Sea surface temperature guide

Bigeye Tuna sea surface temperature guide.

  • Thunnus obesus
  • Tuna
  • Agency-reported threshold data

Bigeye tuna live deeper than any other commonly-targeted tuna species — they spend their days at 600 to 1500 feet. Surface SST is less predictive than for yellowfin or mahi. Use SST imagery to identify productive canyons, then fish the structure at depth.

SST threshold gauge

The temperature ranges that matter.

The water temperature ranges that determine where bigeye tuna hold and feed. Hard thresholds (dashed lines) are values outside which fish actively depart or become inactive.

50°55°60°65°70°75°80°85°90°Peak 5972°
Outside toleranceSuboptimalGoodPeak·Dashed line = hard threshold
Optimal range59–72°F
Preferred range50–75°F
Avoid below45°F
Avoid above80°F
Threshold source (Agency-reported) →

Depth profile & SST reliability

Typical depth

2001500 feet

SST as locator

Low — fish location is bathymetry-driven

Bigeye live deep — 600 to 1500 feet during the day, rising at night to feed. Surface SST is a poor predictor of bigeye location. Daytime trolling for bigeye targets the thermocline depth, not the surface temperature.

Current systems & structure

Gulf StreamWarm core eddiesTemperature breaks

Bigeye associate with deep canyon structure and warm core eddies but at depth, not at the surface. Surface SST tells you which canyons might be productive but not whether the fish are there.

Zone-by-zone calendar

Overlap charts by zone.

For each zone where bigeye tuna are present, the chart overlays the zone's typical monthly SST range with the species' preferred and optimal ranges. Months where the bands overlap are when fish are in range.

Mid-Atlantic

Hudson Canyon & New York Bight OffshoreMontauk NY · Manasquan NJ

Best months

May, June, July, August, September, October

MonthZone SSTStatus
Jan4452°FFishable
Feb4450°FOutside
Mar4452°FFishable
Apr4656°FFishable
May5464°FPeak
Junnow6272°FPeak
Jul6878°FPeak
Aug7080°FPeak
Sep6674°FPeak
Oct5866°FPeak
Nov5260°FFishable
Dec4654°FFishable
Baltimore & Wilmington CanyonsCape May NJ · Ocean City MD

Best months

May, June, July, September, October, November

MonthZone SSTStatus
Jan4654°FFishable
Feb4654°FFishable
Mar4856°FFishable
Apr5060°FFishable
May5666°FPeak
Junnow6474°FPeak
Jul7080°FPeak
Aug7282°FFishable
Sep6876°FPeak
Oct6068°FPeak
Nov5462°FPeak
Dec4856°FFishable
Norfolk & Washington CanyonsVirginia Beach VA · Wachapreague VA

Best months

April, May, June, September, October, November

MonthZone SSTStatus
Jan4858°FFishable
Feb4856°FFishable
Mar5060°FFishable
Apr5464°FPeak
May6070°FPeak
Junnow6878°FPeak
Jul7282°FFishable
Aug7484°FOutside
Sep7080°FPeak
Oct6472°FPeak
Nov5664°FPeak
Dec5060°FFishable

Gulf of Mexico

Louisiana Deepwater & RigsVenice LA · Grand Isle LA

Best months

January, February, March, November, December

MonthZone SSTStatus
Jan6472°FPeak
Feb6470°FPeak
Mar6874°FPeak
Apr7278°FFishable
May7682°FOutside
Junnow8084°FOutside
Jul8286°FOutside
Aug8286°FOutside
Sep8084°FOutside
Oct7682°FOutside
Nov7078°FPeak
Dec6674°FPeak

Conservation & regulations

ICCAT / NOAA

Overfished — under rebuilding plan in Atlantic per ICCAT. ICCAT-managed Atlantic stock under rebuilding plan. HMS permit required. Strict bag and size limits. Verify current rules before keeping fish.

Stock assessment source →

Bigeye fishing is canyon-edge fishing at depth. Troll deep-running plugs along the 100-fathom line at sunrise and sunset. SST charts help identify which canyons are eddy-influenced; use bathymetry to find the structure.

Sources

SST threshold data is summarized from agency and research sources. Year-to-year ocean conditions vary; verify current SST imagery before each trip.

See live SST for your offshore zone.

Bield: Fish overlays NOAA CoastWatch SST imagery on your chartplotter view, highlights the temperature breaks that match bigeye tuna thresholds, and alerts you when your home zone hits the 5972°F window.

Start free trial →