The Gulf of Maine has experienced pronounced changes in recent decades, including rapid warming and changes in circulation. Notably, a shift in water masses entering the Gulf occurred around 2010. Concurrent declines in critically endangered North Atlantic right whales, lobster recruitment and abundance of the foundational, subarctic copepod, Calanus finmarchicus, have designated the 2010 event as a possible regime shift. We present results from two time series stations documenting change in the mesozooplankton biomass and community composition before and after 2010. We examine both seasonal and interannual variability to elucidate potential changes in phenological drivers of the mesozooplankton population in Wilkinson Basin. Abundances of smaller copepod species increased across all seasons between the two time periods, and significantly lower abundance of late-stage C. finmarchicus was observed in late summer through winter, resulting in a decrease in mesozooplankton biomass but increases in biodiversity indices post-2010. The results highlight the contribution of ecologically important increases in chlorophyll-a concentration and warmer temperatures as drivers of mesozooplankton growth and reproduction. An important ecological influence on food availability to smaller copepods may be reduced grazing competition by late-stage C. finmarchicus, a consequence of its declined abundance due to increased predation loss and reduced advective supply.

Fish condition is an indicator of fish health, where fatter fish are generally healthier and produce more viable recruitment. Many factors may contribute to fish condition, including temperature, food availability and quality, competition and even fishing pressure. In this study, relative condition factors ( K n ) were analyzed from 1992-2023 for 50 finfish species regularly caught on the Northeast Fisheries Science Center fall bottom trawl survey. Declines in condition occurred around the year 2001 across most fish species on the Northeast US Continental Shelf, with many species recovering around 2009. These changes in condition have direct implications for fish recruitment and mortality, and may in turn impact stock assessments, catch quotas and management. Similar changepoints were found in bottom and sea surface temperatures, zooplankton anomalies and copepod size structure, potentially indicating a bottom-up regime shift. Determining relative condition changepoints along with environmental drivers has enabled stock assessments to base biological reference points on ecosystem-based time stanzas specific to the stock. Empirical dynamic modeling analyses suggest causal relationships of these environmental drivers with Atlantic mackerel and butterfish condition, further strengthening the justification of using these relationships in assessments.

The northern sand lance (Ammodytes dubius), a key species in the food web supporting the Stellwagen Bank National Marine Sanctuary (SBNMS), feeds primarily on the lipid-rich copepod Calanus finmarchicus. Climate change poses a significant threat to this dynamic, as C. finmarchicus populations are at the southern edge of their subarctic distribution and are vulnerable to warming waters and changing oceanographic conditions. Declines in the advective supply of C. finmarchicus to Stellwagen Bank could adversely affect sand lance populations and, consequently, the ecological and economic resources that depend on them. To quantify the connectivity between SBNMS and potential sources of C. finmarchicus, we used the Finite-Volume Community Ocean Model (FVCOM) coupled with Lagrangian particle tracking over the years 1978 to 2016. Numerical experiments revealed that Stellwagen Bank is highly connected to upstream areas in the Maine Coastal Current (MCC), where existing time series monitoring stations observe C. finmarchicus populations. The connectivity exhibited strong seasonal patterns, with peak connectivity occurring during spring and early summer, aligning with the sand lance feeding period on C. finmarchicus. We found significant interannual variability, influenced by changes in the strength of the MCC and circulation patterns in the western Gulf of Maine. Years with stronger MCC flow showed higher connectivity and a greater potential supply of C. finmarchicus particles to Stellwagen Bank. Conversely, periods of reduced flow corresponded with decreased connectivity, potentially limiting the availability of C. finmarchicus to sand lance populations. Meanwhile, observations from drifters and buoys since 2001 have documented decreases in MCC current speed which has been linked to a climate driven strengthening of southwesterly winds. These findings underscore the importance of pelagic habitat connectivity in assessing the climate vulnerability of marine protected areas (MPAs) like SBNMS. Furthermore, monitoring C. finmarchicus populations at upstream time series stations can provide information on downstream foraging habitat in MPAs, and potentially in other vulnerable areas of ecological and socioeconomic interest. By incorporating these indicators of connectivity and upstream C. finmarchicus population abundance into decision support tools, Sanctuary managers and stakeholders can make informed decisions to mitigate potential climate impacts.

