Insects are an important part of many garden birds’ diets, and you can supplement their natural food sources by providing live or dried mealworms. Rich in protein and energy, mealworms are a nutritious option that can be offered to birds year-round.
Mealworms are not actually worms but are the larvae of the mealworm beetle, a type of darkling beetle, native to Europe but that is found worldwide. They are a golden-yellow colour and measure about 2.5 cm in length with a hard exoskeleton that it will molt and shed in order to grow. After its final molt it will turn into a pupa ready for hatching into an adult beetle.
Despite their name, mealworms are not actually worms but the larvae of the mealworm beetle, a type of darkling beetle native to Europe but now found worldwide. They are golden-yellow in colour, about 2.5 cm long, and have a hard exoskeleton that they shed through moulting as they grow. After their final moult, they transform into pupae, which later hatch into adult beetles.
As well as being a food source for wild birds, mealworms are also commonly used as pet food for captive birds, amphibians, reptiles, and fish. They can even be consumed by humans and are sometimes added to tequila-flavoured novelty sweets, though they are not traditionally the “worm” served in tequila. Mealworms are also a popular choice for fishing bait.
| Nutrient | Dried | Live |
|---|---|---|
| Protein | 20 g | 53 g |
| Fat | 13 g | 28 g |
| Fibre | 2 g | 6 g |
| Water | 62 g | 5 g |
Freeze-dried mealworms are available from many bird food suppliers and pet shops, offering a convenient way to feed garden birds without the need to handle live mealworms. These dried mealworms can be served on their own or mixed with other foods such as seeds, nuts, or fruit. They can also be blended into suet to create a fat cake for birds.
During breeding season, soak dried mealworms in warm water until they soften to reduce the risk of baby birds choking on them. Once you begin feeding mealworms, you’ll likely notice that birds consume a surprising amount, which can become an expensive habit. However, if you’re comfortable with the process, it’s possible to breed your own mealworms at home.
To start breeding mealworms, you’ll need several hundred mealworms or adult beetles. Provide them with a home in a container, such as an old biscuit tin or ice cream tub, with holes punched in the lid for ventilation.
Line the bottom of the container with newspaper, cardboard, or hessian sacking. On top of this bedding, add a layer of bran, oats, or other grains, along with a source of moisture like slices of potato, apple, carrot, wedges of cabbage or lettuce, and some bread. This will help maintain the right humidity for the mealworms to thrive.
Introduce the mealworms and place the container in a warm location, away from direct sunlight. Keep the temperature between 21 and 24°C to ensure the mealworms stay healthy.
Check on your mealworms regularly, removing any dried or mouldy food and replacing it with fresh pieces. You’ll also need to change the bedding periodically. If any mealworms die, you can either remove them or leave them for the surviving mealworms to consume.
After a few weeks, the mealworms will turn into creamy-coloured pupae and then tiny black beetles. The beetles will lay eggs, which will hatch into new mealworms, starting the cycle over again.
To begin new colonies, transfer some of the food, which will contain beetle eggs, into a new container.
You can feed the harvested mealworms to your garden birds immediately, or store them in the fridge, where they will enter a dormant state. Be sure to keep some mealworms to grow into adult beetles, so you can start the next generation of mealworms.
Mealworms will attract a range of insectivorous birds to your garden, particularly appealing to the following species:
You can offer mealworms to garden birds in a shallow dish or ground feeder. If you’re feeding live mealworms, ensure the sides of the dish are smooth, straight, and at least 5 cm high, as they may otherwise be able to climb out.
Special mealworm feeders are also available, designed to dispense mealworms as needed while keeping them fresh and dry. To help the birds locate the feeders, scatter some mealworms on the ground nearby.
While mealworms are high in protein, they don’t provide a complete diet for birds. Therefore, they should be offered in moderation, alongside other foods. You can mix mealworms with suet pellets, seed mixes, or fruit to create a more balanced nutritional offering for your garden birds.
