The Department of Primary Industries and Regions (PIRSA) has completed its assessment of a potential locust outbreak in South Australia’s Riverland area, following the sighting of swarms in late April.
It has been over 15 years since the last outbreak occurred in South Australia, which resulted in a financial impact exceeding $12 million for the state government back in 2010.
Experts caution that the likelihood of an outbreak remains uncertain until spring, but there is a sense of hope that El Niño weather patterns will help keep locust populations under control.
While specialists have characterized a locust outbreak later this year as “unlikely,” they have not entirely dismissed the possibility.
The Bureau of Meteorology (BOM) has predicted an El Niño event, which could lead to hotter and drier conditions during the winter months.
Bertie Hennecke, the Australian plague locust commissioner, noted that the timing of the season suggests an outbreak is “unlikely.”
The swarms that recently appeared in South Australia’s Riverland region migrated from western New South Wales at the end of April as part of a natural migration process.
Dr. Hennecke explained that occurrences like the recent swarm are relatively common, especially following significant rainfall in the Riverland after prolonged dry spells.
“The locust population will begin to increase as they prepare to lay eggs in spring when the locust season commences,” Dr. Hennecke stated. “Locust eggs require soil moisture for survival, so if the soil dries out, an outbreak is unlikely to follow.”
Despite some optimism, officials caution that the Riverland region is not entirely out of danger.
The recent swarms have prompted PIRSA to take action, with teams conducting their first locust survey in the Riverland since 2010.
“The current numbers do not indicate a significant risk,” said Michael McManus, PIRSA’s plague locust commissioner. “If locusts do arrive in the spring, we will be prepared.”
PIRSA is also monitoring other regions in South Australia, particularly in the Mid North and southern Flinders, where favorable breeding conditions could increase the likelihood of an outbreak.
“It is quite rare to find large locust populations in the Riverland,” Mr. McManus remarked. “We typically see them more frequently in the southern Flinders and Mid North regions. With plenty of green feed available this season, if locusts lay their eggs there, we may face challenges in spring.”
Residents in the Mid North, Riverland, and Flinders are eager to avoid a recurrence of the 2010 outbreak, which devastated crops, caused extensive property damage, and cost the South Australian government over $12 million.
Riverland farmer Andrew Biele recalls the severe impact of the last outbreak but is not anticipating a similar situation this time. “The number of locusts we observed this time is far less than what we faced before,” he noted.
If an outbreak does occur, Mr. Biele expressed confidence that PIRSA would be better equipped to handle the situation. “We learned valuable lessons from 2010, and PIRSA has responded swiftly this time around,” he added. “However, it remains another challenge and an added expense that further squeezes our already tight profit margins.”
Dr. Hennecke acknowledged the importance of being prepared but emphasized that locust migration events are a normal occurrence. “We experienced a similar situation around two years ago, but the rainfall and healthy vegetation diminished over winter, leading to a population decline,” he explained.
Even with extensive experience, both experts and farmers recognize the uncertainty surrounding a possible outbreak this spring. “Right now, it’s a waiting game,” Mr. McManus stated. “More data will help us determine if an outbreak is on the horizon,” Dr. Hennecke added.
Back on the farm, Mr. Biele maintains a hopeful outlook for the upcoming season, despite the presence of locusts. “When we see locusts, it indicates that good things are ahead. While good crops grow, so too do the challenges,” he remarked.
