Apple Podcasts can use a significant amount of storage if you have a lot of episodes downloaded to your device. Here are a few reasons why this might be happening:

1. Downloaded Episodes: If you have chosen to download episodes for offline listening, these files can take up a significant amount of storage. Depending on the length and quality of the podcast, a single episode can be anywhere from a few MB to over 100 MB.

2. Subscriptions: If you're subscribed to many podcasts, new episodes might be automatically downloading to your device. This can quickly add up and use a lot of storage.

3. High Quality: Some podcasts offer high-quality audio files. While these can provide a better listening experience, they also take up more storage.

4. Cached Data: The app also stores data like show notes, artwork, and other information about the podcasts you listen to. Over time, this can also use up storage.

Here's how you can manage your storage:

1. Delete Downloaded Episodes: You can manually delete episodes you've already listened to or aren't interested in.

2. Adjust Download Settings: You can adjust your settings to avoid automatic downloads, or limit downloads to only when you're connected to Wi-Fi.

3. Limit Episode Keep: In the settings, you can also limit the number of episodes to keep. This can be set to the most recent 5, 10, or all episodes.

4. Clear Cache: Occasionally, you might need to clear the cache to free up some storage. This can usually be done from the device's storage settings.

Remember to always keep an eye on your storage and manage your podcasts accordingly to ensure your device doesn't get filled up.