Waterlands

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Summer flounderShoulder season

Cape · Massachusetts

Castle Island

42.34°N · 71.01°W · Cape · Boston Harbor

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Best score today · 5 PM · Summer flounder

80/100Great
Now
5110 PM EDT
Best window
10 PM-12 AMEbb tide
Tide now
Ebbing4.5 ft ▼

Data from: NOAA CO-OPS + NDBC + ECMWF + Open-Meteo Marine · Waterlands engine

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24-hour conditions · rolling from now

Conditions · 10 PM · now

Time10PNOW
Score51Good
Tide4.5 ft ▼Ebbing
CurrentEbb0.1 kn · toward SE
Wind5 kn SSEgusts 10 · steady
Sea stateLight chop1.1 ft · 6 s
Air temp56°Mild
WeatherOvercast98% cloud
Water65°FObserved

Current regulations

What you can keep here today

IN EFFECT NOW

No rule for Summer flounder is on file here yet, so its status is unknown, not closed. Confirm limits with MassDMF before you keep a fish.

Seasonality · 52-week view · this week ringed

When Summer flounder is best here

Shoulder season for Summer flounder · 1 more week at shoulder

Summer flounder season by week of the year. Shoulder season for Summer flounder · 1 more week at shoulder.
  • Peak
  • Shoulder
  • Off
  • Not here
  • This week

Summer flounder in Massachusetts

Spot profile

Castle Island

Depth
5-50 ftNearest water
Structure
Point · Inner · Semi-exposedPoint · drop-off
Season
Shoulder seasonSummer flounder

NOAA NCEI DEM, sampled Sep 13 on a 3.4 m grid. Depths are feet below NAVD 88, not chart datum (MLLW), so they can differ from a chart by a few feet. Not for navigation.

About this spot

Fishing Castle Island

Castle Island is a cape in Boston Harbor, Massachusetts. Depth in the nearest water is 5-50 ft, with a drop-off. Its profile reads point, inner water and semi-exposed.

Waterlands scores 10 species here; the best right now are striped bass, black sea bass and Atlantic cod. It is peak season now for striped bass, black sea bass, Atlantic cod and bluefish, and shoulder season for tautog and summer flounder. Striped bass peak from May through June and from September through October. Black sea bass peak from June through July and in September. Atlantic cod peak from May through June and from September through October.

Tackle & technique

Summer flounder
Summer flounder lie half-buried on sand and shell bottom and ambush bait along channel edges, inlet bars and ocean reefs, from a few feet deep in back bays to about 100 feet offshore. Drift with the tide and bounce a bucktail tipped with a squid or fish strip along the bottom. The bigger fish move to ocean reefs and wrecks in late summer, so follow them out.
Striped bass
Striped bass feed where moving tide pushes bait past structure: inlets, points, jetties, bridge pilings and rips in the surf, usually in 2 to 40 feet of water. Fish dawn, dusk and night hardest, casting plugs, bucktails and soft plastics or drifting live bunker and eels, and chunk bait on the bottom in current. In midsummer the larger fish drop deeper or feed mostly after dark.
Black sea bass
Black sea bass hold tight to wrecks, reefs, rock piles and jetties, from 15 feet inshore in late spring to well over 100 feet on offshore wrecks in late fall. Anchor or drift right over the structure and fish a two-hook high-low rig with squid or clam, or bounce a small jig on the bottom. The biggest males sit on the highest relief.

Nearby spots

Other spots within an easy run

  • Reserved Channel

    Channel · 0.7 mi

    76
    Top: Striped bassPeak season
    • Striped bass 76
    • Black sea bass 70
    • Bluefish 65

    5 kt SSEL 12:44 AM · 1.8 ftH 7:01 AM · 7.8 ft

  • Dorchester Bay

    Bay · 0.9 mi

    76
    Top: Striped bassPeak season
    • Striped bass 76
    • Bluefish 72
    • Little tunny 69

    5 kt SSEL 12:48 AM · 1.8 ftH 7:02 AM · 7.8 ft

  • Lower Middle

    Bar · 0.8 mi

    73
    Top: BluefishPeak season
    • Bluefish 73
    • Striped bass 71
    • Little tunny 69

    5 kt SSEL 12:44 AM · 1.8 ftH 7:02 AM · 7.6 ft

  • 70
    Top: Striped bassPeak season
    • Striped bass 70
    • Black sea bass 66
    • Bluefish 66

    5 kt SSEL 12:44 AM · 1.8 ftH 7:02 AM · 7.6 ft

Scores and forecasts are for planning only and can be wrong. Conditions on the water change fast; check the marine forecast before you go. Regulations change during the season, so confirm limits and closures with MassDMF before you keep a fish.