The first International Conference on Horseshoe Crab's Conservation conducted at Dowling College, USA, (2007) and it's proceedings published by Springer in 2009, prompted the continued research and conservation efforts presented at subsequent conferences and colloquium in Hong Kong, Taiwan, (2011); San Diego, CA, (2014), (CERF); Japan, Sasebo (2015) and an accepted inclusion for a special session on Horseshoe Crabs at the 2017 CERF Conference held in Providence, RI, USA. All these aforementioned conferences contributed manuscripts, posters, workshop "position papers", and oral presentations the majority of which have not been published in total. In 2015, Carmichael et al. had published by Springer the majority of manuscripts from the 2011 Hong Kong / Taiwan conference. However, workshop results and all subsequent presentations and workshops were not. The Japan conference presented over 40 papers alone. A collection of all workshop summaries, poster presentations and new manuscript submittals (San Diego, CA; Sasebo, Japan; and Providence, RI) as well as products prepared for the IUCN World Congress in Hawaii, (2016), are included potential contributions for review in this compilation now available for global distribution in this Springer Nature publication.

The "Proceedings of International Conferences on the Biology and Conservation of Horseshoe Crabs", thus contains over 50 manuscripts and a diversified collection of documents, photos and memorabilia covering all four of the horseshoe crab species globally: their biology, ecology evolution, educational, and societal importance. This book exposes the impacts that humans have imposed on all four of these species, revealing through the coordinated effort of horseshoe crab scientists with the IUCN, of the worldwide need for a clear conservative effort to protect these paleo- survival organisms from a looming extinction event. Biologists, conservationists, educators, and health professionals will all welcome this book not only for exploration of its pharmacological interest, but also for the mystery of their longevity. This book also clarifies the future research needs and the conservation agenda for the species worldwide. Anyone working or studying estuaries on a global scale, will need to obtain this seminal work on horseshoe crabs.

John T. Tanacredi, Ph.D. is Professor of Earth and Environmental Sciences in the Biology, Chemistry and Environmental Studies Department and Director of the Center for Environmental Research and Coastal Oceans Monitoring (CERCOM) Field Station, at Molloy College, Rockville Centre, New York. He has held Research Associate positions at the Wildlife Conservation Society, New York Aquarium -Osborn Laboratories of Marine Science; at The American Museum of Natural History, at the Lamont Doherty Earth Observatory, Columbia University, and co-chair of the Conservation Committee of the Explorers Club. A Research Ecologist for 26 years in the US National Park Service, serving as Chief of the Division of Natural Resources and as one of the NPS's Coastal Natural Resource Specialist duty stationed for 9 years at the Graduate School of Oceanography, University of Rhode Island, Narragansett, RI. An Environmental Analyst of the U.S. Coast Guard, Bridge Administration preparing NEPA environmental impact statements for bridge and highway construction in six eastern US states and was a U.S. Navy Flight Meteorologist "Hurricane Hunter"

Dr. Tanacredi received his doctorate in Environmental Health Engineering from Polytechnic University, M.S. degree in Environmental Health Sciences from Hunter College, Institute of Health Sciences, CUNY and BS in Biological Sciences from Richmond College, CUNY

He has published over 65 peer reviewed scientific research publications, written, and edited 7 books and has been included and interviewed in a host of TV, Radio, and Social Media Outlets.

His co-edited book "Conservation and Biology of Horseshoe Crabs", Springer, 2009 was one of the initiating factors in conducting the subsequent Asian Horseshoe Crab Conferences providing considerable support for including all four Horseshoe Crabs species on the IUCN's "Red List". His latest book, "The Redesigned Earth: An Introduction to Ecology for Engineers as if the Earth Really Mattered" (2019), by Springer- Nature, has received rave reviews.

Dr. Mark L. Botton is Professor of Biology in the Department of Natural Sciences at Fordham University - Lincoln Center in New York City, and Co-Director of the Environmental Science Program. He received his Bachelor's degree in Biology from Stony Brook University, his Master's degree in Biology from Brooklyn College, and his Ph.D. in Zoology from Rutgers University. Dr. Botton has published over 70 articles and book chapters on various aspects of horseshoe crab biology, including feeding ecology, mating behavior, the effects of pollution on developmental success, and population and conservation biology. He is the Co-Chairman of the Horseshoe Crab Specialist Group, IUCN Species Survival Commission.

