Eastern Maine Research Articles

Geochronology, geochemistry, and tectonic setting of Ordovician metavolcanic rocks in the Liberty–Orrington belt, Maine: implications for the evolution of peri-Gondwanan arcs in the northern Appalachians

The Yarmouth Island Formation of the East Harpswell Group (EHG) is an assemblage of metamorphosed volcanic and sedimentary rocks exposed in Casco Bay, Maine. Although previously interpreted to have been deposited ca. 445 Ma, two new U–Pb zircon ages from metavolcanic rocks in the unit indicate prolonged magmatism between ca. 469–474 Ma and correlation with adjacent rocks of the more regionally extensive Casco Bay Group (CBG) in the Liberty–Orrington belt. New detrital zircon results from metasedimentary rocks in the EHG support this correlation; the age spectra indicate a peri-Gondwanan sedimentary source, consistent with earlier published results from the CBG. Detailed geochemical studies of the metavolcanic rocks in the Yarmouth Island Formation indicate a wide range of sub-alkaline compositions (SiO2 = 47.9–77.5 wt.%), flat chondrite-normalized rare earth element distributions, and a prominent negative Nb anomaly in normalized spider plots. Tectonic discrimination plots suggest eruption in a volcanic arc setting with continental crustal influence. This tectonic setting, when combined with the co-existence of marine sedimentary rocks, suggests a transitional setting between that of subduction and subsidence in a marine setting, perhaps due to the onset of back-arc rifting. Similarities in age, lithologic character, sediment provenance, and volcanic rock geochemistry indicate a strong correlation between these rocks in the Liberty–Orrington belt and those along strike in the southern portion of the Miramichi belt of eastern Maine and southern New Brunswick. These findings confirm the preservation of >500 km long, ca. 470 Ma, arc/back-arc terrane within the Ganderia superterrane in the northern Appalachians.

An overview of Early Paleozoic arc systems in New Brunswick, Canada, and eastern Maine, USA

A plate tectonic model involving northwesterly retreat of an Iapetan subducting slab has been developed over the last three decades to explain the time span of volcanism recorded within the development of Early Paleozoic arc systems preserved in New Brunswick. These arc systems are referred as the Penobscot arc-backarc (514–482 Ma), and Popelogan–Meductic arc (478–460 Ma). Opening of the Tetagouche backarc basin associated with the Popelogan–Meductic arc was diachronous and heterogeneous and involved volcanism associated mainly with the crustal extension and rifting between 472–455 Ma. The complex evolution of the Tetagouche backarc basin is examined in respect to six sub-basins, containing relatively well documented stratigraphic sections in New Brunswick: namely from northeast to southwest the Fournier, California Lake, Bathurst, Sheephouse Brook, Napadogan, and Becaguimec sub-basins. Recently, alternate plate tectonic models have been proposed for the northern Appalachians based on newly acquired geochronological data from northern Maine. We integrate these new data with existing stratigraphic, structural, paleontological, and geochemical evidence to support and refine the previously proposed migrating-arc model for New Brunswick and Maine.

Increasing simulation to improve confidence during medication administration in associate degree nursing students

At Eastern Maine Community College (EMCC) students are taught the skills needed for medication administration (MA) in the first semester of their nursing education career. Following the successful completion of their MA evaluation, students are allowed to pass medications with their instructor during clinical rotations. Nursing students work to acquire and refine the practical experience and critical thinking necessary to safely administer medications. Students remark that they lack confidence when administering medications due to minimal opportunities to perform the actual skill during clinical experiences (Schneidereith, 2021). MA errors still occur at alarming rates within health systems across the world, and the significance of medication safety is of paramount importance in terms of nursing education (Jones et al., 2022). Although a lack of MA experiences may occur for many reasons, faculty need to be mindful of the student experience and find adjunctive ways to provide MA opportunities. In fostering this crucial skill, the proposition of increasing the number of MA simulations offered could close the gap in student confidence in this skill.

Regional impact of large-scale climate oscillations on ice out variability in New Brunswick and Maine.

