Susquehanna and Allegheny smallmouth peak as summer heat arrives

What's biting

What's next

Without live gauge readings or a localized weather feed in the current data, the outlook below draws on seasonal patterns typical of late June on Pennsylvania's larger river systems.

**Smallmouth bass window:** First Quarter moon phases tend to dial up bass activity during the 48-72 hour window bracketing the quarter, offering moderate lunar pull without the extreme overnight pressure swings of a full or new moon. On the Susquehanna, expect smallmouth to be most aggressive in low-light transitions: pre-dawn, the first hour after sunrise, and the final 90 minutes of daylight. Main-channel boulders, rocky shoals, and the downstream faces of bridge pilings are reliable contact zones. Per Wired 2 Fish, keeping a Senko-style stickbait on the deck for midday lockdowns is a strong play. A weightless wacky rig drifted slowly through an eddy can produce when faster presentations stall.

**Catfish outlook:** Channel and flathead catfish on both rivers are in peak feeding condition through late June. Fishing the Midwest notes that summer rivers are underutilized fisheries with strong catch rates, particularly after dark. Cut bait or live bream drifted along deep channel bends and in tailwater sections below dams historically produces the heaviest fish. Night sessions on both the Allegheny and the main-stem Susquehanna should be productive heading into the weekend.

**Walleye:** Dawn and dusk remain the most productive windows on both drainages. Crawler harness or jig-and-minnow combos drifted along gravel flats adjacent to deeper structure is the seasonal standard. Walleye move shallower to feed in low-light conditions and retreat to depth once light intensifies, so tight timing windows reward early risers.

**Muskellunge:** Muskie on both drainages are in typical mid-summer holding patterns based on seasonal norms for late June, staging near deep rocky structure and large eddy seams. Large glide baits or oversized swimbaits worked slowly over depth transitions at first light are the standard presentation for this time of year.

**HAB watch:** PA Sea Grant's June 25 webinar underscores a genuine planning consideration. If a blue-green algal bloom develops in a backwater or slow-moving section you plan to fish, avoid contact and do not consume fish from the affected area. The PA Department of Environmental Protection posts active bloom advisories online, and checking before a trip takes minutes.

Context

Late June sits squarely in the heart of the prime access window on Pennsylvania's two major river systems. The Susquehanna runs from New York through central Pennsylvania before emptying into the Chesapeake Bay, and its wide, rock-studded pools and riffles create ideal smallmouth habitat under normal summer flow conditions. The Allegheny, running through northwest Pennsylvania from the New York state line to Pittsburgh, supports a similarly productive mix of smallmouth bass, walleye, muskellunge, and catfish.

At this time of year, most smallmouth have completed spawning, which typically wraps up by late May to mid-June in central Pennsylvania depending on water temperature, and fish are dispersing into summer feeding territories. This post-spawn transition historically marks some of the best topwater and structure fishing of the year as bass aggressively defend feeding lanes. Tactically, this aligns with Tactical Bassin's observation that summer bass become more predictable once structure-driven behavior takes over from spawn-related staging.

PA Sea Grant's announcement of $1.27 million in new aquatic and watershed research funding reflects ongoing institutional attention to Pennsylvania's freshwater resources, with a stated focus on ecosystem and watershed challenges directly relevant to both river systems.

No current feed entries provide direct angler-reported catch rates or this-week on-water conditions from the Susquehanna or Allegheny specifically, so season-to-date comparisons with prior years cannot be made from the available data. Anglers seeking current on-the-water reports should consult the PA Fish & Boat Commission biologist reports directly.