Saltwater · Late spring and summer best, May to August, when males guard nests inshore
Plainfin Midshipman
Porichthys notatus
The 'singing fish' of the Pacific coast: on late-spring and summer nights, nesting males hum for hours to court females — a drone once famous as the mysterious houseboat hum heard in Sausalito. Rows of light organs (photophores) along its belly look like the brass buttons on a naval midshipman's uniform, which gave the fish its name. Mostly a night-time pier and bay bycatch that steals small baits, it is released unharmed.
Seasons · Peak
Identifying features
- Rows of small photophores along the belly and lower head — like a midshipman's uniform buttons
- Broad, flattened toad-like head with eyes set high and a wide mouth
- Plain olive-brown back with NO spots on the body — 'plainfin' and 'notatus' is plain-backed
- Four lateral lines run along the body, more than most fish
- Soft, scaleless skin and a rounded tail; fins plain and unspotted
Habits
- Males hum at night in late spring and summer by vibrating the swim bladder against the nest
- Nesting males dig under rocks and shells in the intertidal and guard the eggs until they hatch
- The famous humming has kept houseboat residents awake in Sausalito and other bays
- Feeds at night on shrimp, small crabs, squid and small fish
- By day it buries in soft bottom or hides under cover; a common bait-stealing bycatch at docks
Distribution
Where to find them
- Puget Sound docks and bay piers at night in summer
- San Francisco Bay and Sausalito shorelines in humming season
- California bay and harbour docks over mud bottom
Where they live
How to catch them
Small baits in bays around docks at night Shore
Rig: Light rod, small bottom rig with size 4-2 hooks and shrimp or squid pieces fished by docks and harbour lights at night — a humming bycatch
Bait/lure: Shrimp pieces, squid strips
Key tip: Listen on still summer nights: if males are humming under the shore, midshipman are nesting close in — release them on their nests.
Pier fishing in summer over nest areas Shore
Rig: Light to medium rod, dropper bottom rig with small baits over mud and shell bottom near rocks and piers in summer
Bait/lure: Cut bait, shrimp
Key tip: Males guarding nests strike small baits hard in summer; handle gently and release — they are tending eggs.
Best baits & lures
Baseline setup
- Rod: Light to medium 6-7 ft spinning rod
- Line: 8-12 lb mono
- Terminal: Size 4-2 hooks, small bottom rigs, 1-2 oz sinkers
Recommended gear for this species
Rod · Best value
9' 5-weight fly rod outfit
≈ US$180-260
Covers chironomid lakes and small rivers with one setup.
Flies · Budget
Chironomid assortment (30 patterns)
≈ US$25-40
Chironomids are 60% of a lake rainbow's diet in spring.
Picks come from our rule library — never paid placements. Prices are guides; affiliate links may earn us a commission.
Typical size
Common 8-12 in (20-30 cm); large to about 15 in (38 cm)
On the table
Poor — soft and not eaten; release it unharmed.
Similar species
Oyster ToadfishOyster toadfish is an Atlantic fish with a fleshy, warty head, skin flaps on the chin and no photophore rows; plainfin midshipman is Pacific, with button-like photophores and four lateral lines
Pacific Staghorn SculpinStaghorn sculpin has antler-like spines on the cheeks and a scaled, armoured look; midshipman has smooth scaleless skin, photophore rows and no big cheek spinesRegulations vary by area and can change in-season — always check the official rules for your area before you fish. Regulations guide →
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