Conserving the Wirebird (Charadrius sanctaehelenae)
The critically endangered Wirebird is St Helena’s only surviving endemic bird. It is a small plover, which attracts a great deal of interest from the local community as well from visitors. There are currently only 322 individuals to be found on the island, which means on a global scale not only is it a very rare species but the population is by no means safe from extinction
The Wirebird likes to feed on a variety of ground-living insects, especially beetles, which it catches using a ‘run and grab’ technique. Changes in farming practice means there is less pasture land for Wirebirds to use as their feeding and breeding territories. Wirebirds are very territorial and ‘take command’ of an area between 50 – 100 sq.m. to guarantee sufficient food resource before breeding.
A reduction in suitable terrain for territories is as much of a threat to the Wirebird population as the feral cats, Mynah birds and even sheep that prey on chicks and eggs. The land-take for the proposed airport and related construction work will also have an affect on Wirebirds and their habitats.
The good news is that the Air Access Project agreed in June to implement the Wirebird Mitigation Plan. Essentially, the aim is to establish Wirebird habitats in suitable adjacent locations to compensate for the loss of habitats resulting from airport construction and related work.
An enduring benefit from the agreement supporting this project is that a framework and formula has been established which can be used when negotiating in similar situations where a development has an adverse impact on Wirebird habitats.
Wirebird behaviour is fascinating and really has to be seen at first hand. They will deliberately lure a predator away from the nest by running at speed as soon as it detects a threat and also by doing what is called its “broken wing display” where the bird mimics a broken wing dragging it along the ground. Wirebirds use a similar distraction strategy to protect new-born chicks. However, a chick will feed itself about two hours after hatching. The parent birds remain in the territory to protect the chicks for about 35 days, after which time the chicks have fledged. During the breeding season juveniles act as sentries and warn of potential predators to the parent bird’s territory.
Wirebirds can be found above and around the Central Basin of Prosperous Bay Plain, a semi-desert landscape. It also favours locations such as Deadwood Plain (a dry pasture) and Broad Bottom (a wet pasture).
Work on behavioural research and habitat conservation is supported by the Royal Society for the Protection of Birds (RSPB) and the Overseas Territories Environment Programme (OTEP). Research is ongoing into breeding, distribution and the success of Wirebirds in differing habitats. To protect them successfully, much more needs to be known about this unique and captivating bird.
(Chris Hillman, written in 2011)