Professor Kendall David Clements
Research | Current
My research interests centre on the nutritional ecology and evolution of fishes. Most of my research has focused on the biology of marine herbivorous fishes, which I study in both temperate and tropical reef environments. My early work on marine herbivorous fishes involved feeding morphology and diet, and I subsequently became interested in how these fishes digested their algal (seaweed) diet. It became clear that, as in most terrestrial vertebrate herbivores, symbiotic microorganisms inhabiting the posterior intestine played an important role in digestion. Determining how these organisms contribute to the nutrition of host fishes became an important component of my research, and that continues to this day. This involves a large variety of research techniques including diet analysis, nutrient analysis, stable isotope analysis, electron microscopy, histology, growth studies, molecular characterization of gut microbial communities, digestive enzyme studies and short chain fatty acid analysis.
PhD students Selena McMillan and Kate Johnson preparing pellet samples of hindgut microflora from herbivorous fishes on board University of Auckland research vessel Hawere at Great Barrier Island, December 2010.
Processing gut samples from herbivorous fishes immediately post-capture at Lizard Island, Great Barrier Reef, with PhD student Kate Johnson and Prof. Howard Choat (James Cook University) in May 2013.
As we began to understand how feeding and digestion varied among different groups of herbivorous fishes we sought an evolutionary framework for the work. This involved generating molecular phylogenies of various fish groups, including odacines (butterfishes or weed whitings), acanthurids (surgeonfishes), scarines (parrotfishes), nibblers (girellids) and drummers or sea chubs (kyphosids). Part of this work involves resolving taxonomic problems in these groups, and this has led to the discovery of unrecognised species. My taxonomic expertise on fishes led to me participating in IUCN workshops on surgeonfishes, parrotfishes, rabbitfishes and triplefins, and contributing to five chapters of the TE Papa NZ EEZ Fishes book (triplefins, butterfishes, lanternfishes, drummers and nibblers).
Photo of a new species of parrotfish identified from Western Australia. This photo was taken at the Houtman Abrolhos Islands in 2010.
Photo of the newly described drummer species from Western Australia, Kyphosus gladius (top), above its sister species, K. sydneyanus. The photo was taken at Rottnest Island, where the two species co-occur. See Knudsen and Clements (2013) Zootaxa 3599: 001-018.
Most recently we have been expanding our evolutionary work to look at the timing and biogeography of diversification in these fish groups, i.e. where did they originate, how old are they, and how rapidly did they diversify? This led to an interest in mechanisms of speciation, a subject that I have also examined in the highly diverse endemic triplefin fauna of New Zealand. This group of 27 fish species has radiated to occupy many habitats in New Zealand waters, including estuaries, rock pools, reefs and the continental shelf down to 500 metres. As a result of this work I developed an interest in ecological speciation, i.e. speciation driven by natural selection on ecological characters. I currently supervise six PhD students working on topics including evolution and taxonomy of drummers (Kyphosidae), diet and nutrition in parore (Girella tricuspidata), nitrogen metabolism in hindgut symbionts of marine herbivorous fishes, gut anatomy and protein uptake in marine herbivorous fishes, and the effects of habitat on growth and fecundity in triplefin fishes. I have students based on both the city campus and at the Leigh Marine Laboratory, and much of our sampling involves fieldwork at offshore islands using the University's research vessel Hawere. We also have field programs in tropical locations, especially Lizard island on the Great Barrier Reef.
PhD student Steen Knudsen examining kyphosid specimens on a charter vessel at the Houtman Abrolhos Islands, Western Australia, in May 2010.
Dinner on board R.V. Hawere anchored at Great Barrier Island, June 2013. Left to right: visiting Brazilian PhD student Thiago Costa Mendes, PhD student Paul Caiger, KDC, Massey collaborator (and former PhD student!) Elizabeth Laman Trip, and skipper Brady Doak.
Working on gut microflora from tropical marine herbivorous fishes at the Lizard Island Research Station, May 2013. Left to right: AUT Marsden collaborator Associate Professor Lindsey White, Cornell University Marsden collaborator Prof. Esther Angert, and PhD student Kate Johnson.
Areas of expertise
Ecology, Evolution and Behaviour
Selected publications and creative works (Research Outputs)
- Arroyo, F. A., Pawlowska, T. E., Choat, J. H., Clements, K. D., & Angert, E. R. (2019). Recombination contributes to population diversification in the polyploid intestinal symbiont Epulopiscium sp. type B. ISME Journal10.1038/s41396-018-0339-y
- Mendes, T. C., Ferreira, C. E. L., & Clements, K. D. (2019). Discordance between diet analysis and dietary macronutrient content in four nominally herbivorous fishes from the Southwestern Atlantic (vol 165, 180, 2018). MARINE BIOLOGY, 166 (1)10.1007/s00227-018-3448-2
- Mendes, T. C., Ferreira, C. E. L., & Clements, K. D. (2018). Discordance between diet analysis and dietary macronutrient content in four nominally herbivorous fishes from the Southwestern Atlantic. MARINE BIOLOGY, 165 (11)10.1007/s00227-018-3438-4
- Visconti, V., Trip, E. D. L., Griffiths, M. H., & Clements, K. D. (2018). Life-history traits of the leatherjacket Meuschenia scaber, a long-lived monacanthid. Journal of fish biology, 92 (2), 470-486. 10.1111/jfb.13529
- Visconti, V., Trip, E. D. L., Griffiths, M. H., & Clements, K. D. (2018). Reproductive biology of the leatherjacket, Meuschenia scaber (Monacanthidae) (Forster 1801) in the Hauraki Gulf, New Zealand. New Zealand Journal of Marine and Freshwater Research, 52 (1), 82-99. 10.1080/00288330.2017.1331919
- Schiel, D. R., Ayling, T., Kingsford, M. J., Battershill, C. N., Choat, J. H., Andrew, N. L., ... Poynter, M. (2018). Change in the rocky reef fish fauna of the iconic Poor Knights Islands Marine Reserve in north-eastern New Zealand over 4 decades. Marine and Freshwater Research10.1071/MF18037
- Johnson, J. S., Clements, K. D., & Raubenheimer, D. (2017). The nutritional basis of seasonal selective feeding by a marine herbivorous fish. Marine Biology, 164 (10)10.1007/s00227-017-3223-9
- Clements, K. D., German, D. P., Piche, J., Tribollet, A., & Choat, J. H. (2017). Integrating ecological roles and trophic diversification on coral reefs: Multiple lines of evidence identify parrotfishes as microphages. Biological Journal of the Linnean Society, 120 (4), 729-751. 10.1111/bij.12914