Photo by Lauren Owens Lambert.

First some great news! To enhance the protection of spawning horseshoe crabs, the Massachusetts Division of Marine Fisheries recently adopted a new restriction on the harvest of them. The new regulation prohibits the harvest of horseshoe crabs from April 15-June 7 (during the crab’s spawning season) in all Massachusetts waters. This extended spawning closure replaces the previous lunar closures, which prohibited harvest for the five-days around each new and full moon from April 16 through June 30. Because this new regulation does not take effect until April 26, the current lunar closure rules apply until that date. Consequently, with this year’s April full moon occurring on April 23, harvest this month will be prohibited during the period April 21-25 under the current rules, and will remain closed from April 26 through June 7 due to the recently adopted regulations. Starting in 2025, the spawning closure will begin on April 15 and run through June 7. This change is critical in protecting this species during their most vulnerable and critical lifestage.

Night horseshoe crab survey photo by Beth Howard.

This May and June, for the sixteenth 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 3-4 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, and 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. There are three daytime surveys ( late morning, midday, and early afternoon) and three nighttime surveys (late evening, midnight, and early morning).

If you would like to volunteer to help with the 2024 surveys, please sign up here.

Teams will be assigned to each date prior to each survey round based on overall coverage. 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).

There will be trainings held on Thursday, April 25 at 12:30pm and Sunday, April 28 at 2:30pm for new volunteers and those who need a refresher.

Survey times:

Date Day Moon Day High Tide 1 Night High Tide 2
5/5/2024 Sun 8:45am – 10:15am 9:15pm – 10:45pm
5/7/2024 Tue New 10:45am – 12:15pm 11:00pm – 12:30am
5/9/2024 Thu 12:15pm – 1:45pm (Fri 5/10) 12:30am – 2:00am
5/21/2024 Tue 10:00am – 11:30am 10:15pm – 11:45pm
5/23/2024 Thu Full 11:30am – 1:00pm 11:30pm – 1:00am
5/25/2024 Sat 12:45pm – 2:15pm (Sun 5/26) 1:00am – 2:30am
6/4/2024 Tue 9:30am – 11:00am 9:45pm – 11:15pm
6/6/2024 Thu New 11:15am – 12:45pm 11:30pm – 1:00am
6/8/2024 Sat 12:45pm – 2:15pm (Sun 6/9)  1:00am – 2:30am
6/19/2024 Wed 9:30am – 11:00am 9:30pm – 11:00pm
6/21/2024 Fri Full 11:00am – 12:30pm 11:15pm – 12:45am
6/23/2024 Sun 12:30pm – 2:00pm (Mon 6/24) 12:45am – 2:15am
Survey dates marked with a different date next to the time take place past midnight, and fall on the day following the sampling date.