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Ecological research and monitoring need to be able to rapidly convey information that can form the basis of scientifically sound management. Automated sensor systems, especially if combined with artificial intelligence, can contribute to such rapid high-resolution data retrieval. Here, we explore the prospects of automated methods to generate insights for seabirds, which are often monitored for their high conservation value and for being sentinels for marine ecosystem changes. We have developed a system of video surveillance combined with automated image processing, which we apply to common murres Uria aalge. The system uses a deep learning algorithm for object detection (YOLOv5) that has been trained on annotated images of adult birds, chicks and eggs, and outputs time, location, size and confidence level of all detections, frame-by-frame, in the supplied video material. A total of 144 million bird detections were generated from a breeding cliff over three complete breeding seasons (2019–2021). We demonstrate how object detection can be used to accurately monitor breeding phenology and chick growth. Our automated monitoring approach can also identify and quantify rare events that are easily missed in traditional monitoring, such as disturbances from predators. Further, combining automated video analysis with continuous measurements from a temperature logger allows us to study impacts of heat waves on nest attendance in high detail. Our automated system thus produces comparable, and in several cases significantly more detailed, data than those generated from observational field studies. By running in real time on the camera streams, it has the potential to supply researchers and managers with high-resolution up-to-date information on seabird population status. We describe how the system can be modified to fit various types of ecological research and monitoring goals and thereby provide up-to-date support for conservation and ecosystem management.

1. Timing of breeding, an important driver of fitness in many populations, is widely studied in the context of global change, yet despite considerable efforts to identify environmental drivers of seabird nesting phenology, for most populations we lack evidence of strong drivers. Here we adopt an alternative approach, examining the degree to which different populations positively covary in their annual phenology to infer whether phenological responses to environmental drivers are likely to be (i) shared across species at a range of spatial scales, (ii) shared across populations of a species, or (iii) idiosyncratic to populations. 2. We combined 51 long-term datasets on breeding phenology spanning 50 years from nine seabird species across 29 North Atlantic sites and examined the extent to which different populations share early versus late breeding seasons depending on a hierarchy of spatial scales comprising breeding site, small-scale region, large-scale region and the whole North Atlantic. 3. In about a third of cases we found laying dates of populations of different species sharing the same breeding site or small-scale breeding region were positively correlated, which is consistent with the hypothesis that they share phenological responses to the same environmental conditions. In comparison we found no evidence for positive phenological covariation among populations across species aggregated at larger spatial scales. 4. In general we found little evidence for positive phenological covariation between populations of a single species, and in many instances the inter-year variation specific to a population was substantial, consistent with each population responding idiosyncratically to local environmental conditions. Black-legged kittiwake (Rissa tridactyla) was the exception, with populations exhibiting positive covariation in laying dates that decayed with the distance between breeding sites, suggesting that populations may be responding to a similar driver. 5. Our

Density-dependent prey depletion around breeding colonies has long been considered an important factor controlling the population dynamics of colonial animals. Ashmole proposed that as seabird colony size increases, intraspecific competition leads to declines in reproductive success, as breeding adults must spend more time and energy to find prey farther from the colony.1 Seabird colony size often varies over several orders of magnitude within the same species and can include millions of individuals per colony. As such, colony size likely plays an important role in determining the individual behavior of its members and how the colony interacts with the surrounding environment.6 Using tracking data from murres (Uria spp.), the world’s most densely breeding seabirds, we show that the distribution of foraging-trip distances scales to colony size0.33 during the chick-rearing stage, consistent with Ashmole’s halo theory.1,2 This pattern occurred across colonies varying in size over three orders of magnitude and distributed throughout the North Atlantic region. The strong relationship between colony size and foraging range means that the foraging areas of some colonial species can be estimated from colony sizes, which is more practical to measure over a large geographic scale. Two-thirds of the North Atlantic murre population breed at the 16 largest colonies; by extrapolating the predicted foraging ranges to sites without tracking data, we show that only two of these large colonies have significant coverage as marine protected areas. Our results are an important example of how theoretical models, in this case, Ashmole’s version of central-place-foraging theory, can be applied to inform conservation and management in colonial breeding species.

