Vermin scourge decimates 450,000 tonnes of cane

On November 29, 50 growers from across the Herbert and Mossman districts attended a rat management meeting at Ingham, raising their concerns about this season's cane damage and hearing about the industry's plans to tackle the rat issue.

Canegrowers Herbert River chairman Chris Bosworth said an emergency permit had been granted to allow the use of Liddles Air Service helicopters and drones to spread rat bait in affected areas.

"We already have in place ground based gear, tractors...that's already available to growers, so it was mainly this permit so we could get larger areas done predominately with a helicopter," Mr Bosworth said.

"Cane Growers Brisbane applied for (that permit) with the backing of Herbert Cane Productivity Services Limited and Sugar Research Australia...it was a collaborative effort.

"We're not allowed to do the whole district at once, but we can do (the 26) sub districts...(growers) have to approach HCPSL and they'll be happy to collate the areas and give the farm maps to the operator of the helicopter."

Satchels containing RATOFF bait will be dispersed from the helicopter at one kilo per hectare.

The aerial baiting will be a welcome relief to an industry that suffered a loss of 431,000 tonnes of cane this season - as per a HCPSL grower survey.

"The district has lost about $36m. The miller lost the first four units as well," Mr Bosworth said.

"The cane we then cut that was rat-affected; we also lost Commercial Cane Sugar as well. There were other further losses - the CCS would have been lower in the cane we cut."

Stood over cane and a mild wet season equalled rising rat numbers, according to Mr Bosworth.

"The wet season generally controls the rat numbers because a lot die in the flooded...sump areas...(but) we had a mild wet and the stand over let the rat numbers build up to what we have," he said.

"(There were 5000ha of cane) stood over last year, it's been a food source...so rat numbers expanded.

"We lost 450,000 tonne. We thought because we had a pretty good yield and didn't get to cut that last year. There was an issue with mill performance but we lost 38 days to wet weather also...it wasn't all one-sided.

"The message I'd like to get out there is that growers need to bait and take up this option."

Sugar Research Australia district manager Phil Patane said the trial work being undertaken to make bait more "palatable" to rats, was an industry-wide collaborative effort bringing in experts and industry insiders from SRA, Herbert Cane Productivity Services, the grower collective, and Queensland Canegrowers.

"What we've identified is we've got a significant increase (of rats) in the Herbert region...which is affecting ratoon cane now," Mr Patane said.

"Last year we had an increase as well that contributed also to the increase in standover cane too, whereas this year there is no standover cane but there's still a large population of rats, especially ground rats.

"SRA was tasked to assess the uptake of RATOFF, a standard sachet which we apply in sugarcane fields."

Mr Patane said SRA is working with Animal Control Technologies Australia to roll out five different trials using different attractants on the sachets.

"Some smelt sweet, some didn't, but the results are very positive," he said.

The fifth and final trial is expected to be completed by December 15.

"Then, with those results, Animal Control Technologies Australia will go from there."

Glen Park of SRA is running the trial and has identified 40 active holes in the Herbert region using cement powder around suspected active holes to detect rat footprints.

"He then puts the five sachets with the different attractants on them around the hole in a randomised order, then he assesses them after day one to see if the bait has been opened, moved or taken away," Mr Patane said.

"Then he'll go back and assess again after day four...they'll do their due diligence to get it on the market.

Mr Patane said cameras had also been set up at the holes to ensure the sachets do not impact on non-target species.