Lakeville fisheries commission sets May 2 cutoff for herring ladder counts after repeated "fallbacks"

The Town of Lakeville Herring Fisheries Commission voted Wednesday to set the end of May 2 as the cutoff for this season’s manual herring ladder counts, citing repeated “fallbacks” — fish moving back down the ladder after appearing in the counting area — that made later tallies unreliable.

Commission members said the pattern of fish repeatedly moving up and then back down through the ladder produced unusually large, transient counts on some days and therefore risked producing misleading data for state estimates.

The commission’s action followed several days of discussion during which members described sequences of short-term spikes and repeated appearances by the same fish. Members reported typical early-season behavior followed in early May by multiple events when counts jumped (several counts in the hundreds, and individual tallies referenced in the meeting that reached roughly 1,000) then fell again within minutes. The commission concluded those later counts could not be reliably distinguished from repeat passages and agreed to stop including counts taken after May 2 in the formal, public record used for state reporting.

The commission also asked staff to record the issue in the season’s documentation and to include an explanatory note to the state fisheries office indicating that counts after May 2 were excluded because fallbacks made validation impracticable. Members discussed but did not adopt equipment changes at the meeting; the transcript records questions about electronic counters and whether such technology would register repeat passages differently, but no formal decision on equipment was made during the session.

Commissioners also discussed related operational issues: river levels and dam board settings that affect ladder flow, whether sections of the ladder should be screened or gated to limit public access near Wareham Street if a planned park draws more visitors, and the trade-offs between access for maintenance and public safety.

The commission’s motion to set the cutoff and include an explanatory note was moved and seconded and approved by the members present. The commission recorded an instruction that the fisheries estimates submitted to the state distinguish the validated counts (through May 2) from later counts that the commission considers unreliable.

Members noted the unusual nature of the year’s pattern — several said they had not observed such pervasive fallbacks in their years of service — and recommended monitoring in future seasons and notifying state fisheries if the pattern recurs, so that broader technical review or an equipment trial could be considered.

Next steps recorded by the commission include documenting the reason for the cutoff in the season file submitted to the state and flagging the event for follow-up in future seasons.