19 June 2014 Tagging Crabs – Tricky, but Worth it! Posted by: Julia Shaw | 2 comments | Share: In late May, a group of Defenders of Wildlife volunteers headed down to the Delaware Bay shore to tag horseshoe crabs. These crabs are a fundamental part of the Delaware Bay’s ecology, and are essential to the life cycle of migratory shore birds, including the highly imperiled red knot. The red knot makes one of the longest yearly migrations of any bird: Nearly 10,000 miles, from the southern tip of South America to its breeding grounds in the Arctic! The Delaware Bay is an important stop as they feast on horseshoe crab eggs to regain their strength before they continue on their journey north. Historically, horseshoe crabs have been used as bait for fishing eels and whelk, and due to their declining number, there is a temporary ban on fishing horseshoe crabs in New Jersey. Their spawning is the only time during the year that they come ashore, and unfortunately this season is just a few short weeks in May and June – leaving us with a very small window of time to monitor the health of this species that so many others depend on. Our evening began when 20 volunteers met for dinner in Cape May Courthouse. Over pizza and salad, guests listened to Shane Godshall of the American Littoral Society and Laura Chamberlain of Celebrate Delaware Bay speak about their work tagging and monitoring horseshoe crabs. Yaron Miller, Defenders’ Director of National Outreach, and I shared ways members can help support the Endangered Species Act, the highly successful legal lifeline for thousands of imperiled species. Our volunteer projects can make a big difference on the ground, but without the protections granted by the Endangered Species Act, the imperiled wildlife we’re working to help would be in much more danger. Defenders of Wildlife members from NJ and PA meet up to travel to Delaware Bay to tag horseshoe crabs. Horseshoe crabs spawning along the beach. Cook’s Beach is especially important during the migratory flyover. The timing overlaps with the horseshoe crabs' spawning, giving migrating birds an important food source during their journey. Shane points out mating crabs. We surveyed and counted the number of crabs on the beach. Kevin Cook records data Shane Godshall trains the volunteers on how to attach the tags. Two male horseshoe crabs gather around a spawning female. Shane applies a tag to a horseshoe crab. There are so many crabs on the beach! Julia Shaw and Shane Godshall tag a crab. After dinner, the group split up and headed to two beaches: Cook’s Beach and Pierce’s Point. In total, we were able to tag 425 horseshoe crabs! These tags will allow scientists to monitor Delaware Bay crab populations, which will support the scientific research of the crab and shorebird populations. As we walked onto the dark beaches, we used our headlamps to scan the shoreline and were treated to the sight of hundreds of crabs spawning. The females dug down into the sand while the males gathered around to fertilize the eggs – a ritual that these “living fossils” have completed each year for millions of years. Volunteers were able to tag the crabs and help with monitoring their numbers along the beach. As the tagging was wrapping up, the crabs finished their spawning and began to retreat back into the ocean. It was a rare opportunity and we were all thrilled to be a part of this important study! Julia Millan Shaw is the Philadelphia Metro. Outreach Representative for Defenders of Wildlife Want to take part in volunteer opportunities near you? Sign up to receive updates from Defenders, and we’ll let you know when an event is coming up in your area. 2 Responses to “Tagging Crabs – Tricky, but Worth it!” normie geske July 13th, 2014 we live at st. teresa beach on florida panhandle. have been perplexed since late fall, oct.-nov, of 2013 when we witnessed an unusual phenomena w/ horseshoe crabs. for a couple of weeks, our shore was littered w/ 100s of these crabs mating. this is a familiar sight annually in mid spring, but had never before seen them mating in the fall. although we notified florida fish and wildlife, we have not received any explanation. as this occurred in the fall following the chesapeake bay storms and flooding which displaced crabs and interfered w/ the natural mating process in that area, i can’t help but wonder if there was any connection. chesapeake bay,on the atlantic, does seem a long way from st. teresa, fl., on the gulf, for residual affects to occur a few months later…just saying! Reply Dale Lenat July 13th, 2014 Fantastic! I want to do this if it’s done again. Reply Post Your Comment Click here to cancel reply. Name (required) Mail (required) (will not be published) You May also be interested in Wolf Weekly Wrap-Up Idaho’s War on Wolves is Taking its Toll; Project Leader for Yellowstone Wolf Program Tells All; Congresswoman Pushes Forward With Plan To Remove Protections for Wyoming and Great Lakes Wolves; Wolf Killed in Montana’s Wolf Hunt Breaking News: Senate Almost Believes in Science The U.S. Senate saying in a 98-1 vote that “climate change is real and is not a hoax” is a pretty big deal. Smallest Cetacean on the Brink of Extinction in Mexico With the rapid decline of the rare vaquitas, we are hopeful that the Mexican government will commit to preserving this unique animal.