In the field, Arctic charr were subjectively sorted into
the three different morphs (LO-, PB-, and PP-morph)
based on their general appearance. Drawings of the three
Arctic charr morphs were made according to general
observations in field and while photographing the charr
(Fig. 1). Identification was mainly associated with differences
in head and body morphology and coloration combined
with sexual maturation in smaller individuals.
Altogether, 61 individuals of the LO-morph (mean fork
length: 24.8 cm, range: 18.7–31.9 cm), 47 of the PBmorph
(mean: 10.7 cm, range: 7.8–13.7 cm), and 51 of
the PP-morph (mean: 25.4 cm, range: 10.1–44.8 cm) were
included in the morphological analyses (see Fig. A1 for
size distributions).