School of Natural and Environmental Sciences

Staff Profile

Dr Gary Caldwell

Senior Lecturer in Applied Marine Biology


Roles and Responsibilities

Marine Science Postgraduate Research Student Selector


  • B. Sc.(Hons 1st Class) Uni. Wales, Bangor
  • Ph. D. Newcastle University

Previous Positions

  • 2005-6. Marine Biology Teaching Fellow, Newcastle University
  • 2004. NSERC Postdoctoral Fellowship (University of Calgary and Environment Canada)
  • 2003-4. Research Associate, Newcastle University, Soil Association Scotland.



Research Interests

Google Scholar profile

My research interests and activities are broad in nature. The main research themes are described below.

Algae Biotechnology

I am active in developing algae (both micro- and macroalgae) as sources of marine biofuels and bioactive products, working on aspects of algae culture, anaerobic digestion (including the recently completed £2.8 million InnovateUK-BBSRC SeaGas project), low energy harvesting systems (notably foam flotation), functional biocomposites, and for a range of ecosystem services. I also apply algae biotechnology in rather more unconventional scenarios, for example as part of our built environment - see the Euro 3.4 million H2020 project, Living Architecture.

Chemical Ecology

I have long standing interests related to plant, animal and microbial interactions which are mainly modulated by chemically driven processes, e.g. production of toxic metabolites (e.g. polyunsaturated aldehydes) and/or the production of non-toxic but otherwise biologically active compounds. I am especially interested in the role of algal-derived compounds in structuring aquatic food webs. 

Ecotoxicology and Marine Venoms

I am interested in the biological response of organisms following exposure to xenobiotics and marine venoms, particularly where multiple stressors are involved. 

Marine Microbiomes

I am currently working on characterising the microbiomes associated with hadal trench amphipods, coastal sponges, sea cucumber, seaweeds and microalgae.

Current Postgraduate Supervision

  • Leah Brown (MPhil) - Gut microbiome of deep sea (hadal depth) amphipods. Co-supervised with Dr Alan Jamieson. [under examination]
  • Chloe Eastabrook (PhD) - Mixture toxicity: metals, non-ionising radiation and the cyanotoxin beta-methylamino-L-alanine. Co-supervised with Dr Knut Erik Tollefsen and  Prof. Tony Clare.
  • Prayoon Enmak (PhD) - Intensifying foam flotation for harvesting microalgae. Co-supervised with Prof. Adam Harvey and Dr Jon Lee.
  • Alex Goodridge (PhD) - Novel biocatalysts to improve the degradation of macroalgae biomass. Co-supervised with Dr John Bothwell
  • Rachel Hart (MPhil) - Developing microalgae biocomposites for wastewater bioremediation. Co-supervised with Dr Maxim Kapralov.
  • Iain Hope (PhD) - RuBisCo dynamics in cold adapted algae. Co-supervised with Dr Maxim KapralovDr Jon Telling and Dr Dana Ofiteru.
  • Warm In-Na (PhD) - Developing sustainable microalgae biocomposites for carbon capture applications. Co-supervised with Dr Jon Lee.
  • Alfonsina Milito (PhD, Open University) - Ovothiol, a marine antioxidant: discovery of its biological activities. Co-supervised with Dr Anna Polumbo and Christophe Brunet.
  • Salihu Musa (PhD) - Cost effective biodiesel production from microalgae by reactive extraction in a foam column. Co-supervised with Dr Jon Lee. [under examination] 
  • Belinda Njumo (PhD) - Developing algae biofuel technology for Cameroon. Co-supervised with Dr Ethan Hack and Dr Thomas Howard.
  • Matthew Pickersgill (PhD) - Microalgae and wastewater treatment: an industrial case study. Co-supervised with Dr Jon Lee.
  • Natalie Waite (MPhil) - Neutral modelling of complex microbial systems. Co-supervised with Dr Will Reid.  
  • Matthew Walker (MPhil) - Algae biocomposites for wastewater treatment. Co-supervised with Dr Maxim Kapralov and Dr Jon Lee.
  • Johanna Weston (PhD) - Biogeography of halal trench amphipods. Co-supervised with Dr Alan Jamieson.

