• Acronym: WG-56
• Parent Committee: BIO
• Established: PICES-2025
  (GC Decision 2025/S/13)
• Duration: PICES-2025 - PICES-2028
  
• Mailing List

Seamount ecosystems are patchily distributed communities associated with deep bathymetric features. Broad array of taxa inhabit these ecosystems. Adequate influx of new individuals is required for population maintenance or recovery of impacted ecosystems. Many marine taxa have dispersive propagules which temporarily inhabit the water column away from benthic adult habitat. Propagules from one location may potentially colonize the same location as well as other locations depending on ocean currents and larval ecology. This WG seeks to better understand this process by applying connectivity modelling to seamount ecosystems using best available scientific knowledge. Mapping sources, pathways, and destinations of propagules will characterize interconnectedness of seamount networks. Certain locations may be disproportionately larger sources of propagules over others, and this knowledge can improve management.

Ecological knowledge for many seamount taxa is sparse. The WG’s first work component will be to assimilate scientific data on seamount ecosystem taxa pertinent to propagule transport. This could include, but is not limited to, timing and location of spawning, type of propagule, pelagic larval duration, larval behavior, settlement cues, environmental dependencies.

Physical oceanography around seamounts is difficult to resolve given fine scale processes around abrupt seafloor features. Review and synthesis of prior deep connectivity modelling will be accomplished. This information will help establish best practices for characterizing flow fields around seamounts and using such circulation data for particle transport modelling. Available circulation models will be explored and downscaling may be applied if deemed necessary. This will be the WG’s second work component.

The Working Group’s final work component will be using the biological and physical data to run biophysical connectivity modelling for selected seamounts in the North Pacific as a proof of concept. It is anticipated that this new working group will lay the foundation for a global examination of seamount connectivity.

This working group aligns with PICES Strategic Plan by fostering international collaboration among experts in seamount ecosystems, physical oceanography, biophysical modeling (Goal 1). Leveraging this expertise to better understanding larval supply dynamics to seamount ecosystems will help characterize their vulnerability and resilience (Goal 2). A primary goal of this working group is to better understand how seamount ecosystems respond to environmental forcings at multiple temporal scales (Goal 3). The quantitative methodology utilized (deep sea Lagrangian particle tracking along isopycnals in ensemble framework) will provide new tools to better understand physical forcings on ecosystems (Goal 4). This working group will promote open data-sharing practices and ensure accessibility and circulation of scientific information (Goal 5). This working group will support early-career scientists by requiring ECOP membership as part of its structure (Goal 6). This working group will foster global scientific cooperation and contributes to sustainable marine ecosystems in the North Pacific.

Linkage(s) to Previous PICES Expert Groups Activities
This proposed working group builds upon the work of PICES WG 47 (Ecology of Seamounts), which focused broadly on seamount ecosystem science. By expanding into deep sea connectivity, a specific topic highlighted by the WG 47 final report, this working group will further efforts to better understand seamount ecosystem vulnerability and resilience.

Linkage(s) to Other Organizations and Programs
North Pacific Fisheries Commission (NPFC): The theme of this working group is recognized as critically important by the Scientific Committee (SC) of the NPFC as well as multiple NPFC SC subsidiary bodies such as the Small Scientific Committee on Bottom Fish and Marine Ecosystems (SSC-BFME), Small Working Group on Vulnerable Marine Ecosystems (SWG VME), and Small Working Group on North Pacific Armorhead and Splendid Alfonsino (SWG NPA-SA).

Terms of Reference

1. Review existing biological information of seamount taxa relevant to propagule transport modeling.
2. Review existing studies on deep sea connectivity, inventory ocean circulation models for suitability, and develop best practices for seamount connectivity modeling. This could include downscaling of existing circulation model output.
3. Apply connectivity modeling to selected seamounts in the North Pacific as a proof of concept.
4. Foster collaboration between ecosystem biologists and physical oceanographers, build scientific capacity via ECOP engagement in WG.
5. Organize workshops and symposia sessions to disseminate findings and enhance capacity building.
6. Produce a PICES final report summarizing the literature review, best practices for connectivity modeling, and results of the application to selected seamounts of the North Pacific. Peer-reviewed publication(s) will be part of this TOR with quantity and scope of such to be determined during the course of this WG.

Time Line and Expected Deliverables
Year 1 (2026)

1. WG meeting (Zoom meeting in early 2026 after approval of WG)
   • Discuss schedules, plans, and contributors for terms of reference and deliverables
   • Discuss logistics of intersessional and asynchronous progress
   • Discuss roster of WG, recruitment
   • Discuss subgroups and subject matter expert teams, recruitment
2. WG hybrid meeting (mid 2026)
   • Summarize progress
   • Establish subgroups for biological, physical, connectivity
   • Establish subject matter expert teams
   • Develop work plan for subgroups
   • Discuss schedules and plans of symposium sessions and presentations during the next PICES annual meeting and at other relevant venues
3. Contact information (continuous effort)
   • Compile list of experts on deep sea life history
   • Compile list of experts on deep sea circulation
   • Compile list of experts on deep sea connectivity
4. PICES in-person workshop (during PICES annual meeting)
   • Summarize subgroup work progress
   • Next steps

Year 2 (2027)

1. WG hybrid meeting (mid 2027)
   • Discuss schedules and plans of symposium sessions and presentations during the next PICES annual meeting and at other relevant venues
2. Study and preparation of reports (continuous effort)
   • Subgroup Biological (life history review, table of connectivity-relevant parameters)
   • Subgroup Physical (models/data review and recommendation)
   • Subgroup Connectivity (work plan for connectivity modeling and sensitivity analyses)
3. PICES in-person workshop (during PICES annual meeting in Japan)
   • Summarize subgroup work progress
   • Presentation of subgroup reports
   • Next steps

Year 3 (2028)

1. WG hybrid meeting (mid 2028)
   • Discuss progress of modeling and sensitivity
2. Conduct connectivity modelling and sensitivity analyses (continuous effort)
3. PICES in-person workshop (during PICES annual meeting in Japan)
   • Summarize progress
   • Presentation of connectivity and sensitivity analyses
   • Wrap up

This Working Group is committed to adhering to the PICES Data Management Policy and ensuring the responsible collection, sharing, and dissemination of data, in alignment with the FAIR principles (Findable, Accessible, Interoperable, and Reusable).

Data Accessibility and Sharing
All best practices developed by this working group will be openly published in peer-reviewed journals and made publicly accessible to the scientific community. The coding libraries compiled during the working group's activities will be hosted on GitHub, ensuring open access, transparency, and reproducibility. These libraries will include annotated datasets with appropriate metadata following PICES data-sharing guidelines to facilitate interoperability and broad usage.

Compliance with PICES Data Policy
The working group will ensure that all collected and processed data adhere to the PICES data policy by:

• Utilizing recognized open-access repositories and platforms for data storage and dissemination.
• Providing comprehensive metadata and documentation for reproducibility.
• Complying with data licensing and citation best practices.
• Ensuring that the datasets meet FAIR data principles.

Data Repositories
The working group encourages the use of well-established repositories for datasets, including:

• GitHub for dataset hosting and model sharing.
• Public repositories such as IEEE in compliance with international data-sharing policies.

Through these efforts, the working group aims to enhance data transparency, support international research collaboration, and facilitate the wider implementation of deep sea connectivity modelling.