From Valheim Wiki
"Blue-eyes shufflers in muck, the neck are small lizards native to Valheim. Surly and mean-spirited, they will attack on sight and must be 
 destroyed like vermin. They stay near water because the creatures of the land loathe and abhor them.
 Yet no creature is all bad. Their tails are delicious."
Runestone found in the Meadows

Necks are agressive creatures found in the Meadows.