The available ice out (the date of disappearance of ice from a water body) records were analyzed from four relatively closely spaced lakes in southwestern New Brunswick (Harvey, Oromocto, Skiff) and eastern Maine (West Grand Lake), with the longest set of available observations being for Oromocto Lake starting in 1876. Results of a coherence analysis carried out on the ice out data from the four lakes indicates that there is regional coherence and correspondingly, that regional drivers influence ice out. These results also indicate that ice out dates for lakes from the region where records have not been kept can also be interpolated from these results. As the ice out record was coherent, further analysis was done for only Oromocto Lake on the basis of it having the longest ice out record. Cross-wavelet analysis was carried out between the ice out record and a variety of cyclic climate teleconnections and the sunspot record to identify which phenomena best explain the observed ice out trends. The most important observed contributors to ice out were the North Atlantic Oscillation (NAO) and the El Niño Southern Oscillation (ENSO), with observed periodicities at the interannual scale. At the decadal scale the Pacific Decadal Oscillation (PDO) and the 11-year solar cycle were the only patterns observed to significantly contribute to ice out.

Projected effects of climate change on Pseudo-nitzschia bloom dynamics in the Gulf of Maine.

Worldwide, warming ocean temperatures have contributed to extreme harmful algal bloom events and shifts in phytoplankton species composition. In 2016 in the Gulf of Maine (GOM), an unprecedented Pseudo-nitzschia bloom led to the first domoic-acid induced shellfishery closures in the region. Potential links between climate change, warming temperatures, and the GOM Pseudo-nitzschia assemblage, however, remain unexplored. In this study, a global climate change projection previously downscaled to 7-km resolution for the Northwest Atlantic was further refined with a 1-3-km resolution simulation of the GOM to investigate the effects of climate change on HAB dynamics. A 25-year time slice of projected conditions at the end of the 21st century (2073-2097) was compared to a 25-year hindcast of contemporary ocean conditions (1994-2018) and analyzed for changes to GOM inflows, transport, and Pseudo-nitzschia australis growth potential. On average, climate change is predicted to lead to increased temperatures, decreased salinity, and increased stratification in the GOM, with the largest changes occurring in the late summer. Inflows from the Scotian Shelf are projected to increase, and alongshore transport in the Eastern Maine Coastal Current is projected to intensify. Increasing ocean temperatures will likely make P. australis growth conditions less favorable in the southern and western GOM but improve P. australis growth conditions in the eastern GOM, including a later growing season in the fall, and a longer growing season in the spring. Combined, these changes suggest that P. australis blooms in the eastern GOM could intensify in the 21st century, and that the overall Pseudo-nitzschia species assemblage might shift to warmer-adapted species such as P. plurisecta or other Pseudo-nitzschia species that may be introduced.

Wind‐Modulated Western Maine Coastal Current and Its Connectivity With the Eastern Maine Coastal Current

AbstractUsing a high‐resolution circulation model and an offline particle tracking model, we investigated variations of the Western Maine Coastal Current (WMCC) and its connectivity with the Eastern Maine Coastal Current (EMCC). The models showed that the weak, broad, and sinuous WMCC is generally southwestward with an offshore and a nearshore core, fed by the extension of the EMCC and runoff from the Penobscot and Kennebec–Androscoggin Rivers, respectively. A sea‐level dome can form offshore of Casco Bay in late fall and early winter as the northeastward alongshore wind sets up a seaward sea‐level gradient from the coast to meet the shoreward sea‐level gradient from Wilkinson Basin. Consequently, northeastward flows (i.e., the counter‐WMCC) emerge on the inshore side of the dome. Both the circulation and particle tracking models suggested that the connectivity generally peaks twice annually, highest in winter and then secondarily in late spring or early summer. The former is concurrent with the most southwest offshore veering of the EMCC, while the latter is concurrent with the strongest EMCC. Moreover, the counter‐WMCC can reduce the connectivity and result in year‐to‐year variations.

