Backyard
What to feed cardinals in winter
A Northern Cardinal in January weighs about 45 grams. Research on winter cardinal energetics (Journal of Experimental Biology, 2012) shows he must consume enough calories during daylight hours to fuel the entire night, and his fat stores at dusk are rarely more than what that one night demands. He fluffs his feathers, drops his body temperature slightly, and shivers his way through. He does this every night of his life. He does not migrate. The bird at your December feeder is the same bird that was there in May.
The simple, blunt truth of winter feeding is that a reliable food source can be the difference between him being there in May and him not. A cardinal who finds your feeder in November and then finds it empty in February will not necessarily die, but his odds shift. A cardinal who finds it consistently stocked will breed in your garden in April.
Here is what to put in it.
The one seed that does almost all the work
Black-oil sunflower seed. That is the answer. If you do only one thing right, this is it.
Black-oil sunflower has thinner shells than striped sunflower (cardinals’ bills crack it more easily), more oil per kilo (more calories), and reliably draws every common winter feeder bird without effort. A 10 kg bag from a feed shop is the most efficient single calorie source you can put outside in December.
If you have squirrels and you want to drive them off the feeder, switch to safflower. Cardinals love it. Squirrels mostly do not. Grackles do not. Starlings do not. It is the closest thing to a “cardinal-only” seed.
The second-best move is to add a suet feeder. Pure beef suet, ideally with sunflower hearts pressed in. Fat-dense, calorie-dense, takes the bird through the longest nights.
The full hierarchy of winter foods
| Food | Calories per 100g | Cardinal preference |
|---|---|---|
| Beef suet | ~854 kcal | Eaten readily in cold weather, ignored in summer |
| Black-oil sunflower (in shell) | ~580 kcal | Top choice |
| Sunflower hearts | ~580 kcal | Strong second, faster eaten, more waste-free |
| Safflower | ~520 kcal | Strong choice, excludes squirrels and grackles |
| Peanut hearts (unsalted) | ~570 kcal | Eaten readily |
| Cracked corn | ~360 kcal | Eaten if dropped on the ground, not preferred at the feeder |
| Mealworms (dried) | ~628 kcal | Eaten by females especially. Protein. |
| Milo | ~340 kcal | Cardinal will pick this out of a cheap mix and discard the rest |
| Bread | Variable | Do not |
Cheap “wild bird mix” is mostly milo, wheat and red millet. Cardinals do not want any of these. The bird picks out the few sunflower seeds and the bulk of the bag goes to waste. The cheap mix is the most expensive way to feed a cardinal.
The feeder placement that does the other half
Food does not work if the cardinal will not come to it. The setup that brings him daily:
- Hopper or platform feeder. Tube feeders with short perches are sized for chickadees. Cardinals need space to perch and a flat or curved surface.
- Within three metres of dense cover. Holly, juniper, dogwood, evergreen shrub. The cardinal will not feed in the open.
- Ground feed as well. Scatter sunflower on bare ground or fresh snow under the shrub. Cardinals are natural ground foragers and a lot of winter feeding happens at boot level.
- Stock daily. Especially before storms. Cardinals memorise feeder routes. If you drop off the route they stop checking.
The single most common reason a cardinal disappears from a winter feeder is not predation or migration - it is that the feeder went dry for a week and the bird moved on.
Water in winter is more important than people think
A bird that cannot drink cannot maintain feather function. Feathers depend on regular bathing to compress and trap air. Trapped air is insulation. In sub-zero weather, the bird who can keep his feathers clean is the bird who survives the night.
The fix: a heated birdbath. A 60-watt deicer at the bottom of an existing bath, with a thermostat, keeps the water liquid at temperatures well below freezing. Total operating cost across a winter is roughly the price of a few coffees. It also brings every other bird in the neighbourhood, which is its own reward.
The cardinal flock you did not know existed
Cardinals are paired in summer and territorial. In winter they form loose flocks - Cornell Lab describes them as “a dozen to several dozen birds.” The flock roosts in dense evergreens, forages together, and follows feeder routes. This seasonal shift in social behaviour is why your feeder can go from “two cardinals every morning” in October to “eight cardinals every morning” in January.
By March the flocks dissolve back into pairs and the territorial behaviour returns. The winter sociability is short.
What not to do
- Do not feed bread. Empty calories, fills the bird without nourishing him, accumulates as mush in feeders.
- Do not let suet melt in late winter. A warm March day will rancid suet within hours.
- Do not put up a feeder and let it go mouldy. Dirty feeders spread salmonellosis. Bleach-wash every two weeks in winter, weekly in summer.
- Do not use red dye in anything. It does nothing to attract cardinals (or hummingbirds). Audubon advises against red dye in hummingbird nectar as an unnecessary precaution; the same principle applies to any feeder additive.