Over the past two decades, a regional collaboration, now part of the US Marine Biodiversity Observation Network (MBON), has established the Wilkinson Basin Time Series (WBTS) and the Coastal Maine Time Series (CMTS) stations to observe change at subannual as well as multiannual scales in plankton of the western Gulf of Maine (GoM), USA. The stations are strategically located to monitor plankton in the Maine Coastal Current, a regional production driver, and in Wilkinson Basin, the primary deep basin in the western GoM. Here, we develop seasonal indices tracking change in mesozooplankton biomass and abundance of the planktonic copepod, Calanus finmarchicus, the energy-rich copepod that supports the regional ecosystem. The time series spans a shift in oceanographic conditions that occurred around 2010. In Wilkinson Basin, the abundance of C. finmarchicus varies by over an order of magnitude during its annual life cycle. At the WBTS station, the fall/winter late-stage abundance of C. finmarchicus has declined up to 80% between 2005 and 2023. The fall/winter abundance decline is likely related to a change in supply from the western Scotian Shelf after 2010 combined with increased seasonal predation mortality. However, in spring the abundance of C. finmarchicus remained steady, although initially increased after 2010. The trend in spring abundance corresponds to slight increases in chlorophyll a standing stock in late winter/early spring, favoring C. finmarchicus egg production. Similar trends in mesozooplankton biomass reflect the predominance of C. finmarchicus in the zooplankton community. We propose that the abundance cycles and trends in C. finmarchicus and biomass be reported regularly as seasonal indices, serving as a sentinel indicator of subarctic western GoM pelagic ecosystem function.

Understanding the trophic drivers of zooplankton population variability is critical for predicting ecosystem responses to climate change. In the Gulf of Maine, the copepod Calanus finmarchicus is a foundational species linking primary producers to higher trophic levels, yet the biotic drivers shaping its seasonal and interannual abundances remain incompletely understood. Here, we assess how predators impact C. finmarchicus abundances using over four decades of survey data. We find strong evidence for seasonally-structured trophic control, with spring C. finmarchicus abundances driving mid-year predator increases, which subsequently imposes significant top-down pressure on fall C. finmarchicus populations. This interplay is especially pronounced in the deep, retentive inner basins of the Gulf of Maine, where predator-prey dynamics tend to dominate over advective exchange. Our results reveal shifting interactions between bottom-up and top-down controls, highlighting the need to incorporate seasonal trophic mechanisms into ecosystem models to improve projections under further environmental change.

Copepod size and energy content are influenced by regional and seasonal variation in temperature and food conditions, with implications for planktivorous consumers such as the endangered North Atlantic right whale (Eubalaena glacialis). Historical data (1990-2020) on Calanus finmarchicus stage CV copepodite prosome length and oil sac metrics were analyzed to determine the extent of variation in individual body size and estimated lipid and energy content in five regions of the Northwest Atlantic continental shelves [Gulf of Maine (GoM), Scotian Shelf (SS), Gulf of St. Lawrence (GSL), St. Lawrence Estuary (SLE) and Newfoundland Shelf]. Large-scale spatial patterns in size and lipid content were related to latitude, indicating that C. finmarchicus CV in the GSL and SLE were historically larger in body size, and had significantly higher lipid content compared with those in the GoM and the SS. The observed patterns of C. finmarchicus CV size and lipid storage capacity suggest that regional variation in whale prey energy content can play a role in the suitability of current and future whale foraging habitats in the Northwest Atlantic, with the larger lipid-rich individuals in the GSL providing a high-quality diet compared with those in southern areas.

