Steve
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The Bilby

There were two types of “Bilby”.  The “Lesser Bilby”, Macrotis leucura”, is officially extinct; the last living ones to be seen being in 1950.  The last specimen recorded was a skull in the nest of a Wedge Tailed Eagle in 1967.  The lesser Bilby was more carnivorous than its relatives, and was more difficult to handle.  The only surviving species is the “Greater Bilby”, “Macrotis lagotis”.  This is now referred to as “The Bilby” or “The Rabbit Eared Bandicoot”.  All references to the "Bilby'" in the rest of this article are to the Greater Bilby.

The Bilby is a type of Bandicoot.  The have bigger ears and a longer tail than the other species of Bandicoot. 

Size

Bilbies vary, but are similar in size to a wild Rabbit, or very small cat.  The males are bigger than the females.  In the wild, an adult female will normally be between 800 grams and 1.1 Kilograms while a male will range between 1 and 2.5 Kilogram’s.  A well fed male Bilby in captivity can grow to over 3 Kilograms in weight.

Diet
 
Like the other Bandicoots the Bilbies are omnivores. They eat insects like termites, honey ants, grass hoppers, locusts, and beetles.  They also eat arachnids including spiders, and small vertebrate animals.  The plant part of their diet includes fruit, fungi and seeds including grass seeds as well as bulbs, including the bush onion (Cyperus bulbosa), tubers and other roots. 
They will dig down about a foot (30 centimetres) to find food. Although there is a certain amount of competition between Bilbies and Rabbits for food, this competition is often exaggerated and is probably not a major factor in the decline of the greater Bilby and the extinction of the Lesser Bilby.
Much of the food the Bilbies eat is underground.  They use their long thin tongues to get things like bulbs.  This often means that they are also eating a lot of sand.
 
Senses
 
The Bilby has excellent hearing; its large ears presumable help with this.  A Bilby's ears are very mobile and can be moved in several directions, or folded against its body.  The ears  also help the animal get rid of eccess heat.
The Bilby's long nose also provides it wth a excellent sense of smell.
Bilby eyesight is poor.

Burrowing

Bilbies dig well with their powerful front legs.  They often dig about 12 borrows in their home range. They also dig near the surface to get their insects and other food. In the past when bilbies were common over about 70% of the Australian mainland, their burrowing was an important factor in the aeration of the soil and the burying of organic matter.

A Bilby burrow will typically be 3 metres (10 feet) long and 2 metres deep. They are deep enough for the Bilby to avoid the extreme heat of the Australian outback in the summer, or to survive if a bushfire goes over the top.  The burrows spiral downwards, making it more difficult for predators to go down.  The Bilby also back fills part of the burrow when it is down which  helps to stop predators.

The introduction of hard footed grazing animals including cattle, Sheep and Goats not only devastated the Bilbies’ natural habitat, but also these animals destroyed many of the Bilbies’ borrows.  The valuable aeration and mixing of the soil that used to occur no longer does with the extreme rarity of Bilbies.

Compatible with Humans?

Potentially the Bilby is compatible with Humans.  They would be an asset in some  types of garden, eating various pests. The Humans would have to be a little tolerant of the animal making burrows in inconvenient places, and eating things the people wanted to eat.

However, this is an almost completely hypothetical situation.  Although this animal might be compatible with us if it had been given the chance, instead, we imported domestic and wild animals that are definitely not compatible with Bilbies.

Range

Before Europeans came to Australia, the Bilby had an extensive range, including about 70 percent of the Australian mainland.  Now they are confined to a few areas which are too harsh for our introduced animals.  Although they were adaptable enough to colonise a huge range of habitats they are now in danger of extinction.

Decline
 
There are several reasons why the Bilby declined so much.  One of them is hunting.  Before Europeans came the Bilby was hunted, but not in sufficient numbers to seriously reduce its numbers.  Europeans hunted it for its beautiful fur.  Bilbies were also posioned in huge numbers.  The poison was not generally aimed at  Bilbies, but was intended for Rabbits.  The Bilbies were wiped out, but plenty of Rabbits survived.
Tghe introduction of Foxes was a major factor in the partial extinction of Bilbies.  This was made worse by the destruction of Bilby habitat and burrows by hard footed grazing animals.
 
