The Soft-Shell Clam Mya arenaria: Biology, Fisheries, and Mariculture

Chapter 3: Reproduction and Larval Biology of the Soft-Shell Clam Mya arenaria

Paul V. R. Snelgrove, Brian F. Beal, and Victor S. Kennedy


This chapter addresses the reproductive and larval biology of the soft-shell clam Mya arenaria, beginning with the reproductive cycle, which includes gametogenesis, subsequent gamete release, and resorption of unspawned gametes, and then following with information on larval development and ecology up to and including settlement. Kennedy (2023, this volume) outlines gonad anatomy and Seitz and Hines (2023, this volume) describe the ecology of spat (newly settled, 0-year-class juveniles) and older individuals.

This dioecious, or gonochoric, bivalve includes either male or female individuals; hermaphrodites are extremely rare. After individual maturity, Mya arenaria produce gametes annually during warmer periods within its geographic range, expelling (broadcasting) them into the overlying water column where fertilization occurs and larvae grow and develop until they metamorphose and settle as juveniles to the benthos.

To compare soft-shell clam reproduction with reproduction in other marine bivalve species, refer to Seed and Suchanek (1992) for mussels, Thompson et al. (1996) and Bayne (2017) for oysters, Eversole (2001) for northern quahogs (also known as hard clams) Mercenaria mercenaria, Barber and Blake (2016) for scallops, and Gosling (2015) for bivalves in general. Relevant reviews of larval biology of marine bivalves include Lutz and Kennish (1992) for mussels, Kennedy (1996) and Bayne (2017) for oysters, Carriker (2001a, 2001b) for northern quahogs, Cragg (2016) for scallops, and Gosling (2015) for bivalves as a group.