability to invade high latitude or elevation habitats due to limits of cold tolerance. However, isolated populations at the edge of these species' geographic ranges may face a combination of strong selection and lack of maladaptive gene flow that allows them to adapt to the cold and invade further. Here we show that an isolated population of Gambusia affinis (on Cape Cod, MA, USA), one of the most invasive fish in the world, can survive temperatures lower than any reported tolerances for other populations, with large, long-lived females showing more tolerance than males. Indeed, male acute cold tolerance appears insufficient, suggesting the population may persist through winters mainly via the ability of mated females to delay offspring production until spring. This combination of female cold tolerance and life history may open the door for further expansion of this invasive species into high latitude freshwater habitats. [ABSTRACT FROM AUTHOR]

Top predators can exert strong influences on community structure and function, both via direct, consumptive effects, as well as through non-consumptive, fear-based effects (i.e. predation risk). However, these effects are challenging to quantify, particularly for mobile predators in marine ecosystems. To advance this field of research, here we used baited remote underwater video stations (BRUVs) to assess how the behavior of mobile fish species off Cape Cod, Massachusetts, was affected by exposure to large sharks. We categorized sites into three levels of differential shark predation exposure (white sharks, Carcharodon carcharias) and quantified the relative abundance and arrival times (elapsed time before appearing on screen) for six mobile fish prey groups to the BRUV stations. Increased large shark exposure was associated with a decrease in overall prey abundance, but the overall response was prey group-specific. Foraging of smooth dogfish, a likely important prey item for large sharks in the system, was significantly reduced in areas frequented by white sharks. Specifically, the predicted probabilities of smooth dogfish bait contacts or bite attempts occurring were reduced by factors of 5.7 and 8.4, respectively, in areas of high exposure as compared to low exposure. These modifications were underscored by a decrease in smooth dogfish abundance in areas of high exposure as well. Our results suggest that populations of large, roving sharks may induce food-related costs in prey. We discuss the implications of this work within the context of the control of risk (COR) hypothesis, for the purposes of advancing our understanding of the ecological role and effects of large sharks on coastal marine ecosystems. [ABSTRACT FROM AUTHOR]

Estimates of the types and number of recreational users visiting an estuary are critical data for quantifying the value of recreation and how that value might change with variations in water quality or other management decisions. However, estimates of recreational use are minimal and conventional intercept survey methods are often infeasible for widespread application to estuaries. Therefore, a practical observational sampling approach was developed to quantify the recreational use of an estuary without the use of surveys. Designed to be simple and fast to allow for replication, the methods involved the use of periodic instantaneous car counts multiplied by extrapolation factors derived from all-day counts. This simple sampling approach can be used to estimate visitation to diverse types of access points on an estuary in a single day as well as across multiple days. Evaluation of this method showed that when periodic counts were taken within a preferred time window (from 11 am–4:30 pm), the estimates were within 44% of actual daily visitation. These methods were applied to the Three Bays estuary system on Cape Cod, USA. The estimated combined use across all its public access sites is similar to the use at a mid-sized coastal beach, demonstrating the value of estuarine systems. Further, this study is the first to quantify the variety and magnitude of recreational uses at several different types of access points throughout the estuary using observational methods. This work can be transferred to the many small coastal access points used for recreation across New England and beyond. [ABSTRACT FROM AUTHOR]

Kemp's ridley sea turtles were on the verge of extinction in the 1960s. While these sea turtles have slowly recovered, they are still critically endangered. In the last few years, the number of strandings on the beaches of Cape Cod, Massachusetts has increased by nearly an order of magnitude relative to preceding decades. This study uses a combination of ocean observations and a well-respected ocean model to investigate the causes and transport of cold-stunned sea turtles in Cape Cod Bay. After validating the model using satellite-tracked drifters and local temperature moorings, ocean currents were examined in Cape Cod Bay in an attempt to explain stranding locations as observed by volunteers and, for some years, backtracking was conducted to examine the potential source regions. The general finding of this study is that sub 10.5°C water temperatures in combination with persistently strong wind stress (>0.4 Pa), results in increased strandings along particular sections of the coast and are dependent on the wind direction. However, it is still uncertain where in the water column the majority of cold-stunned turtles reside and, if many of them are on the surface, considerable work will need to be done to incorporate the direct effects of wind and waves on the advective processes. [ABSTRACT FROM AUTHOR]

