Since the introduction of pest species during European settlement there have been devastating impacts on wildlife populations in Australia. Unfortunately, even conservation areas like North Stradbroke Island are still fighting this battle.
Straddie’s water mice, turtles, shorebirds and frogs have all been impacted by the growing number of feral foxes and cats on the island.
As many residents and visitors to Minjerribah are aware, fox numbers have multiplied over the past decades, resulting in significant damage to local wildlife.
Healthy Land and Water have run an effective baiting program on the island since 2017, seeing a reduction in fox numbers over the past few years.
Despite this success, baiting becomes more difficult as the cunning foxes learn to avoid the baits and teach their young to do the same. The next step in the eradication program will be to fumigate fox lairs as well as employing foot traps.
Despite having been in Australia for over a century, foxes still breed on a Northern Hemisphere cycle, which takes place at the time of the summer solstice there. Fumigating lairs works best at the beginning of the mating season (April to June – the Northern winter solstice) and continuing until about November.
The drop in fox numbers is certainly a success story – but when one predator is dethroned another takes its place. In this case, it’s the feral cat.
Feral cats are a huge threat to Australian mammals, travelling long distances on the island to hunt. With trapping efforts, researchers have found they eat a variety of animals including squirrel gliders, bandicoots and various birds.
Feral cats are going to be a challenge to eradicate as they are notoriously hard to control by shooting, trapping and baiting. Surface baiting isn’t a suitable option as it also kills wildlife like birds and marsupials. An alternative is to use both cage traps and foot traps, but they are clever animals and often prefer live kills to scavenging.
Truly feral cats have no relation to domesticated cats, they live wild and hunt. But while domestic cats have no relation to feral cats, they can still have an impact on our local wildlife as many people let their cats roam.
As residents and visitors to Straddie, the best thing concerned citizens can do is make sure their pets are desexed, and keep pets – especially cats – contained at night.
As a national problem, the Australian Government funded the development of an innovative new technology to target cats.
The Felixer Grooming Trap is a robotic grooming trap about the size of a printer. A laser beam recognises the animal, and if it is a cat, the machine administers a single dose of toxic gel to the animal’s coat, which is ingested when the cat grooms itself. The Felixer can differentiate between cats, possums and other animals mainly by their leg and body length, as Australian wild animals generally have short legs and different body shape.
It has been successfully trialled on Kangaroo Island and in the Northern Territory, and once available for general use, it is hoped to be used on North Stradbroke Island.
Minjerribah has long had a problem with cane toads, with damaging impacts on native animal populations. Predators like snakes and goannas are poisoned by cane toad toxins, and native frogs must compete with them for habitat and food.
At Cylinder Beach, the lagoons that fill with stormwater and stagnate have been a prime breeding spot for toads, while Brown Lake is currently suffering a serious infestation. Brown Lake is a hotspot for rare native frogs and other aquatic species, so controlling the growing population of cane toads in these sites of ecological importance is a top priority.
You might unknowingly be providing a haven for cane toads in your backyard. The NSW Department of Environment provides a handy checklist to ensure you aren’t attracting cane toads, and what you can do to deter them.
You’ll also find tips on how to identify cane toads, and how to dispose of them humanely and safety. Even dead toads can poison wildlife.
It’s important to become familiar with our local frog species before participating in cane toad control. As tadpoles they can be indistinguishable from native frog tadpoles, and even as adults they can be confused for large frogs.
For tips on how to identify our local frog species, and how to create a frog friendly backyard check out Moreton Bay Regional Council’s Frog Brochure.
Researchers from the University of Queensland’s Institute for Molecular Bioscience have developed a simple trap to eradicate this invasive and well derided pest.
The traps use a chemical lure that is naturally found in toad eggs, and are set to float in managed waterways, like creeks, dams and ponds. They attract thousands of toxic tadpoles in just a few hours, after which the tadpoles are disposed of in an environmentally sound and humane manner by cooling and freezing.