Stable isotopes reveal minimal spatial and temporal variation in diet of the wrymouth (Cryptacanthodes maculatus)

AbstractPredation by infaunal and epibenthic predators is often an important determinant of marine soft‐bottom community structure. The role of the predatory, benthic‐dwelling fish, the wrymouth (Cryptacanthodes maculatus), in the soft‐bottom food web has received little attention. The purpose of our study was to examine spatial and temporal variability in diet and trophic position of wrymouth at two lower intertidal sites in eastern Maine, USA. Wrymouth, their potential prey, and primary producers were collected in the spring and summer of 2013 in Machiasport and Beals, Maine. Stable isotope analysis was used to determine trophic position of the fish and its potential diet. Wrymouth δ13C signatures were influenced by location and ranged from −12.6‰ to −11.5‰, whereas δ15N signatures varied little (12.3‰–12.7‰) between locations or seasons. Wrymouth trophic position ranged from 3.02 to 3.48, indicating that they are tertiary consumers. The intertidal zone consisted of two distinct clusters of taxa, characterized by the presence of either macroalgae (mostly fucoids) or eelgrass (Zostera marina). Wrymouth diet consisted primarily of predatory polychaetes. Stable carbon and nitrogen isotope signatures varied across seasons and locations for multiple species, including our base species, Mya arenaria. Results suggest wrymouth are generalist feeders with limited seasonal and spatial variation in diet. Bottom‐up processes, however, are fundamentally different between the two study sites and influence their trophic structure. This result highlights the importance of collecting baseline data and evaluating trophic interactions at multiple spatial scales within small regional areas in coastal systems.

Seasonal Variations and Driving Factors of the Eastern Maine Coastal Current

AbstractTo investigate the coastal current in the Gulf of Maine (GoME) and its relation to forcing from outside of the gulf, a high‐resolution circulation model was developed and validated. Our model shows that the Eastern Maine Coastal Current (EMCC) possesses two cores, an offshore and a nearshore core that peak in summer and spring, respectively. The two cores can be traced back to outflows from the Bay of Fundy from opposite sides of Grand Manan Island, and both cores are deeper and slightly more onshore in summer and fall in response to tidal mixing, surface thermal stratification and wind. The two cores merge south of Pleasant Bay, then split into two branches again east of Mount Desert Rock, where the nearshore branch flows along the coast, while the offshore branch turns southward to recirculate in the eastern GoME. Subject to variations of Scotian Shelf Water and Slope Water (SW) inflows, the offshore veering occurs further upstream (northeastward) in late winter and summer, but gradually shifts downstream (southwestward) from summer to winter. Diagnosis of momentum balance demonstrates that the EMCC is primarily driven by the pressure gradient force (PG), of which the barotropic PG is dominant and offshore, while the baroclinic PG is onshore and increases with depth. The large baroclinic PG at depths, modulated by SW, that is, blended by tidal mixing, offsets the barotropic PG. Near the surface, the barotropic PG is nearly balanced by the Coriolis force, forming the geostrophic EMCC.

Comparing the Efficacy of a Nurse-Driven and a Physician-Driven Diabetic Ketoacidosis (DKA) Treatment Protocol.

BackgroundStandardized DKA treatment could result in better overall safety and efficacy outcomes. The primary objective of this study is to validate the efficacy of an adapted nurse-driven DKA protocol compared to a physician-driven DKA protocol across the continuum of three hospital settings: the University of Colorado upon which the physician-driven protocol is based, Northern Light Eastern Maine Medical Center (NLEMMC), and Northern Light Sebasticook Valley Hospital (NLSVH). The secondary objective is to assess the safety of the adapted nurse-driven DKA protocol adapted at NLEMMC and NLSVH through determining the incidence of hypoglycemia and anion gap reopening.Patients and MethodsThis was a retrospective, IRB-approved, multi-center study that included: patients 18 years or older who were treated with the DKA protocol at NLEMMC or NLSVH, and admitted to the emergency department between July 2015 and October 2020 with a primary diagnosis of DKA and an elevated anion gap greater than or equal to 13 mEq/L.ResultsA total of 90 patients from NLEMMC and 64 patients from NLSVH were included and compared to 111 patients from the University of Colorado who were included in the post protocol implementation group. There was no statistically significant difference in the primary outcome, time to anion gap closure, between the original University of Colorado study (10.3 hours) and the NLEMMC (10.9 hours, p = 0.420) and NLSVH (8.8 hours, p = 0.115) results presented in this study.ConclusionThe standardized nurse-driven DKA treatment protocol at NLEMMC and NLSVH showed no statistical difference in time to anion gap closure compared to the University of Colorado study upon which it was based. This finding is particularly relevant to hospitals such as NLEMMC and NLSVH that lack provider resources and teams of endocrinologists required for the physician-driven DKA protocol.