Transatlantic stock mixing in basking sharks Cetorhinus maximus is supported by low genetic diversity in populations throughout the Atlantic Ocean. However, despite significant focus on the species' movements; >1500 individual sharks marked for recapture and >150 individuals equipped with remote tracking tags, only a single record of transatlantic movment has been previously recorded. Within this context, the seredipitous re‐sighting of a female basking shark fitted with a satellite transmitter at Malin Head, Ireland 993 days later at Cape Cod, USA is noteworthy. [ABSTRACT FROM AUTHOR]

The recently described oak gall wasp Zapatella davisae Buffington & Melika (Hymenoptera: Cynipidae) has caused extensive damage and mortality to black oak trees, Quercus velutina L. (Fagales: Fagaceae), in coastal parts of New England, United States. Like many newly described and/or newly introduced species, it is unclear how long populations of Z. davisae have existed in this region. However, as this species forms galls on the woody-tissue of its host, it may be possible to obtain historical information about changes in its population size by examining the presence of galls in relation to annual growth nodes. Here, we explore the utility of this approach to determine population size changes in Z. davisae densities on Nantucket, Martha's Vineyard, and Cape Cod, Massachusetts, through dissection of black oak branches. In addition, we calculated parasitism rates during the years of study and obtained morphological and molecular identifications for the parasitoids associated with Z. davisae. Our results show significant changes in population sizes, with higher levels of parasitism at sites on Martha's Vineyard and Cape Cod compared to sites on Nantucket. In addition, morphological examinations, in combination with DNA sequencing, identified the associated parasitoids as five species in the genus Sycophila Walker (Hymenoptera: Eurytomidae). We comment that considerable morphological variation within several of these recovered species was observed, present the first record of males for a species from which only females have been described, and suggest that future work is required to clarify the species boundaries for this important parasitoid group. [ABSTRACT FROM AUTHOR]

Colonization of eelgrass (Zostera marina L.) by tunicates can lead to reduced plant growth and survival. Several of the tunicate species that are found on eelgrass in the northwest Atlantic are highly aggressive colonizers, and range expansions are predicted in association with climate-change induced increases in seawater temperature. In 2017, we surveyed tunicates within eelgrass meadows at 33 sites from New Jersey to Newfoundland. Eight tunicate species were identified colonizing eelgrass, of which four were non-native and one was cryptogenic. The most common species (Botrylloides violaceus and Botryllus schlosseri) occurred from New York to Atlantic Canada. Tunicate faunas attached to eelgrass were less diverse north of Cape Cod, Massachusetts. Artificial substrates in the vicinity of the eelgrass meadows generally supported more tunicate species than did the eelgrass, but fewer species co-occurred in northern sites than southern sites. The latitudinal gradient in tunicate diversity corresponded to gradients of summertime sea surface temperature and traditional biogeographical zones in the northwest Atlantic, where Cape Cod represents a transition between cold-water and warm-water invertebrate faunas. Tunicate density in the eelgrass meadows was low, ranging generally from 1-25% cover of eelgrass shoots, suggesting that space availability does not currently limit tunicate colonization of eelgrass. This survey, along with our 2013 survey, provide a baseline for identifying future changes in tunicate distribution and abundance in northwest Atlantic eelgrass meadows. [ABSTRACT FROM AUTHOR]

