SANTA CRUZ: CENTER FOR STOCK ASSESSMENT RESEARCH, DEPARTMENT OF APPLIED MATHEMATICS AND STATISTICS, JACK BASKIN SCHOOL OF ENGINEERING
20 December 2006
Memorandum to the Record
Report of Sabbatical Activities of Marc Mangel, Fall 2006
I was Frohlich Fellow at CSIRO Marine and Atmospheric Research, Hobart, Tasmania for the period 28 September to 3 November. When arranging this visit, we agreed that CSIRO would fund travel and rental assistance only and that I would cover the cost of rental car and subsistence from my research grants that support work relevant to Antarctic krill and disease.
Activities at CSIRO
My main research activities at CSIRO were a collaboration with Natalie Dowling and Chris Wilcox on models of fleet dynamics in the eastern tuna/billfish fishery and with Chris Wilcox on optimal control of invasive species. Both of these projects involve novel and important applications of the method of stochastic dynamic programming; I can state without hesitation that had I not come for this month, the work could not have been done.
Dowling, Wilcox and I have formulated and developed the first version of code to allow one to predict how long-line vessels will respond to spatial management of effort (through decrements in hook allocations that vary according to fishing location). We are thus able to predict the spatial distribution of fishing effort, the landed catch as a function of week, and the price of the target species. I believe that this work has great potential for expansion, and would be easily modified to model quota rather than effort based fisheries. We are currently working on a paper for the Canadian Journal of Fisheries and Aquatic Sciences.
Wilcox and I have formulated and developed the first version of code for a decision framework that allows one to conclude that the population of an invasive species is sufficiently low that it will decline rather than grow. The major problem here is that one never knows the actual size of the population and must make decisions based on imperfect observations. Our framework allows one to either conclude the extirpation activity has been successful, continue to monitor, or to take action by reducing the number of invasive species. We are currently working on a paper for Science.
During the first week of my visit, my post-doc Kate Creswell joined me from Santa Cruz and she gave a seminar on our work concerning the foraging behavior of penguins in relation to krill variability. During the last week of my visit, I gave a talk on work with PhD student Nick Wolf concerning the decline of Steller sea lions in the Gulf of Alaska. I also made time to meet with various students and colleagues at CSIRO. I had a number of meetings with James Dell, PhD student of Chris Wilcox, to discuss aspects of his work on modeling the behavior of fishermen (particularly how one can construct prior distributions for fishing locations, given environmental information). I also had meetings with Marinelle Basson and Mark Bravington (both long-time colleagues), Jemery Day (whom I met when I lectured at a summer school in Vancouver in 1993), Rich Little, Tim, Reid, Jonathan Rhodes, Tony Smith, Geoff Tuck, and Jay Willis (to whom I had previously given advice on a paper concerning krill life histories).
Activites at CSIRO/UTAS
One of my great pleasures in being at CSIRO was to be able to meet and interact with Graeme Dunston (CSIRO), June Olley and David Ratkwosky (both UTAS). They have done seminal work on how bacterial growth responds to variation in temperature, and what the mechanism for the response is. Through my in-person (vs email) conversations with them, I was able to gain key insights for my own work on an evolutionary theory of fever and this would not have happened had I not been at CSIRO. This work is supported by my own NSF grant, and when I ultimately write it up I shall thank both NSF and CSIRO for the Frohlich fellowship.
Activities at AAD/UTAS/CCAMLR
I also have a major research grant, funded by the Lenfest Ocean Program in the US, for work on the response of krill and krill predators to climate change and the implications for fishery management. Consequently, I took the opportunity of being in Hobart again to strengthen my links with AAD. Early in my visit, I had an afternoon session with group leaders in Kingston (Steve Nicol, Nick Gales, Colin Southwell and Andrew Constable). I subsequently met with Gales and his group of scientists working on predators, with Nicol and So Kawaguchi to discuss krill, and with Andrew Constable to discuss ecosystem based approaches to management. I met many young scientists at AAD and had especially good talks with Toby Jarvis and Natalie Walker on interpretation and application of acoustic data. In conjunction with my work on krill, I met with Manuel Nunez (UTAS) to discuss ways to predict UV intensity at the surface of the ocean, given a particular location.
