You can't feed your chihuahua chocolate, but you can dress him or her up for Halloween.

• Bring your costumed canine to the Washington Animal Rescue League's Halloween-themed Paws in the Park happy hour Wednesday at 6 p.m. at the Park Hyatt Washington. $14 gets you two drink tickets, with a portion of the proceeds benefitting the the rescue league.

One day a year, it's ok for your dog to be a frog. (Kai Pfaffenbach/Reuters)

• Help raise money for the Washington Humane Society during Dogtoberfest, Saturday from noon to 4 p.m. at Union Kitchen. There will be food, drink, a doggy costume competition and more.

• Want to scare your water-averse dog? Potomac Riverboat Company in Alexandria is hosting Bark or Treat Halloween Canine Cruises at 10 and 11 a.m. Saturday. Dress up your dog and take a 40-minute cruise set to Halloween tunes. Doggie treats are provided and dogs ride for free, but tickets are $15 for adults and $9 for children.

• Help the Animal Welfare League of Alexandria with a $10 donation to enter your pup in the annual Alexandria Doggie Howl-o-ween Costume Contest. Registration is on a first-come, first-served basis for 50 pups from 4:30 to 5:30 p.m. on Halloween at the Hotel Monaco in Alexandria. Spectators are welcome, and prizes for top costumes include free nights at the Hotel Palomar in Philadelphia and the Hotel Monaco in Alexandria.