Doctoral defence Ken Haste Andersen

Doctoral defence
Fish and Fisheries – the size- and trait-based approach

Professor Ken H. Andersen
Technical University of Denmark


Professor Marc Mangel, University of California, USA
Professor Terrance J. Quinn II, University of Alaska Fairbanks, USA

Both opponents are appointed by DTU and have been part of the assessment committee with the chairman also appointed by DTU, Professor Michael Pedersen, DTU Compute

Unofficial opponents are to address the moderator:

Provost Rasmus Larsen
Building 101A
Technical University of Denmark
Tel.: 45 25 71 42

A copy of the dissertation can be obtained by contacting:

Anna-Maria Lund
Office of Research and Relations
Building 101A
Technical University of Denmark
Tel.: 45 25 71 42


Fish and Fisheries
The size- and trait-based approach

This thesis develops a general theoretical framework to describe fish stocks and fish communities. The theory is applied to quantify the impact of fisheries on single fish stocks and on the entire fish community. The theory is rooted in the description of individual organisms, each described by a number of biological traits, the most important being the body size. From this basis follows a description of the size distribution of individuals in an entire marine ecosystem, from bacteria to whales (Chapter 2). The description of the ecosystem defines the growth and mortality of individual fish (Chapter 3), which leads to a derivation of the demography of a single stock (Chapter 4). These foundations are used to develop ecological and evolutionary impact assessments of fishing (Chapter 5). Well known concepts from classic theory, such as maximum sustainable yield, yield per recruit, cohort biomass, fisheries reference points, and the impact of size selective fisheries, are being re-developed, and deeper insights that have been hidden from classic theory are uncovered. The theory of the single stock is generalised to cover entire fish communities with many species (Chapter 6), and the impact of fishing on the entire community is developed (Chapter 7). Finally, the thesis discusses the evolutionary background for the life history strategy of fish and places the theory in relation to other modern population theory (Chapter 8). The mechanistic foundation of the theory, and the demonstrated capability to make ecosystem oriented impact assessments of fishing, makes the size-based theory a practically viable tool to support the development of ecosystem based fisheries management.


Mon 18 Sep 17
14:00 - 18:00




Danmarks Tekniske Universitet
Anker Engelunds Vej 1
Bygning 101A, 1.sal
Mødelokale 1