The timing of biological events, known as phenology, plays a key role in shaping ecosystem dynamics, and climate change can significantly alter these timings. The Gulf of Maine on the Northeast U.S. Shelf is vulnerable to warming temperatures and other climate impacts, which could affect the distribution and production of plankton species sensitive to phenological shifts. In this study, we apply a novel data-driven modeling approach to long-term datasets to understand the population variability of Calanus finmarchicus, a lipid-rich copepod that is fundamental to the Gulf of Maine food web. Our results reveal how phenology impacts the complex intermingling of top-down and bottom-up controls. We find that early initiation of the annual phytoplankton bloom prompts an early start to the reproductive season for populations of C. finmarchicus in the inner Gulf of Maine, resulting in high spring abundance. This spring condition appears to be conducive to enhanced predation pressure later in the season, consequently resulting in overall low C. finmarchicus abundance in the fall. These biologically controlled dynamics are less pronounced in the outer Gulf of Maine, where water exchanges near the boundary have a greater influence. Our analysis augments existing hypotheses in fisheries oceanography and classical ecological theory by considering unique plankton life-history characteristics and shelf sea dynamics, offering new insights into the biological factors driving C. finmarchicus variability.

Calanus finmarchicus were reared from eggs to adults at 12°C and 16°C with non‐limiting food in combination with ambient (600 μ atm) and high (1100 μ atm) p CO 2 . These conditions are likely to be encountered by the species at the southern margins of its biogeographical range by the end of the century. Dry weight (DW), carbon (C) and nitrogen (N) mass, oil‐sac volume (OSV), fatty acid composition (FA), and oxygen consumption rates (OCR) were measured on newly molted stage CV copepodites and recently molted adult females. By focusing our measurements on these precise events in the life cycle, we were able to obtain a more accurate comparison of growth and respiration across treatments. Copepods raised at 12°C had a significantly greater DW, OSV, and C and N mass than those raised at 16°C High p CO 2 , independent of temperature, was associated with a further increase in the DW and C content of the copepods. Interactive effects of temperature and p CO 2 resulted in a larger OSV at low temperature and high p CO 2 . Mass‐specific respiration rates were significantly lower at lower temperatures and elevated p CO 2 suggesting that the increase in mass (DW, C, and OSV) resulted from reduced metabolic cost. The composition of fatty acids in the copepods varied mainly with temperature. Two fatty acids varied with p CO 2 : 16:0 tended to decrease with higher p CO 2 and 18:3n−3 tended to increase with higher p CO 2 . These observations suggest that elevated p CO 2 /lower pH in future oceans may have a beneficial effect on C. finmarchicus .

The planktonic copepod Calanus finmarchicus is a fundamental prey resource for the critically endangered North Atlantic right whale Eubalaena glacialis . Incorporation of prey information into E. gla cialis decision support tools could improve management. Zooplankton time series are usually analyzed with respect to abundance, but predators such as E. glacialis forage based on whether prey aggregations exceed energetic thresholds. In order to better understand the distribution and dynamics of the high-abundance end of C. finmarchicus on the northeastern US continental shelf, where E. glacialis feed, we modeled the environmental conditions associated with C. finmarchicus densities that exceed nominal feeding thresholds. Threshold values were chosen based on a review of E. glacialis feeding behavior throughout the domain. Following model selection procedures, we used a random forest model with bathymetry, bottom temperature, bottom salinity, day of year, sea surface temperature, sea surface temperature gradient, bathymetric slope, time-integrated chlorophyll, current velocity gradient, and wind covariates. Model performance was highest with thresholds that matched reported E. glacialis feeding thresholds equivalent to 10000 copepods m -2 . The high-density aggregations of C. finmarchicus had some different covariate responses compared to previous statistical abundance models, such as a warmer temperature range at both the surface and at depth, as well as a much higher degree of spatial variability. The output data layers of the model are designed to link with E. glacialis models used in US governmental decision support tools. Including this type of foraging information in decision support tools is a step forward in managing this critically endangered species.

The lipid-rich calanoid copepod, Calanus finmarchicus, plays a critical role in the Gulf of Maine pelagic food web. Despite numerous studies over the last several decades, a clear picture of variability patterns and links with key environmental drivers remains elusive. This study applies model-based scaling and sensitivity analyses to a regional plankton dataset collected over the last four decades (1977–2017). The focus is to describe the gulf-wide spatio-temporal patterns across three major basins, and to assess the relative roles of internal population dynamics and external exchanges. For the spring stock, there is strong synchrony of interannual variability among three basins. This variability is largely driven by internal population dynamics rather than external exchanges, and the internal population dynamics are more sensitive to the change of top-down mortality regime than the bottom-up forcings. For the fall stock, the synchrony among basins weakens, and the variability is influenced by both internal mortality and external dilution loss. There appears to be no direct connection between the spring stock with either the preceding or subsequent fall stock, suggesting seasonal or sub-seasonal scales of population variability and associated drivers. The results highlight seasonally varying drivers responsible for population variability, including previously less recognized top-down control.