Water quality criteria are necessary to ensure protection of ecological and human health conditions, but compliance can require complex decisions. We use structured decision making to consider multiple stakeholder objectives in a water quality management process, with a case study in the Three Bays watershed on Cape Cod, Massachusetts. We set a goal to meet or exceed a nitrogen load reduction target for the watershed and four key objectives: minimizing economic costs of implementing management actions, minimizing the complexity of permitting management actions, maximizing stakeholder acceptability of the management actions, and maximizing the provision of ecosystem services (recreational opportunity, erosion and flood control, socio‐cultural amenity). We used multi‐objective optimization and sensitivity analysis to generate many possible solutions that implement different combinations of nitrogen‐removing management actions and reflect tradeoffs between the objectives. Results show technological advances in controlling household nitrogen sources could provide lower cost solutions and positive impacts to ecosystem services. Although this approach is demonstrated with Cape Cod data, the decision‐making process is not specific to any watershed and could be easily applied elsewhere. Research Impact Statement: Structured decision making is a systematic decision‐support process that can be used to help decision makers meet a nitrogen loading mandate in coastal watersheds in the U.S. [ABSTRACT FROM AUTHOR]

Population dynamics of sessile marine invertebrates are potentially affected by variation in abiotic variables among microhabitats. The ribbed mussel (Geukensia demissa), an ecosystem engineer in salt marshes from Cape Cod to northern Florida, inhabits two microhabitats in salt marshes near its northern range limit, Maritime Canada: the exposed seaward edge of the marsh (edge) and the edge of creeks (creek). To determine differences in population dynamics of ribbed mussels between these microhabitats, population, demographic, and abiotic variables were measured at multiple sites over 1 to 2 years. Water flow was higher, temperature less variable, and winter shoreline disturbance less prevalent along creeks than edges. Mussels showed some minor demographic differences between microhabitats: a slightly delayed onset of gametogenesis, and a tendency to lower female reproductive output and more settlers (although overall numbers were low) within creeks. These differences did not translate into consistent differences in population variables across microhabitat types, namely density, size structure, and individual growth of juveniles and adults. Although creeks appear to be more suitable habitat based on abiotic variables measured, mussel population variables may be limited by a combination of temperature and food availability or quality, or some other factor. Overall, population dynamics of ribbed mussels are similar between creek and edge microhabitats in salt marshes in Maritime Canada. This study contributes a first assessment of the dynamics of a potentially key salt marsh species near its northern range limit. [ABSTRACT FROM AUTHOR]

This work introduces the concept of parametric Gaussian processes (PGP), which is built upon the seemingly self-contradictory idea of making Gaussian processes parametric. The resulting framework is capable of encoding massive amount of data into a small number of "hypothetical" data points. Moreover, parametric Gaussian processes are well aware of their imperfections and are capable of properly quantifying the uncertainty in their predictions associated with such limitations. The effectiveness of the proposed approach is demonstrated using three illustrative examples, including one with simulated data, a benchmark with dataset in the airline industry with approximately 6 million records, and spatio-temporal sea surface temperature maps in Massachusetts and Cape Cod Bays and Stellwagen Bank for the year 2015. [ABSTRACT FROM AUTHOR]

