Kaimanawa Horse - Population Control and Study

Population Control and Study

Due to the increase in population after protective legislation was put into place, the Department of Conservation developed a management plan for the Kaimanawa herd in 1989 and 1990. A draft plan was made available to the public for comment in 1991, and the public made it clear that it objected to herd reduction through shooting from helicopters, and instead favored the horses remaining alive after being removed from the herd. However, core animal welfare groups felt that shooting was the most humane option. Trial musters were conducted in 1993, 1994 and 1995, and were successful, although costly and with a limited demand for the captured horses.

In 1994, a working party was established to look at the management of the Kaimanawa herd. They aimed to decide which organization was in charge of long term management, to ensure that the treatment of horses is humane, to preserve and control the best attributes of the herds, and to eliminate the impacts of the herds on other conservation priorities. Goals included ensuring the welfare of the horses, protecting natural ecosystems and features that the Kaimanawa herd may impact and keeping the herd at a sustainable level. Ecological objectives included ensuring that Kaimanawa horse does not adversely affect endangered, rare and biogeographically significant plants; ensuring that the herd does not further degrade the ecosystems in which it lives; and preventing the herd from spreading into the Kaimanawa Forest Park and the Tongariro National Park. Herd objectives included ensuring that the public was safe from roaming horses, while still allowing and improving public access to the herd and ensuring humane treatment of the horses; reducing conflict between the herd and other ecological values and land uses; and ensuring that the herd is contained to a population that is tolerated by the ecosystems in which they live while still maintaining a minimum effective population that is in general free ranging.

The Department of Conservation has since 1993 carried out annual culls and muster of Kaimanawas to keep the herd population around a target level of 500 horses. The target will be reduced to 300 horses in stages starting in 2009. These horses are either taken directly to slaughter or are placed at holding farms for later slaughter or adoption by private homes. A main reason for the strict population control is to protect the habitat in which they live. This habitat includes 16 plant species listed as endangered, which the Kaimanawa may endanger further through trampling and overgrazing. These plants include herbs, grasses, sedges, flowers and mistletoes; among these are Deschampsia caespitosa (a very rare tussock grass), Peraxilla tetrapetala (a vulnerable mistletoe) and Libertia peregrinans (a possibly locally extinct sand iris). The 2009 culling of the population removed 230 horses from the herd, the largest culling since the beginning of the program, with homes found for 85% of the horses removed. Conservation of these horses is an important matter to the public, and between 1990 and 2003 the New Zealand Minister for Conservation received more public comments on the Kaimanawa horse than on any other subject. In this period, more than 1,400 requests for information and letters were received, with public interest peaking in 1996 and 1997. This was due to a program of population reduction by shooting scheduled to begin implementation in 1996; due to public opposition the shooting was cancelled and a large scale muster and adoption program began in 1997. In 1997, around 1,069 horses were removed from the range and adopted, reducing the main herd to around 500, and reducing their range to around 25,000 ha from around 70,000. Since 1993, a total of around 2,800 horses have been removed from the range. Only one injury resulting in the death of a horse is known to have occurred.

The United Nations' Food and Agricultural Organization lists the Kaimanawa horses as a herd of special genetic value that can be compared with other groups of feral horses such as New Forest ponies, Assateague ponies, wild Mustangs, and with free-living zebras. Kaimanawas are of special value because of their low rate of interaction with humans. This lack of interaction may result in a herd with more wild and fewer domestic characteristics, which is of special interest to researchers. Between 1994 and 1997, students from Massey University studied a population of around 400 Kaimanawa horses to learn their habits and herd dynamics. A 2000 study found that although sometimes there are more than two stallions in Kaimanawa horse herds, only the two stallions highest in the herd hierarchy mate with the herd females. This differs from other feral horse herds, some of which have only one stallion that mates with mares, while others have several stallions that sire foals.