Trevor Willis - Personal web page

BIOMARE is an AGIP funded research programme to examine multivariate variability in macrobenthic community structure in relation to the presence of gas platforms in the Adriatic Sea. The project has several aims: 1) characterisation of variability of soft sediment macrobenthic assemblages at multiple spatial scales, 2) differentiate random variability from that imposed by large-scale environmental gradients, 3) model relationships between gas platforms and benthos.

We collaborate and drink some rather good red wine with Drs Marti Anderson (University of Auckland) and Karl Ugland (University of Oslo).

Large monitoring datasets are available by virtue extensive benthos monitoring programmes run by various consulting companies in Norwegian oilfields. When new oil or gas wells are drilled, the lubricant used is of three types: oil-based, synthetic, or water-based (in order of perceived severity of impact on the environment). The type of drilling lubricant used has a large bearing on the toxicity of drill cuttings that were formerly dumped on the seabed (cuttings from newer wells are usually disposed of on land). These piles of cuttings take some time to erode (if they ever do) and continue to leach heavy metals for years. With Anders Bjørgesæter and Prof John Gray (University of Oslo, Norway), I aim to build a predictive model of recovery of macrobenthos following drilling activities, that is based on measured changes in the structure of macrobenthic assemblages over time. If and when we manage this, it can be applied to our data from the BIOMARE project in the Adriatic Sea to determine if general predictions can be made for different ecosystems.

My first love and continuing interest. My initial focus on reef fishes, while still important, has been extended to a more general interest in ecosystem effects. I have recently become interested in the idea that reserves could improve fishery assessment models by providing controls for experiments, and allow empirical estimation of parameters used in fishery models. Fellow conspirators include Drs Russ Babcock (CSIRO, Australia), Fabio Badalamenti (CNR, Italy), Marco Milazzo (University of Palermo, Italy), Nick Polunin (University of Newcastle, UK), Russell Millar, Marti Anderson, Nick Shears & Chris Denny (University of Auckland, New Zealand) and Nick Tolimieri (NMFS, USA). Much of my New Zealand work is published, except for analyses of some long-term fish monitoring data (with Marti Anderson), which we hope to get to this year... sometime.

Laurea student Giovanni Garaffa recently completed his laurea degree, in which he found that physical disturbance by a single storm event affected the dynamics of mussel (Mytilus galloprovincialis) beds (on artificial coastal protection barriers along the Adriatic coast) more than any other source of disturbance. Disturbances in mussel populations are known to be brought about by human harvesting and are likely to be affected by predation, but the contribution of the first storm at the end of summer to the structuring of the populations was unexpectedly high: around 30% of the total biomass was removed.

I maintain an interest in variability in reef fish assemblages, and in particular, the methods we use to assess them. By far the most flexible and commonly used approach - visual census by scuba divers - has many known and unknown biases, depending on the group of fish species under study. I continue to be involved in studies (presently with Dr Marco Milazzo of the University of Palermo) assessing these biases and the development of alternative methods, where appropriate.

PhD student Selvaggia Santin is investigating the dynamics of blennioid fish assemblages on coastal protection barriers and their interactions with structural and biological features of habitat.

Academic qualifications	2001	PhD, University of Auckland, New Zealand
	1994	MSc, Victoria University of Wellington, New Zealand
	1990	BSc, Victoria University of Wellington, New Zealand

Employment	2003-	Research fellow, University of Bologna
Employment	2001-2002	Postdoctoral fellow, University of Auckland

Other qualifications	2002	SSI Diver Stress & Rescue (SSI #6082180)
	1998	Occupational Divers Certificate of Competence - Research Diver (Occupational Safety & Health, New Zealand Department of Labour)
	1994	Restricted Radio Operators Certificate (No. AK25088, New Zealand Ministry of Commerce), and New Zealand Coastguard Day Skipper Certificate
	1989	NAUI Openwater Scuba Diver (AUQ44799)

Affiliations	Associate Editor Environmental Conservation New Zealand Ecological Society New Zealand Marine Sciences Society Fisheries Society of the British Isles

Links to colleagues	Professor Marco Abbiati Dr Laura Airoldi Dr Marti Anderson Dr Russ Babcock Dr Fabio Badalamenti Professor John Gray Dr Carlotta Mazzoldi Dr Marco Milazzo Associate Professor Russell Millar Professor Nick Polunin Dr Karl Ugland Ms Natalie Usmar