Twelve months of measurements collected during the Two-Column Aerosol Project field campaign at Cape Cod, Massachusetts, which started in the summer of 2012, were used to investigate aerosol physical, optical, and chemical properties and their influences on the dependence of cloud development on thermodynamic (i.e., lower tropospheric stability, LTS) conditions. Relationships between aerosol loading and cloud properties under different dominant air-mass conditions and the magnitude of the first indirect effect (FIE), as well as the sensitivity of the FIE to different aerosol compositions, are examined. The seasonal variation in aerosol number concentration (Na) was not consistent with variations in aerosol optical properties (i.e., scattering coefficient, σs , and columnar aerosol optical depth). Organics were found to have a large contribution to small particle sizes. This contribution decreased during the particle growth period. Under low-aerosol-loading conditions, the liquid water path (LWP) and droplet effective radius (DER) significantly increased with increasing LTS, but, under high-aerosol-loading conditions, LWP and DER changed little, indicating that aerosols significantly weakened the dependence of cloud development on LTS. The reduction in LWP and DER from low- to high-aerosol-loading conditions was greater in stable environments, suggesting that clouds under stable conditions are more susceptible to aerosol perturbations than those under more unstable conditions. High aerosol loading weakened the increase in DER as LWP increased and strengthened the increase in cloud optical depth (COD) with increasing LWP, resulting in changes in the interdependence of cloud properties. Under both continental and marine air-mass conditions, high aerosol loading can significantly increase COD and decrease LWP and DER, narrowing their distributions. Magnitudes of the FIE estimated under continental air-mass conditions ranged from 0.07±0.03 to 0.26±0.09 with a mean value of 0.16±0.03 and showed an increasing trend as LWP increased. The calculated FIE values for aerosols with a low fraction of organics are greater than those for aerosols with a high fraction of organics. This implies that clouds over regions dominated by aerosol particles containing mostly inorganics are more susceptible to aerosol perturbations, resulting in larger climate forcing, than clouds over regions dominated by organic aerosol particles. [ABSTRACT FROM AUTHOR]

This study proposes a new mathematical model for describing the drawdown distribution due to a constant rate pumping (CRP) in an unconfined aquifer considering the lagging theory. We introduce two lag times in Darcy's law and in turn in a free surface equation to reflect the effects of the capillary fringe and the capillary suction on the water table motion. The present free surface equation can reduce to those used in previous studies. The Laplace and Weber transform methods are used to derive the semianalytical solution to the model including the effect of wellbore storage. The algorithm of numerical Laplace inversion is applied to obtain the transient solution of the model. We find that the delay index, commonly used in the literature, is equivalent to the lag time associated with the effect of the capillary suction. The sensitivity analysis is performed to assess the drawdown behavior in response to the change in each aquifer parameter. The drawdown distributions predicted by the present solution agree fairly well to the field data taken from CRP tests at Cape Cod, Massachusetts; the Canadian Forces Base Borden, Ontario; and Saint Pardon de Conques, Gironde (France). The lag times determined by both CRP tests seem to decrease linearly with increasing distance on the logarithmic scale from the pumping well. The consideration of two lag times considerably improves the accuracy in estimated specific yields. Key Points: This study develops a new model for describing unconfined flow due to pumping by introducing two lag time parameters in Darcy's lawThe parameters in a linearized free surface equation are considered to reflect the effects of capillary fringe and force on drawdownField data are analyzed based on the solution of the model and least squares approach to determine aquifer parameters [ABSTRACT FROM AUTHOR]

The role of planning support systems has become closely aligned with the dominant theoretical paradigms - primarily collaborative planning and communicative rationality - within the field of urban planning. However, scholars from Human-Computer Interaction have built a theoretical tradition drawing on Activity Theory, among others, to describe computer supported collaborative learning. Collaboration, from this perspective, represents a form of distributed learning situated within a social interaction. Individuals work with each other and technology to converge on shared conceptual understandings of the problem space and to develop a shared praxis for collaboratively addressing those problems. Instead of the tools talking, technology plays a critical role in helping stakeholders develop a common ground for planning and supporting an activity-aware praxis. I use empirical examples from a planning process on Cape Cod, Massachusetts to illustrate these features of Computer Supported Collaborative Learning (CSCL) for a planning audience. I focus, in particular, on how planning support systems mediate group judgments about space and scale to account for spatial scale mismatches between the Cape's watersheds and towns. [ABSTRACT FROM AUTHOR]

