Birds provide more than just entertainment for your indoor kitty. Some species are pollinators, and others keep the insect population down. (BestReviews)

If all of your attempts to feed the birds in your yard are frustrated by thieving squirrels, you may want to consider a window bird feeder. These attach to a window and not only provide an up-close-and-personal view of the birds you attract but also keep squirrels from stealing all of the food. The Nature Gear Window Bird Feeder is a streamlined bird feeder that attaches well and allows you to see out the window when your winged visitors are not eating.

Consider first the size of the bird you'd like to attract. This matters in terms of how much food the window bird feeder can hold and what the total weight capacity is. If you're looking to attract larger birds, you'll need a sturdier structure with additional attachments to keep the feeder stable against the window.

Window bird feeders are available in a few different materials. Which you choose is largely a matter of preference, but each has pros and cons.

The easiest mounting style is suction cups. Most window bird feeders have two or more that are attached directly to the window.

If you prefer a hanging window bird feeder, keep in mind that you'll need to use a drill to attach it to the window frame. The chains that hold the bird feeder also allow squirrels access to the bird seed.

Strong suction cup attachments are critical. These are the only things standing between a lovely session of bird watching and a cup or two of bird seed scattered on the ground below.

Removable seed trays slide in and out for easy refills. This means you won’t have to take the entire feeder down to serve dinner.

One of the major challenges of window bird feeders is the lack of space for a wide variety of birds. A feeder with multiple levels solves that problem. This provides perches for more birds to feed. Keep in mind, though, that this type of feeder is generally best for smaller birds.

A simple overhang protects bird seed from the weather. Some birds also enjoy dining in dry comfort.

Window bird feeders are an affordable way to keep your feathered friends plump when wild food is scarce. They cost $10-$30, a price that varies depending on the size and quality of the feeder.

A. Although window bird feeders allow for bird watching when it's not possible to go outside, there are a few downsides.

Shy birds may decline to use the feeder due to its proximity to birdwatchers. Some window feeders are also smaller and limit the variety of species you can attract.

Additionally, window bird feeders can be challenging to attach and may require daily cleaning, depending on how often they are used.

A. The best mixes include a variety of foods to attract multiple bird species. If there are specific birds you'd like to see, consider adding the following.

Nature Gear Window Bird Feeder: available at Amazon

Our take: The transparent design allows an unobstructed view from the window when birds aren't there.

What we like: The perch is big enough for larger songbirds to use comfortably, The food tray slides out so you don't have to take the entire feeder down to refill it. The acrylic feeder is sturdy, and the suction cups are strong.

What we dislike: It can become scratched and dirty over time, so you'll need to wash it frequently.

Crepro Window Bird Feeder: available at Amazon

Our take: This is a great choice for climates that get lots of rain.

What we like: The suction cups are strong. Trays hold 2 cups of seed for less frequent filling. This refills easily and has drainage holes so that food dries quickly after rain and does not mold or rot.

What we dislike: This is not large enough for big birds — it's best for finches and house sparrows.

Hampton Direct Skyline Multi-Level Window Bird Feeder: available at Amazon

Our take: This helps to attract a variety of birds with different types of seed on two levels.

What we like: It's like a bird food duplex. Two levels hold different seeds. You can add another level with the optional expansion kit. The seed is covered with a slight overhang to keep it dry. The suction cups are strong.

What we dislike: The copper-toned roof and perches interfere with the window view when birds are not there. If you prefer a clear feeder, keep looking. 

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Suzannah Kolbeck is a writer for BestReviews. BestReviews is a product review company with a singular mission: to help simplify your purchasing decisions and save you time and money.

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