Dian J. Gifford (1948–2024): Biological Oceanographer Who Documented Microzooplankton–Metazoan Trophic Linkages

Dian J. Gifford (1948–2024) passed away peacefully August 24, 2024 at her home in New Bedford, MA. She was a pioneer in the study of microzooplankton ecology, especially their importance in the diet of calanoid copepods, ctenophores, and other metazoan zooplankton and their overall role in energy flow through marine ecosystems (Fig. 1). Dian was born and raised in Beverly, Massachusetts, USA. She received her B.A. cum laude with Honors in Biology from the University of Massachusetts (1973) and her M.Sc. (Biology, 1979; Adviser Patricia Lane) and Ph.D. (Oceanography, 1986; Adviser Carl Boyd) from Dalhousie University in Halifax, Nova Scotia, Canada. She maintained close connections to many friends and colleagues from Dalhousie. She was a Postdoctoral Research Scientist at Louisiana Universities Marine Consortium with Michael Dagg (1986–1988) and then moved to the Graduate School of Oceanography (GSO), University of Rhode Island in 1989 where she remained until 2006, eventually as a Senior Marine Research Scientist and Adjunct Professor of Oceanography (continuing as Emerita post-retirement). She supported herself on soft money (NSF, ONR) for her entire career. In several widely cited chapters and papers produced throughout her career, she (with collaborators), described in detail methods and constraints for sampling, preserving, culturing, and conducting feeding experiments with marine protozooplankton (Stoecker et al. 1994; Båmstedt et al. 2000; Gifford and Caron 2000). Dian's paper on culturing marine oligotrichous ciliates clearly described the problems in manipulating and handling these organisms experimentally as well as how to approach culturing them (Gifford 1985). These methodology papers were important contributions to aquatic microbial ecology and zooplankton ecology. They influenced and facilitated subsequent lab and field studies of microzooplankton, were valuable written resources for students and established scientists, and contributed to the recognition and inclusion of microzooplankton in plankton ecosystem projects. Dian's field studies of copepod feeding on natural assemblages showed that in nature protistan microzooplankton were important parts of the diet of dominant estuarine (Gifford and Dagg 1988; Gifford 1991) and open-ocean copepods (Gifford 1993). Documenting that larval ctenophores in natural assemblages also depended on microzooplankton prey to grow was important in showing how integral microzooplankton are in marine food webs of all sorts (Sullivan and Gifford 2004). Dian's work extended beyond larval ctenophores to contribute to understanding population level effects of climate change on this key predator in the Narragansett Bay ecosystem (Costello et al. 2006a; Sullivan et al. 2008) and how Mnemiopsis leidyi repopulates coastal ecosystems by finding refugia in winter (Costello et al. 2006b). Dian was instrumental in several of the major large-scale oceanographic projects of the last few decades, including SUPER (Subarctic Pacific Ecosystem Research), North Atlantic Bloom Experiment (Gifford et al. 1995), Thin Layers (coastal Washington) (McManus et al. 2003), and Georges Bank GLOBEC (Global Ocean Ecosytems Dynamics Northwest Atlantic). For GLOBEC, she was Chief Scientist on 4 research cruises to Georges Bank, served on the GLOBEC Executive Committee for Phases 3 and 4 and was a member of the GLOBEC International Working Group on Process Studies. Besides her own cruise research (Sieracki et al. 1998; Wishner et al. 2003), she worked with John Steele and others on a series of GLOBEC synthesis papers dealing with end-to-end models and fisheries impacts (Steele et al. 2007; Collie et al. 2009; Gifford et al. 2009; Ruzicka et al. 2016). Dian was also a valued member of the community. She supervised several M.S. and Ph.D. students (Peter Garrahan, Elena Martin, Lindsay Sullivan) and postdocs (Jeffrey Van Keuren, Rebecca Waggett), took students and other professionals to sea, mentored undergraduates, and worked with many colleagues at GSO and elsewhere. She was generous lending equipment and providing advice. She was a superb writer who could effectively organize key thoughts and arguments in proposals and publications. She was a member of various scientific organizations, including ASLO, and presented numerous talks at scientific meetings. She was a Science Advisor to URI's Metcalf Institute for science journalists, a consultant at several environmental businesses and nonprofit organizations, and grant coordinator at Curry College. An important contribution to GSO was her leadership in getting the University's Board of Governors to approve a formal Marine Research Scientist position allowing soft money scientists to submit independent proposals as lead PI and have independent office and lab space and a defined salary scale and career track. This has been a critical issue for diversity and scientific progress in the field of oceanography, since this field relies on so many soft money investigators. In addition to her research and contributions to the scientific community, Dian was an accomplished artist (painting and sculpture) and art lover. She had several dogs through the years that she was devoted to. She was a great conversationalist with strong opinions, had a wide range of friends and colleagues, and always knew the latest happenings in the broader scientific community. She appreciated good food and cultural events and enjoyed international travel adventures. She is survived by a stepdaughter and several cousins, nieces, and nephews. Her friends will miss her greatly.