Climate Change Likely Squeezing Dredge Season: Piping Plovers Coming Earlier

CHATHAM – When it comes to dredging area waterways and nourishing beaches, timing is everything. And with warmer weather coming earlier each year — and the earlier arrival of threatened piping plovers — the window of opportunity for dredging just closed a bit more.

 “I wasn’t real surprised, because the folks that do our bird watching were saying the birds are coming earlier and earlier each year,” Coastal Resources Director Ted Keon told the waterways advisory committee last month. Traditionally, dredging, or more specifically the spreading of dredged sand on beaches, has had an end date of April 1 to ensure no disturbance when piping plovers begin their nesting season. The end date on the town’s dredge permits will now read March 15.

 Dredging operations are limited not only by time-of-year restrictions designed to protect plovers, winter flounder and horseshoe crabs, but also by the availability of dredges.

 “This is just squeezing the window of doing work on the Cape, because, since we all use the county dredge for lots of good reasons, [the season is] getting smaller and smaller,” Keon said. “We just lost two more weeks.”

 The permits indicate that, depending on the location, it may be possible to do work outside of those dates, but qualified bird monitors will need to be in place to check for bird activity, to monitor the work and to document whether the birds show up. If they do, “we could still maybe do work, but we’d have to confirm that our work isn’t altering plover behavior or activity,” Keon said. 

 So what’s behind the change in piping plover behavior?

 “The birds seem to be coming back sooner presumably because winters are not as cold, and warmer weather is coming earlier,” Keon said. “I’ve never seen a scientific documentation of that,” he said, but the idea that climate change is the cause is a valid assumption. It also raises the question of whether warming ocean temperatures might be changing the reproductive schedules for winter flounder or horseshoe crabs, potentially further changing the dredge dates. 

 The town has been dredging under a comprehensive permit from the state department of environmental protection that covers “Chatham Harbor and environs,” including much of the harbor as well as areas in Pleasant Bay, the Stage Harbor and Morris Island channels, Mill Creek and smaller areas around town landings such as Ryder’s Cove, Bridge Street, Old Mill Boatyard and Barn Hill Road. The permit, good for 10 years, expired at the end of 2024, despite the town’s efforts to get the permit renewed prior to that time. 

 Federal officials have now chosen a new project manager to review the permit application, and it has become clear that the comprehensive dredge permit will take more time for additional review, Keon said. The two most urgent dredge projects in Chatham, Stage Harbor and Mill Creek, are now being fast-tracked under a separate permit, which the town hopes to receive shortly.

 Mill Creek is now almost entirely closed off by shoaling, “and we are in dire need of nourishment at Cockle Cove,” the beach where the sand will be deposited, Keon said. Shoaling at Stage Harbor is not as severe as in recent years, “but there is a shoal building as usual on the east side of the channel that we’d like to address,” he said. The state has provided a grant that will pay for half of the project, “and I’d like to use it,” Keon said.

 Piping plovers generally prefer broad, flat beaches where they nest in shallow indentations in the sand, scurrying back and forth to the water to feed. There are typically nesting areas on Harding’s Beach, which often receives sand dredged from Stage Harbor, but the birds also nest at Mill Creek, generally right next to the navigation channel.

 “Two years ago I had to have a [bird] monitor on site while we were dredging to make sure that the birds weren’t being disturbed by the activity,” Keon said.