Gopher heads are popping out of holes across the Prairies but two rodent experts say it is unlikely farmers will face a Caddyshack-sized problem in 2005.
“There is a residual population still there that needs to be dealt with but I don’t think we’re looking at the same population and the same intensity of the damage that we were seeing two or three years ago,” said John Bourne, vertebrate pest specialist with Alberta Agriculture.
While it is difficult to get a handle on any pest residing below the ground, most signs point to manageable levels of the Richardson’s ground squirrel, said Scott Hartley, pest management specialist with Saskatchewan Agriculture.
Read Also
Agriculture ministers agree to AgriStability changes
federal government proposed several months ago to increase the compensation rate from 80 to 90 per cent and double the maximum payment from $3 million to $6 million
Last year the consensus was that with spring flooding, increased predation and control efforts, farmers were able to beat back what had become a serious pest problem during the drought years.
That trend is expected to continue in 2005, said Hartley, although he has already received calls from producers in the province’s southwest reporting serious gopher infestations.
One reason for his optimism is that 2005 will be the second year producers have unimpeded access to a strychnine-based fresh bait product, which appears to be meeting performance expectations.
Alberta research trials conducted last year show the new perishable product had an efficacy rate in the 90 percentile range compared to results in the 60-70 percentile range for the old dry bait product.
But there are some drawbacks associated with the new control. It is expensive, has a limited shelf life and isn’t as convenient to use as the old liquid method.
Farmers used to be able to purchase strychnine concentrate, mix it with liquid and apply it to grain right on the farm. But the Pest Management Regulatory Agency shut down that practice after it discovered the concentrate was killing cats, dogs and wildlife, said Bourne.
In 1992 the agency took the concentrate off the market.
In its place manufacturers were allowed to sell farmers treated grain in the form of dry bait.
“There was a great leap of faith thinking that if it was dry it would perform just as well as if it were wet,” said Bourne.
His research proved that wasn’t the case and paved the way for an emergency use registration of a fresh bait product made with liquid strychnine and distributed through rural municipalities in Saskatchewan and Alberta between 2001 and 2003.
That program has expired but the PMRA has allowed two Canadian manufacturers to continue making the fresh bait product and sell it to farmers.
Strychnine-based products account for 85 percent of gopher controls but there are other emerging options.
“There are other (controls) on the horizon that are closing in on strychnine but they need to be further tested,” said Bourne.
He is particularly excited by the results he got from mixing a registered anticoagulant called Rozol with a taste and smell additive supplied by Edmonton Exterminators.
“With this additive it seems to have great promise,” said Bourne.
Rozol didn’t deliver the same level of control as strychnine products but it was in the acceptable 70-80 percent range. And it would appeal to many farmers because it is a cheaper, safer and more useful way to manage gophers.
Before it can be sold to farmers the two manufacturers have to get together to develop the new product and get it approved by the PMRA.
Bourne said the prairie provinces are also working on developing an integrated pest management strategy for the Richardson’s ground squirrel.
It will explore topics like setting an economic threshold or an acceptable population level for the pest, using crops they despise like castor beans in shelterbelts and attracting natural predators to farms by such things as building aerial platforms for hawks.
There is no set time for releasing the strategy, which is seen as a long-term alternative to controls.
“It will prevent this cycle of population buildup, population crash and all this poison being used,” said Bourne.
