By Harry Brook
Do you have a problem with gophers (a.k.a. Richardson’s ground squirrels)? There is no better time than now to prepare to do battle with these destructive rodents. Every one you get now means a lot fewer progeny in the summer.
As they emerge prior to any greening of the grass, this is the time they will eat poisoned baits. Waiting until summer is relatively pointless as the gophers will prefer to eat green grasses rather than poisoned bait. So, the period of time poison bait is effective is relatively short. It will only be consumed until grass green-up. Therefore, to get the best result, it should only be used until mid-May, at the latest.
Males first emerge from their winter hibernation in late February to early March, with females emerging in the middle of March. You basically have a two-month window to effectively control gophers with strychnine bait for about 2 months. Also use fresh bait. Research shows gophers will mostly consume poisoned bait within 24 hours of placing it.
There are a number of baiting strategies out there for gopher control but the preferred one by agricultural producers is using strychnine-coated grain, usually oats. Part of the issue with strychnine is that gophers are also an essential part of the diet of several bird species. The ferruginous hawk feeds its young almost entirely gophers. Scavengers such as crows, ravens and coyotes also eat them. This is a problem if poisoned gophers are left lying in the field. When using strychnine bait, put it well down the burrow entrance to prevent non-target poisonings. Pre-baiting is a way to increase bait uptake and effectiveness. A few days before using the poison bait, put non-poisoned grain down the holes. That should improve intake when the strychnine-coated bait is used.
I mention all this about gophers as there is limited time remaining to use strychnine. Due to COVID-19, there have been supply problems getting the basic ingredients to the manufacturer. This is coupled with a deadline of March 4, 2021 for the manufacturer selling it to counties. This has resulted in a backlog of strychnine orders from the resellers where orders have not been filled and now will not be filled. Unless the federal government grants an extension, due to COVID delays, there will be no more strychnine available to sell, other than what the counties currently have on hand.
Part of the expiring registration for strychnine also means that there is exactly one year from March 4, 2021 for retailers to sell strychnine to agricultural producers. On March 4, 2022, there will be no more sales of strychnine. The expiry of registration also means producers will be allowed to use strychnine, they have in their possession, until March 4, 2023. That makes this spring and next spring the last, best times to control gophers with strychnine. After that it is onto plan “B”.
Alternative strategies for gopher control are not as convenient or easy. Phostoxin or gastoxin pellets, used for stored grain pests, are also registered for use to control gophers. However, you must have a current Farmer Pesticide Certificate and the appropriate endorsement to use them. Use them late in the day, as gophers need to be in their burrows for some time to be effective. There are other poison baits but they are neither as easy and require special care to be effective.
There are several other strategies out there that can work. These include using carbon monoxide from a running motor, an asphyxiating foam, and the use of structures to encourage natural predators to locate near the problem. Biological control can also involve weasels, skunks and badgers.
It isn’t easy to keep control of Richardson’s ground squirrels and they have been a pest for as long as the prairies have been farmed. Know what options are available to you and pick the best ones to meet the goals. We will never eradicate gophers but, with diligence, and a variety of measures, we can keep them under control.
For more information, watch the following videos below.