ful in their careers. As previously mentioned, pilot workshop participants (i.e., those involved in 2019/2020; Schiebel et al. 2021) mentioned an overwhelming interest in training on other types of communication skills beyond the scope of the pilot. Although the pilot workshops were focused on building oral presentation slides, many participants requested more practice with designing a conference poster. The focus of the 2021 workshop was poster design and presentation, which was very well received based on a 30-min informal discussion at the end of the workshop. Early career scientists may be more likely to present posters rather than talks at large conferences, so shifting gears to provide this content has been well received. Moving forward, this same content will be featured in the workshop. The original proposal was for the workshop to be fully in-person, but due to COVID-19 this in-person mode was not possible. While this move to a virtual workshop was not ideal, it was not a major setback. The biggest difficulty was accommodating the verbal sessions as these are intended to be interactive and “on your feet.” Michelle was able to pivot and create sessions that still enabled participants to interact in smaller breakout rooms and then share thoughts in the main room space. There were a few outcomes of the fully virtual space that were beneficial. First, because everyone was able to be online, multiple time zones were reached at one time. It appeared people were more comfortable asking questions using the chat feature on Zoom, presumably because most participants had already had experience with Zoom and the chat feature during the pandemic. Finally, more participants were engaged than in the pilot workshops. In previous years, approximately 40 of 50 slots were filled onsite, vs. 53 participants in the 2021 virtual session. We still feel that an inperson workshop is the best environment for the delivery of this material, but the alternate fully remote option was highly successful. For future workshops we are exploring the option of a twoday workshop with virtual poster creation sessions on the first day a few weeks before the conference, and then a second day focused on inperson poster presentation. This would allow for participants to: (1) not be overwhelmed by receiving all the content in one day, and (2) harness the potential of both virtual and in-person professional development. The workshop team feels strongly that the shift in content from slide to poster design along with the move to a virtual environment in light of COVID-19 created a successful workshop based on survey and informal participant feedback. We have plans to continue with virtual engagement in some form for coming workshops.

Abstract Marine Life 2030 is a program to establish the globally coordinated system to deliver actionable, transdisciplinary knowledge of ocean life to those who need it, promoting human well-being, sustainable development, and ocean conservation (Figure 1). The diversity of marine habitats and species is fundamental for human survival. Biodiversity provides opportunities for multiple fisheries, the tourism industry, and harbor medicines and materials. The Marine Biodiversity Observation Network (MBON) is the platform to build the community of practice to implement Marine Life 2030. MBON fosters collaborations to coordinate collection, sharing, and application of biodiversity information. Benefits of joining MBON include expanded capacity to address research goals, leveraging resources and best practices; linking natural and social sciences to answer policy questions; engaging diverse and early-career researchers; and addressing issues of concern to humanity.

The American sand lance (Ammodytes americanus, Ammodytidae) and the Northern sand lance (A. dubius, Ammodytidae) are small forage fishes that play an important functional role in the Northwest Atlantic Ocean (NWA). The NWA is a highly dynamic ecosystem currently facing increased risks from climate change, fishing and energy development. We need a better understanding of the biology, population dynamics and ecosystem role of Ammodytes to inform relevant management, climate adaptation and conservation efforts. To meet this need, we synthesized available data on the (a) life history, behaviour and distribution; (b) trophic ecology; (c) threats and vulnerabilities; and (d) ecosystem services role of Ammodytes in the NWA. Overall, 72 regional predators including 45 species of fishes, two squids, 16 seabirds and nine marine mammals were found to consume Ammodytes. Priority research needs identified during this effort include basic information on the patterns and drivers in abundance and distribution of Ammodytes, improved assessments of reproductive biology schedules and investigations of regional sensitivity and resilience to climate change, fishing and habitat disturbance. Food web studies are also needed to evaluate trophic linkages and to assess the consequences of inconsistent zooplankton prey and predator fields on energy flow within the NWA ecosystem. Synthesis results represent the first comprehensive assessment of Ammodytes in the NWA and are intended to inform new research and support regional ecosystem-based management approaches.