At the end of each day, be sure to remove any leftover mealworms to avoid attracting vermin and other pests. Store live mealworms in a cool, dry place, as they will perish at temperatures below 5°C.
It is important not to feed mealworms to hedgehogs. While they may seem like a suitable treat, mealworms contain high levels of phosphates, which can disrupt the delicate calcium balance in hedgehogs. This can lead to calcium deficiency, which negatively affects their health. When consumed in large quantities, mealworms can cause metabolic bone disease (MBD), a serious condition that impairs the hedgehog’s ability to absorb calcium. As a result, hedgehogs with MBD may experience symptoms such as weakness, difficulty walking, and in severe cases, complete mobility loss.
For the well-being of hedgehogs, it’s best to avoid feeding them mealworms and instead offer more appropriate food, such as specially formulated hedgehog food or natural items like insects, earthworms, and fruits. These provide the essential nutrients without the risks associated with high phosphate levels.
Feeding mealworms to birds can be a rewarding experience, but it’s important to ensure that you are doing so in a way that is safe for both the birds and the environment. Proper hygiene and safe handling of mealworms help prevent contamination, the attraction of pests, and ensure that the food remains nutritious. Here are some key precautions to keep in mind:
Mealworms that have been left out for too long can become dry, stale, or mouldy, which could be harmful to birds. Regularly check feeders for leftover or spoiled mealworms and discard them to maintain a clean feeding environment.
Storage containers: When storing dried or live mealworms, ensure they are kept in airtight, pest-proof containers. For dried mealworms, use plastic or glass jars with tight-fitting lids to prevent moisture and pests from entering. For live mealworms, keep them in containers with ventilation holes, such as a plastic tub with a lid, but ensure the lid is not easily accessible to pests.
Temperature control: Live mealworms should be stored at the appropriate temperature to keep them healthy. Ideally, they should be kept at room temperature (21-24°C). If you’re not planning to use them immediately, storing them in the fridge (at temperatures around 5°C) can help slow their metabolism and prolong their life, but make sure not to store them in a freezer, as this can kill them.
Avoid humidity: Excess moisture can cause both live and dried mealworms to become mouldy, which can lead to fungal growth that can be harmful to birds. Keep the storage area cool and dry to maintain the quality of the mealworms and prevent mould development.
Wash hands: Always wash your hands thoroughly after handling mealworms, especially live ones, to avoid the transfer of germs or bacteria. Even though mealworms are not typically harmful, good hygiene practices reduce the risk of inadvertently spreading diseases to your birds or other wildlife.
Use gloves or tools: If you’re squeamish about handling live mealworms directly, consider using gloves or small tongs to place them into feeders. This can make the process more hygienic and help keep your hands clean. Avoid using metal tools that could potentially harm the mealworms, as they rely on being alive to be consumed by the birds.
Secure feeders: Pests like rodents and ants can be attracted to exposed food, including leftover mealworms. To prevent this, ensure that feeders are placed in secure, elevated areas, such as on poles or in trees, where rodents cannot easily reach them. If you are feeding mealworms on the ground, use a ground feeder with a cover to keep pests away.
Clean the feeding area: If you’re scattering mealworms on the ground, clean the area regularly to remove any leftover mealworms or food scraps. Pests like ants or small mammals can be quickly drawn to any food remnants, so maintaining a clean feeding site is essential to avoid unwanted visitors.
Check for mould: Mealworms are susceptible to mould growth, especially if they are exposed to excessive moisture. Mouldy mealworms can be harmful to birds, so check your supply regularly for any signs of spoilage. If you notice any mealworms that appear discoloured, have an unusual texture, or have developed fuzz, discard them immediately.
Pest infestations: Keep an eye out for pests, such as ants, rodents, or flies, which may be attracted to your mealworm storage or feeding area. If you notice an increase in pests, it may indicate that the mealworms are not being stored properly or the feeders are not being cleaned regularly.