The Scientific Committee (SC) of the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) met the last two weeks of October. Although I am not serving on the US delegation this year, I took the opportunity of the meeting of SC-CCAMLR to interact with colleagues from around the world. In addition, at the request of the Pew Foundation, Steve Nicol (Australia), Keith Reid (UK) and I started planning a small workshop on indentifying and resolving uncertainties in krill fisheries models, to be held in Santa Cruz in May 2007.
Mote Symposium
The Sixth Mote Symposium on Fisheries Ecology was held in Sarasota, Fl during the week of 12 November 2006. I served on the organizing committee of this symposium and presented an invited talk on combining proximate and ultimate approaches to life history variation in salmonids. University of Bergen
I visited the modeling group in the Department of Biology at the University Bergen, 3-13 December 2006. During this period, I interacted with all of the students, faculty and post-docs (about 15 people) in the group. In addition, two of my doctoral students defended their degrees on 7 and 8 December. Three of the four opponents were able to give invited talks, so it was a wonderful week of science.
Summary
This sabbatical allowed me to expand my research in new directions, learn some new things (especially about fever and UV damage) and move my existing projects forward. I expect to write 4 papers on the basis of work done during this sabbatical: one on behavioral models for the Eastern Australian Current tuna fleet, one on optimal control of an invasive species with an Allee effect, one on the evolutionary theory of fever, and one on fetal syndrome and hormesis as two sides of the same life history coin. In addition, my krill work was substantially moved forward, and I will get to advance that in Winter, 2007.
Marc Mangel Professor SANTA CRUZ: DEPARTMENT OF APPLIED MATHEMATICS AND STATISTICS, JACK BASKIN SCHOOL OF ENGINEERING
25 June 2007
To: The Record From: Marc Mangel
Report of Sabbatical Activities of Marc Mangel, Spring 2007
During this term, I spent approximately two months at the University of Oxford (two weeks as Astor Lecturer and six weeks to collaborate with colleagues on disease and krill ), ran an international workshop at the request of the Lenfest Ocean Program, spent a week in La Paz, BCS on research related to my UCMEXUS grant, and gave the Olin College of Engineering and Mathematics Keynote Address at the World Conference on Resource Management.
Visit to Oxford (15 March -10 May)
The Astor Lecture and Other Seminars
I gave the Astor Lecture “Ecology, Conservation and Public Policy: A Vision for the 21st Century” at the Department of Zoology on 30 April 2007. About 100 people attended, including many from Zoology and Oxford University Centre for the Environment and Sir David Cox from Statistics/Nuffield College.
In addition, I gave the following seminars:
• “The Decline of Steller Sea Lions in the Western Gulf of Alaska” at Imperial College/Marine Resources Assessment Group (21 March 07) and at the Oxford University Centre for the Environment (9 May 07)
•”Evolutionary Analysis of Longevity and Diversity, motivated by the Pacific Rockfish” at the University of Leicester (17 April 07) and Imperial College at Silwood Park (23 April)
•”The Ten Plagues and Statistical Science as a Way of Knowing” at the George Slager Centre, University of Oxford (25 April 07)
I was also a Guest Speaker and Tutor at “Populations Under Pressure: A Graduate Research Symposium” at Imperial College at Silwood Park (29 March 07)
1 Research Interactions
While in Oxford, I embarked on a new line of research with my collaborator Dr. Michael Bonsall (Department of Zoology) – the evolutionary ecology of stem cells and their niches.
