Q: is the watch band covered by applecare

Device and accessories are covered. What is the problem? Depending on what it is, it may not be, if it is user damage/abuse. That call is for Apple to make after they have examined a device.

Yes unless it's water damage ...

Apple Watch Service Answer Center - Apple Support

Hi

The Apple Watch band is covered under Apple's One-Year Limited Warranty against defects in materials and workmanship, but not for accidental damage.

If you purchased AppleCare+ for your watch, the included band is also covered for up to two incidents of accidental damage (certain exclusions apply, including cosmetic damage).

If you wish to make a claim in either case, contact Apple Support (mail-in service may be available) or make a Genius Bar reservation with a view to having your band checked and to establish any available service options:

• Contact - Official Apple Support
• https://twitter.com/applesupport
• http://www.apple.com/retail/geniusbar/

To check your warranty status if you are referring to the band that was included with your watch (the serial number is on the back of your watch):

• https://checkcoverage.apple.com/