ocean theme first birthday

Under the Sea First Birthday Party

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Party Plans

Inspired by my little one’s LOVE for bubbles, I created this “Under the Sea” theme for a one year old birthday party. This first birthday party is all about ocean animals, fish, bubbles, water and sand. I hope your little birthday baby with love it!

Here is an editable Under the Sea birthday invitation you can print or share.

Ocean themed birthday party invitation printable
(click here for link to invitation)

Party Decorations

For decorations, use shades of blue balloons to look like bubbles and green streamers to look like seaweed. We love this circle balloon frame to attach all the balloons to create a great backdrop for photos.


Once the frame is set up, add stuffed sea animals and green streamers behind to create the complete look.

These hanging fish decorations would also make a fun addition over the party area.

Birthday Party Games & Activities

Since we are dealing with a one year old for this party, you’re a little limited in what activities you can do. Remember to choose things that are simple and don’t require any specific action from your one year old. Most babies do love bubbles! And if you have any other little kids joining as guests for your party, I am sure they will all enjoy a bubble fest! To save you from having to continually blow bubbles, invest in a bubble machine (your kid will thank you later). This one comes with a remote which I think is a neat feature that most don’t have. If you don’t want to get a bubble machine, you could give each guest their own bottle of bubbles and together blow bubbles for the birthday child!

bubble machine for birthday party

If you are lucky enough to live by the ocean (or a lake?) you could have your party on the beach. That opens up a done-for-you activity right there. Or you could get a baby pool and fill it with just a little bit of water and let your little one splash around. Maybe get a few floating fish toys to add to the pool. If your party needs to be indoors, fill the pool with plastic balls and your baby can play in the ball pit!

birthday party by ocean

Party Food & Drink

first birthday smash cake

Of course you want a smash cake so your new one-year-old can get messy and you can get some awesome pictures. Decorate the cake with blue swirls to look like waves, then put a nice “One” cake topper to mark this milestone.

You will want to have either a separate cake or other dessert option for your guests. If your guests include kids, I would suggest a batch of cupcakes. If you have mostly adults attending your child’s first birthday party, consider doing a healthier option like this watermelon cake. The watermelon is pre-sliced in small strips then stacked together to look like a cake. Finish by topping with other fruit.

For snacks, going along with the theme you could serve goldfish crackers if your little one has begun to eat normal food. Another idea would be blue jello cups to look like water. For the older guests, consider a “seaweed salad” with green spiral pasta.

Birthday Party Favors

Since this party is for a one-year-old, I don’t think party favors are necessary. But some ideas could be:

  • a small bottle of bubbles
  • ocean coloring books and crayons
  • sea creatures plush toys
  • bags of Swedish fish, goldfish, or other ocean themed treats

Party Supplies

Links to supplies mentioned in post. (affiliate)

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