Fuchs et al (Cell 116:769-778, 2004), in a wonderful article on stem cells and their niches, note that the potential of stem cells in regenerative medicine relies on the assumption that we can remove them from their natural habitat, propagate them in culture, transplant them into a foreign environment and assume that the transplanted cells will do as we wish. However, Anderson (Neuron 30:19-35, 2001) pointed out that there may be enormous differences between what stem cells do in the original niche and what they can do when put into culture or when transplanted to a new location. In 2003, Raff (Annual Review of Cell and Developmental Biology 19:1) noted that “perhaps the greatest challenge in stem cell biology is to uncover the..mechanisms that determine whether a daughter of a stem cell division self-renews or commits to a particular pathway of differentiation. Cracking this problem for the adult mammalian stem cells of interest will be a crucial step for both developmental biology and cell therapy” (pg 16). Indeed, in many ways we have made great progress, but in others very little in understanding the probability of renewal, especially the great variability that genetically identical stem cells from adjacent niches show. The classic experiments of Till et al. (e.g. PNAS 51:29-36, 1964) documented this variability, but much of it remains unexplained – particularly the quiescence of stem cells within their niches.
Although it is probably now treated as an old saw, the observation of Theodosius Dobzhansky that “nothing in biology makes sense except in the light of evolution” (and the converse by Gerhardt and Kirschner that “nothing in evolution makes sense except in the light of cell biology”) is as true today as when he said it nearly 35 years ago. Weissman and colleagues have made very convincing arguments that stem cells are fundamental units on which natural selection acts. Thus, it is essential that we keep evolutionary considerations in mind as we move towards stem cell therapies. The record of the last 60 years regarding the development of resistance to insecticides, herbicides and antibiotics should be sufficient to convince anyone that these are not academic issues, but ones of fundamental importance for application.
A wide variety of questions concerning the evolutionary biology of stem cells are directly applicable to regenerative medicine. These include what sets the number of stem cells in certain tissues (e.g. the villi, which are very well studied), why has natural selection lead to different levels of potency of stem cells in different tissues, how has natural selection acted on the probability of renewal by a stem cell, why do some tissues show growth compensation whereas others do not, and how will the hematopoietic system respond to challenges of different sorts? Answering these questions will help guide our work in regenerative medicine. To answer them glibly as relics of evolutionary history is as
2 intellectually sound as saying that this is the way the intelligent designer designed them.
We have already done a variety of statistical and mathematical analyses, have had accepted a short paper for the journal Oikos and are in the process of preparing a larger paper.
Research Interactions – Southern Ocean Krill
I continued my work on krill life histories with colleagues Steve Nicol (Australian Antarctic Division who was visiting the UK), Keith Reid (British Antarctic Survey), Alex Kacelnick (Oxford) and John McNamara (Bristol). This work consisted of further elaborations of the work on krill and UV that I started in the fall, and on the indirect effects of krill fisheries on krill predators.
Research Interactions – Other Students, Post-docs and Faculty
In Oxford, I had a variety of meetings to discuss research questions of colleagues. I met with the following students and post-docs (Zoology at Oxford unless otherwise noted):
Nina Alphey Nim Ariminapathy Tom Bell Tiffany Bogich (Zoology, University of Cambridge) Nils Bunnefeld (Centre for Population Biology, Imperial College at Silwood Park) Annie Carmichael (Geography, Oxford) Becky Dean Robert Gramacy (Centre for Statistical Ecology, University of Cambridge) Colin Harrower Tom Hart (Centre for Population Biology Imperial College at Silwood Park) Lizzy Jeffers (Geography, Oxford) Leah Johnson (Centre for Statistical Ecology, University of Cambridge) Kirsty McGregor (Centre for Population Biology, Imperial College at Silwood Park) Chloe Strevens Jo Wimpenny Alex Wilson (Centre for Population Biology, Imperial College at Silwood Park) Laith Yakob
I met with the following faculty colleagues to discuss research questions of mutual interest:
Prof John Beddington FRS (Imperial College) Prof David Clary FRS (Chemistry, President Magdalen) Dr. T. Coulson (Imperial College at Silwood Park) Prof Sir David Cox FRS (Statistics) Prof Sir Richard Gardner FRS
3 Prof Charles Godfray FRS Dr. Chris Graham Dr. Ivana Gudelj (University of Bath) Prof Lord Krebs FRS Dr. R Ladle (Geography, Oxford) Dr. K. Lorenzen (Imperial College at Silwood Park) Prof Angela MacClean Dr. EJ Milner-Gulland (Imperial College at Silwood Park) Prof Lord May FRS Prof Randolph Nesse (University of Michigan, meeting in London) Dr. Keith Reid (British Antarctic Survey) Prof Bernard Silverman FRS (Master, St. Peters) Prof Jeremy Thomas Prof R Whittaker (Geography, Oxford)
Colleagues Christian Jørgensen (University of Bergen) and Bruno Ernade (IFREMER, the French Research Institute for Sustainable Exploitation of the Sea) visited Dr. Bonsall and me on 19 and 20 April, for the four of us to work on connecting life history optimization models and evolutionary trajectories.
