Pests

Pests

Introduction

The Hedgehog is the nocturnal pest we hear snuffling about under our windows after dark, searching out for slugs and snails. It first arrived in New Zealand when the Canterbury Acclimatization Society received a pair in 1870’s. They were introduced to make European settlers feel more at home in their new land. More Hedgehogs were imported in the 1890’s and from there, they were released throughout New Zealand and expanded and now they are killing our native species, so I have determined that to mitigate the deleterious effects of hedgehogs in New Zealand is by spreading traps throughout the Bay of Plenty.

How did Hedgehogs arrive in New Zealand and why were they introduced?

Hedgehogs first arrived in New Zealand by acclimatization societies, they were an association that introduced non-native animals into various areas around the world, they did this so they hoped that they would adapt to their environment. Hedgehogs were introduced to remind the settlers coming to New Zealand of their homeland. They were introduced to control gardens by eating bugs and so on. Hedgehogs arrived in New Zealand in the 1870s, some hedgehogs were transported to the south island between the years 1906 and 1911 and from there, they have widely spread throughout New Zealand and their population increased at an exponential rate.

What impacts does the hedgehog have on its food web?

Hedgehogs eat a wide variety of insects, fruits, vegetables and they eat endangered species such as endemic giant snails, the weta species, and other invertebrates. Hedgehogs also eat other native slug snails. Big varieties of fruits are another choice among hedgehogs as well as vegetables. However, hedgehogs will sometimes eat meat if there are any leftovers in peoples backyards. Even though Hedgehogs prey on endangered species, these little critters get preyed on by Wild pigs, dogs, and cats. They also eat other species like lizards, mice, and surprisingly frogs. It is estimated that hedgehogs can eat over 160g of invertebrates everyday. As well as eating native baby birds, they can apparently also eat adult birds.

How are hedgehogs considered a pest?

Hedgehogs are all over New Zealand, and pose a big threat to many of New Zealand's native species. Hedgehogs have been classified as pests due to the nature of their behavior and impact on our native taonga as well as their destructive behavior. Hedgehogs have been found to eat eggs of riverbed birds such as banded dotterel and black-fronted terns. Hedgehogs also prey on native slug, snail, and terrestrial insect populations because they have an appetite for invertebrates. Hedgehogs are cute and clever but they have a good sense of smell which allows them to smell for food.

Where can Hedgehogs be found in New Zealand?

Hedgehogs can be found all over New Zealand but they can be found in lowland habitats and you can find their homes among hedgerows and can be found under shrubs in your gardens. Hedgehogs in New Zealand can be found in pretty big numbers on open farmland and in scrubs. In lots of areas in New Zealand, Hedgehogs are estimated to be found every 2 - 4 per hectare and in other areas, there can be as many as 8. Hedgehogs are rarely found in inhospitable environments such as some of the wettest parts in New Zealand and areas with a large amount of snow. They are most commonly found in coastal areas because that's where there are lots of nesting birds around which are easy to get to for the Hedgehog.

What is the behavior of the Hedgehog?

Hedgehogs are normally solitary and like to live by themselves even though mothers are sometimes seen with well developed young. Hedgehogs are nocturnal animals and they prefer going out at night, they are out 2 to 3 hours after sunset and they will go out again between 9 to 8 hours after sunset but if you see one out in the day, they are either looking for water or they are blinded by some sort of parasite and lastly, they are too sick to hibernate. Hedgehogs hibernate in the winter and males come out a month before females do, the length of the hibernation all depends on the climate. In coastal areas, very little hedgehogs hibernate and in the colder regions, almost all of them do and if so they will hibernate under tree roots, in rabbit holes or in any area that is dry.

Does the Hedgehog have any diseases?

Hedgehogs carry many diseases, one of them is Salmonella germs. Salmonella germs can be found in their droppings even though they look healthy and these germs can spread really quickly around their body and any area where they live. They can also get tuberculosis by infected possums that are eating within the hedgehog's home range. Hedgehogs are liable to suffer from several diseases such as cancer, some of which can be avoided and beware of touching a hedgehog or mostly anything in its habitat because you could get sick. There are many signs that a hedgehog is sick, common conditions you can see are sneezing, coughing, panting, a boring expression and even paralysis. They can also suffer from internal and external parasites. Internal parasites are parasites that live inside the intestinal tract and external parasites live on or around the animal. People can actually get sick after a person has touched a hedgehog in their habitats.

How have they not been eradicated yet?

Hedgehogs are all over New Zealand and they pose a big threat to our native species. Since the 1950s, the number of hedgehogs have started falling but in the larger parts of NZ, Hedgehogs are still more numerous than Britain. Hedgehogs produce babies between the dates april and september and they can have up to 4 - 7 babies once a year but they have a high death rate because the babies are left on their own for 7 weeks. People are trying to eradicate hedgehogs and there are many ways to do so such as Traps, hunting, poison and running them over. Hunting has many cons such as having to buy ammo for it and hedgehogs could be harder to hit since they are small targets but they move quite slow and it does not achieve significant conservation benefits, you can not target rats or mustelids (weasels, stoats and ferrets) so you might have to do it illegally. But on the other hand, using poison is effective, It can be used on food for bait and through the air. Let's say we use Aerial control, it targets a greater number of pests than trapping or hunting and a wider area can be covered by air than what can be covered on foot but some non-targeted species can be poisoned from the toxins and there is an expense involved although it is a cheaper method than ground control. Using traps is a good method of pest control. The types of traps that can kill are DOC 150, DOC 200, these traps can be used for different animals such as rats and stoats. Another trap which can be used is box rat traps, The DOC 200 has a large type of jaw which is released if pressure is put on the plate where the food is placed and the DOC 150 is quite the same as the DOC 150 but it is quiet smaller and a spring is used to make the jaw slam shut but I would choose DOC 200 for how fast it kills. It is recommended to place these traps near the beginning of the bird's breeding season.

Fertile Question

What should be done to mitigate the deleterious effect of Hedgehogs in the Bay Of Plenty?

The most effective way of eradicating the deleterious effect of Hedgehogs in the B.O.P is by using traps. They can be placed in the bush or in people's backyards, placing them in backyards is a good idea because hedgehogs love to eat vegetation and they dig burrows in the backyard, placing them in the bush catches them off guard thinking there is food but if you place them in the bush, you would have to do a 1 to 2 week to see if you caught a hedgehog. traps are quite cheap and easier than hunting and poisoning. The only downside is that other animals and endangered species could fall for the trap. People don’t consider these little critters as pests due to their cuteness and small size, To convince people hedgehogs are pests can be by learning about in schools and maybe advertising that pest situation on Tv.