ALaNoR – Artificial Light at Night on Reefs

3 minute read

Lighthouse at night

Artificial light at night is a globally widespread environmental pollutant with direct ecological impacts on all levels of biological organisation across both terrestrial and aquatic ecosystems. Approximately one-tenth of the world’s population (600 million people) live in coastal areas that are less than 10 m above sea level, resulting in considerable anthropogenic light pollution, which is expected to increase in parallel with global human population increases along the world’s coastline.

While light pollution is a recognised threat to terrestrial wildlife and biodiversity worldwide, directly affecting biological and ecological processes across taxa, including changes in key life-history traits, such as immune function, survival, ageing and fecundity, the impacts of ALAN have rarely been assessed for marine species in the wild.

Artificial light at night likely impacts many marine species which have evolved biological rhythms based on natural light cycles, the strongest and most predictable of environmental cues. Cues from circadian, circalunar, seasonal and annual rhythms are vital for biological processes such as reproduction, and dispersal. Natural light regimes may be compromised by ALAN, directly disrupting physiology, behaviour and reproduction in many marine organisms. Despite the potential for ALAN to strongly disrupt such processes, only two laboratory studies have been undertaken to date, meaning the impacts of ALAN on coral reefs remains largely unexplored. A recent collaborative long-term field study led by the two Principal Investigators found that ALAN reduced juvenile clownfish survival and growth. As the light pollution was representative of levels recorded on fringing reefs, but less than in ports, impacts on marine ecosystems are likely even greater, and research in this area is desperately needed.

Project goals

The aim of these PhD projects is to quantify the fitness consequences of exposure to ALAN on adult reproduction, egg traits and larval traits associated with dispersal. Reproduction and dispersal are vital processes for population persistence and determining how they are impacted by ALAN is essential for managing light pollution and conserving biodiversity on fringing coral reef ecosystems.

The CNRS project will investigate how artificial light at night impacts on spawning behaviour, spawner physiology, reproductive phenology, and larval traits in coral reef fishes.

The University of Melbourne project will investigate how artificial light at night (ALAN) impacts on larval settlement, post-settlement growth and survival, recruitment, and self-recruitment of coral reef fishes.

Supervision team

The University of Melbourne: Professor Steven Swearer

*Click on the researcher's name above to learn more about their publication and grant successes.

Paris Sciences et Lettres University (PSL): Suzanne Mills

Who we are looking for

We are seeking a PhD candidate with the following skills:

  • Demonstrated experience in the field of marine biology, ecology or environmental science.
  • Demonstrated experience with scientific diving.
  • Demonstrated experience with experimentation on fish in the laboratory (CNRS project) or in the field (UoM project).
  • Demonstrated ability to work independently and as part of a team.
  • Demonstrated time and project management skills.
  • Demonstrated ability to write research reports or other publications to a publishable standard (even if not published to date).
  • Excellent written and oral communication skills.
  • Demonstrated organisational skills, time management and ability to work to priorities.
  • Demonstrated problem-solving abilities.

Further details

  • The PhD candidates will benefit from the combined expertise of the project supervisors, and the embedding into two research environments.
  • Professor Stephen Swearer at the University of Melbourne will contribute expertise in the manipulation and measurement of marine light pollution and in larval dispersal, settlement and recruitment. Dr Suzanne Mills will contribute expertise in the coral reef ecosystems of French Polynesia and in animal behaviour and endocrinology.
  • Two PhD projects are available. One candidate will be based at UoM with a minimum twelve-month stay at CRIOBE. The CNRS candidate will be based at CRIOBE and will spend a minimum of 12 months at UoM.
  • The candidates will be enrolled in the PhD program at Paris Sciences et Lettres University and the PhD program at the School of BioSciences at the University of Melbourne.

To apply for this joint PhD opportunity, and to view the entry requirements, visit How to apply.

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