Habitat
 
It is sometimes said that the Bilby is a creature of the Arid regions of Australia.  This is true now in the sense that it is only in these regions that it is surviving, except in a few places where it is protected by fences from introduced predators.  Before Europeans came to Australia its range including some wetter habitats, including areas now settled in South Australia.  Potentially Bilbies could be reintroduced to these areas.
 

Competition with Rabbits

Competition with Rabbits and other introduced animals for food is often given as one of the reasons for the Bilbies disappearance.  Personally I seriously doubt this.  The overlap between the diets of Rabbits and Bilbies does not seem to be enough to make them totally incompatible.

Predators

Native Predators

Before there were any animals introduced by humans in Australia, the native predators of the bilby would have included Goannas, Quolls, Tasmanian Devils, Thylacines, Wedge Tailed Eagles and other birds of prey.

Introduced Predators

The Bilby is now preyed on by Dingos and other Dogs which were introduced as domestic animals and have now gone feral.  But much more important predators are Foxes which were introduced for recreational hunting so the upper class English could dress up in fancy clothes and ride around the countryside with a pack of specially bred dogs to tear the Foxes to pieces.  This is now illegal in Australia and some other countries.  I believe it has actually been banned even in England although there is a movement to bring it back.

It is sometimes claimed that the Fox was introduced in an attempt to control rabbit numbers.  This in incorrect; the Fox was introduced before the wild Rabbit.  Also, Australia did have excellent Rabbit predators.  Rabbits are a major part of the diet of the Wedge-tailed Eagle, but millions of these were deliberately killed.  Goannas also eat Rabbits, but their numbers have been drastically reduced.

Another predator of the Bilby is the cat which was introduced as a pet and  not only allowed to become feral, but has also been deliberately introduced to the Australian bush.

In areas where Dingos are present in significant numbers, the Bilbies tend to do better than if no Dingoes are present.  The Dingos would certainly eat some bilbies, but they also tend to reduce the numbers of both Foxes and Cats.

The English were not content to adjust to Australia, but wanted to turn it into something like England.

Breeding
 
The Bilby is a marsupial.  Its gestation period is only about 14 days.  After birth the babies crawl to the mother's backward facing pouch and locate one to their mother's eight nipples.  The babies stay in the pouch for about 75 days.  After that they spend another 14 days or so in a nursery borrow with the mother returning frequently to feed them.  The mother can have from 1 to 3 in a litter and can have up to 4 litters a year.  They can breed any time of the year.  The Bilbies can breed at 6 month old.  They are a fast breeding animal.

The Easter Bilby

I described the Bilby as being iconic.  At Easter it is traditional in many countries for the Easter Bunny to be one of the symbols of Easter.  Rabbits and eggs are both used at Easter as symbols of fertility. Some Christians object to the commercialisation of Easter and Christmas.  I apologise if anything I say causes offence.

In Australia, there is a movement to replace the Easter Bunny with the Easter Bilby. You can buy Chocolate Bilbies as well as Chocolate Rabbits here.  Apart from raising peoples' awareness of this threatened animal the Darrel Lea company has donated substantial amounts of money from the sale of their chocolate bilbies for Bilby conservation. With their fast rate of breeding, the Bilby is certaily an animal worthy of being a symbol of fertility.

Bilbies as Pets?
 
The Bilby is in danger of extintion, so of course it should not be kept as a pet.  It is also illegal in many places to do this.  However, the occasional remark to the effect that there are were no Australian native animals suitable to be kept as pets needs to be severely dubunked.
If the Europeans had not driven this animal to the edge of extinction, it would have made a suitable pet for some people in certain situations.  No pet is going to suit everyone in every situation.  The Bilby would have some similarities to a Rabbit as a pet.  Both animals are potentially vulnerable to predation by Dogs and Cats, and both can burrow.  The Bilby has the advantage of not being suseptible to the horrible diseases that have been introduced to control Rabbits.
The life span of the Bilby is about 10 years in captivity so it will live a little longer than most Rabbits. 

