Linking stages of life history: How larval quality translates into juvenile performance for an intertidal barnacle (Balanus glandula)

Many marine invertebrates with complex life cycles produce planktoniclarvae that experience environmental conditions different fromthose encountered by adults. Factors such as temperature andfood, known to impact the larval period, can also affect larvalsize and consequently the size of newly settled juveniles. Afterdocumenting natural variation in the size of cyprids (the finallarval stage) of the barnacle Balanus glandula, we experimentallymanipulated temperature and food given to larvae to producecyprids of differing sizes but within the size range of cypridsfound in the field. In a set of trials in which larvae of B.glandula were raised on full or reduced rations in the laboratoryand subsequently outplanted into the field as newly metamorphosedjuveniles, we explored the effects of larval nutrition and sizeon juvenile performance. Larvae that received full rations throughouttheir feeding period produced larger cyprids (with more lipidand protein). These larger cyprids grew faster as juvenilesand sometimes survived better in the field than juveniles fromlarvae that had their food ration reduced in the last feedinginstar. For naturally settling barnacles brought into the laboratorywithin 2 days of settlement and fed, we found that initial juvenilesize was a good predictor of juvenile size even after 2 weeksof growth. By manipulating food given to juveniles that werederived from larvae fed either full or reduced rations, we foundthat larval nutritional effects persisted in juveniles for 2–3times the period that larvae experienced altered food rations.