Utilization of palliative care services in patients who died from stage IV non-small cell lung cancer (NSCLC): A retrospective study from a tertiary care center in rural Maine.

95 Background: It is known that palliative care involvement in metastatic NSCLC cancer patients has been shown to improve quality of life in previous studies. The aim of our study was to analyze the utilization of palliative care services among patients who died from NSCLC and the setting in which these patients first received palliative care. Methods: This is a retrospective chart review analysis of patients with stage IV NSCLC who were diagnosed at Eastern Maine Medical center and the affiliated cancer center who died between January 2016 and December 2018. We collected demographic data, date and stage of diagnosis, location of palliative referral, location of first palliative care contact with the patient, time between diagnosis and death, utilization of hospice services and time between the initial palliative care consult and death. Results: 255 patients with stage IV NSCLC died between 2016 and 2018. Mean age was 65.5 years. Women were 49% and men were 51%. Majority (60%) of patients had good performance status with ECOG score between 0-1 at presentation. All 255 patients were referred to palliative care. The location of initial palliative care referral following diagnosis was 40% from the hospital, 32% from the oncology clinic and 28% from the outpatient specialist or PCP office. Overall, 174 patients (68%) were seen by palliative care and 81 (32%) were not seen. Of the patients seen 119 (68%) had their initial palliative evaluation in the hospital, and 55 (32%) in the clinic. Majority (55%) had more than one follow-up visit. Consults initiated in the inpatient setting were more likely to be seen by palliative care than in the outpatient setting (p 0.0009). Time between diagnosis to palliative care consult was less than one month in 39%, 1-2 months in 25%, 2-6 months in 21%, and more than 6 months in 14% patients. Patients seen by palliative care had a more likelihood to end up on hospice (p 0.09). The majority of patients seen by palliative care (53%) died within a month of initial consultation. Conclusions: All patients in our study population were referred to palliative care with 100% provider compliance. Among these, 68% were seen by palliative care. Interestingly, inpatient referrals were more likely to be seen by palliative care than the outpatient referrals. We think this is likely related to ease of access to palliative care team in the hospital as well as some of the patients being at terminal stages of their disease. About 33% of patients died within a month of their initial diagnosis, likely giving palliative care team a shorter window of opportunity to be seen in the outpatient setting. Prioritizing referrals of stage IV NSCLC patients might decrease the wait time after initial referral and increase the availability of palliative care services to these patients.

Maine’s Mode of Privateering: A Tale of Fraud and Collusion in the Northeast Borderlands, 1812–1815

The American declaration of war passed by Congress in June 1812 was followed by a prize act which authorised the issuing of Letters of marque. These commissions or licenses allowed American citizens to fit out privately armed vessels to seize British ships. Although most privateers complied with Congress’s instructions, their counterparts operating along the Maine coast used their commissions to further own economic self-interest by orchestrating pre-arranged captures with British merchants in Nova Scotia and New Brunswick. Since the British government encouraged its subjects to trade with the enemy to undermine the American war effort, American privateers assumed most of the risks. Merchants and mariners from as far away as New York and Connecticut traveled to Maine to trade with the British despite the hazards of detection. As these privateers engaged in fraud, other Americans turned to vigilante violence to uncover and foil these schemes. After the British occupied Eastern Maine in the summer of 1814 trading with the enemy became illegal on the British side of the border. Despite the risks, British merchants continued to engage in trade with the enemy. Ultimately, persistence of conflict and accommodation in the Northeastern Borderlands, the area comprising Maine, Nova Scotia and New Brunswick, helped undermined Eastern Maine’s allegiance to the United States.

Hocus pocus or POCUS: Ultrasound for diagnosing pneumonia in children

Northern Light Eastern Maine Medical Center, Family Medicine Center and Residency Program, Bangor, ME The author declares no conflicts of interest.

