Larval life span, larval settlement, and early growth of Evechinus chloroticus (Valenciennes)

Abstract

Development, settlement, and subsequent metamorphosis on several substrata were observed in cultures of Evechinus chloroticus larvae. The period from fertilisation to metamorphosis ranged between 30 and 63 days for larvae collected from spawnings induced at 3 different times. Newly settled sea urchins collected from the field grew about 1 mm per month in aquaria. Correlation of the larval life span with the growth rate of newly settled sea urchins suggested that the earliest spawning could occur was mid‐November. This finding corroborates the results of previous histo‐logical studies of the gonads of adult sea urchins in the Hauraki Gulf, New Zealand.

Key words:

• Evechinus chloroticus
• sea urchins
• larvae
• recruitment
• metamorphosis
• growth
• spawning
• populations

Notes

Present address: Southwest Fisheries Center, La Jolla Laboratory, National Marine Fisheries Service, La Jolla, California 92038, United States of America