Red-billed gulls

red-billed gull

Red-billed gulls are fond of nesting on roof-tops of coastal buildings and have always been residents of Oamaru. By working together to make buildings less attractive for breeding, and by reducing the food available in town for gulls, we can minimise the conflict between gulls and people. Waitaki District Council is available to provide advice and guidance on how to gull-proof your property.

First though, it’s only right to note red-billed gulls are a bit special. They seem abundant, but actually they’re in decline nationally (numbers are 50% down over the last 25 years). Like the kakapo, takahe and kiwi, they are a protected species. The maximum penalties for disturbing wildlife are up to 2 years in prison or a $100,000 fine, or both. Oamaru is a coastal area which means we’re encroaching on their natural habitat. Gulls nest in urban areas all over the world and it’s common to have gulls nesting in coastal towns.

For information on Red-billed gulls, their breeding habits and ecology, visit

A guide to keeping your roof free from nesting gulls

Nesting gulls on your roof can lead to expensive repairs, clogged gutters and noisy neighbours for up to five months. If this sounds like a nuisance, acting fast (and early) means there are things you can do to discourage them from breeding on your building. 

It is ILLEGAL to disturb gulls once they have active nests (eggs or chicks). Any measures to deter gull nesting should be in place by July/August. Gulls are creatures of habit and will return to a successful nesting ground, year after year, but any rooftop is a potential new site. If an old site is no longer available, they will move and not necessarily to the building next door.

Breeding Season plan

Red-billed gulls start laying eggs from September through February so you need to put measures in place by July/August at the latest, when they will be looking for attractive real estate to develop and build nests on. Gulls can bring in materials and start making nests very quickly when they get going, and once they have eggs or chicks on the nest there isn't much you can do.


  • Decide who is responsible (usually the building owner/landlord) and ensure they are aware of the potential costs if gulls start to nest.  Many landlords do not live in Oamaru and so communication is vital between the landlord and the tenant who often act as the eyes and ears (and nose) on the ground.  
  • Whoever is responsible, identify and exclude parts of roof attractive to nesting gulls.  These are flat ledges, gutters and flat roof surfaces, small walls or parapets that provide shelter from the wind and high points that can act as lookouts for birds. If thelandlord cannot carry this out, contact Council for a list of roofing contractors in Oamaru who are now familiar with red-billed gulls, their protection status and ways of managing them and can provide assistance and advice.   

September to February

  • As part of normal maintenance schedule regular checks of roof surfaces and gutters from September to February and remove any material before it has an egg or chicks.
  • Gulls can arrive and start nesting quickly so if you think you see more one day, get up and have a look before it’s too late.  
  • If you find gulls with eggs or chicks contact DOC (0800 DOCHOT) so they can advise on the best way forward.  It is illegal to disturb/remove breeding red-billed gulls.

Rest of the year

  • Normal roof maintenance applies but in a town by the sea, birds could be congregating on any night of the year on your roof, and in large numbers – keep checking gutters.

Don't encourage them

  • Don't feed them, it only makes them want to stay
  • Ensure bins are not accessible food waste is covered.  Restaurants and cafes: try to keep food covered and don’t give them your last chip.  They need natural food and still rely on this for feeding during the breeding season – they don’t need your chips.
  • Turn lights off at night. Seabirds are attracted to artificial light sources, so reduce this where you can.


  • Red-billed gulls will eventually become habituated to most deterrents, so it’s important that whatever tool you use is monitored to ensure it is effective and is able to be stopped if habituation starts to occur.  
  • There is no such thing as an “install and walk away” tool or technique that will discourage gulls from nesting on your roof, but there are a range of options that if used correctly and checked regularly can be effective. 

DO NOT use commercially-available Class 4 laser bird scarers – they have been shown to cause irreversible eye injuries to birds.  Local experience has found that other tools available are cheaper and more effective at deterring nesting gulls.  We only want to deter them from nesting on Oamaru’s roofs, not to harm them.

Tools to discourage gulls from nesting on roofs

Motion detected sprinkler systems


  • Proven effective at keeping gulls from landing on several Oamaru roofs.
  • Relatively affordable compared to other options.    
  • Easily modified to cover a larger roof area or ridge. 
  • Motion detectors ensure more sudden start/stop of water and sprinkler movement, which reduces the chance of habituation. 
  • Local contractors now familiar with effective setup of these systems. 

Bird Spikes

  • Installed on ledges and tops of parapets.   
  • The full surface must be covered in spikes as gulls will stand next to them if they have a chance. 
  • Choose the spikes designed for larger birds.

Hawk kites, wire with flags and tassels

  • Can be enough to move birds on but should be monitored and brought in if becoming less effective.      
  • If hawk kite is put up and left in the same spot gulls will eventually become used to it. 
  • They deteriorate over time so again only putting it up when necessary reduces the chance it will get damaged during high winds.
  • Wire with flags or tassels can be run along longer edges to reduce the chances of birds landing.

Orange builders fencing, netting, mesh 

  • Needs to be installed over larger flat areas to discourage gulls from landing and building nests. 
  • Access should be maintained for regular checks as in some instances birds will nest over gutter mesh and grills. 
  • Fine net/mesh should be avoided as it damages easily and risks catching and harming wildlife. 

Sonic bird scarers 

  • Don’t seem to stop gulls from using roofs in Oamaru.
  • Consider other options before purchasing these devices as they are relatively expensive and eventually the birds will get used to them.

Remember, all methods should be monitored after being put in place to ensure they are effective - if the tool is failing it should be quickly stopped and changed.

Local contractors who can help

Talk to local contractors endorsed by DOC in relation to dealing with Seagull issues specifically. They are available to provide services regarding gull proofing, installing deterrents and helping you understand the process if you come across active gull nests.