Identifying Gaps in Knowledge and Barriers to Utilization of Hospice and End-of-Life Care Services

Hospice and end-of-life (HEOL) services have traditionally been underutilized, especially in rural areas. A community assessment, performed in eastern Maine, sheds light on the extent to which public and health care professional attitudes and knowledge explain HEOL service access and utilization levels. Structured surveys were distributed in the fall of 2019 targeting community residents (18 years and older) and hospice/health care professionals. Residents (n=213) displayed significant levels of ignorance concerning the purpose and availability of HEOL services. Although a range of HEOL services were rated as highly important, residents were unable to confirm their actual availability. Overall, one in every two residents did not know if particular HEOL services existed locally (ranging from a low of 27% that were unsure whether grief support services were available to 67% unaware of the presence of a community hospice house). Hospice/health professionals (n=22) were aligned in their belief that the public did not have a clear understanding of the intent of HEOL services. Interestingly, community residents lacked equivalent measures of confidence in the HEOL knowledge levels of health care professionals. Significant barriers to the timely utilization of HEOL services included: stigma/fear, lack of education as to the purpose of these services, financial barriers to access, and scarcity of selected HEOL services. For both respondent groups, the top ranking suggestions for increasing HEOL services utilization were earlier discussions between providers and patients concerning the need for such services and increased public and professional education around death and dying.

Reversal of Forest Soil Acidification in the Northeastern United States and Eastern Canada: Site and Soil Factors Contributing to Recovery

As acidic deposition has decreased across Eastern North America, forest soils at some sites are beginning to show reversal of soil acidification. However, the degree of recovery appears to vary and is not fully explained by deposition declines alone. To assess if other site and soil factors can help to explain degree of recovery from acid deposition, soil resampling chemistry data (8- to 24-year time interval) from 23 sites in the United States and Canada, located across 25° longitude from Eastern Maine to Western Ontario, were explored. Site and soil factors included recovery years, sulfate (SO42−) deposition history, SO42− reduction rate, C horizon pH and exchangeable calcium (Ca), O and B horizon pH, base saturation, and exchangeable Ca and aluminum (Al) at the time of the initial sampling. We found that O and B horizons that were initially acidified to a greater degree showed greater recovery and B horizon recovery was further associated with an increase in recovery years and lower initial SO42− deposition. Forest soils that seemingly have low buffering capacity and a reduced potential for recovery have the resilience to recover from the effects of previous high levels of acidic deposition. This suggests, that predictions of where forest soils acidification reversal will occur across the landscape should be refined to acknowledge the importance of upper soil profile horizon chemistry rather than the more traditional approach using only parent material characteristics.

Finfish Diversity and Distribution in a Boreal, Macrotidal Bay

Cobscook Bay is an 11- km2 geographically complex, boreal, and macrotidal bay in eastern Maine. The physical environment, primary producers, and invertebrate assemblage of the bay are well-characterized, but no contemporary data exist on its finfish assemblage. We sampled the finfish assemblage of Cobscook Bay from 2011 to 2013 in May, June, August, and September to create a baseline dataset suitable for future comparisons. We also examined the composition, diversity, and annual changes in the assemblage. We sampled in the subtidal and intertidal zones using seines (n = 390), fyke nets (n = 72), and benthic (n = 112) and pelagic (n = 111) trawls; sampling was divided among the bay's 3 different sub-bays. We collected more than 60,000 individuals from 46 species. We employed species richness, Simpson's index of diversity, and non-metric multidimensional scaling (with the Bray—Curtis and Horn—Morisita indices) to examine spatial and temporal variation of finfish assemblages throughout the bay. Our analysis suggested that data collected in the subtidal pelagic were not a representative sample of that assemblage. Therefore, we considered 2 assemblages: the intertidal and subtidal benthic. Assemblage composition and species' relative abundances were different at diel, monthly, and annual timescales and were associated with changes in the catch rate of ubiquitous species. In the intertidal, these species included Gasterosteus aculeatus (Threespine Stickleback), Clupea harengus (Atlantic Herring), Alosa pseudoharengus (Alewife), and Menidia menidia (Atlantic Silverside). In the subtidal, the common species were Atlantic Herring and Pseudopleuronectes americanus (Winter Flounder). Statistical analyses indicated that both spatial and temporal factors were significant predictors of assemblage evenness. The sampling design, albeit complex, was sufficient to capture these differences and characterize these assemblages. Implications for future studies are that the study design must be sufficiently complex to capture the anticipated spatial and temporal variability inherent in such dynamic environments. Furthermore, given recent warming trends in the Gulf of Maine, this study's results suggest the importance of thoroughly understanding local temporal and ecosystem variability.

