Invader population speeds up life history during colonization

• Published in: Biological invasions 2012-07, Vol.14 (7), p.1501-1513
• Main Authors: Amundsen, Per-Arne, Salonen, Erno, Niva, Teuvo, Gjelland, Karl Øystein, Præbel, Kim, Sandlund, Odd Terje, Knudsen, Rune, Bøhn, Thomas
• Format: Article
• Language: English
• Subjects: Animal populations; Biomedical and Life Sciences; Colonization; Coregonus albula; Developmental Biology; Ecology; Fish; Founder effect; Freshwater & Marine Ecology; Genetic diversity; Genetic markers; Genotype & phenotype; Growth rate; Heterozygotes; Invasions; Invasive species; Life cycles; Life history; Life Sciences; Life span; Marinbiologi: 497; Marine biology: 497; Matematikk og Naturvitenskap: 400; Mathematics and natural science: 400; Mortality; Nonnative species; Original Paper; Physical growth; Plant Sciences; Population biology; VDP; Zoologiske og botaniske fag: 480; Zoology and botany: 480
• ISSN: 1387-3547; 1573-1464
• DOI: 10.1007/s10530-012-0175-3

We explore the long-term developments in population biology and life history during the invasion and establishment of the fish species vendace Coregonus albula in a subarctic watercourse by comparing life-history traits and molecular genetic estimates between the source and the colonist population. The two populations exhibited highly contrasting life-history strategies. Relative to the source population, the colonist population was characterized by slower somatic growth rates, earlier sexual maturation at smaller individual size, higher mortality rates and a shorter life span. The two populations could also be significantly discriminated by the genetic markers. Limited founder effects were detected from heterozygote deficit and reduced allelic richness in the colonist population, but both populations were associated with relatively high genetic diversity. The study reveals that the invasion into a new environment induced large changes in life-history strategy, with typical r -selected traits being more prominent in the colonist than in the source population. We discuss the mechanisms that may explain the observed life-history differences between the source and the colonist population, and argue that the accelerated life history of the colonist population represents an adaptive pioneer strategy aimed at fast population increase during colonization and establishment.