Some introduced avian ‘pests’

The Friends of Drouin’s Trees is in the middle of its autumn bird surveys for 2024. This might be the time to investigate the history and habits of some of our introduced bird species we call ‘ferals’.

In the mid nineteenth century in Australia and New Zealand acclimatisation societies were established to introduce exotic animals and plants. The much-vaunted Ferdinand von Meuller, Victoria’s first government botanist, was alone responsible for ‘distributing’ thousands of introduced plants and seeds! In its short life of just 11 years from 1861 to 1872, the Victorian Acclimatisation Society played a devastating role in this state’s ecology.

SPARROW

The very cosmopolitan House Sparrow was introduced to Victoria in the late 1860s. This little bird thrives wherever there is human habitation – farms, granaries, school yards, town squares, etc. It is a very sociable and gregarious species. The House Sparrow competes with native birds for food and nesting sites. Many references suggest the sparrow is host to a large number of parasites and diseases.

STARLING

The scientific name Sturnus vulgaris is very appropriate for this boisterous and aggressive introduced bird. Starlings are native to northern Europe where they are a migratory species. Here, they seem to have lost the need to migrate and might perform some seasonal local movements only. Their preference for cavities in buildings and trees for their nesting sites is perhaps their worst feature. Starlings quickly drive away native birds that are hollow-dependent for their breeding regimes. They were introduced in the vain hope of keeping pest insects under control. English starlings were introduced in the eastern states from 1863 onwards.

MYNA

Mynas and starlings are related – they belong to the Sturnidae family. The Common Myna was introduced to Melbourne in circa 1860 to help control caterpillars in market gardens. They were only partly successful and soon spread to other areas as well as being ‘shipped’ to north Queensland to control pests in sugar cane. Mynas seldom occupy places with dense vegetation, preferring open areas of parklands, streets, back yards, etc. In 2000, the Common Myna was listed among 100 of the world’s worst invasive species by the World Conservation Union. A nation-wide survey in Australia in 2005 placed the myna at number one pest – ahead of the Cane Toad, rabbit, feral cat, etc. Like starlings, mynas aggressively defend their territories and nesting sites, driving off native birds.

DOVE

The Spotted Dove was introduced in Melbourne in the 1860’s principally for aesthetic reasons. Their native range is the Indian sub-continent and south-east Asia. Some references suggest the Spotted Dove is not a pest to the degree of others in this list. It is believed to have displaced the native Peaceful Dove in some districts but now itself is considered to be ‘under pressure’ from the native Crested Pigeon which seems to be expanding its range. When they drink they only need to place their bill in water. They sort of inhale the water, using their bill like a straw. Other birds need to lift their heads after they take a drink so they can swallow water, but not doves and pigeons.

BLACKBIRD

Pioneers to Victoria found the birdsong of the native species unfamiliar and alien. Wealthy early settlers regarded blackbirds to be a worthy addition to their European-style gardens, principally for their song. The bird quickly spread throughout the state. Even today it is pretty much the most abundant bird in Melbourne and although mainly found in urban areas it is not unusual to see blackbirds in native bushland settings these days. The Common Blackbird is thought to be the principal vector for the spread of the invasive species Sweet Pittosporum.

GOLDFINCH

The European Goldfinch is a small bird in the finch family that is native to Europe, North Africa, and western and central Asia. In Victoria it was introduced in several locations in the late nineteenth century. Apparently, many of these introductions failed, but now the bird is well established, particularly in ‘wasteland’ areas on urban edges. Overseas, the bird is often called the Thistle Bird because of its preference for the seeds of the thistle plant. Goldfinches like to line their nests with mosses, lichens and plant down from thistles.

Leafy streets mean higher house prices

In 2022, Architecture and Design Australia reported that, “Australian homes are among the largest in the world” and that the trend is for them to become bigger! Our units are the largest in the world too.

Data from the Australian Bureau of Statistics shows that house block sizes have been diminishing since 2012. Seldom is there room for a canopy tree in the back or front yard. Yet garden or street trees can do more than just provide shade, lower energy costs and provide health benefits for the residents. Research shows that they can improve a home’s value by tens of thousands of dollars.

A study by the independent advisory body Infrastructure Victoria concluded that property prices for equivalent homes were inversely proportional to their distance from some parkland. Infrastructure Victoria found that this relationship was strongest in regional areas and could produce a difference in house price by as much as $86,000. Interestingly, they found that the effect of a property being near a shopping district has a positive effect on house prices in the country and a negative effect in the city.

The Age, as recently as a few weeks ago, reported that the Victorian Planning Authority has proposed changing the state’s housing code for new suburban estates to encourage developers to include a “deep soil zone” of at least 2.5 square metres for a canopy tree on new properties of less than 300 square metres. Just this last weekend, an article in The Age suggested that Victoria can no longer call itself the ‘Garden State’.

As long ago as 2017, AECOM, a multinational infrastructure consulting firm produced a report Green Infrastructure – a vital step to brilliant Australian cities, in which they state that in the Sydney suburb of Annandale, the average increase in the value of land resulting from a 10% increase in tree canopy was $332 …. per square metre!

A report in the digital property portal, Domain, concludes “… home buyers were prepared to pay a significant premium to live in a leafy street and that premium was up to 3 per cent.”

Lendi, a prominent Australian online home loan platform: “Not only has it been proven that natural surroundings can lead to positive health benefits, but it has also been linked to reduced crime rates, increased property prices, and a welcome drop in temperatures for warmer suburbs.”

Putting your house on the market? Plant a tree!

Drouin’s favourite eucalypt

The voting for Drouin’s favourite eucalypt has concluded and the winner is … trumpet fanfare …

The Old Swimming Hole Giant in Lampard Rd, a magnificent Strzelecki Gum that measures 4.5m in trunk girth, about 30m tall and a canopy spread of 20m. This tree is estimated to be around 170 years old.

Many shires consider their trees as shire assets and apply a formula to their trees to determine a monetary value. Conservatively applying this formula to the Old Swimming Hole Giant gives a value of around $300,000!

The Strzelecki Gum, Eucalyptus strzeleckii, named after the early Gippsland explorer Paul Strzelecki, is a straight growing tree with bark variously described as mottled cream, yellow, white, pink, brown and even green. It can appear to be any or all of those colours at various times of the season.

The best strzeleckis tend to be found growing in fertile soils in places where their roots will get some occassional inundation. Their mature  leaves often have wavy edges and contain numerous oils glands – visible when held up to the light. Young leaves on new growth will often have a waxy appearance – the tree is sometimes called a Wax Tip.

At the bottom end of Lampard Rd, Ezra Cook, an early settler, selected 100 acres in 1878. This old giant would have been part of the landscape and quite a sizeable tree even then. On Ezra Cook’s land there was a fresh water pool fed by a spring and surrounded by beautiful bush with tree ferns. In about 1910 a formal swimming pool was constructed around the pool with steps going down. Many locals frequented the pool and it became well known as the ‘Swimming Hole’ of Drouin.

Due to its very limited distribution of small patches within West and South Gippsland, Eucalyptus strzeleckii is a species classified as "vulnerable" under the Australian Government Environment Protection and Biodiversity Conservation Act 1999 and as "threatened" under the Victorian Government Flora and Fauna Guarantee Act 1988.

Impressive, valuable and certainly worth protecting. A deserved winner.