SHRIMP U–Pb zircon evidence for age, provenance, and tectonic history of early Paleozoic Ganderian rocks, east-central Maine, USA

SHRIMP U–Pb zircon ages from Ganderia in eastern Maine clarify the ages and provenance of basement units in the Miramichi and St. Croix terranes and of cover rocks in the Fredericton trough and Central Maine/Aroostook-Matapedia basin (CMAM). These new data constrain timing of orogenic events and help understand the origin of the cover rock depocenters.Detrital zircon data generally confirm suggested ages of the formations sampled. Zircon grains with ages of ca. 430 Ma in both depocenters, only slightly older than their host rocks, were probably derived from the earliest volcanic eruptions in the Eastport-Mascarene belt. Their presence indicates that unnamed CMAM sandstone units may be as young as Pridoli and their absence from the Appleton Ridge and Digdeguash formations suggests that these formations are older than initial Eastport-Mascarene volcanism. Detrital and volcanic zircon ages confirm a Late Cambrian to Middle Ordovician age for the Miramichi succession and date Miramichi volcanism at 469.3 ± 4.6 Ma. In the St. Croix terrane, zircon grain with an age of 477.4 ± 3.7 Ma from an ashfall at the base of the Kendall Mountain Formation and age spectra and fossils from overlying quartz arenite suggest that the formation may span Floian to Sandbian time. The main source of CMAM and Fredericton sediment was recycled Ganderian basement from terranes emergent after Late Ordovician orogenesis, supplemented by Silurian tephra. Zircon barcodes and lithofacies and tectonic models suggest little, if any, input from Laurentia or Avalonia.Zircon- and fossil-based ages indicate coeval Upper Ordovician deformation in the St. Croix (ca. 453 to 442 Ma) and Miramichi (ca. 453 to 446 Ma) terranes. Salinic folding in the southeastern Fredericton trough is bracketed between the 421.9 ± 2.4 Ma age of the Pocomoonshine gabbro-diorite and 430 Ma detrital zircons in the Flume Ridge Formation. Zircon ages, lithofacies analysis, and paleontological evidence support the origin of the Fredericton trough as a Salinic foredeep. The CMAM basin cannot have been an Acadian foreland basin, as sedimentation began millions of years before Acadian subduction.

Methane and carbon dioxide dynamics within four vernal pools in Maine, USA

Vernal pools are small, seasonal wetlands that are a common landscape feature contributing to biodiversity in northeastern North American forests. Basic information about their biogeochemical functions, such as carbon cycling, is limited. Concentrations of dissolved methane (CH4) and carbon dioxide (CO2) and other water chemistry parameters were monitored weekly at the bottom and surface of four vernal pools in central and eastern Maine, USA, from April to August 2016. The vernal pools were supersaturated with respect to CH4 and CO2 at all sampling dates and locations. Concentrations of dissolved CH4 and CO2 ranged from 0.4 to 210 μmol L−1 and 72–2300 μmol L−1, respectively. Diffusive fluxes of CH4 and CO2 into the atmosphere ranged from 0.2 to 73 mmol m−2 d−1, and 30–590 mmol m−2 d−1, respectively. During the study period, the four vernal pools emitted 0.1–5.8 kg C m−2 and 9.6–120 kg C m−2 as CH4 and CO2, respectively. The production fluxes (production rates normalized to surface area) of CH4 and CO2 ranged from − 0.02 to 0.66 and 0.40–4.6 g C m−2 d−1, respectively, and increased significantly over the season. Methane concentrations were best predicted by alkalinity, ortho-phosphate and depth, while CO2 concentrations were best predicted with only alkalinity. Alkalinity as a predictor variable highlights the importance of anaerobic respiration in production of both gases. Our study pools had large concentrations and effluxes of CH4 and CO2 compared to permanently inundated wetlands, indicating vernal pools are metabolically active sites and may be important contributors to the global carbon budget.