Completed PhDs: Dr Rebecca Taylor [The role of diatom aldehydes in the benthos: grazing defence or diatom signal molecule?]; Dr Hannah Dunston [Impacts of algal biotoxins on the freshwater survival of Atlantic salmon]; Dr Helen Pagett [Characterising glycans involved in barnacle gregariousness]; Dr Susan Fitzer [Multigenerational effects of CO2-induced ocean acidification on the copepod Tisbe battagliai]; Dr Thea Coward [Foam fractionation: an effective technology for harvesting microalgae biomass]; Dr Hilary Redden [Seasonal aspects relating to the potential use of macroalgae as biofuel]; Dr Alessandra Gallina [The role of polyunsaturated aldehydes in the life and biology of the marine diatom Skeletonema marinoi in culture and in situ]; Dr Supanut Pairohakul [Evidence for polyunsaturated fatty acid biosynthesis in the ragworm (Nereis virens) and the lugworm (Arenicola marina)]; Dr Helen Graham [Determining the impacts of ocean acidification on reproductive and developmental fitness of marine invertebrates]; Dr Alanoud Rawdhan [Ultrastructural studies of micro-algae in infochemical manipulated mass culture]; Dr Guang Gao [Developing systems for the commercial culture of Ulva species in the UK]; Dr Norlaila Mohd Zanuri [The effects of environmental contaminants and ocean acidification on reproductive success in marine invertebrates]; Dr Chelsea Brain [Bioprocessing in microalgae]; Dr Georgina Robinson [Microbial-deposit feeder aquaculture bioremediation systems]; Dr Rebecca Martin [The adhesion of the barnacle Elminius modestus (Darwin) to fouling-release coatings]; Dr Adibi Rahiman Md. Nor [The effect of seaweed aquaculture cooperatives on sustainable livelihoods in Malaysia]; Dr Sana Akram Butt [Toxicity of engineered nanoparticles to marine bivalve molluscs]; Dr Muayad Al-karawi [Development and intensification of a foam flotation system in harvesting microalgae for biofuel]; Dr Abbas Umar [The screening, fabrication and production of microalgae biocomposites for carbon capture and utilisation]; Dr Leila Zhang [Renewable energy-assessment of pretreatment and co-digestion strategies to optimize methane production from microalgae] 

Completed MPhils: Josh Raine [Responses of the diatom, Navicula incerta, to intra-specific signals and nutrient availability]; Emily O'Hara [Exploring temperature sensitivity of nematocysts and the expression of toxin genes in the sea anemone Actinia equina, with preliminary analysis of the specificity of intracapsular fluid/venom composition]; Lucy Gorman [Assessment of the bioactivity of venom from the lesser weever (Echiichthys vipera) in alternative animal models]; Ilaria Spiga [Effects of anthropogenic noise on marine fish and invertebrates]; Paul Whitworth [Microbial ecology of seaweed-fed anaerobic digesters]

Esteem Indicators

Associate Editor for Invertebrate Reproduction and Development.


Undergraduate Teaching (from 2014/15)

  • MST1101 Marine Biology (Module Leader)
  • MST1104  Marine Study Skills
  • MST2104 Marine Research and Employability Skills
  • MST2105 Marine Practcal Skills
  • MST3102 Advanced Marine Zoology (Marine Poisons, Venoms and Toxins)
  • MST3104/05/06/07 Research Project 

Recent B. Sc. (Hons) projects supervised have included:

