Horseshoe Crab Spawning Survey 6/14
- Elizabeth Prevost
- Jun 1
- 1 min read
The Massachusetts Horseshoe Crab Spawning Beach Survey has been conducted since 2008. They use this survey to monitor the abundance of horseshoe crabs in the state. The Spawning Beach Survey is dependent on volunteers and volunteer organizations.
More about the Survey
Spawning surveys are conducted two days prior, the day of, and two days after the new and full moons of May and June. Surveys start times are based on the time of high tide, which varies by beach. Sixteen beaches from the South Shore, Cape, and islands are surveyed.
Most beaches conduct surveys on both day and nighttime high tides. Surveys could occur at 3 in the afternoon, or 3 in the morning, depending on the time of high tide. The number of crabs you will see varies by location and date. The most crabs seen in one survey is nearly 3,000. But there are other surveys where you may not see any crabs. Whether you see 0 crabs, or 3,000, they are all important data points.
The survey is conducted by counting the number of crabs by sex that fall within the survey area. You will need waders or other footwear that you don’t mind getting wet. Data sheets, clipboards, and a thermometer are provided.



