I would just keep trying. Some ducks may never be that friendly some won't leave you alone. I have 2 khaki drakes and they do not like to be held. Offer lots of yummy treats and spend alot of time with them and hold them as often as you can. He may come around for you. Here is a good treat list.
Here is a HUGE list of other oods you can give your duckies:
Diet Supplements:
Romaine Lettuce (other dark lettuces, not iceberg)
Tomatoes
Worms
Nigh Crawlers
Cucumber
Cracked Corn
Eggplant
Peas
Bell peppers
Carrots
Eggs (scrambled or hardboiled chopped with shells on)
Beans (overcooked)
Feeder goldfish/minows/guppies
Plain yogurt
Mealworms
Broccoli
Cabbage
Brussel sprouts
Cauliflower
Beets
Asparagus
Special Treats:
Floating Koi Food (they love this stuff in their bath or pond, good protein)
Cottage cheese
Apples (applesauce)
Bananas (no peel)
Marigolds, pansies, clover (from a florist or homegrown, no pesticides!)
Pears
Peaches
Cherries
Grapes
Melons (cantaloupe, watermelon)
Squash
Pumpkin
Pomegranate
Turnips (cooked)
Raisins
Zucchini
Oatmeal (cooked)
Strawberries
rice (cooked, small amount)
These Treats are No-Nos!!!!
Bread
Crackers
Spinach
Onions
Potatoes
Avocados
Seeds of any kind
Chocolate
Sugar
Junk food of any kind
Nuts
Citrus (lemons, grapefruit, oranges, limes)
Popcorn
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Remember this motto to live by: Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body, but rather to skid in sideways, chocolate in one hand, wine in the other, body thoroughly used up, totally worn out and screaming 'WOO HOO what a ride!'
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