Urchin Cookie
Seaweeds are the preferred diet for most urchins (here on the West Coast we use Macrocystis and Egregia species), but are not always easy to obtain. Urchin Cookie is a simple recipe using eggs, carrots, seawater and agar to make seaweed substitute that sea urchins seem to like better than kelp. This could be important if you are in the midwest and there is no seaweed in sight.
  1. Chop up fresh carrots into 1/2 - 3/4 inch pieces and fill to
    the 4 cup line on the blender.
  2. Add two whole eggs, shell and all. Break over the carrots.
  3. Add 20 grams of plain agar (not nutrient agar).
  4. Add sea water to the 4 cup line.
  5. Blend until smooth.
  6. Pour into a glass baking dish and microwave until boiling.
    You will need to stop microwave and stir contents repeatedly.
  7. Let cool and refrigerate.
  8. When solid, cut into strips 1/2 inch by 4-5 inches.

To serve: not too much, as even Urchin Cookie will foul the water. If they have not finished it in 48 hours, remove, wait a day and replace with fresh. Urchin Cookie will keep about a week in the refrigerator. The recipe can be scaled for more or less food. Try a half batch the first time.

Also see Care of Adult Sea Urchins.