Should we cull one species to save another?

Nobody has mentioned the cane toad yet. Unfortunately, eradication programmes haven't had the desired impact.

 

Cane toads are almost designed for colonising new areas, they are poisonous in every stage except a small period when its changing from tadpole to toad and, even its eggs are toxic and they lay a lot of eggs.

 

Several years ago, I watched a programme that stated that the red fox was introduced to Tasmania in 2000. As the fox had caused devastation in Australia, I think the people who introduced it to Tasmania were irresponsible and couldn't claim that they didn't know what would happen. At about the same time, the UK government was debating the abolition of fox hunting.

 

An interesting question indeed. A lot of nature management is focussed on "restoring" a certain ecosystem to what is was 100, or 200 years ago, for example by culling certain species. We decide on paper what the ecosystem should be and which species should live in it, thereby excluding any other system or species assemblage from developing. This approach costs a lot of money, is extremely rigid in a rapidly changing world and is prone to shifting baseline syndrome. And just as important: if maintaining an ecosystem requires large-scale human input, is it still natural? Shouldn't we let nature take its course more often?

 

Fortunately there does not appear to be any foxes in Tasmania currently. Some people claim there were never any foxes but personally I think there probably where but they died out within a few years.

 

That is good to know - as we had been told that there is much public opposition to the culling of cats, for example.

 

I couldn't agree more , well said.

 

Wow, I never knew that the koala was an invasive species in some parts, you learn something new everyday.

Do you think the koala thing was due to the charisma effect ?

Personally I find that the "charisma" (or perceived cuddliness) of an invasive plus it being a mammal are enough to make many people oppose its culling.

 

In eastern North America, the populations of White-tailed Deer have exploded beyond reasonable numbers. The entire state of New Jersey, for instance, has 114 deer per square mile! These deer have basically eaten away the understory, shrub, and herbaceous layer of every forest, reducing the forest productivity by 50% and causing harp declines in the populations of many small mammals, plants, and birds. If deer aren't culled, there just simply isn't going to be much wildlife in the area in many cases. Unfortunately, the animal rights people have a very powerful influence over these issues and in many cases stop deer culls pretty much as soon as they are suggested.

In my home state, things aren't quite as bad as the east coast (largely due to the presence of wolves in the northern half of Wisconsin), but in many areas of the state (especially the central and southeast parts of the state) deer can get pretty bad. There has been talk about raising the number that can be harvested during hunting season for many years now, but every time it gets raised HUNTERS oppose it! They apparently like the massive numbers of deer in those areas and want the deer numbers to increase! Meanwhile they now allow the hunting of elk (wapiti) in Wisconsin, even though there are only ~500 individuals in the entire state!

 

When I saw the title of this thread I thought there was something I recently read that I could contribute that would be of interest to others. Then I read the article. And then I read the other posts in this thread, and I realised there are a few other things I could contribute to clarify a few misconceptions.

Firstly, anyone interested in reading more on the subject may find the following of interest:

In 2017 the Royal Zoological Society of New South Wales (RZS) held a one day symposium titled "Killing for Conservation" where a number of scientists either gave spoken presentations or presented posters on the subject. Topics included both philosophical discussions (which included animal welfare and humane issues), ongoing projects discussing the removal or killing of protected native species for the benefit of another more threatened species, and even a new device for the euthanasia in the field for small mammals. Species discussed include dogs & foxes, native parrots, introduced Koi carp, kangaroos, rabbits and the threatened Masked Owl. The proceedings of this forum, including the four plenary sessions, were published as Volume 40 (1) of the RZS publication Australian Zoologist, seen here, and can be purchased from the Society by interested individuals.

The Guardian article is quite a good article. Mattaki suggested in an earlier post that "The fact this is a debate is ridiculous! ". But it's not actually a debate. The baiting is going ahead as planned, regardless of the views of Animal Aid. I suspect that Animal Aid got their knickers in a twist because the RSPB didn't listen to them (although Animal Aid may not have even contacted them) and either contacted news services directly or put out a press release condemning the RSPB action. Either way, the Guardian picked it up. The journalist did what good journalists do - he researched both sides of the argument and put forward a balanced and unbiased article that illustrates both views, and permits the reader to make up their own mind.

It's worth pointing out that there are ethics committees for all programs like this, and the idea is to minimise pain and suffering to the target species, and a number of factors such as efficacy, cost and benefits are all weighed up before the projects are given the go-ahead. Broudifacoum is widely used in these situations for rodents, and if there was something better available it would be used, but there isn't at this point in time.

As for the discussions about Australia:
Feral cats - it appears to me that most people in Australia now accept that feral cats are a significant threat to Australian wildlife, but there is still a minority who don't want to see cats culled (probably for similar reasons to Animal Aid - the welfare of the cats are important, let nature take it's course and conservation concerns be damned). As said previously, this is a minority but how minor I'm not too sure. There is still a great majority of cat owners who recognise the threats posed by feral cats but steadfastly refuse to believe that their pet cat needs to be locked up at night because they are convinced it does not kill native wildlife.

Horses - there are estimates to be 25,000 feral horses in the Kosciuszko/Alpine National Park across New South Wales and Victoria. They are damaging a fragile alpine ecosystem, already impacted by bushfires earlier this year, and the Victorian Parks service planning a cull have been taken to court for an injunction (which was rejected). There has been significant outcry from the public concerning the cull. Those horses in NSW are protected by law because of the romantic views of politicians who see them as a part of our heritage (which, admittedly, they are, but is irrelevant in this case IMHO).

Koalas on Kangaroo Island - there should be some perspective here. Koalas were introduced to Kangaroo Island (KI) in the 1920's - not for tourism purposes as someone claimed in an earlier post, but because koala populations in the South-east of South Australia were declining. That mainland population eventually went extinct while those on KI rapidly built up in numbers. And as a result of it's isolation this population is free of chlamydia, a disease widespread on the mainland.
As for defence forces saving injured koalas, it wasn't 'only' koalas - they also saved injured kangaroos and possums - but that wasn't reported because koalas are a more popular species for the press to report on. Koalas are relatively slower-moving than other animals, like kangaroos and wallabies which could easily outrun a fire-front, and so there were probably more koalas injured by the fires and the greater number may have also contributed to the media attention.

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