Tri-Spine Horseshoe Crab Aquaculture, Ranching and Stock Enhancement: Perspectives and Challenges

Abstract

As a well-known example of “living fossil,” horseshoe crabs are ecologically significant macroinvertebrates in coastal and estuarine ecosystems. The tri-spine horseshoe crab, Tachypleus tridentatus, has been widely utilized for Tachypleus amebocyte lysate production and food consumption since the 1980s, which led to considerable population declines along the west coast of the Pacific Ocean. The declining horseshoe crab population is expected to have ecological and social impacts. Stock enhancement through captive rearing of juveniles is cited as an important alternative to repopulate the native T. tridentatus, which in turn supports sustainable resource utilization and research activities. The hatchery production techniques for this species have gradually developed following the mass culture efforts in Japan since the late 1980s. However, the previous studies have primarily concerned the feed types and husbandry conditions to maximize the growth and survival of the juveniles. Little is known about the practicability and effectiveness of releasing large numbers of hatchery-bred individuals through releasing programs. In this review, we (1) summarize the available captive breeding and rearing techniques, (2) discuss the release strategies that could potentially improve the survival of released juveniles, and (3) identify the future opportunities and challenges in establishing technical frameworks to support responsible stock enhancement programs for T. tridentatus. The information should benefit future horseshoe crab fisheries management efforts in the attempt to restore the severely depleted populations.

Chemically mediated rheotaxis of endangered tri-spine horseshoe crab: potential dispersing mechanism to vegetated nursery habitats along the coast

“…Mating pairs of T. tridentatus were kept in indoor tanks with an approximately 10-cm sediment layer underneath. The released eggs were incubated in hanging baskets from the surface of culture water with continuous, vigorous airflow pumping below the baskets ( Xu et al, 2021 ). Most eggs developed and hatched into trilobite larvae after one-month rearing under the following environmental conditions: temperature 26–30 °C, salinity 32–33 ppt, pH 7.6–7.9, dissolved oxygen 6–7 mg l −1 .…”

Candidate Species for Florida Aquaculture: American Horseshoe Crab Limulus polyphemus

“…Eggs are acquired through artificial breeding, electrical stimulation, or collection of wild eggs. Naturally spawned eggs have a higher fertilization and are easy to collect if proper permits are obtained (Xiu et al 2021).…”

Comparison on Total Phenolics and Flavonoids and Antioxidant Activities of Methanol Extract of Horseshoe Crab (Tachypleus gigas) Eggs

“…Here are four types of horseshoe crab animals scattered worldwide, three of which are found in Indonesia: Carcinoscorpius rotundicauda, T. tridentatus, and T. gigas (14). It has been discovered that coastal communities consume lots of this part of the horseshoe crab egg (15).…”