Conservation Status

The bilby is listed as Vulnerable in Australia as a species, but Extinct in South Australia and Endangered in Queensland.

Can the Bilby be Saved?

Yes, of course it can. We will need to be serious about saving this Iconic animal.  It is now a protected species all over Australia, and very active steps are being taken to reintroduce it to its former range.

Reintroduction to South Australia

In 1994, a long term three stage project was started to bring back the Bilby.

First Stage

A captive breeding program was started at Monarto.  This was successful.

Second Stage

Bilbies were reintroduced to an island in Spencer Gulf.  This island had no Foxes, Cats or Rabbits.  It was also not being used for grazing now.  The bilbies were very carefully released.  There were firstly given a small, fenced area with food so they could dig their first burrow.  Then they were allowed into a bigger fenced area for a while until they were let out into the rest of the island.

At all stages they were given some food so they could adjust to finding their own food gradually.

Despite some setbacks, the Bilbies are doing reasonably well on the Island.

Third Stage

The next Stage is to catch some of the wild Bilbies on the island and release them in carefully selected sites on the mainland.

This is where more problems may arise.  We have changed the environment so much that they will still have the problems that caused their local extinction in the first place.

Our Attitudes

Attitudes are starting to change.  The use of the Bilby as a symbol of Easter is a small part of this.

A bigger part is the recognition by ordinary Australians of the importance of the Environment.  It is a pity that our governments are so far behind the common people.

However, the internet is starting to empower us.  The Power of the People is Paramount. The Internet gives us both a way of finding out about things, and a way of expressing our opinions.  I abhor the idea of Internet Censorship.

Australians are starting to reject the governments’ (both State and Federal) idea that increasing the population indefinitely is a good idea.

 

Sources

http://www.derm.qld.gov.au/wildlife-ecosystems/wildlife/threatened_plants_and_animals/endangered/bilby/

http://www.easterbilby.com.au/Project_material/factsheet.asp

http://members.optusnet.com.au/bilbies/Bilby_Society_Fact_Sheet.pdf

http://www.nt.gov.au/nreta/wildlife/animals/threatened/pdf/mammals/greater_bilby_vu.pdf

http://www.environment.gov.au/biodiversity/threatened/publications/bilby.html

www.wwf.org.au/publications/greater-bilby-fact-sheet.pdf

http://www.wpsa.org.au/pdf/bilby/WPSAProject_Bilby.pdf

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Greater Bilby            Lesser Bilby

Pictures by John Gould, 1863
"Mammals of Australia", Vol. I
 
A Bilby at Sydney Wildlife World
 
Bilby at Monarto Zoo April 2008
Photo by stephentrepreneur from Adelaide, Australia (I Shot the Easter Bilby!  Uploaded by Giggy) [CC-BY-SA-2.0 (www.creativecommons.org/licenses/by-sa/2.0)], via Wikimedia Commons.
This file is licensed under the Creative Commons Attribution-Share Alike 2.0 Generic license.
 
Macrotis lagotis by John Gould, 1863
"Mammals of Australia", Vol. I Plate 7

Current Range of the Bilby

By Nrg800 (Own work) [CC-BY-SA-3.0 (www.creativecommons.org/licenses/by-sa/3.0) or GFDL (www.gnu.org/copyleft/fdl.html)], via Wikimedia Commons
 
Spinifex Grasslands in the MacDonnell ranges of South Australia.  There are probably no Bilbies in the area shown in the picture, but they will live in this sort of country.
By Thomas Schoch [CC-BY-SA-2.5 (www.creativecommons.org/licenses/by-sa/2.5)], via Wikimedia Commons
 
Dingo at Australia Zoo
 
Although Dingos are predators of Bilbies, they also help to control Foxes and Cats which are much worse predators of Bilbies.
 
The introduction of the European Red Fox for recreational hunting was a major blow to Bilbies and other Australian animals.