Kevin Parsons, national operations manager for Globe Pest Solutions, explains why birds are a true pest, and more than just a nuisance.
The problems caused by birds in ports and marinas should not be underestimated. Not only do they carry diseases but they can also damage port buildings and shipping, causing public health issues and creating safety hazards. Mark Wenman, technical manager for Network Bird (who market a range of bird protections products such as Avipoint Bird Spikes (main picture, above), Avishock system and Network Bird Nets), highlights the bird impacts and control solutions for bird problems in UK ports.
The key bird pests found in and around UK ports can cause significant economic damage. The predominant species are pigeons (Columba livia) and herring gulls (Larus argentatus). Bird droppings are acidic which means that they can react with metals on port structures and shipping, as well as certain building materials such as stonework, which leads to increased corrosion and erosion. From an appearance point of view, port buildings and ships covered in bird fouling look unpleasant and can smell, generally projecting a poor image.
These would be the obvious impacts of a bird problem, but there are other significant but often less obvious impacts.
From a safety point of view, large amounts of droppings can make walkways and staircases slippery, posing a slip hazard and seagulls can also be very aggressive and will readily attack people or pets – there have been a number of cases where serious injuries have been caused by gulls. Of course, birds are known for spreading various diseases.
Risk of disease
There is evidence that birds carry a wide variety of disease-causing organisms such as Salmonella, Listeria and E.coli. The chances of catching these diseases directly from birds are fairly remote, poor standards of hygiene after contact with bird droppings significantly increase the risk. Much more serious is the potential for inhalation of the air-borne disease agents that these birds can carry, such as Psittacosis; such respiratory diseases on occasions can be fatal.
Birds that gain access to food storage premises, such as grain stores, can contaminate food with their droppings, feathers or nest materials. Legislation controlling such contamination varies from country to country, with some requiring bird-proofing of food premises by law. However, one thing is certain, if there is any contamination with bird droppings or feathers, the likelihood is that legal action will be taken. “In Liverpool docks back in 1984, there was a feral pigeon infestation in the grain storage areas,” recalled Mr Wenman. “It is believed that diseased pigeons infesting the food stores, infecting the grain with highly contagious Newcastle disease. There were 19 outbreaks of the disease and one million chickens needed to be slaughtered as a result.”
Slowdown of operations
Cleaning up gull droppings on shipping and yachts in marinas takes both time and money. In Cornwall for example, sailors on the local lifeboats were spending 20 minutes cleaning gull droppings off the deck before it was safe to set sail.
“Slowing up the launch of a lifeboat because it needs to be cleaned, was an unacceptable situation,” said Mr Wenman. “Fortunately we were able to proof the boats with netting which hung down the sides of the boat. It now only takes 30 seconds to gather the net up and stow it prior to launching.”
Options for bird control
As with any pest control problem, the starting point for bird management is to try to remove the conditions which allow the birds to become a pest. This means denying the pest species access to food and harbourage. In ports where there are large populations of seabirds, having a bird management strategy is important. Such a strategy may include the continued implementation of strict hygiene and housekeeping standards, proofing with exclusion systems to keep the birds out, scaring the birds and finally, where absolutely necessary and only where it is legally allowed, culling specific persistent individuals.
Hygiene, housekeeping and exclusion
Preventing access to food supplies is often the key to controlling a population of birds, such as pigeons, which might frequent stores at ports. Where birds are flying into a building, basic housekeeping is a starting point, for example, ensure that un-proofed doors and windows are kept closed. Bird proofing is required for other areas.
Mr Wenman recalled a typical issue at Pool harbour in the UK. “There were real problems with gulls returning to the previous year’s nesting sites on harbour buildings. We were asked to provide technical advice for proofing some of the buildings. This involved designing systems that successfully excluded the gulls from the asbestos cement roofs whilst ensuring that the integrity of the roofs was maintained. We recommended some of our qualified bird specialists to install the proofing which successfully resulted in a reduction in the size of breeding colony in that part of the harbour area.”
Whatever method is chosen, it makes good sense to go back to the site after installation to check that no birds are trapped or eggs left. It is also important to understand that regular inspection, once or twice a year, is essential to make sure the installation continues to work effectively. All bird management systems can be susceptible to damage by both people and the weather. They can also collect debris which may need to be removed.
In specific situations, using other birds or imitations to mark their territory can prove successful. The use of these techniques requires specialist knowledge and training. Acoustic scaring techniques have been successful with crows and gulls by using recordings of the birds’ own distress calls. Flying predator birds can be effective in some situations. Predator kites and Eagle Eyes can work in some circumstances, although the systems need to be part of an overall bird management program.
“As well as the proofing work at the harbour, we recommended looking at some of the commercial properties bordering the harbour area, along with installing an acoustic deterrent control system in conjunction with flying live birds of prey. Using both systems together produces far better results, as the association between the sound and seeing the falcon gives a much stronger deterrent effect on the birds,” advised Mr Wenman.
It is sometimes necessary to cull specific, problem birds. Where this is the only option it must be done within the law and as discreetly as possible to avoid any public relations difficulties. Remember large scale culls are rarely, if ever, successful – immigration from other flocks and rapid reproduction mean numbers soon recover.
A successful bird management program is likely to require an integrated approach combining some, if not all, of the elements outlined, backed up by a regular maintenance contract for a lasting solution. Bird management is a specialist activity and not all pest control companies are equipped to tackle this problem. If you are looking to expand into bird management, Globe Pest Solutions can provide the specialist advice to set you on your way.
Kevin Parsons, National Operations Manager, Globe Pest Solutions