title: Ctenophore population recruits entirely through larval reproduction in the central Baltic Sea.
abstract: The comb jelly Mertensia ovum, widely distributed in Arctic regions, has recently been discovered in the northern Baltic Sea. We show that M. ovum also exists in the central Baltic but that the population consists solely of small-sized larvae (less than 1.6 mm). Despite the absence of adults, eggs were abundant. Experiments revealed that the larvae were reproductively active. Egg production and anticipated mortality rates suggest a self-sustaining population. This is the first account of a ctenophore population entirely recruiting through larval reproduction (paedogenesis). We hypothesize that early reproduction is favoured over growth to compensate for high predation pressure.
authors.affiliation: Centre for Ocean Life, DTU-Aqua, Technical University of Denmark, Kavalergården 6, 2920 Charlottenlund, Denmark. coja@aqua.dtu.dk
authors.forename: Cornelia
authors.initials: C
authors.lastname: Jaspers
authors.forename: Matilda
authors.initials: M
authors.lastname: Haraldsson
authors.forename: Sören
authors.initials: S
authors.lastname: Bolte
authors.forename: Thorsten B H
authors.initials: TB
authors.lastname: Reusch
authors.forename: Uffe H
authors.initials: UH
authors.lastname: Thygesen
authors.forename: Thomas
authors.initials: T
authors.lastname: Kiørboe
mesh_terms: D000818:Animals; D001454:Baltic States; D037302:Ctenophora / Q000502:physiology*; D004247:DNA / Q000378:metabolism; D005843:Geography; D007814:Larva / Q000502:physiology*; D008675:Metamorphosis, Biological; D009792:Oceans and Seas; D011235:Predatory Behavior; D012098:Reproduction; D012621:Seasons
chemical_list: D004247:DNA