The Razorbill Alca torda is one of three auk species breeding in Sweden, often occurring in colonies with Common Guillemot Uria aalge. The largest colony in the Baltic Sea is situated on the island Stora Karlsö west of Gotland. During the chick-rearing phase, Razorbills forage at sea and return to feed the young with single or multiple prey carried sideways in the bill, unlike Common Guillemots that carry a single fish in the middle of the bill. Clupeids, especially sprat Sprattus sprattus, are the main prey of Baltic Sea Razorbills, but studies are scarce. Here, we investigate the diet preference of Razorbills at Stora Karlsö with regard to prey taxonomy and size, analysing photographs and applying morphometric equations. We show that most feeding attempts involved a single clupeid (88% of known fish taxonomy), in most cases likely sprat. The average prey size (115 mm) and prey species was similar to that of Common Guillemots in the same colony. The variation in size was much smaller in the Razorbill diet than the size distribution of clupeids at sea, indicating a strong prey size selectivity. The Razorbills’ high specialisation underlines the importance of maintaining strong populations of clupeids in their foraging area, as these fish are also targeted by industrial fisheries.

Forage fish populations often undergo large and rapid fluctuations in abundance. However, most of their predators are buffered against such fluctuations owing to their slower pace of life, which allows them to maintain more stable populations, at least during short periods of food scarcity. In this study, we investigated top‐down processes exerted by seabirds on forage fish stocks in five contrasted marine ecosystems, compiling numerous data sets on seabird counts, diets, energetic needs and prey energy content and abundance. Off Norway, South Africa, Peru, Sweden and Scotland, we found that predation pressure—estimated as the proportion of a fish stock consumed by seabirds—was generally low (median = 1%), but increased sharply at low levels of prey abundance. When prey biomass decreased below 15–18% of its maximum recorded value, predation by seabirds became a source of important additional pressure on prey stocks (~20% of prey biomass is consumed by seabirds). An earlier empirical study advocated for keeping forage stocks from falling below a threshold of 33% of long‐term maximum prey biomass in order to safeguard seabird breeding success, but here we further suggest that a threshold of 18% should be considered as a limit not to be exceeded for the sake of the forage fish themselves, and below which extra cautious management of fisheries may be required. Nevertheless, despite exceptionally high rates of predation on some occasions, predation pressure was not correlated with prey dynamics, suggesting an absence of prey entrapment due to seabirds alone in these five ecosystems.

Anoxic zones, regions of the water column completely devoid of dissolved oxygen, occur in open oceans and coastal zones worldwide. The Baltic Sea is characterized by strong salinity-driven stratification, maintained by occasional water inflows from the Danish Straights and freshwater input from rivers. Between inflow events, the stratification interface between surface and deep waters hinders mixing and ventilation of deep water; consequently, the bottom waters of large regions of the Baltic are anoxic. The onset of the anoxic zone is closely coincident with the depth of the halocline and, as a result, the interface between oxic and anoxic waters corresponds to a strong impedance contrast. Here, we track acoustic scattering from the impedance contrast utilizing a broadband split-beam echosounder in the Western Gotland Basin and link it to a dissolved oxygen level of 2ml/l using ground truth stations. The broadband acoustic dataset provides the means to remotely observe the spatiotemporal variations in the oxic-anoxic interface, map out the extent of the anoxic zone with high resolution, and identify several mechanisms influencing the vertical distribution of oxygen in the water column. The method described here can be used to study other systems with applications in ongoing oceanographic monitoring programs.

This report presents a review of the research knowledge and gaps on fish populations, fisheries and linked ecosystems in the Central Arctic Ocean (CAO). The CAO comprises the deep basins of the Arctic Ocean beyond the shelf break, which largely overlap with the High Seas of the Arctic Ocean, i.e. the marine areas outside the Exclusive Economic Zones (EEZs) of the Arctic coastal nations. The authors of the report are members of the European Fisheries Inventory in the Central Arctic Ocean (EFICA) Consortium. This study was funded by the European Commission as an EU contribution to the international cooperation within the Agreement to Prevent Unregulated High Seas Fisheries in the Central Arctic Ocean.