Dichlorodiphenyltrichloroethane was used on Cape Cod, Massachusetts (USA), for mosquito and gypsy moth mitigation, from 1948 until the insecticide was banned in the 1970s. There are historical accounts of major spray events, and DDT was expected to have remained immobile in the organic-rich sediments of local ponds. We investigated the potential for sediment cores from lakes on Cape Cod to reveal the depositional history of DDT. This compound and its metabolites dichlorodiphenyldichloroethane and dichlorodiphenyldichloroethylene (ΣDDT) were examined in sediment cores from four kettle lakes on Cape Cod that lie between the towns of Brewster and Harwich, where there is a detailed history of aerial spraying. Sediment cores were dated via 210Pb and analyzed for water content, total carbon, total organic carbon, and organochlorine pesticide concentrations. Use of fallout 137Cs to confirm 210Pb dates was unsuccessful, probably because of post-depositional migration of 137Cs. ΣDDT inventories in each lake were determined to be ~ 10 ng cm−2, which represents about 0.1% on an aerial basis of the quantity known to have been sprayed. Compared to the recorded spraying history, the concentration-depth maxima appear decades later than expected. The overall low quantity and unexpected temporal distribution of pesticide residues are probably explained by natural degradation of DDT in the sediment. A novel mathematical correction to DDT concentrations was applied and yielded adjusted inventories close to expected values, and moved the pesticide concentration maxima to the 1950s and 1960s, when they were expected to have occurred. [ABSTRACT FROM AUTHOR]

A recent fatality from a white shark bite in Massachusetts, U.S.A. has led local officials and members of the public to consider culling the population of gray seals in local waters. The seal population, which has been visibly increasing coincident with implementation of the Marine Mammal Protection Act, is thought to have attracted the white shark predators to the area. Were stakeholders to seek scientific evidence to inform a decision to cull, they would find little guidance. This study examines the scientific literature on culling and its impacts both on the species of concern and their ecosystems. Possible culling impacts are considered in the context of the biology and ecology of the Cape gray seal and white shark populations. Results are presented to inform decisionmakers about the feasibility, likely outcome and potential complications of a gray seal cull. The conclusion reached is that culling the Cape Cod gray seals is unlikely to abate the risk of human-white shark encounters on the Cape Cod beaches and could possibly have unforeseen consequences both for the local ecosystem and human activity. [ABSTRACT FROM AUTHOR]

Smith, S.M.; Tyrrell, M.; Medeiros, K.; Bayley, H.; Fox, S.; Adams, M.; Mejia, C.; Dijkstra, A.; Janson, S., and Tanis, M., 2017. Hypsometry of Cape Cod salt marshes (Massachusetts, U.S.A.) and predictions of marsh vegetation responses to sea-level rise. The structure and functioning of salt marsh ecosystems are being impacted by sea-level rise, and a major determinant of their vulnerability to this aspect of climate change is their ground surface elevation relative to tide heights (hypsometry). In this study, a comprehensive real-time kinematic (RTK) global positioning system (GPS) survey was conducted within four salt marshes at Cape Cod National Seashore (CCNS) to create digital elevation models, and in situ water-level loggers were used to collect tidal data within each system. From these data, marsh surface elevations were calculated relative to mean high tide elevations for 2013 and projected elevation change rates with 50 cm and 100 cm of sea-level rise. Vegetation responses to these scenarios were then modeled based on the relationship of high and low marsh zones to relative elevation. The results suggest that (1) CCNS marshes sit low within their tidal frames, unlike the majority of salt marshes in New England, (2) high marsh areas will be most affected with sea-level rise, with 90-100% losses under both 50 cm and 100 cm sea-level rise scenarios, and (3) total marsh losses of up to 30% could ensue with 100 cm of sea-level rise. Such changes, should they occur, would substantially impact the coastal environment on Cape Cod and profoundly impact the ecosystem services provided by these systems. [ABSTRACT FROM AUTHOR]

Hesp, Patrick A.; Smyth, Thomas A.G.; Walker, Ian J.; Gares, Paul A., and Wasklewisz, Thad, 2016. Flow within a trough blowout at Cape Cod. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 288-292. Coconut Creek (Florida), ISSN 0749-0208. The Province Lands dunefield at Cape Cod is characterised by large parabolic dunes on which have developed very significant numbers of active saucer and bowl blowouts. Blowouts occur across the entire dune landscape but many are initiated on the high lee margins of large erosional ridges and bowl blowouts within the larger parabolic dune landscape. Evolution of these blowouts is characterised by multiple stages. The first few evolutionary stages are described. In addition, the aerodynamics and flow structure within a trough blowout and former saucer blowout developed within a high ridge crest is elucidated from 2D sonic anemometer data, smoke bombs and videography. The flow is characterised by decreasing then increasing flow up the blowout centreline, and marked, highly turbulent opposed flow separation immediately inside and around the marginal entrance walls of the blowout. [ABSTRACT FROM AUTHOR]

