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Southwest region Westmoreland County
Mammoth Dam covers 27 acres in Westmoreland County. PFBC biologists last reported on it in April 2019. It has 4 dates on PFBC's 2026 adult trout schedule, as published Oct 4, 2026. The 2026 advisory has no lake-specific row for it; the statewide one-meal-a-week advice applies.
Apr 2019 survey · 7 years ago
Gear: trap nets, night electrofishing
PFBC Biologist Report: Mammoth Lake (2019), p. 1
Findings are our short summaries of one survey at one time. Every number was checked against the cited page of PFBC's report. We don't rate lakes.
2026 schedule · as published OCT 4
As published Oct 4, 2026 · PFBC: “All stocking events are subject to change without notice.” PFBC schedule
Add Westmoreland County lake dates to your calendar (.ics)
Lakes in PFBC's Stocked Trout Waters program that are not open year-round close to all fishing from February 16 until the trout opener (2026 Fishing Summary, p. 23).
No lake-specific advice for Mammoth Dam in the 2026 list.
Statewide advice: “Pennsylvania has issued a general, statewide health advisory for recreationally caught sport fish: eat no more than one meal (1/2 pound) per week of sport fish caught in the state’s waterways.”
“People who regularly eat sport fish, women of childbearing age and children are particularly susceptible to contaminants that build up over time.”
“Fish stocked from PFBC state fish hatcheries are subject to the blanket one-meal-per-week consumption advisory that applies to recreationally caught sport fish in Pennsylvania.”
DEP: “The advisory listing was current at the time this summary went to press. Fish consumption advisories may have been issued or lifted since that time.”
DEP fish consumption advisories Before you go: check DEP's harmful algal bloom page
Quoted word for word from the advisory for the year shown; advisories may have been issued or lifted since. Not medical advice.
2026 Summary p. 11
Largemouth, Smallmouth and Spotted Bass: 15-inch minimum and 4 a day (combined) from Jan. 1 through April 10 and from June 13 through Dec. 31; catch and immediate release only from April 11 through June 12, with no tournaments. Other species follow inland rules.
Big Bass lakes that are stocked trout waters close to all fishing from February 16 until the trout opener, unless they are open to year-round fishing.
Summarized. The current Pennsylvania Fishing Summary, 58 Pa. Code and posted signs govern.
On PFBC's ice-fishing destination list (retrieved Oct 4, 2026). Species PFBC lists for ice fishing here: Largemouth Bass, Trout (stocked), panfish.
This site has no ice reports; conditions change daily; never assume ice is safe.
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PFBC lists Mammoth Dam on its adult trout schedule for 2026: 4 dates, as published Oct 4, 2026. Dates can change; check PFBC's schedule.
As published Oct 4, 2026: Mar 4, 2026; Apr 10, 2026; Apr 21, 2026; Oct 13, 2026. PFBC: “All stocking events are subject to change without notice.”
The 2026 advisory has no lake-specific row for Mammoth Dam. The statewide advice — no more than one meal (1/2 pound) a week of sport fish — still applies. Not medical advice.
PFBC's April 2019 survey recorded: Black Crappie, White Crappie, Bluegill, Pumpkinseed, Largemouth Bass, Yellow Perch, Brown Bullhead, Yellow Bullhead, Common Carp, Golden Shiner, White Sucker, Rainbow Trout. Surveys record what biologists caught with their gear on those days, not everything in the lake.
Yes. PFBC's special-regulation data and the 2026 Fishing Summary (p. 11) list it in the Big Bass Program: Largemouth, Smallmouth and Spotted Bass: 15-inch minimum and 4 a day (combined) from Jan. 1 through April 10 and from June 13 through Dec. 31; catch and immediate release only from April 11 through June 12, with no tournaments. Other species follow inland rules.
Sources for this page: PFBC Lakes_Point (Oct 4, 2026); PFBC biologist reports (area pages, Oct 4, 2026); PFBC adult trout schedule (as published Oct 4, 2026); DEP/PFBC fish consumption advisory (2026 list, updated Feb 27, 2026); PFBC special-regulation data (Mar 2026); 2026 Pennsylvania Fishing Summary. All sources
Last data import Oct 5, 2026