Appearing Frequently
Infesting
noun, verbal noun
しゅつぼつ
頻度 （ひんど） Frequency
頻発 （ひんぱつ） Frequent Occurrence, Occur Frequently
頻繁 （ひんぱん） Frequent, Incessant
頻りに （しきりに） Frequently, Repeatedly, Often
出没 （しゅつぼつ） Appearing Frequently, Infesting
Seagulls started Appearing Frequently, so they decided to shoot しゅつ them from boats ぼつ
Zombies started Infesting the land, so people fled to schutz しゅつ (protection in German) boats ぼつ