Horseshoe Crab Numbers Increase in Project Limulus Survey

Judy Knowles Reports

Last year there was a significant drop in the number of crabs counted during the standardized survey. The average number of crabs was less than half of what it was in 2010, 2011, and 2012. During those three years the average number of crabs counted was 7.13; last year the average was 3.06 crabs per survey. This year our average was up to 10.24 crabs per survey! This is a huge increase and I am cautiously optimistic. The reason for my caution is that we had one night survey on May 30 when the group counted an unusually large number of crabs during the survey, a total of 97 between the two beaches. We have never counted that many during a survey before! That one night made our average for the season much higher than it would have been had we not gone out to the beaches that night.

The 2014 survey season began on May 12 and ended on June 29. The Project Limulus volunteers surveyed the two beaches at Indian Cove a total of 17 times. Tags were in short supply for Sacred Heart’s Project Limulus and we were only given 100 tags. We didn’t have enough tags for individual taggers this year. All of the crabs were tagged by the group in Indian Cove with the exception of 2 crabs from Joshua Cove (Trolley Rd.), which volunteer Ann Delaney and I tagged when we took them to visit the first and second grades at Kasimir Pulaski Elementary School in Meriden. We used all 100 tags and we could have used more had they been available.

The total number of crabs counted this year was 174. Last year the total was 49.

Recaptures are crabs which are already tagged. Our recapture total was low this year with only 10 recaptures compared to 34 last year. This is puzzling and I have no guess as to why this happened.

My subjective opinion is that we did see more crabs this year, both during the day and night surveys. Let’s hope that this trend continues next year.

I would like to thank all of the volunteers for their enthusiasm and dedication. I would not be able to continue to do this study without your support and encouragement.

(Reprinted from September 2014 Newsletter.)