IntroductionCurrent methods of intraoperative margin assessment in breast conserving surgery are impractical, unreliable, or time consuming. We hypothesized that intraoperative near-infrared (NIR) imaging with an FDA-approved NIR optical contrast agent could identify canine mammary tumors, a spontaneous large animal model of human breast cancer, during surgery.MethodsDogs with mammary tumors underwent a standard of care lumpectomy or mastectomy with wide surgical margins 20 hours after indocyanine green administration (3 mg/kg IV). During surgery, NIR imaging was performed on tumors and wound margins in situ and tumors and lymph nodes ex vivo. Following resection, the wound bed was examined for residual fluorescence. Fluorescence intensity was determined by signal-to-background ratio (SBR). All tumors, areas of residual fluorescence, and lymph nodes underwent histopathologic analysis.ResultsThere were 41 mammary tumors in 16 female dogs. Twenty tumors were malignant and 21 were benign. Twenty-eight tumors were fluorescent (mean SBR 1.5±0.2). Sensitivity of fluorescence for all malignant tumors was 80% (16/20) and 93.3% (14/15) for malignant tumors > 2 cm. Specificity for malignancy was low (< 2cm = 55%; > 2cm = 30%). Tumors > 2 cm were more likely to be fluorescent (OR 6.05, 95% CI 1.50-24.44, P = 0.011) but not more likely to be malignant (OR 3.09, 95% CI 0.86-11.14, P = 0.085) than tumors ≤ 2 cm. Four out of seven inguinal lymph nodes excised in the mastectomy specimen fluoresced. All four drained malignant tumors; however only 2/4 contained metastatic disease.ConclusionSystemic ICG accumulates reliably in malignant canine mammary tumors > 2 cm. Although no tumor margins fluoresced, a wider margin of normal tissue is removed in canine mastectomy, making direct comparisons with breast conserving surgery difficult. Targeted NIR imaging agents are likely required to improve detection of smaller tumors and improve the specificity of NIR imaging for residual disease and metastatic lymph node detection.

As climate trends accelerate, ecosystems will be pushed rapidly into new states, reducing the potential efficacy of conservation strategies based on historical patterns. In the Gulf of Maine, climate-driven changes have restructured the ecosystem rapidly over the past decade. Changes in the Atlantic meridional overturning circulation have altered deepwater dynamics, driving warming rates twice as high as the fastest surface rates. This has had implications for the copepod Calanus finmarchicus, a critical food supply for the endangered North Atlantic right whale (Eubalaena glacialis). The oceanographic changes have driven a deviation in the seasonal foraging patterns of E. glacialis upon which conservation strategies depend, making the whales more vulnerable to ship strikes and gear entanglements. The effects of rapid climate-driven changes on a species at risk undermine current management approaches.

The copepod Lepeophtheirus salmonis is an obligate ectoparasite of salmonids. Salmon lice are major pests in salmon aquaculture and due to its economic impact Lepeophtheirus salmonis is one of the most well studied species of marine parasite. However, there is limited understanding of how increased concentration of pCO2 associated with ocean acidification will impact host-parasite relationships. We investigated the effects of increased pCO2 on growth and metabolic rates in the planktonic stages, rearing L. salmonis from eggs to 12 days post hatch copepodids under three treatment levels: Control (416 µatm), Mid (747 µatm), and High (942 µatm). The pCO2 treatment had a significant effect on oxygen consumption rate with the High treatment animals exhibiting the greatest respiration. The treatments did not have a significant effect on the other biological endpoints measured (carbon, nitrogen, lipid volume, and fatty acid content). The results indicate that L. salmonis have mechanisms to compensate for increased concentration of pCO2and that populations will be tolerant of projected future ocean acidification scenarios. The work reported here also describes catabolism during the lecithotrophic development of L. salmonis, information that is not currently available to parameterize models of dispersal and viability of the planktonic free-living stages.

