Striped bass migrate north in the spring, and they are a little over anxious. They go too far North too fast, and find the water a bit too cold, which forces them to congregate where the water is slightly warmer (I'm ignoring the fact that there are probably some resident as well as spawning fish all the way up to Nova Scotia).
Concentrate on rivers and streams, especially the mouths, in early spring.
The water is simply warmer there, and the fish will congregate there.
You'll probably find ZERO stripers off the ocean beaches, but plenty of stripers in rivers, streams, and bays.
My favorite early spring location is the mouths of streams and rivers on the outgoing tide. I prefer the last two hours of the outgoing for striped bass, but every location is different. Some smaller outflows may be totally dry the last two hours of the outgoing, so obviously you'll need to fish them earlier in the tide.
Other locations that may produce well include flats in rivers and estuaries (usually muddy), and further upstream where runs of alewives, herring, or other spawning smaller fish may congregate.
Personally I've never done well flyfishing for striped bass among spring runs of herring and other bait fish, but some flyfishermen swear by them.
FISH DEEP!
If there is significant current, like at a mouth on the outgoing, you simply NEED a fast sinking line. You might prefer shooting heads, a Teeny line, or maybe a straight #4 or #6 sinking line, but you need to be deep -- or forget about catching fish. They will be feeding on the bottom, not 6 inches off the bottom.
If you are fishing somewhere shallow and somewhat calm, for example a flat, a floating or intermediate line with a sinking fly is the ticket. My friend Scotch John lives on a muddy flat on the Merrimack and retook up flyfishing after a few decades off. He had zero luck his first few weeks the first spring until I made him fish a clouser minnow. The metal eyes on the fly got it just a little deeper, and he started catching first regularly.
After maybe 2-3 weeks, depending on the year and where you fish (keep a log!), striped bass will also be feeding and hanging out off the ocean beaches.
This is when bigger fish start to arrive, although they arrive slowly, and some seasons you may be catching 99% the same size fish all year.
Rivers and streams, especially the mouths, still produce just as in early spring.
The same techniques, flies, tides, and everything else still produce.
Off the beaches off rocks start to produce as well
I prefer fishing off rocky shorelines the best in mid-spring. An intermediate line from shore, or a fast sinker if from a boat, work well. Sparse deceivers are my fly of choice, but experiment. Sometimes adding a short length of lead core line to your intermediate line or using a clouser minnow will get you a few extra inches of depth and get you into the strike zone!
I love spring striper fishing! The only season I like better is fall striper fishing, but it's not quite as exciting as the first few striped bass of the season.
