School of Marine Science and Technology

Staff Profile

Dr Gary Caldwell

Senior Lecturer in Applied Marine Biology



Dr Caldwell is Senior Lecturer in Applied Marine Biology.

Roles and Responsibilities

'Marine Resources and Renewable Energy' research group leader.

Deputy-director for MaST postgraduate research.


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.


British Phycological Society

International Society of Invertebrate Reproduction and Development

Challenger Society for Marine Science

International Society for Applied Phycology

Fisheries Society of the UK


Research Interests

Google Scholar profile

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


I am active in the continued development of algae (both micro- and macroalgae) as potential sources of marine biofuels and bioactive products. There are active programmes in seaweed culture, seaweed anaerobic digestion (including the £2.8 million InnovateUK SeaGas project); microalgae culture management for high value chemical and biodiesel production (including the Euro 3.4 million H2020 project, Living Architecture); microalgae bioflocculation and harvesting; and energy production from marine biomass wastes. Recent work has focused on proteomic studies of microalgae, their grazers and associated microbial flora using MALDI-TOF-MS. I am also using Next Generation Sequencing to study the microbiome of algae cultivation systems. 

Interests relate to plant-plant and plant-animal interactions which are mainly modulated by chemically driven processes, principally through the production of toxic metabolites and/or the production of non-toxic but otherwise biologically active compounds. I am especially interested in the role of algal-derived compounds in driving aquatic food webs and their potential development for biotechnological and pharmaceutical exploitation. Recent work has concentrated on the functioning of bioactive diatom-derived polyunsaturated aldehydes in regulating the reproductive success of invertebrates. I am interested in both the factors and processes contributing to the formation and release of algal-derived bioactive molecules and the physiological and molecular responses of the target animals in respect of toxic endpoints and detoxification/cellular repair mechanisms.

I am interested in the biological response of organisms following exposure to xenobiotics and marine venoms. 


I am currently working on the microbiomes associated with sea cucumber, seaweeds and macroalgae.

Current Postgraduate Supervision

Abdulbaset Abuissa (PhD) - Assessment of combined effects of ocean acidification and metal toxicity on selected marine invertebrates. 

Muayad Abed Shihab Alkarawi (PhD) - Approaches for converting algae oil to fuel. Co-supervised with Dr Jon Lee. 

Sana Akram Butt (PhD) - Toxicity of manufactured nanoparticles to marine biota. (Pending corrections).

Lucy Gorman (MPhil) - Exploring the venom of the lesser weever fish, Echiichthys vipera. Co-supervised with Dr Sarah Judge.

Warm In-Na (PhD) - Development of sustainable algae biocomposites for carbon capture. Co-supervised with Dr Jon Lee.

Fern Lyne (MPhil) - Gene expression in copepods feeding on toxic diets across multiple generations. Co-supervised with Prof. Tony Clare and Dr Knut-Erik Tollefsen.

Rebecca Martin (PhD) - Silicone fouling-release coatings: Physical effects on the adhesion of marine fouling invertebrates with particular emphasis on membranous–based barnacles. Industry funded PhD studentship (International Paint) co-supervised with Prof. Tony Clare. (Pending corrections)

Alfonsina Milito (PhD, Open University) - Ovothiol, a marine antioxidant: discovery of its biological activities. Co-supervised with Dr Anna Polumbo and Christophe Brunet.

Belinda Njumo (PhD) - Developing algae biofuel technology for Cameroon. Co-supervised with Dr Ethan Hack and Dr Thomas Howard.

Emily O'Hara (MPhil) - Nematocyst and venom analysis in sea anemones. Co-supervised with Prof. John Bythell. 

Adibi Rahiman (PhD) - Innovative solutions to optimize seaweed aquaculture in Malaysia. Co-supervised with Prof. Selina Stead and Prof. Tim Gray.

Josh Raine (MPhil) - Chemical ecology of diatom motility. Co-supervised with Prof. Tony Clare. (Pending examination)

Ilaria Spiga (MPhil) - Video and acoustic observations of the effects of anthropogenic noise in coastal areas.

Abbas Umar (PhD) - Novel approaches to continuous microalgae harvesting. Co-supervised with Dr Jon Lee. 

Paul Whitworth (MPhil) - Microbial ecology of seaweed-fed anaerobic digesters

Leila Zhang (PhD) - Renewable energy-assessment of pretreatment and co-digestion strategies to optimize methane production from microalgae. Co-supervised with Dr Paul Sallis.

Completed PhDs under my supervision: 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].

Esteem Indicators

Associate Editor for Invertebrate Reproduction and Development.

Member of Council, British Phycological Society. 


Current funding sources include:

Innovate UK, BBSRC, EU H2020

Other funding sources remain confidential.

Industrial Relevance

The majority of my work is industry orientated, particularly in the area of marine bioenergy and biotechnology.


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:


  • 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.