The concept of “blue growth,” which aims to promote the growth of ocean economies while holistically managing marine socioecological systems, is emerging within na-tional and international marine policy. The concept is often promoted as being novel; however, we show that historical analogies exist that can provide insights for contem-porary planning and implementation of blue growth. Using a case-study approach based on expert knowledge, we identified 20 historical fisheries or aquaculture ex-amples from 13 countries, spanning the last 40–800 years, that we contend embody blue growth concepts. This is the first time, to our knowledge, that blue growth has been investigated across such broad spatial and temporal scales. The past societies managed to balance exploitation with equitable access, ecological integrity and/or economic growth for varying periods of time. Four main trajectories existed that led to the success or failure of blue growth. Success was linked to equitable rather than open access, innovation and management that was responsive, holistic and based on scientific knowledge and monitoring. The inability to achieve or maintain blue growth resulted from failures to address limits to industry growth and/or anticipate the im-pacts of adverse extrinsic events and drivers (e.g. changes in international markets, war), the prioritization of short-term gains over long-term sustainability, and loss of supporting systems. Fourteen cross-cutting lessons and 10 recommendations were derived that can improve understanding and implementation of blue growth. Despite the contemporary literature broadly supporting our findings, these recommenda-tions are not adequately addressed by agendas seeking to realize blue growth.

Many natural resources have degraded and collapsed despite being managed under rigorous institutional frameworks set up to ensure rational exploitation. Path dependency of dysfunction institutions has been suggested as an explanation for such undesired outcomes. We explore the role of path dependency in natural resource management by studying a 100-year evolution of Swedish fisheries. We rely on three main types of original longitudinal data collected for the period 1914-2016: (A) policy documents, (B) government spending on management and subsidies, and (C) catch and fleet data. Our analysis contrasts the periods before and after the Swedish entrance into the European Union (1995) because this marks the year when fisheries policy became beyond the direct influence of the Swedish government. We uncover four pieces of evidence suggesting the existence of a path dependent dynamic in the pre-EU period: (1) despite increasing insights on the vulnerability of fish stocks to overexploitation, national policy goals in relation to fisheries continuously promoted incompatible goals of social and economic growth but without any reference to the sustainability of the biological resources; (2) the same policy instruments were used over long periods; (3) actor constellations within the fisheries policy subsystem were stable over time; (4) neither political regime nor macroeconomic variables and fisheries performance (industry production, oil price, landing values) could explain observed temporal variation in subsidies. We conclude that key policy actors in the pre-EU period formed an iron triangle and thereby prevented necessary policy changes. These national reinforcing feedbacks have been weakened since EU entrance, and the indicators for path dependency show broader involvement of stakeholders, a shift in spending, and policy goals that now explicitly address ecological sustainability.

Rising inequalities and accelerating global environmental change pose two of the most pressing challenges of the twenty-first century. To explore how these phenomena are linked, we apply a social-ecological systems perspective and review the literature to identify six different types of interactions (or pathways) between inequality and the biosphere. We find that most of the research so far has only considered one-directional effects of inequality on the biosphere, or vice versa. However, given the potential for complex dynamics between socioeconomic and environmental factors within social-ecological systems, we highlight examples from the literature that illustrate the importance of cross-scale interactions and feedback loops between inequality and the biosphere. This review draws on diverse disciplines to advance a systemic understanding of the linkages between inequality and the biosphere, specifically recognizing cross-scale feedbacks and the multidimensional nature of inequality.

