Honey Bee Small Animal Pests: Mice, Skunks, Shrews, and Other Minor Pests

Thursday 7 September 2023

We all know that there are a variety of pests and diseases that impact honey bees. Often the first pest species that come to mind are varroa mites, or the devastating bear attacks. We often neglect to think about the small mammals that cause significant damage to honey bee colonies. Today’s blog will discuss why this group of small animals causes issues for beekeepers, and how they can be best managed.

Honey Bee Small Animal Pests: Mice, Skunks, Shrews, and Other Minor Pests

Mice inflict significant physical damage to honey bee hives. They do so by entering the hives in the fall and winter and cause extensive damage to comb and woodenware (Sammataro and Avitabile, 2021; Sarwar, 2016). Mice may feed on various components of the colony including bee bread, honey, brood, and adult bees. Additionally, the droppings and urine of mice can impact honey bee behavior (Sammataro and Avitabile, 2021; Sarwar, 2016). Mouse urine is particularly repellent, and it disrupts cluster behaviour. There are a few things to look for to know if you have mice in your colony, including: chewed comb and/or wood; mouse droppings on the bottom board; holes chewed through entrance reducers to allow mice to enter the hive; and nest material between frames (Sammataro and Avitabile, 2021; Sarwar, 2016). To minimize damage from mice, bees should be placed on stands, use entrance reducers, use metal mouse guards, and keep weeds down around the hives. It is important to note that bees placed near a forest or in fields of tall grasses are at a high risk for mouse damage (Sammataro and Avitabile, 2021; Sarwar, 2016).

Mouse nest in bee hive (Penn State Department of Entomology©)

Skunks are a serious pest of honey bees. They cause damage to both equipment and bees, and they dig up bee yards looking for food (Sammataro and Avitabile, 2021; Sarwar, 2016). Often these animals visit colonies at night, and they force bees out of hives by scratching at the entrances. If these animals repeatedly visit bee yards at night, there can be a significant decline in the adult population of honey bees. These mammals have been known to feed for an hour or more and this feeding activity causes bee colonies to become more defensive and aggressive (Sarwar, 2016). Some signs that skunks are visiting your bee yard include scratch marks and dirt on the hive front, outer covers off or skewed, and weak and/or defensive colonies (Sammataro and Avitabile, 2021; Sarwar, 2016). The best way to help manage this pest is to place bees on hive stands at least 18 inches high, which will keep bees out of reach of small predatory animals. Additionally, when hives are placed higher above the ground skunks must expose their bellies, and being stung on their underside deters them from the hive. Properly set up electric fencing will also protect against skunks.

Shrews are a major pest of honey bees in Atlantic Canada. There are seven species of shrew found in eastern Canada. When it comes to eating honey bees, the Common Shrew is the most likely culprit. Shrews have a very high metabolic rate and, unlike many small mammals, are not dormant or hibernating through the winter months. The result is that these insectivores will almost double their food intake to keep warm and active during winter. For these reasons, beehives must be protected against shrews while the bees are clustered and most vulnerable. It is required to protect honey bees in Atlantic Canada with the use of shrew guards in the winter months.

Other minor honey bee pests in Atlantic Canada include raccoons, squirrels, and rats. These animals cause similar issues to those mentioned above, and they can also be managed by using hive stands, entrance reducers, and electric fencing.

When attempting to manage small mammalian pests there are several things a beekeeper needs to consider. First, the beekeeper needs to be confident about what animal pest they are dealing with. This must be done by studying the signs left by the animal (Sarwar, 2016). Second, the beekeeper needs to consider how much damage might occur without any additional control and what are the benefits of control versus the cost of damage. Essentially a beekeeper needs to determine the economic threshold of the pest (Sarwar, 2016). Next, is the animal legally protected in a way that limits the action the beekeeper would otherwise take. Finally, will there be any impacts on non-target animals if a control program is implemented (Sarwar, 2016).

These small mammalian pests can be a serious concern for beekeepers. If not monitored and managed well, honey bees can be decimated by these pests. However, if honey bee colonies are kept strong and healthy, and you continually monitor and take the necessary steps to minimize damage, you can successfully manage these pest species in your apiary.

Sammataro, D., and Avitabile, A. 2021. A beekeeper’s handbook: fifth edition. Cornell University Press.
Sarwar, M. 2016. Predations on honey bees (Arthropoda) by vertebrate pests (Chordata) and control of nuisance. International Journal of Zoology Studies. 1(2): 12 – 17.

Connecting with ATTTA Specialists

If you’d like to connect with ATTTA specialists or learn more about our program, you can:

visit our website at https://www.perennia.ca/portfolio-items/honey-bees/

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