Transitional Species Hunting: Targeting Mackerel Runs in San Diego Fall

Fall is when San Diego’s underwater landscape shifts dramatically. Water temperatures drop, baitfish redistribute, and predatory species follow—none more reliably than mackerel. For spearfishers, the months between September and November represent a golden window to hunt quality fish in predictable locations.

Why Fall Mackerel Runs Matter

Mackerel are transitional species in San Diego’s ecosystem. They’re not year-round residents like calicos, nor are they strictly seasonal like bluefin. In fall, they aggregate heavily as they respond to cooling water and shifting baitfish patterns. This predictability makes them ideal targets for spearfishers who understand the timing and location cues.

Pacific mackerel (jack mackerel) and Spanish mackerel both show up in force. Spanish mackerel are faster, more aggressive, and generally larger—often 18–24 inches. Jack mackerel school tighter and hit faster. Both will commit to a realistic baitfish presentation, which is what spearfishing relies on.

Temperature and Timing: The Key Window

San Diego’s ocean temperature peaks in August around 72–74°F, then begins its decline. By mid-September, you’ll see 70–72°F surface temps. This transition triggers mackerel movement. The sweet spot runs from late September through mid-November, when water sits between 68–71°F. By December, temps drop further and fish disperse.

Check Element’s real-time water temperature data before heading out. A drop of 2–3°F over a few days often precedes aggressive feeding. Plan your hunts for the days immediately following a temperature dip.

Prime Hunting Grounds

La Jolla Reefs and Shores: The rocky reefs from Sunny Jim Sea Cave south to Boomer Beach hold mackerel consistently. The depth variation (15–35 feet) and structure create ideal ambush points. Visibility here often exceeds 20 feet in fall, crucial for spotting incoming schools.

Torrey Pines Artificial Reef: This designated site at 40–50 feet depth concentrates fish. Mackerel use the structure for cover while hunting smaller baitfish. Early morning hunts (6–8 AM) here yield the best results.

Point Loma Kelp: The kelp forests west of Cabrillo Point attract mackerel hunting through the canopy. The structure makes stalking harder but rewards patience. Focus on the kelp edges where open water meets dense fronds.

Mission Beach to Pacific Beach Nearshore: The 20–30 foot zone between the pier and the drop-off sees solid mackerel activity. Less crowded than La Jolla, and fish feed aggressively here in early morning.

Hunting Tactics for Fall Mackerel

Baitfish Imitation: Mackerel hunt primarily by sight and lateral line detection. A realistic approach means moving with purpose but not panic. Mimic wounded baitfish—steady glides with occasional jerky movements. Avoid erratic darting that signals unnatural prey.

School Identification: Spotting a mackerel school is half the battle. Look for nervous baitfish behavior—rapid directional changes, tight clustering, surface disturbance. Mackerel schools often push bait toward the surface or into kelp. Position yourself between the school and structure, forcing them toward you.

Depth Zones: In fall, mackerel don’t stay deep. Hunt the 15–35 foot range where they can access both shallow baitfish and deeper structure. Avoid the shallows unless you’re hunting right at dawn when visibility is low and fish are aggressive.

Time of Day: Early morning (6–9 AM) is non-negotiable. Mackerel feed aggressively as light increases. Afternoon hunts are possible but require better visibility and more patience. Avoid midday (10 AM–2 PM) when sun angle makes spotting fish difficult.

Gear Considerations

Use a 6.5–7mm wetsuit. Water temps in fall demand adequate insulation for multi-hour sessions. A 120cm gun handles mackerel well—long enough for distance shots on spooky fish, not so long that it’s cumbersome in kelp. Polespears work if you’re hunting tight cover, but a pneumatic gun gives you reach on schools.

Invest in quality mask and fins. Visibility in fall is often excellent, but only if you can position yourself properly. Good fins let you hold position in current without exhausting yourself.

Reading Conditions with Element

Use Element’s swell, wind, and current forecasts to pick your day. Mackerel hunting improves with 1–2 foot swell (not flat, not large) and light to moderate wind. Strong wind pushes water around, scattering schools. Check the app the night before and commit to your spot based on the forecast.

The Takeaway

Fall mackerel runs aren’t subtle. They’re aggressive, concentrated, and predictable if you understand the temperature window and know the reefs. San Diego’s fall hunting window closes fast—by mid-November, mackerel disperse and water temps drop below the ideal range.

Start scouting now. Use Element to track water conditions, and plan your hunts for the next temperature dip. The mackerel are coming.