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Multispecies models have existed in a fisheries context since at least the 1970s, but despite much exploration, advancement, and consideration of multispecies models, there remain limited examples of their operational use in fishery management. Given that species and fleet interactions are inherently multispecies problems and the push towards ecosystem-based fisheries management, the lack of more regular operational use is both surprising and compelling. We identify impediments hampering the regular operational use of multispecies models and provide recommendations to address those impediments. These recommendations are: (1) engage stakeholders and managers early and often; (2) improve messaging and communication about the various uses of multispecies models; (3) move forward with multispecies management under current authorities while exploring more inclusive governance structures and flexible decision-making frameworks for handling tradeoffs; (4) evaluate when a multispecies modelling approach may be more appropriate; (5) tailor the multispecies model to a clearly defined purpose; (6) develop interdisciplinary solutions to promoting multispecies model applications; (7) make guidelines available for multispecies model review and application; and (8) ensure code and models are well documented and reproducible. These recommendations draw from a global assemblage of subject matter experts who participated in a workshop entitled “Multispecies Modeling Applications in Fisheries Management”.

The complexities of ecosystem-based management require stepwise approaches, ideally involving stakeholders, to scope key processes, pressures, and impact in relation to sustainability and management objectives. Use of qualitative methods like Fuzzy Cognitive Mapping (FCM) with a lower skill and data threshold than traditional quantitative models afford opportunity for even untrained stakeholders to evaluate the present and future status of the marine ecosystems under varying impacts. Here, we present the results applying FCM models for subregions of the North Sea. Models for the southern North Sea, Skagerrak, Kattegat, and the Norwegian Trench were developed with varying level of stakeholder involvement. Future scenarios of increased and decreased fishing, and increased seal biomass in the Kattegat, were compared with similar scenarios run on two quantitative ecosystem model. Correspondence in response by the models to the same scenarios was lowest in the southern North Sea, which had the simplest FCM model, and highest in Norwegian Trench. The results show the potential of combining FCM and quantitative modelling approaches in integrated ecosystem assessments (IEAs) and in future ecosystem-based management advice, but to facilitate such comparisons and allow them to complement and enhance our IEAs, it is important that their components are aligned and comparable.

The ability to synchronise is a hallmark of professional music-making. Such synchronisation, without a conductor, is achievable by timing error correction, either through phase correction (Wing et al., 2014) or period correction (by adjusting the timekeeper interval; Schulze et al., 2005). Here we investigate how an ensemble employs such inter-personal adjustment of micro-scale timings to maintain synchronisation even whilst applying tempo changes associated with expressive musical interpretation. We invited the Coull Quartet to perform a Haydn excerpt in three different ways: 1) minimal temporal expression (‘deadpan’), 2) ‘normal’ expression, 3) accelerando followed by rallentando. Leadership was assigned either to the first or second violin. Using linear and bounded generalised least squares (Jacoby et al., 2015) models of sensorimotor synchronisation, we estimated correction gain parameters for phase and period correction. Results suggested that the Coull Quartet tended towards a more democratic rather than hierarchical approach to group synchronisation. Interestingly, period correction was evident only when tempo changes were introduced into the performance, whereas phase correction was employed throughout, even during the ‘deadpan’ trials. These findings will help to develop interactive training tools for student chamber musicians.

We present a plug-in for music production software (i.e., digital audio workstations) that simulates musicians synchronizing to other musicians, either virtual or controlled by users. Notes of the parts controlled by users are played according to MIDI input (e.g., a drum pad). Notes associated with virtual musicians are played according to a linear phase correction model, where the time of the next note of each part is produced in weighted proportion to the asynchrony of the previous note and the notes of each of the other parts. Each virtual musician’s performance is controlled by: two noise parameters defining the variability of central timer and motor implementation processes (Wing and Kristofferson 1973); a delay parameter, defining the variability in lag to play a note; and a set of alpha parameters, defining the correction to the asynchrony to other players (both human and machine). These parameters can differ between musicians and can be adjusted in real-time. The number of musicians can be configured allowing studies involving any mixture of virtual and human players. The plugin has been tested with the homophonic part of a Haydn piece with three virtual musicians and one user. Event times are logged to study ensemble synchronisation. The plug-in will be used as part of an interactive augmented reality ensemble (https://arme-project.ac.uk). Wing, A.M., Endo, S., Bradbury, A. and Vorberg, D., 2014. Optimal feedback correction in string quartet synchronization. Journal of The Royal Society Interface, 11(93), p.20131125.

Recent work in note onset detection has centered on deep learning models such as recurrent neural networks (RNN), convolutional neural networks (CNN) and more recently temporal convolutional networks (TCN), which achieve high evaluation accuracies for onsets characterized by clear, well-defined transients, as found in percussive instruments. However, onsets with less transient presence, as found in string instrument recordings, still pose a relatively difficult challenge for state-of-the-art algorithms. This challenge is further exacerbated by a paucity of string instrument data containing expert annotations. In this paper, we propose two new models for onset detection using bidirectional temporal and recurrent convolutional networks, which generalise to polyphonic signals and string instruments. We perform evaluations of the proposed methods alongside state-of-the-art algorithms for onset detection on a benchmark dataset from the MIR community, as well as on a test set from a newly proposed dataset of string instrument recordings with note onset annotations, comprising approximately 40 minutes and over 8,000 annotated onsets with varied expressive playing styles. The results demonstrate the effectiveness of both presented models, as they outperform the state-of-the-art algorithms on string recordings while maintaining comparative performance on other types of music.

Three pelagic stocks in the Baltic Sea, Central Baltic Herring (CBH; her.27.25-2932), Sprat (spr.27.22-32) and Gulf of Riga Herring (GOR, her 27.28) were examined during this benchmark. Work was prepared well in advance and 3 preparatory online meetings took place between the Data Evaluation Workshop and the actual benchmark to follow up progress. The benchmark meeting advanced really well until reference points were discussed. There were follow up online meetings on 3rd and 13th March to further discuss, and agree, on reference points for the three stocks. All three stocks that was benchmarked were previously assessed with XSA, and hence a main point with the benchmark was to change the assessment model. Two of the stocks changed to SAM (GOR and sprat) whereas the CBH changed to stock synthesis (SS3). For the GOR and sprat the reference points were estimated following the ICES procedure using EQSIM. For the CBH the reference points were obtained using a Management strategy evaluations (MSE), a method previously used for one of the Northern shrimps stocks in ICES (pra.27.3a4a). There was an extensive issue list for the CBH and although not all of the issues were addressed, significant progress was made. Additional survey indices, maturity at age, weight in catch, adding age reading error, landings corrected for misreporting (Danish landings only) were all investigated and updated time series were included in the new assessment. SS3 was chosen as main assessment method and there was extensive model development work carried out in advance and presented at the meeting. An ensemble model was developed to incorporate uncertainty in natural mortality. Three scenarios of natural mortalities were developed from rescaling the natural mortalities from a multispecies model for the Baltic (SMS) with life history parameters. An objective weighing approach was used based on model performance statistics diagnostics to develop the final assessment.