Imposex in dog welks
What is it:
Imposex is the development of male sexual characteristics (the formation of a vas deferens and growth of a penis) in female dog whelks. The common dog whelk, Nucella lapillus, is a marine snail. It is abundant on many rocky shores, where it feeds on barnacles.
Links to Scotland's Marine Atlas:
This information page is part of the theme:
![](https://marine.gov.scot/sites/default/files/styles/large/public/imposex_in_dog_whelks.png?itok=LHPBFlhw)
Imposex in dog whelks © SEPA