Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2017

Erindi/veggspjald / Talk/poster V47

The interplay of egg size, temperature and social environment for phenotypic diversity in fishes

Höfundar / Authors: C. A.-L. Leblan (1), Skúli Skúlason (1), and D. Benhaïm (1)

Starfsvettvangur / Affiliations: 1. Department of Aquaculture and Fish Biology, Hólar University College, Sauðárkrókur, Iceland

Kynnir / Presenter: Camille A.-L. Leblanc

Egg size as a determinant of offspring size has been well studied. Patterns of growth and life history are commonly studied in connection with temperature, egg size and social environment but the interaction of these factors remains poorly understood.
We studied in Arctic charr, Salvelinus alpinus, the interaction between size at first feeding and environment in terms of temperature and social conditions (group vs isolation). Growth and foraging behaviour were compared between juveniles coming from small and large eggs kept at 4.5°C or at 6.5°C, and observed in group or in isolation from first feeding until 5 weeks later.
Temperature and social environment interactively affected growth. Charr raised at 6.5 °C were larger than those at 4.5 °C. Within each temperature charr coming from larger eggs were larger than charr coming from smaller eggs. Smaller charr raised at higher temperature did not catch up in body mass with larger fish raised at lower temperature. Temperature and social environment primarily affected the probability of foraging in young charr. The probability of foraging was higher at 6.5°C, but the difference in probability of foraging between charr in group and isolated fish was stronger at 4.5°C. Egg size had little effect on behaviour.
This study illustrates the importance of considering the interplay of several factors to better predict consequences of sudden environmental changes on early life histories of fishes.