Dr. Paul K.S. Shin is a retired Associate Professor at the City University of Hong Kong, Hong Kong SAR, China and a Fellow of the Chartered Institution of Water and Environmental Management in the UK. He is a benthic ecologist with research interest in community structure analysis, marine pollution and coastal conservation. He has been involved in the study and conservation of horseshoe crabs for the past 15 years. In collaboration with the Ocean Park Conservation Foundation, Hong Kong, he and Dr. S.G. Cheung initiated the Juvenile Horseshoe Crab Rearing Programme to promote conservation education to young generations through hands-on experience in taking care of juvenile horseshoe crabs at schools with subsequent release of these juveniles back to the wild. Dr. Shin received the Medal of Honour from the Hong Kong SAR Government in 2015 for his contribution to conservation and public services. Currently, he serves as the Co-Chair (South East Asia) of the IUCN SSC Horseshoe Crab Specialist Group.

Yumiko Iwasaki, Ph.D. Based on the fossil specimens from the Altiplano, Bolivia, she worked on the phylogenetic studies of the Devonian trilobite group, Phacopidae and a reconstruction of the Devonian paleobiogeography at American Museum of Natural History, NY, with Dr. Niles Eldredge who taught her the value of trilobites as (once) living beings. After receiving a Ph.D. degree in Geology and Paleontology (Invertebrates) from the Earth and Environmental Sciences, Graduate Center, City University of New York, she was hired as a Full-time Faculty at Dowling College, located along the shore of Great South Bay, Long Island, NY where her research interest extended to the behavioral studies of "living fossil," horseshoe crabs. Her research on their juveniles continued at Fordham College at Lincoln Center, NY where she worked as a visiting scholar. A successful coordination between the Japanese host team and IUCN Horseshoe Crab SSG Steering Committee for the 3rd International Workshop on the Science and Conservation of Horseshoe Crabs in Sasebo, Japan, in 2015 granted her to serve as a co-chair. Since then, she has been active to connect the horseshoe crab communities around the globe. Currently a research affiliate at Molloy College & CERCOM (Center for Environmental Research and Coastal Oceans Monitoring), IUCN SSC Horseshoe Crab Specialist Group member, and an advisory committee member at Japan Society for the Conservation of Horseshoe Crab.

Dr. S. G. Cheung is a marine biologist with primary interests in the physiological and behavioral ecology of marine invertebrates and their responses to human disturbances such as microplastic pollution, ocean acidification, and hypoxia. He started working on the ecology and conservation of horseshoe crabs in 2005 and is currently a steering committee member of the Horseshoe Crab Specialist Group under the IUCN Species Survival Commission (SSC). In collaboration with the Ocean Park Conservation Foundation of Hong Kong, he has been running a very successful educational outreach program for more than ten years. This program aims to nurture secondary students in their responsibilities and commitment to marine conservation by rearing juvenile horseshoe crabs in their schools. Currently, he is working on the habitat utilization of juvenile horseshoe crabs and the conflict with oyster cultivation.

Dr. Kit Yue Kwan is a marine ecologist based at Beibu Gulf University, Guangxi, China and has a long-standing interest on finding workable solutions to tackle issues of biodiversity conservation in Asian regions. After completing his Bachelor of Science in Environmental Science & Management at City University of Hong Kong, he continued his Ph.D. study on biology and ecology of Asian horseshoe crabs. His findings contributed to the conservation and management of the juvenile populations in Hong Kong waters, as well as explored the use of the juvenile hemolymph constituents as a health indicator for wild populations. Dr. Kwan is now a steering committee member of the Horseshoe Crab Specialist Group under the IUCN Species Survival Commission. Recently, he has organized the 4th International Workshop on the Science and Conservation of Horseshoe Crabs in China, assisted the establishment of International Horseshoe Crab Day, and now leading the Asian Horseshoe Crab Observation Network program. His recent research work focuses on developing minimum standards for collecting/reporting juvenile population information and conceptual frameworks for responsible stock enhancement programs for Asian horseshoe crab conservation.

Dr. Jennifer H. Mattei is a professor of biology at Sacred Heart University in Fairfield, Connecticut, U.S. and has a wide range of interests in population ecology, restoration, and conservation, with over 25 years of experience working in coastal ecosystems. After completing her Master of Forest Science at Yale, a Ph.D. in Ecology & Evolution at Stony Brook, Mattei was a post-doc at Rutgers University where she was part of a team of scientists to be the first to successfully restore coastal forest habitat on top of closed sections of the largest landfill in the U.S. on Staten Island, NY. In 1998, Dr. Mattei started Project Limulus a community research program within Long Island Sound involving horseshoe crab ecology. Mattei is a steering committee member of the Horseshoe Crab Specialist Group, IUCN Species Survival Commission. Her research with Connecticut citizen scientists found that overharvest and loss of habitat are the major factors causing the population's decline. Currently, her research on coastal restoration, employs a whole ecosystem approach that includes installing oyster reefs, saltmarsh, coastal dune grasslands, pollinator meadow and coastal forest habitats