Publications	Santin S & TJ Willis (2007) Direct versus indirect effects of wave exposure as a structuring force on temperate cryptobenthic fish assemblages. Marine Biology (in press). Santin S, TJ Willis & M Abbiati (2006) Cryptobenthic fish and the importance of habitat on defense structures in the Adriatic Sea. Proceedings of the 15th Meeting of the Italian Society of Ecology (SItE) (in press). link to pdf Milazzo M, I Anastasi & TJ Willis (2006) Recreational fish feeding affects coastal fish behaviour and increases frequency of predation on damselfish (Chromis chromis) nests. Marine Ecology Progress Series 310: 165-172. Willis TJ, F Badalamenti & M Milazzo (2006) Diel variability in counts of reef fishes and its implications for monitoring. Journal of Experimental Marine Biology and Ecology 331: 108-120. pdf preprint Willis TJ (2005) Book review: Lequesne C "The politics of fisheries in the European Union". Environmental Conservation 32: 372. Willis TJ & RB Millar (2005) Using marine reserves to estimate fishing mortality. Ecology Letters 8: 47-52. pdf reprint Sharp NJ, BK Diggles, CW Poortenaar & TJ Willis (2004) Efficacy of Aqui-S, formalin and praziquantel against the monogeneans Benedenia seriolae and Zeuxapta seriolae infecting yellowtail kingfish (Seriola lalandi) in New Zealand. Aquaculture 236: 67-83. Denny CM, TJ Willis & RC Babcock (2004) Rapid recolonisation of snapper (Pagrus auratus: Sparidae) within an offshore island marine reserve after implementation of no-take status. Marine Ecology Progress Series 272: 183-190. Willis TJ (2003) Book review: Hart PJB & Reynolds JD (eds) Handbook of fish and fisheries, Vol I and II. Environmental Conservation 30: 410-411. Parsons DM, RC Babcock, RKS Hankin, TJ Willis, JP Aitken, RK O'Dor & GD Jackson (2003) Snapper (Pagrus auratus: Sparidae) home range dynamics: acoustic tagging studies in a marine reserve. Marine Ecology Progress Series 262: 253-265. Willis TJ & MJ Anderson (2003) Structure of cryptic reef fish assemblages: relationships with habitat characteristics and predator density. Marine Ecology Progress Series 257: 209-221. Willis TJ, RB Millar, RC Babcock & N Tolimieri (2003) Burdens of evidence and the benefits of marine reserves: putting Descartes before des horse? Environmental Conservation 30: 97-103. pdf reprint Sharp NJ, CW Poortenaar, BK Diggles & TJ Willis (2003) Metazoan parasites of yellowtail kingfish, Seriola lalandi, in New Zealand. Prevalence, intensity and site preference. New Zealand Journal of Marine and Freshwater Research 37: 273-282. Willis TJ, RB Millar & RC Babcock (2003) Protection of exploited fishes in temperate regions: high density and biomass of snapper Pagrus auratus (Sparidae) in northern New Zealand marine reserves. Journal of Applied Ecology 40: 214-227. pdf reprint Anderson MJ & TJ Willis (2003) Canonical analysis of principle coordinates: a useful method of constrained ordination for ecology. Ecology 84: 511-525. Willis TJ (2001) Visual census methods underestimate density and diversity of cryptic reef fishes. Journal of Fish Biology 59: 1408-1411. pdf reprint Willis TJ, DM Parsons & RC Babcock (2001) Evidence for long-term site fidelity of snapper (Pagrus auratus) within a marine reserve. New Zealand Journal of Marine and Freshwater Research 35: 581-590. pdf reprint Willis TJ & RB Millar (2001) Modified hooks reduce incidental mortality of snapper (Pagrus auratus: Sparidae) in the New Zealand commercial longline fishery. ICES Journal of Marine Science 58: 830-841. pdf reprint Willis TJ & RC Babcock (2000) A baited underwater video system for the determination of relative density of carnivorous reef fish. Marine and Freshwater Research 51: 755-763. Willis TJ, RB Millar & RC Babcock (2000) Detection of spatial variability in relative density of fishes: comparison of visual census, angling, and baited underwater video. Marine Ecology Progress Series 198: 249-260. Babcock RC, S Kelly, NT Shears, JW Walker & TJ Willis (1999) Changes in community structure in temperate marine reserves. Marine Ecology Progress Series 189: 125-134. Millar RB & TJ Willis (1999) Estimating the relative density of snapper in and around a marine reserve using a log-linear mixed effects model. Australian and New Zealand Journal of Statistics 41: 383-394. pdf reprint Willis TJ, JEH Saunders, DL Blackwood & JE Archer (1999) First New Zealand record of the Australian bridled goby, Arenigobius bifrenatus (Pisces: Gobiidae). New Zealand Journal of Marine and Freshwater Research 33: 189-192. Taylor RB & TJ Willis (1998) Relationships amongst length, weight and growth of northeastern New Zealand reef fish. Marine and Freshwater Research 49: 255-260. Willis TJ & RC Babcock (1998) Retention and in situ detectability of visible implant fluorescent elastomer (VIFE) tags in Pagrus auratus (Sparidae). New Zealand Journal of Marine and Freshwater Research 32: 247-254. Willis TJ & CD Roberts (1996) Recolonisation and recruitment of fishes to intertidal rockpools at Wellington, New Zealand. Environmental Biology of Fishes 47: 329-343. Haddon M, TJ Willis, RG Wear & VC Anderlini (1996) Biomass and distribution of five species of surf clam off an exposed west coast North Island beach, New Zealand. Journal of Shellfish Research 15: 331-339. Willis TJ (1995) A preliminary description of the fish fauna of Taranga (Hen) Island, north-eastern New Zealand. Tane 35: 57-68. Haddon M & TJ Willis (1995) A morphometric and meristic comparison of orange roughy (Hoplostethus atlanticus) from the Lord Howe Rise and Puysegur Bank, New Zealand, and its implications for stock structure. Marine Biology 123: 19-27.