"Feral pigs are one of the most destructive animals in the state; they continue to be a serious threat to our native bird habitats and our native rainforest. Feral pigs are a major factor in rainforest degradation."These are the words of George Masesengale a member of the Audubon Society in Hawaii, on the impact of feral pigs on rangelands, which was published on 25th March 2008 on the honoluluadvertiser.com (http://the.honoluluadvertiser.com/article/2008/Mar/25/ln/hawaii803250318.html).
According to this post, law makers and environmentalists were calling on the Hawaii state government to explore tactics that would aid in the control of the feral pig population in urban Honolulu. Some of the measures proposed by the legislation was the expansion of game management as well as public hunting areas, extending the hunting season as well as provision of incentives for hunters.
Another organ, DLNR was reported to have already begun an initiative of ending the menace and was pointing to an ongoing program of hunting in Manoa, Tantalus as well as Makiki which had successfully snagged over 50 pigs in a span of one year alone.
Such is the menace that the feral pigs had caused the State of Hawaii. So serious is the issue that the forest system and rangelands have been destroyed by the ballooning invasive species in the recent past. This paper is specifically geared towards exploring the impact of these pigs on rangelands and further explaining the ways of managing them. Some of the impacts that will be discussed include the destruction of the ecosystem and forest cover while the management methods will include these that are already in place, as well as the use of technology in managing the same.
In order to fully understand the impact of feral pigs in Hawaii, it’s imperative that the activities as well as the behavior and diet of feral pigs are discussed. First and foremost, feral pigs are blamed in Hawaii for the extinction of flightless birds and other nesting species, since they feed on eggs of these birds, making it difficult for the birds to multiply, as well as the spread of epizootic infections and diseases among rare birds, increased mosquitoes population as well as extinction of some plants
A scientific analysis of the feral pig stomach revealed that the animal feeds significantly on the Hapu plant, as well as other species of ferns. In order to feed on some of these plants, pigs normally uproot them, so as to get to the inner pulp, which has been a major reason for the near extinction of some of these native plants in the rangelands (Mandy, et al 2009).
These feral pigs also feed on other items such as grasses and sedges, worms and insects, soils and mud as well as litter. They also feed on fruits as well as berries, passion fruits, guavas as well as non native weeds. This has led to the spread of toxic plants all over Hawaii as a result of their feeding activities. These weeds have been a major destruction of rangeland plants.
According to a report carried in a local newspaper, through the above mentioned activities, feral pigs have the ability to alter the community of vegetation present. They normally compete with native wildlife for the available food, and since they are normally more adapted to many areas and generally more aggressive, succeed in causing extinction in quite a number of them. Additionally, feral pigs have been reported to have destroyed range lands by uprooting may trees in search of food, which has had devastating impacts in Hawaii.
Management of feral pigs
The above discussion has shed light on the negative impacts of these animals on the rangelands as well as other parts of the ecosystem. A continuing discussion has been just how best to manage these animals. The discussion that follows attempts to inform of the various means of effectively managing these animals
Some of the most commonly used methods by range owners and managers are aerial shooting and baiting, which are very efficient and cost effective means of managing them. In these methods, the pigs are shot from above; as well as having dangling baits that can easily catch them. These methods are normally more effective especially with a vast and remote landscape.
More localized areas may call for fencing or even ground bating. Other methods include snaring, a method that has been argued to be ineffective and even counterproductive in that it causes the trapping of unintended animals rather than the pigs.
Hunting of the feral pigs is a very popular method of managing these pigs and especially in Hawaii. As explained in the onset of this paper, the lobbyists insist on the government legislating to allow for expanded hunting land, as well as hunting hours and season. This is believed to be an effective method of reducing the population of these swine’s (Parkes, 2010).
Other proposed measures include biological control. This is a method in which a predatory animal is introduced amongst the feral pig population, or even the introduction of a disease that would wipe them away. Critics however argue that introducing a disease could be detrimental, even counterproductive in that it could end up spreading to even farms here edible swine’s are bread, leading to huge losses.
Are these methods worth it, are they even feasible?
Federal pigs’ hunting is a licensed sport in Hawaii that earns the government a large amount of revenue that cannot just be wished away. Hunter’s provide direct income to the Hawaii government. Information available from the states wildlife department indicates that hunting alone generated just above 20 million dollars as of 2006, which is besides the associated income such as transport, camping and lodgings. This is a significant amount of contribution to the national kitty. Additionally, feral pigs are utilized by the local communities as supplement to their diet.
It must also be understood that feral pigs like any other animals in the wild have a ‘right’ to existence. The law of nature allows for natural attrition and it should therefore be allowed for nature to decide their fate. Animal rights groups should therefore step in to ensure that even if there is legislation to manage the pigs, their elimination should be done in a considerate manner.
The above discussion has delved into the impacts of these animals on the rangelands as well as other human endeavors. These have included the causing of diseases to other animals, feeding on and falling plants as well as generally harboring disease causing organisms. Various methods of control and management of these animals have also been discussed, although the list is not conclusive.
It has also been noted that any efforts to eradicate the population of feral pigs will not fail to meets its fair share of challenges, since there is a lot of economic benefits associated with the animals. Besides these challenges, it must be understood that the task of managing these animals may be larger than expected, and all parties involved must be prepared for a huge battle with the feral pigs (Case, 2007). Besides the technical and even legal challenges of carrying out some of the eradication procedures, Its important to note that the cost of eradicating this animals is deterrent.
While the government has managed for instance to build fences that would effectively manage the additions or entrance of new feral goats, it’s not an easy task to construct a fence that would be able to withstand the strength of the feral pigs.
In conclusion, efforts to manage these feral pigs would have n impact, let alone succeed, only if all stakeholders, starting from the farm owners, hunters as well as the state government, are committed to work together to eradicate this troublesome species of swine’s.
Parkes JP (2010), Ramsey Rapid eradication of feral pigs (Sus scrofa) from Santa Cruz Island, California.
Ramsey D. S et al (2009). Quantifying eradication success: the removal of feral pigs from Santa Cruz Island, California. Conservation Biology 23:449–459.
Nogueira-Filho S, et al ( 2009) Ecological impacts of feral pigs in the Hawaiian Islands. Biodiversity and Conservation 18: 3677–3683.
Mandy C. B. et al (2009) Evaluation of feral pig control in Hawaiian protected areas using Bayesian catch-effort models
Tyler A. C. (2009) Feral swine damage and damage management in
forested ecosystems.Wildlife damage management centreHonolulu
Honoluluadvertiser.com (2008): retrieved from (http://the.honoluluadvertiser.com/article/2008/Mar/25/ln/hawaii803250318.html