Sustainable fisheries management plays a critical role in supporting healthy marine ecosystems and the livelihoods of millions of people. An emerging view on fisheries management emphasizes the need to manage fisheries as complex social-ecological systems. Yet, our understanding of the outcomes of fisheries management from a social-ecological perspective is limited in comparison to that provided by either the biophysical or the social perspective alone. In the Baltic Sea, management interventions focused on ecosystem recovery contributed to unintended changes from 1996 to 2009 in the fishing strategy diversity practiced by Swedish fishers. We evaluate how the changes in strategy diversification affected the capacity of Swedish fishers to adapt to future ecosystem changes. To do this, we constructed and analyzed social-ecological fisheries networks. Our analysis confirmed the previously reported development of a narrower combination of fishing strategies among large-scale fishers, parallel with a diversification in small-scale fishers' strategies. However, the results demonstrated that switching fishing strategies has, in fact, increased in magnitude, and the fishers were more equally distributed in different fishing strategies in 2009 than in 1996. Further, we detected a development toward lower ecological dependency between fishing strategies within the community, although the strategies remained connected through ecological interactions. In conclusion, our analysis of the social-ecological interdependencies suggests that the previously reported changes in the fishing strategy diversity increased the adaptability of the Swedish Baltic Sea fishers to changing ecological conditions. On the other hand, the changes may have made the Baltic Sea more vulnerable to poor management. This empirical study emphasizes the importance of a social-ecological approach on fisheries research and management. Our results show that appreciating the complexity and changing nature of fis

We studied the at-sea distribution of two auks (Common Murre Uria aalge, Razorbill Alca torda), two gulls (Lesser Black-backed Gull Larus fuscus, Herring Gull Larus argentatus), and Great Cormorant Phalacrocorax carbo during the peak breeding season of 2014 around Stora Karlso, the main Baltic Sea seabird colony. Simultaneously, we quantified forage fish abundance and distribution using hydro-acoustics and pelagic trawling. The auks and gulls had a roughly similar distribution, foraging mainly about 40 km west-northwest from the colony. Great Cormorants were found only in inshore areas, close to the colony. Sprat Sprattus sprattus and herring Clupea harengus biomass was, respectively, 1.38 and 2.68 mt/km(2) averaged over the whole study area. These estimates represent a total biomass for small pelagic fish of 17 900 t in the 4 408 km(2) study area. The estimated prey consumption over the breeding season was 2 310 t for Common Murre and Razorbill combined. Thus, auks may have a non-negligible impact on their prey sources in the region. Common Murres foraged closer to the colony (median 36.3 km) than Razorbills (median 41.1 km), but we found no significant correlation between auk at-sea numbers and fish densities. We discuss how new technology can contribute to detailed monitoring of the interactions between seabirds and fish at different spatial and temporal scales, with the ultimate aim of providing a scientific basis for ecosystem-based management.

The ecosystem approach is a salient policy paradigm originating from a scientific understanding of the reality of complex ecosystem dynamics. In this article, we investigate how Swedish national marine policies and practice between 2002 and 2015 have changed towards an ecosystem approach. Government documents, the scientific literature, institutional changes, changes in legislation, pilot projects, and changes in science and public opinion were reviewed and combined with information from expert interviews. We found that changes in policy and practice have slowly stimulated the development of an ecosystem approach, but that limited political leadership, challenges of coordination, different agency cultures, and limited learning appears to be key barriers for further and more substantial change. We compare and contrast the Swedish national process of change with other documented experiences of implementing an ecosystem approach and find that several countries struggle with similar challenges. Substantial work still remains in Sweden and we provide suggestions for how to stimulate further and more substantial change at the national level.

I rapporten kan du ta del av bedömningen som görs av situationen för bestånd som regleras inom ramen för EU:s gemensamma fiskeripolitik (GFP). Bedömningarna baseras på det forskningssamarbete och den rådgivning som sker inom det Internationella Havsforskningsrådet (ICES). De bestånd som förvaltas nationellt baseras på de biologiska underlagen, och rådgivningen i huvudsak på den forskning och övervakning samt analys som bedrivs av Institutionen för akvatiska resurser vid Sveriges lantbruksuniversitet (SLU Aqua) samt yrkesfiskets rapportering. Rapporten omfattar 41 fiskarter och sju skaldjursarter. Nytt för i år är att vi även beskriver fritidsfisket mer utförligt. Det fisket får allt större betydelse för utvecklingen av många av Sveriges bestånd av fisk- och skaldjur, till exempel sötvattens- och kustlevande arter som abborre, gädda, gös, lax, röding och öring, liksom marina arter som torsk och hummer Översikten är utarbetad av SLU Aqua på uppdrag av Havs- och vattenmyndigheten.