Herring Gulls - Control of Roof Nesting

This page contains the following information about Herring Gulls:

Introduction
The Problem
Natural History
Long Spikes
A Word of Warning
Control of Food Sources
Proofing of Buildings
Further Help
Contact Information

Introduction

Herring gulls now commonly rest on roof tops in many coastal towns and villages. Roof nesting by herring gulls is a fairly recent phenomenon. Since the 1970s the number of roof nesting gulls has steadily increased, as has the number of complaints received by the Council.

There are several species of gulls which can be seen locally and to many people they are all just 'seagulls', but in our area only the herring gull commonly nests on buildings. It should however be noted that occasionally other birds that might be mistaken for herring gulls can nest in built up areas.

The Problem

Many people who have gulls on their property find they cause a nuisance and commonly cited problems include:

Noise: caused by calling gulls and by their heavy footsteps.
Mess: caused by their droppings, fouling of washing, gardens and people.
Damage to property, caused by gulls picking at roofing materials and by nests which block gutters or hold moisture against the building structure.

Sometimes more serious problems occur:

Birds can dive and swoop on people and pets. This usually occurs when chicks have fallen from the nest and adult birds attempt to prevent them coming to harm by frightening away potential threats.
Blockage of gas flues, valley and parapet gutters by nesting materials. The former can have serious consequences if gas fumes are prevented from venting properly, or if flooding occurs as a result of blocked gutters.

Natural History

The majority of people who have gulls nesting on their property don't refer to them has herring gulls but as 'seagulls', because most of us do not stop to differentiate between one type of gull and another. But most species of gull do not nest on buildings and, in our area only the herring gull does so commonly.

Herring gulls are large birds. They are, in fact, about 55 cm (22") from bill to tail with a wingspan of about 85cm (34").

Breeding pairs court in April and commence nest building from early May onwards. In towns, the nest is constructed from straw and grass, twigs, paper and any other material the gull can conveniently use. The nest can be quite large and, if made of material accumulated over several years, very heavy.

Eggs are laid from early May onwards with two or three being the usual number. The eggs take about three weeks to hatch so the first chicks are generally seen about the beginning of June.

Long Spikes

Long spikes may be fitted to the chimney stacks of properties where herring gulls nest. It is up to owners to arrange to have the spikes fitted, which is a job generally best left to a competent builder or roofing contractor. It is important to fix sufficient spikes to ensure that the nesting area is well covered. We encourage property owners who wish to use this method to obtain plenty of spikes.

A spiking system can be used to prevent herring gulls nesting on top of chimney stacks between the pots, and in the valley behind a chimney stack where it meets the roof.

The basic methods of use are as follows:

Chimney top fixing

The surface to be treated, usually the cement flaunching between the chimney pots, should be brushed clean with a wire brush. The spikes are then bent into the required shape and placed in position on a dab of mortar. A further dab of mortar is then used to secure the spike assembly.

We recommended the use of a PVA (or similar sealant) compound to assist adhesion of the mortar to the chimney stack.

Chimney back fixing

Herring gulls sometimes nest behind chimney stacks where the chimney meets a sloping roof. The valley formed is often warm and sheltered from the wind and makes an ideal nest site.

It is difficult to place spikes at the base of the valley because the fixing can interfere with the structure of the roof.

It is possible to suspend the spikes from the chimney stack using the longer centre rod. The usual fixing method is to screw the spike on using a masonry plug and screw with a stout washer to trap the spike against the masonry.

The list of birds against which humane methods may be used includes herring gulls.

Only the owner of a building or the occupier can take action against the herring gulls on it, or they can give someone else permission to act on their behalf.

In practice there are very few humane methods to kill birds which are likely only to affect a particular species and skill and experience is needed to deploy them. The Council would discourage people from attempting to kill herring gulls which nest on their property.

The Council is particularly keen to discourage shooting of roof nesting herring gulls, as this is neither humane nor safe.

A Word of Warning

Whilst the gulls which nest on buildings are usually herring gulls there are several other gull species which occasionally nest on buildings. Lesser Black Backed Gulls, may also nest on roofs in the South of England. They are very similar in shape and size to herring gulls but darker in colour.

Lesser Black Backs can lawfully be moved in the same way as herring gulls. Some conservationists argue that they nest so rarely in towns that they should be left undisturbed.

If you have any doubts about what kind of 'gull' is nesting on your property ask someone who knows. Our own staff are able to offer assistance if required.

Control of Food Sources

Colonies are undoubtedly encouraged to develop by regular feeding. If gulls are fed regularly it will create an artificially high population and encourage further breeding pairs to take up residence in an area. A natural population level will only be established if the gulls are left to fend for themselves from natural food sources. Gulls will also scavenge readily on poorly stored refuse. You are strongly urged wherever possible, use heavy duty plastic or steel refuse containers with close fitting lids. The practice of leaving rubbish outside in plastic sacks will provide a plentiful food supply and must be avoided.

Proofing of Buildings

All owners/occupiers of buildings which have, or may attract roof nesting herring gulls are strongly urged to provide the building with deterrent measures suitable to the individual building. This section tells you how to do so.

If as many owners/occupiers as possible apply deterrent measures to their buildings, it may be possible to reduce or break-up the colonies of birds.

Also, deterrence may well provide relief to individual occupiers.

The principal methods of deterrence are:

Fitting of long spikes to nesting locations such as chimney stacks.
Fitting of short spikes, contained in a special plastic base, to nesting locations such as dormer roofs.
Fitting of wires or nets to prevent herring gulls landing.
Disturbance of nesting sites including removal of nests and eggs

Further Help

If the proofing work required is of a difficult nature you may wish to consider contacting one of the following companies who are all members of the British Pest Control Association. They may also supply specialist bird proofing materials to install yourself, or have them installed by your builder.

Greenhunter Limited
Unit 30, Bolney Grange Business Park
Stairbridge Lane
Bolney
Haywards Heath
West Sussex
RH17 5PB
Telephone: 01444 246224
Fax: 01444 242957

EnviroGuard (UK) Ltd
Leicester Square
Penshurst
Tonbridge
Kent
TN11 8BJ
Freephone: 0800 328 8464
Telephone: 01892 870164
Fax: 01892 870062
Website: www.enviroguard.co.uk

Rentokil Initial UK Ltd
Rentokil House
Hart Street
Maidstone
Kent
ME16 8RH
Telephone: 01622 679821
Fax: 01622 661206

Contact Information

Please contact us for further advice or information on any matter relating to Environmental Protection.

This page last updated: 30/07/2008

Environment and Planning

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