Winter bird watching can be exciting for new and experienced birders alike as feeding birds seems easy at first. All you have to do is fill the feeders and watch the birds come. But when the feeders aren’t cleaned regularly, mold can grow on bird seed and can make birds sick. Once the conditions for mold growth are created, mold will grow in bird seed within a relatively short period. Fortunately, there are simple ways to make sure the feeder is mold free, which will ensure birds are healthy and safe to eat from the feeder all season.
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Check PriceReasons Why Bird Seed Molds Fast During Winter
Winter may feel like the perfect time to store food, but winter is actually the biggest time of year for mold in bird feeders due to the ideal conditions for mold growth. It's the freezethaw cycle that occurs over and over that causes the biggest problems. It's not just the moisture contained in the feeder itself.
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Snow covers your bird feeder. During the day, the temperature rises a bit and the snow turns into water. The water collects in the seeds. Overnight the water freezes. The next day the water thaws again. This process creates a cycle that goes on for a long period of time and sets bird food in a moldy state.
Feeder covering can create humidity and condensation, allowing mold spores to develop. Quality bird seed will not stay fresh when it becomes wet. After several days, the risk increases significantly and mold is able to develop before birds can eat the seed.
Most People Make This Mistake: They Overfill Feeders
Most people make the mistake of thinking they are helping the birds by filling their feeders to the top when the temperatures drop.
I understand your reasoning. Less exposure to the cold, and more food available to the birds. However, this is how it really works: the additional bird food just sits there. The birds only eat the seeds at the top, while the seeds at the bottom become clumped and start to grow mold due to moisture. By the time the birds get to the bottom, the seeds have already gone bad.
When feeders are filled too much, they create weight and moisture issues. Seed that is packed too tightly can actually block the feeders drainage holes and prevent water from escaping. It also reduces the feeders ability to circulate air and will trap humidity inside. This means that you will end up with a feeder full of waste that you'll have to dump and clean, which will cost you more time and money than if you just refilled the feeder in smaller amounts more often.
The only solution is a mental shift, instead of filling feeders to the top, try filling them half way, or even less. Record how fast birds clear the feed, then respond accordingly. If they clearing the feeder every day, put in a little more next time. If there is still seed after 3 days, you are putting out way too much seed. Let the activity of the birds guide how much you put in. Not the capacity of the feeder.
Five Practically Possible Methods to Prevent Moldy Seed This Season
Keeping mold at bay can be achieved with just a few simple strategies. Here are five ways to effectively keep seeds dry and fresh:
Feeders that support drain holes and air circulation should be chosen. As do platform feeders that have mesh or slatted bottoms that don’t trap water, tube feeders with small drainage holes in the bottom do well. Unless you’re willing to clean daily, avoid solid-bottom feeders. Hopper feeders may work if they have big roof overhangs and ventilation slots.
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Consider weather baffles or covers for your feeders. A basic dome baffle positioned over your feeder will keep rain and snow from accessing the seed. You may also place feeders under natural cover such as roof overhangs or tree limbs, but be certain they are still exposed enough for birds to locate and they are protected from predators.
Storage of bulk seeds is done best in a cool, dry place and airtight container. Improperly stored bulk seeds in a place with condensation, like an outdoor storage shed or garage, will grow mold before you fill the feeder. Winter weather will expose the seeds faster and make them spoil quicker.
Fill feeders when birds are active. Most backyards have a lot of activity in the morning and again in the evening. During busy periods more food will get eaten, so you should fill feeders then. Also, try not to fill feeders in the evening, especially right before it will get cold and will get exposed to moisture from dew.
To get rid of mold spore colonies, clean your feeders every two weeks at a minimum. The winter season is especially bad for moisture so the cleaning should really be done more often so as to prevent problems before they start. The overall health of your feeding station is greatly improved with a quick scrub.
What to do if you see mold (plus how to clean feeders safely)
The presence of moldy seed will be easily noticeable — the seed will appear clumped together, it will have a discolored appearance, and it may even have a fuzzy appearance. Moldy seeds also have musty and sour odors. If you see any black, white, or green growth on the seed or feeder, do not hesitate to take action.
Moldy seeds could be harmful to birds, so first take all the seeds from the feeder. Do not try to salvage the "good" parts because mold spreads with spores, and the whole batch is tainted. Place the sealed trash bag in your trash, not in your yard where birds or other wildlife might eat it. Moldy seeds have toxins that could be very sickening to birds.
Use one part white vinegar mixed with four parts hot water, or for a bleach solution, mix one part bleach with nine parts water. You will also want to take apart each piece of the feeder and scrub all surfaces with a sponge or an old toothbrush. Make sure to get extra scrubbing on the corners, perches, and feeding ports because they are super moldy. You will also want to rinse the feeder with clean water and let it dry in the sun before you refill it.
If a feeder continues to have mold issues even after consistent cleaning, it is probably time for a new feeder. No matter how much you clean a feeder, cracks, scratches, and worn seals provide areas where moisture and mold can build up.
Smart Seed Options for Resistance to Winter Moisture
Different types of bird seed react differently to winter weather. Some types of bird seed stand up to moisture better and last longer in more difficult conditions.
Winter is the time to use black oil sunflower seeds! Their shells offer protection from the moisture of winter and birds love to eat them. They won’t sit around for long periods of time. While shelled sunflower hearts are great because they eliminate a messy feeding area, they spoil more quickly. If you offer these during dry periods it’s best to do so in small amounts.
Safflower seeds are great because the shell is also very hard and resists moisture absorption better than most seeds. They are also less appealing to squirrels which means less spillage waste on the ground.
When wet, nyjer (thistle) can clump, but it remains relatively dry in appropriate feeders with small ports. To maximize drainage, use mesh feeders designed for nyjer.
During the winter, you should stay away from cheap mixed seed. Filler grains that birds do not eat are included in these mixes, leaving unhygienic moisture spots. When wet, millet, corn, and wheat can easily develop harmful mold. Invest a little more into quality single-seed products. You will keep your birds healthier and lose less.
Seeds that are clean and dry are the ones you want to purchase from the store. If the seeds are dusty, broken, or smell funky, they are best left on the shelf. Fresh seeds from the high turnover stores will resist mold better than old stock that has been sitting in the warehouse for a long period of time.
Winter birdfeeding just takes a little extra work than summer birdfeeding, but it is worth it! You should keep the portion sizes small, pick the best seeds, clean the feeders regularly, and protect your feeders from the weather. Your birds will stay healthy, your backyard will look great, and you will enjoy watching your visitors. Happy bird feeding!