I also spent time in Oxford discussing the potential school of public health at UCSC with colleagues there, especially Lord Krebs and Prof MacClean.
Lenfest Ocean Program Workshop “Identifying and Resolving Uncertainties in Management Models for Krill Fisheries” (21-25 May 2007)
The Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) is moving towards managing krill harvests on a small scale (Small Scale Management Units). At the request of the Lenfest Ocean Program, I organized a workshop to provide CCAMLR with independent advice on how Small-Scale Management Units (SSMUs) might be used to minimize local impacts of krill fishing on krill predators, including consideration of what science might be needed to improve their use for management purposes.
The workshop was intended to highlight what information is critical to know about krill, krill-predator interactions, and current models in order to make SSMU management decisions, to clarify which information has relatively low uncertainty and to identify information that is missing or has great uncertainty and what is needed to gather the information or reduce the uncertainty. Underlying all of these questions is the rate of human-induced climate change in the Southern Ocean, forcing organisms (both krill and their predators) to experience environments that may be beyond their evolutionary history.
The participants at this workshop were scientists who work on krill within the CCAMLR community (but representing themselves as individuals, rather than any national
4 delegation) and who work on krill or other related ecological questions outside of the CCAMLR community. Three major themes ran through our discussions:
•What are the key aspects of biology of krill and their predators that must be included in effective management models?
•How should such models be benchmarked and declared ready to use?
•What further research, if any, needs to be undertaken in response to the previous two questions?
I authored a summary letter, sent to the Chair of the Scientific Committee of CCAMLR.
La Paz, BCS (27 May-3 June 2007)
In La Paz, Dr. Tania Zenteno-Savin and I continued our UCMEXUS supported collaboration on oxidative damage and diving in marine mammals. The group of Zenteno-Savin is analyzing tissue samples from several species of marine and terrestrial mammals for antioxidant enzyme activities and oxidative damage. Our objective is to use the data on oxidative stress, as well as the information in the literature on dive depth and duration, to create a mathematical model predicts the level of reactive oxygen species, antioxidant defences, and associated damage due to reperfusion of cells following a dive. Our long term goal is a model that can be used in medicine to predict the outcome in patients suffering ischemia-related diseases.
World Conference on Natural Resource Modeling (19-22 June 2007)
The 2007 World Conference on Natural Resource Modeling was held June 19 - 22, 2007 on Cape Cod, MA. This conference showcased natural resource issues (predominately in fisheries and forestry) and with an emphasis on the use of science to support the development of public policy and effective management. I gave The Franklin W. Olin College of Engineering Address “Natural Resource Modeling in the 21st Century: The Certainty of Uncertainty”.
I explained the characteristics of environmental problems that make them wickedly hard to solve. Among other aspects, wicked problems are swathed in uncertainty and in the 21st century resource modelers must confront this uncertainty. I used a retro-classic – competition between flour beetles – to illustrate how multiple models may be brought to the same empirical situation. Coming back to the present, I explained how Bayesian non- parametric approaches (a field in which AMS at UCSC leads the world) will allow us to stop arguing about the ‘correct’ form of a stock-recruitment relationship and instead let the data guide us. I closed with some recommendations for how our work should proceed in the future.
Among other things, I made contacts with the Olin College of Engineering which I
5 believe will pay off for UCSC in attracting top flight grad students in the future.
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