Last spring, when a local angler wanted to catch Atlantic mackerel in Vineyard waters he had to get in a boat and motor more than a mile off Gay Head. This week there is no need for the boat. For the first time in many years anglers are jigging for mackerel off Memorial Wharf in Edgartown and they are getting quite a few; some have caught enough for a holiday dinner. Plus, they are catching plenty of Atlantic herring.