The Horseshoe Crab, Limulus polyphemus: 200 Million Years of Existence, 100 Years of Study

The Role of Horseshoe Crabs in the Biomedical Industry and Recent Trends Impacting Species Sustainability

“…They were once harvested for fertilizer and livestock feed; but this widespread practice ended in the 1920s, as the stock of horseshoe crabs began to decline and the public nuisance of the strong odor hastened the adoption of more competitive, alternative fertilizers (Walls et al, 2002). Thereafter, the use of horseshoe crabs as bait in commercial fishing became popular in the 1990s.…”

“…Sustaining the horseshoe crab population is also ecologically essential, as they play key roles as: bioturbators; hosts to a variety of epibionts on their shells; controllers of the population of many benthic invertebrates; and as a food source for a multitude of marine animals (Figure 3) (Botton and Haskin, 1984;Botton and Ropes, 1989;Walls et al, 2002;Botton, 2009). Barnacles, slipper limpets and blue mussels frequently live on the shells of horseshoe crabs, although the relationship is mostly neutral (Botton, 2009).…”

“…Shorebirds (e.g., red knots and ruddy turnstones), sand shrimp and fish (e.g., American eel, Atlantic silverside, catfish, devil ray, mullet, northern kingfish, silver perch, summer flounder, striped bass, swordfish, weakfish, white perch and winter flounder) consume horseshoe crab eggs and larvae (Warwell, 1897;Perry, 1931;Price, 1962;Spraker and Austin, 1997;Walls et al, 2002). In turn, crabs (e.g., blue, fiddler, green and hermit crabs) and pufferfish eat juvenile horseshoe crabs (Walls et al, 2002;Botton, 2009).…”

“…The name "horseshoe crab" is derived from the Limulus polyphemus' most recognizable features, its extended prosoma (or cephalothorax), a large shell that resembles a horseshoe (Figure 1). Commonly referred to as a "living fossil, " the horseshoe crab has been able to survive nearly unchanged for an estimated 200 million years (Walls et al, 2002;Kin and Blazejowski, 2014)-prior to recent population dynamics in the face of growing commercial demand. Concerted conservation and research efforts are vital for this species' future wellbeing.…”

“…The American horseshoe crab (Limulus polyphemus) is a valuable keystone species distributed across the Atlantic Coast of the United States and the Gulf of Mexico (Botton and Haskin, 1984;Botton and Ropes, 1989;Walls et al, 2002;Botton, 2009;Sekiguchi and Shuster, 2009). Horseshoe crabs play a key role in the eel and whelk fishing industry and an unparalleled, integral part in ensuring environmental safety and that of nearly every drug and medical device in use today (van Holde and Miller, 1995;Loveland et al, 1996).…”