Biology of four sympatric sticklebacks in Cobscook Bay, Maine, a boreal, macrotidal bay

Four species of sticklebacks were collected during May, June, August, and September 2011–2013 in a survey of fishes of Cobscook Bay, a macrotidal bay in eastern Maine, U.S.A. Threespine (Gasterosteus aculeatus) and ninespine (Pungitius pungitius) sticklebacks have circumpolar distributions; blackspotted (Gasterosteus wheatlandi) and fourspine (Apeltes quadracus) sticklebacks are limited to northeastern North America. Sticklebacks were collected in the intertidal zone with beach seines and in the pelagic zone with trawls. Up to 30 individuals of each species from each sample were measured and weighed. Individuals were identified as gravid or not in 2012 and 2013. Catch-per-unit-efforts of the most abundant threespine (18,878 individuals) and second most abundant blackspotted sticklebacks (2433) were greatest in the innermost part of the bay, on mudflats, in 2012, and in August. Fewer than 100 fourspine and fewer than 50 ninespine sticklebacks were caught over the three years, mostly in the inner bay. Length-frequency distributions suggested age classes of 0+, 1+, 2+ and a few 3+ for threespine sticklebacks and 0+ and 1+ for blackspotted sticklebacks. Most gravid individuals of those two species were present in May and June. Spawning occurred earlier in 2012, an unusually warm year, than in 2013. Changes in presence, timing, and abundance of other species in the fish survey corroborated the influence of the record warm conditions in 2012 in the Gulf of Maine on the fish community of Cobscook Bay. Blackspotted and ninespine sticklebacks are vulnerable to population decline from warming in the Gulf of Maine because they are near the southern limits of distribution.

Increasing prevalence of epizootic shell disease in American lobster from the nearshore Gulf of Maine

Epizootic shell disease (ESD) is a significant concern to the southern New England lobster fishery. Although ESD has been reported in the southern Gulf of Maine off Massachusetts, there are few reports from Maine waters. We report on the occurrence and distribution of ESD in American lobsters from nearshore Gulf of Maine from the Maine Commercial Lobster Sea Sampling Program. Overall, average prevalence levels of ESD by trip were very low ( 127 mm CL) lobsters, regardless of sex and reproductive state, with much higher prevalence levels (up to 22%). Spatially, prevalence levels of ESD were significantly higher in western regions of the Gulf of Maine than off eastern Maine. Using histology and microbiome analyses, the etiology of the disease was investigated and common signs of lobsters with ESD were described. Aquimarina homari, a bacterium associated with ESD, was significantly more prevalent on lobsters with lesions and abundance was correlated with severity of ESD. Our report indicates that ESD is present on lobsters throughout the nearshore waters of the Gulf of Maine. Given the effect of the disease on lobsters from southern New England and its increasing prevalence over time, further monitoring of ESD in the Gulf of Maine is warranted.

Nearshore Flow Patterns in a Complex, Tidally Driven System in Summer: Part I. Model Validation and Circulation

AbstractCirculation models are often validated with respect to temporal rather than spatial variability, yet spatial variability is often very important for many questions subsequently addressed with the models. We validated a high‐resolution nearshore circulation model using both temporal and spatial data sets and used the model to investigate small‐scale nearshore flow patterns along the complex eastern Maine coast. The Finite Volume Coastal Ocean Model (FVCOM) was run from April to September 2014. In the temporal comparison, the model captured variation in sea level (model skill of 0.98) and the seasonal warming trend (model skill of 0.94). Temperature fluctuations were largely due to horizontal temperature divergence, implying the sensitivity to the forcing at the open boundary. To evaluate spatial variation in performance, we calculated model skill for current profile transects, which ranged from 0.99 to 0.60 in the east/west direction and 0.99 to 0.62 in the north/south direction. The combination of temporal and spatial validation improved confidence in the model's ability to recreate realistic flow patterns. Residual currents across the entrance to the bays showed flows that move out of the bays via the upper western side and into the bays in the lower water column before surfacing on the eastern side. As the coastal current passed by headlands and islands, eddies formed in the wake of several of them. Residual flows varied among months and location along the shelf. This model is a valuable first step in understanding how particulates move through such a complex and variable nearshore region.