Conveners and panellists of Session P: LaTreese Denson, Kenneth Rose, Rishi Sharma, Stephan B. Munch, Fabian Zimmermann und Claire Paris

Recruitment dynamics in a changing environment: what we know and how to deal with it (ICES ASC 2017)

At this year’s ICES Annual Science Conference in Fort Lauderdale, Florida, session P on recruitment dynamics, organized and co-convened by ConEvolHer, took place on the first two days of the conference. The session featured 20 presentations on a wide range of topics from fundamental biology of recruitment to spatial processes that are crucial for recruitment success and implementations of recruitment dynamics in stock assessment. The session concluded with a panel discussion of four distinguished experts, focussing on ways to move forward in understanding recruitment dynamics and implement them better in a management context.

The session was opened by a keynote lecture of Stephan B. Munch (NOAA/UCSC) who presented experimental evidence for transgenerational plasticity in fish and a novel method to predict recruitment through time-delay embedding that outperforms other classic approaches to recruitment prediction. The session continued with a range of talks that explored the underlying recruitment biology in various populations and ecosystems, including herring and sandeel in the North Sea, Baltic cod or Atka mackerel in the Bering Sea. A key topic were spatial dynamics relevant for recruitment, such as drift patterns and distribution of red snapper eggs and larvae in the Gulf of Mexico and South Atlantic or how heterogeneous spatial mortality affects recruitment of Northeast Arctic cod.

Stephan B. Munch giving the keynote lecture on recruitment and experimental evidence that transgenerational plasticity may contribute to observed dynamics.

On the second day, the focus shifted from a functional understanding of recruitment dynamics towards their relevance in stock assessment and management. The topics discussed by the presenters included questions such as how spatial aspects and connectivity can be included in stock assessment models, integrating environmental effects on recruitment in stock assessment predictions or what the risks and benefits are of doing so. Furthermore, more management-orientated issues were presented, including the role of recruitment dynamics in the management strategy of Patagonian grenadier or demersal fish communities in the Mediterranean Sea.

These questions were taken up in the following panel discussion of the panellists Claire Paris (RSMAS), Kenneth Rose (LSU), Rishi Sharma (IOTC) and Stephan B. Munch, who were discussing the progress that has been made in understanding and handling recruitment dynamics, the many challenges that remain and how the adequate management response also depends on the stock-specific properties, management targets and stakeholder interests. Overall, many important issues and perspectives were brought up and met with a large interest of the audience. The organizers and conveners of the session, ConEvolHer members Fabian Zimmermann and Katja Enberg as well as LaTreese Denson and Elizabeth Babcock from RSMAS Miami, look back on a successful session that put the topic of recruitment dynamics and their relevance for management back on the map of ICES.