  • Mixture toxicity of metal ions to microalgae.
  • The microbiome of breadcrumb sponges: influence of water quality.
  • Developing a paper-based microalgae biocomposite.
  • Can hydrogels be used to securely ship microalgae?
  • Controlled bleaching of the snakelocks anemone.
  • Microbial communities living within cultures of aldehyde and non-aldehyde producing strains of the diatom Skeletonema marinoi.
  • Toxin-encoding gene expression in the beadlet anemone Actinia equina in response to thermal stress.
  • Is there a specific nutrient requirement for maximal bioluminescence in Pyrocystis lunula (Dinoflagellata)?
  • Diatom-derived polyunsaturated aldehydes and their potential effects on the Atlantic salmon (Salmo salar).
  • The role of bacteria in two nitrate-conditioned biofuel cultures of Nannochloropsis oculata.
  • Assessing the ability of Salinisphaera shabanensis and Navicula incerta to grow on flame retardant and antifouling coatings.
  • Can cells of the sponge Halichondria panicea grow on glass microfibre filter paper?
  • Tissue regeneration, spine biomineralisation and Notch signalling in the sea urchin, Psammechinus milers.
  • Impact of C:N manipulation on bacterial communities in sea cucumber-based bioremediation systems.
  • Does weever fish envenomation trigger oxidative stress?
  • Does antibiotic treatment affect the growth of Ulva fronds?
  • Effects of copper on the sea anemone Actinia equina in relation to reproduction, oxidative stress and histology.
  • Impacts of short-term exposure to diatom-derived unsaturated aldehydes on swimming behaviours of copepods and rotifers.
  • Effects of ibuprofen, diclofenac and sildenafil citrate (Viagra) on swimming behaviour in microalgae.
  • Is heat treatment effective at degrading venom from the lesser weever fish, Echiichthys viper?
  • Effects of nutrients, salinity, light intensity and temperature on growth rate and lipid production of a newly discovered chlorophyte, Tetraselmis indica.
  • Effects of organic and inorganic chemicals on growth and lipid content of microalgae.
  • The effect of temperature and copper stress on the population growth and protein expression of Tisbe battagliai under chronic and acute conditions.
  • Algal-bacterial interactions: A case study using Dunaliella salina
  • Assessing the growth of Ulva lactuca under cultivationand identification of epiphytic bacteria potentially responsible for thallus degradation.
  • What is the potential for hydrothermal carbonisation deployment in the Shetland Islands? 
  • The effects of cetyl trimethylammonium bromide (CTAB) and ozone on microalgae harvesting and lipid extraction.
  • Motility analysis of microalgae exposed to environmental toxicants.
  • Matrix Assisted Laser Desorption/Ionisation Time of Flight Mass Spectrometry (MALDI-TOF MS) as a tool for microalgae biotyping.
  • Effects of oxylipin exposure on microalgae motility.
  • Using three dimensional tracking spectroscopy to define the behavioural response of Artemia salina nauplii exposed to ultraviolet radiation.
  • Heterotrophic growth and lipid production in selected microalgae species.
  • Optimising culture conditions for carbohydrate yields from microalgae.
  • Incorporation of microalgae into functional microbial fuel cells.
  • Bioaccumulation of flame retardants in the marine food web. 
  • Metabolic exudates from Skeletonema marinoi induce bio-flocculation in marine microalgae.
  • The kinetics of nitric oxide generation throughout the culture cycle of the marine diatom Skeletonema marinoi.
  • Exploration of the swimming techniques based on physiology and hydrodynamics of a juvenile white beaked dolphin (Lagenorhynchus albirostris) using mimic tail design and testing.
  • The fatty acid profile of Capitella sp. for use in commercial recirculating aquaculture systems.
  • Analysis of the amino acid composition in Capitella sp. using Ultra-High Performance Liquid Chromatography.
  • Optimising nutrient levels and harvesting frequency during the culture of Nannochloropsis oculata for biofuel production.
  • Anaerobic digestion of Laminaria digitata and co-digestion with glycerol.   
  • Effects of diatom-derived polyunsaturated aldehydes on the motility of Nereis virens sperm. 
  • Activation of vesicular sperm from three species of barnacle through the elevation of seawater pH.