Boat at sea during the night.

How to mitigate marine light pollution

Introduction

Find out about mitigation measures for light pollution at sea.

Many seabirds get disorientated by artificial lights at night, which can lead to collisions with vessels (vessel strikes).

Following vessel strikes, seabirds can be contaminated with chemicals on deck, such as oil or fuel. This causes loss of waterproofing and subsequent drowning.

Vessel strikes can also cause direct seabird deaths. The risk of vessel strike is highest during foggy and rainy nights.

How to reduce seabird vessel strikes

We recommend taking the following actions, while maintaining vessel and crew safety.

  • Minimise marine light use, especially spotlights and floodlights, when you are within 5 km of an offshore island, where most seabird colonies are located.
  • Avoid unnecessary movements and activities at night.
  • Eliminate unnecessary lights.
  • Shield lights to only light areas essential for safe operations.
  • Use lights with reduced or filtered blue and violet wavelengths (2200 K or less).
  • Use black-out blinds wherever possible.
For commercial fishers 
  • Follow your protected species risk management plan and operational procedures.
  • Contact your liaison officer for more information.

Advice sheets

2022:
2019:

What to do when vessel strikes occur

  • If birds land on vessels, assess them quickly.
  • Practice safe seabird handling techniques.
  • If they are feisty with no obvious injuries, release them safely over the side of the ship.
  • If they are stunned or injured, hold the birds in boxes (if possible, one bird per box and keep boxes shaded).
  • Release any birds that have recovered after resting in boxes.
  • If birds don’t recover, inform port authorities to arrange pickup by DOC or local bird rescue staff.
  • If the ship is heading out to sea and won’t be in port the next day, release all birds overboard regardless of their injuries.

See protected species handling and release guide. 

Provide photos and notes about seabirds

You can support our data and research. 

  • Take two photographs of each bird prior to release; close-up of the bird’s head from the side and the entire bird showing the underwing pattern.
  • Keep records of date and location where birds came onboard and weather conditions at the time.
  • Note if the bird was alive and unharmed, injured, or dead.
  • Send photos and notes to marine@doc.govt.nz.

Contact

If in doubt, you can call the DOC emergency hotline 0800 DOC HOT (0800 362 468).

Or you can email marine@doc.govt.nz. 

More information