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North and South River Watershed Association

Horseshoe Crab Counting -- 2026

This May and June, for the 18th year, in partnership with the MassBays National Estuary Partnership Program, the NSRWA will be conducting horseshoe crab spawning surveys in Duxbury Bay. To do this, a team of 3-6 volunteers walks/wades along a ~800 meter stretch of the Duxbury Bay shoreline north of the Powder Point Bridge.

  

The team uses poles and rope to define a 5m x 5m square; crabs inside the square are counted, sexed, and the different clusters in which they are arranged (single crabs, pairs, larger groups) are noted. This process is then repeated in approximately 40 squares along the shore.

Surveys occur around the full and new moons in May and June. During each moon phase we conduct three days of daytime surveys and three nights of nighttime surveys. There are a total of 30 individual surveys this year.

Please note that you must be able to walk on sand for about a mile, and that you will be getting wet feet at a minimum (one team member usually is also in the water up to their waist as well).


If you would like to volunteer to help with the 2026 surveys, please select your desired day(s) and shifts below. 
  • Please note carefully that some shifts occur very late at night or very early in the morning.
  • We are asking all volunteers to sign up for no more than 5 shifts to give others an opportunity to participate.
  • For new volunteers, TRAINING IS REQUIRED. Training is also open to those who need a refresher.
Training sessions will be held at Duxbury Beach, at the East end of Powder Point Bridge, on: 
  • Thursday, April 23 at 5 PM
  • Sunday April 26 at 10 AM. 

Unless you plan to attend training this year OR you are an experienced Horseshoe Crab volunteer from previous years, please do not sign up for any shifts.

If you are unable to find a training or if there are no shifts that that fit your schedule, please make the appropriate selection at the bottom of the list of shifts.

Please do not sign up for the Team Leader role unless you have experience with the program and feel confident as a team leader.

Also note that there are questions below the shift selections for you to indicate your experience level.

New this year: you will be doing a "check-in" when you arrive on site for your shift(s) via a mobile app. More directions on that will be forthcoming.

Please note that this program is conducted in partnership with Duxbury Beach Reservation (DBR). When signing up to volunteer for this event you consent for NSRWA to share your contact info with DBR. If you have any concerns with this sharing please reach out to us.

Thank you in advance for considering volunteering for this important project!

There are no shifts available at this time.

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