Like his father, he was a natural scientist and he collected mounted animals, fossils, minerals and plants in a museum, started in 1783, at the Söderfors manor. The first specimens were collected in the vicinity of Söderfors. After two years Grill moved on to the birds of the archipelago. He was able to use his connections through his relatives in the trading houses, to send for specimens from Greenland and China. The collections were also increased during his travels and on a journey to England in 1788, he traded a mounted moose for 60 rare birds.