Fluorescence guided surgery is an emerging technology that may improve accuracy of pulmonary resection for non-small cell lung cancer (NSCLC). Herein we explore optical imaging for NSCLC surgery using the well-studied protoporphyrin IX (PPIX)/5-aminiolevulinic acid (5-ALA) system. More specifically, we evaluate fluorescent patterns observed when using (1) commonly utilized in vitro and murine NSCLC models and with (2) spontaneous canine NSCLCs, which closely mimic human disease. Using flow cytometry and fluorescent microscopy, we confirmed that NSCLC models fluoresce after exposure to 5-ALA in vitro. High levels of fluorescence were similarly observed in murine tumors within 2 hours of systemic 5-ALA delivery. When evaluating this approach in spontaneous canine NSCLC, tumor fluorescence was observed in 6 of 7 canines. Tumor fluorescence, however, was heterogenous owing to intratumoral variations in cellularity and necrosis. Margin and lymph node detection was inaccurate. These data demonstrate the importance of incorporating reliable cancer models into preclinical evaluations of optical agents. Utilization of spontaneous large animal models of cancer may further provide an important intermediate in the path to human translation of optical contrast agents.

The North Atlantic right whale (NARW), Eubalaena glacialis, feeds on zooplankton, particularly copepods of the genus Calanus. We quantified interannual variation in anomalies of abundance and biomass of Calanus spp. and near-surface and near-bottom ocean temperature and salinity from 19 subregions spanning the Gulf of Maine–Georges Bank (GoM–GBK), Scotian Shelf (SS), Gulf of St. Lawrence (GSL) and Newfoundland and Labrador Shelves. We analyzed time series from 1977 to 2016 in GoM–GBK, 1982 to 2016 in southwest GSL and 1999 to 2016 in remaining areas. Calanus finmarchicus dominated abundance and biomass, except in the GSL where Calanus hyperboreus was abundant. The biomass of Calanus spp. declined in many subregions over years 1999–2016 and was negatively correlated with sea surface temperature in GoM–GBK and on the SS. We detected ``regime shifts” to lower biomass of Calanus spp. in the GoM–GBK in 2010 and on the SS in 2011. In the GoM–GBK, shifts to lower biomass of C. finmarchicus coincided with shifts to warmer ocean temperature and with published reports of changes in spatial distribution and reduced calving rate of NARW. We hypothesize that warming has negatively impacted population levels of Calanus spp. near their southern range limit, reducing the availability of prey to NARW.

Copepods of the genus Calanus play a critical trophic role in the North Atlantic ecosystems, where they serve as an important source of energy-rich food for fish and marine mammals, including the endangered North Atlantic right whale. As a strategy for coping with unfavorable near-surface conditions, Calanus enter diapause and migrate to deep water in late summer and fall after feeding and accumulating lipid stores in spring and summer. In order to assess the most important physical drivers of vertical distribution of diapausing Calanus, we synthesized existing depth-stratified abundance data of Calanus finmarchicus and Calanus hyperboreus from the Northwest Atlantic continental shelf and slope regions, spanning Newfoundland in the northeast to the Gulf of Maine in the southwest. Bottom depth strongly constrained the depth and shape of vertical distributions, with distributions becoming deeper and less compact as bottom depth increased. Diapausing Calanus, observed across a broad range of temperature (T) and in-situ density (sigma) conditions (T = -1.0 to 14.4 degrees C, a = 25.3-28.1 kg m(-3)), tended to distribute at depths with the coldest temperatures locally available. Over the shelf, diapausing Calanus in the GOM and SS generally did not have access to temperatures considered optimal for diapause ( < 5 degrees C), in many cases occurring at temperatures well above this threshold. Diapausing Calanus in both habitats were most commonly below the Cold Intermediate Layer (CIL), a feature formed through wind-driven mixing during the winter, but this effect was more obvious over the shelf than in slope waters. Our analysis highlights key differences in the vertical distributions of diapausing Calanus over the shelf vs. the slope, having regional implications for ecological dynamics and population persistence in the face of warming temperatures. In general, understanding factors that influence vertical distributions of diapausing Calanus will allow us to more accurately predict how the environmental conditions they encounter while overwintering may shift during climate change, which has implications for survival through diapause, and consequently, shelf-wide population dynamics.