Removing barriers to allow emu migration and seed dispersal for healthy habitats
The emus across the Clarence Valley and Bungawalbin areas are the very last of a species that once roamed across much of the east coast of Australia. Once common, over 200 years the number of emus on the coast has dwindled and they are now rare and endangered with only a small population left on the north coast. The coastal zone of the lower Clarence-Richmond comprises a large, connected, diverse and largely undeveloped corridor that provides the habitat to support the last of the Coastal Emus.
What is the Issue?
Being highly mobile and ranging over a wide area, any barriers restricting emu movement can have a major impact by reducing access to natural food sources, isolating and preventing breeding and nesting, and blocking escape from predators or bushfires.
The emus travel big distances, use a great range of different habitats and have a generalist diet so they are found to use many vegetation types throughout the coastal areas such as dry heath, dry sclerophyll forests, rainforest and wetlands. As they move they are always browsing on fruits, nuts and seeds and studies show they can have up to 1000 seeds in a 100gram scat or dung making them a seed dispersal vector through this landscape – across large distances maintaining the floristic diversity between fragmented remnants of bushland across the coastal corridor. Emus movement is a critical process in maintaining a genetic diversity of plants across large areas, many of which threatened or rare.
Busy roads, thick vegetation such as dense weeds, new residential areas, overgrown tracks and fences are the typical barriers impacting on our emus. Fences in particular prove to be a significant barrier for emus. Individuals and family groups have often been seen walking up and down fence lines for hours looking for a way through.
In some cases they can get trapped on road verges creating a dangerous and deadly situation.
What is happening ?
The solution isn’t as easy as removing all fences and barriers. Fences are used for a reason on farms and rural properties to define boundaries, exclude pests such as pigs, control unwanted human access and manage stock.
Recent trials have been looking into how fences can be removed or modified to provide greater movement for emus – while still achieving the intended purpose of the fence. Many old derelict fencelines could simply be removed especially in areas where evidence of emus such as tracks and feathers on barbed wire is found. Many rural fences can have plain strands of wire incorporated to allow emus and other wildlife to slip under without being tangled or injured.
Several new “emu gateway” designs are attempting to provide emus with a suitable gap to fit through while maintaining the purpose of the fence. In this instance, a simple design has been constructed with two boards across a gap – this allows emus to step through and duck under while restricting unwanted access by humans, trail bikes, horses and other vehicles. This is a low-cost option that can be retro-fitted to existing fences. Other designs are seeking to contain cattle while permitting emus to either squeeze between or step through.
Locating these modified gateways in areas where there’s the greatest chance of emus finding and using them is critical. They are likely to use tracks and walk along fencelines so fence corners and fences at track intersections are possible locations to investigate. Often emus leave feathers on barbed wire fences when they push through and this may assist targeting installation. Off-setting the gateways at 90 degrees to the fenceline will increase the chances of emus finding the opening. Using a guiding fence or hedge to funnel the emus in to the gap may also be useful.
What are we hoping to achieve?
We are working with landholders across the Coastal Emu Corridor to maintain free, unimpeded movement of emus across the landscape. This work needs to expand to new areas to achieve landscape-scale migration and access to resources such as food and nesting sites. In many cases this access has been impeded and action to reinstate seasonal migration corridors and regular movement pathways is required.
Underpinning this important action is the critical need to maintain the ecosystem function that the emu plays in the landscape – consuming fruits, nuts and seeds, and dispersing large quantities of seed in droppings across large distances. It’s likely that the long period of time the seeds sit in the emu gut stimulates germination in some species. This function supports genetic diversity between often fragmented remnants of important ecosystems such as rainforest. With such a high number of Threatened plant species in this landscape, as well as seven Endangered Ecological Communities occurring across the Coastal Emu Corridor, this important ecological role is crucial to maintaining nationally-significant biodiversity values.
We can all contribute to protecting the last of the Coastal Emus. By taking simple action like modifying fences to remove barriers everyone can be part of the solution.
If you would like to get involved, learn more about emu fencing or the Coastal Emu Alliance please Contact Us