Distribution shifts poleward are a widespread response to climate change and can result in altered community composition and interactions among species that previously were geographically isolated. The novel communities and species interactions that may arise during range shifts provide an opportunity to study fundamental ecological processes, while also addressing potential conservation issues. Black sea bass (Centropristis striata) historically ranged from the Gulf of Mexico to Cape Cod, but recently have expanded north into the Gulf of Maine. Very little is known about the impact of this range expansion on benthic community structure throughout the coastal waters of the Gulf of Maine. To investigate the effects of sea bass on the behavior of juvenile American lobsters (Homarus americanus), we manipulated the presence of sea bass olfactory cues and quantified shelter use and foraging behavior of lobsters from three regions in the Gulf of Maine with different potential contact histories with sea bass. Sea bass presence increased shelter usage and reduced foraging in lobsters, but contact history influenced the strength of these behavioral responses. Lobsters with no previous contact with sea bass did not significantly increase shelter usage or decrease movement in their presence but did reduce their foraging rate on mussels. This observed reduction in consumption indicates that naïve lobsters recognize novel predators, but the ineffective anti‐predator responses exhibited support the naive prey hypothesis. Meanwhile, lobsters with the longest potential contact history with sea bass significantly increased shelter usage when sea bass were present; however, they exhibited limited movement and foraging behavior in both the absence and presence of sea bass. Finally, lobsters with a short potential contact history with sea bass exhibited increased shelter usage, reduced movement, and reduced mussel consumption in the presence of sea bass, revealing that juvenile lobsters quickly adapt anti‐predator defenses to avoid this novel threat. Overall, these results suggest that prey contact history with novel predators mediates the strength of their nonconsumptive effects, and consequently can influence geographic patterns in predator–prey dynamics. [ABSTRACT FROM AUTHOR]

The great shearwater (Ardenna gravis) is a common pelagic bird with a distribution that spans almost the entire Atlantic basin, which in conjunction with its relatively high abundance, makes great shearwaters an effective bio indicator. We compared δ13C and δ15N values from the feathers, red blood cells (RBCs), and plasma of great shearwaters collected in 2014 and 2015 from the waters off Massachusetts and Cape Cod. The δ13C and δ15N values of RBCs were quite constant between sampling periods and years, suggesting a generally stable food web over that time period. However, the δ13C of plasma indicates a small seasonal change in diet between July and September for both years, with plasma δ15N values suggesting a slight increase in trophic level late in summer. Comparison of the δ15N of RBCs and plasma indicates that great shearwaters experienced a diet shift during the first few weeks of summer 2014, but not in 2015. Comparisons with other studies suggest that these shearwaters feed at a lower trophic level than great shearwaters sampled in the Bay of Fundy and that there is a decrease in δ13C with increasing latitude, which could indicate a more pelagic diet in northern waters. Stable isotope analysis of the sixth primary feathers provided evidence that these feathers are molted in the Northern Hemisphere and that the diet of great shearwaters shortly after arrival was different in 2014 and 2015. This study demonstrates that within species comparisons of tissue isotopic signatures over time and comparisons of isotopic signatures of tissues with different turnover rates, can detect changes in diet and be used as a tool to monitor for changes in marine food webs over time and space. The relevant signals remain informative even in the absence of species-specific data on tissue-diet discrimination factors, tissue turnover rates, or knowledge of dietary components and their stable isotopic signatures, suggesting dietary changes indicative of a corresponding change in the food web. [ABSTRACT FROM AUTHOR]