Even more teeny than tobiko is masago, which is the roe of the capelin fish. Capelin is a type of smelt found in Arctic waters. Their roe is very small and orange in color, and is a popular addition to sushi.
Capelin is a sustainable fish found in large quantities, so eating masago sushi is an ocean-friendly option. Iceland is the world's largest producer of capelin roe, and their fishery practices are environmentally friendly.
Masago is sometimes mixed with wasabi and marketed as wasabi caviar.
Where To Buy Masago:
• Catalina Offshore Products
• Gourmet Food Store
Related:
Ingredient Spotlight: Tobiko (Flying Fish Roe)
Ingredient Spotlight: Salmon Roe (Ikura)
(Image: Kathryn Hill)
Martha Concrete Lam...

Wait, so which is smaller? This says masago is smaller, but on the tobiko article it says tobiko is smaller...
Masago is in fact smaller although not by a great deal. They both run from 0.5 - 0.8mm, but tobiko is more often near the top and masago near the bottom.
Perfect on my sushi, not so perfect stuck in my teeth!
Kathryn,
I've been meaning to leave a comment for ages telling you how much I love these "spotlight" posts! The photos are always beautiful and I love learning more about random ingredients.
Thanks!
@shayna r thank you for the nice compliment! :)
Om nom nom nom.