Invertebrates
Sea Nettle
Chrysaora quinquecirrha · also called Atlantic sea nettle
By midsummer, a Chesapeake Bay swimmer might encounter dozens of sea nettles in a single afternoon, their golden-brown, striped bells drifting just beneath the surface, trailing thin tentacles capable of delivering a sting no one forgets quickly.
Overview
The sea nettle, Chrysaora quinquecirrha, is a common jellyfish native to coastal waters along the Atlantic and Gulf coasts of North America, especially abundant in estuaries such as Chesapeake Bay. Its long stinging tentacles and seasonal population booms make it one of the more consequential small predators shaping summer coastal life in its range.
A summer visitor that shapes the whole bay
When sea nettle numbers surge in a given season, their presence alone can influence where and when people choose to swim, a reminder of just how much ecological weight a single seasonally abundant jellyfish species can carry.
Status
Least Concern — widespread and often seasonally abundant across suitable coastal habitat along the Atlantic and Gulf coasts.
Sea Nettle: common questions
How painful is a sea nettle sting?
A sea nettle sting is genuinely painful, causing a burning sensation and localised skin irritation from the numerous long, thin tentacles trailing beneath its bell, though the sting is rarely dangerous to a healthy person and typically resolves without serious complications beyond temporary discomfort.
Why do sea nettles sometimes become so common in certain bays?
Sea nettle populations can become seasonally very abundant in certain coastal bays and estuaries, a pattern influenced by factors such as water temperature, salinity, and food availability, sometimes becoming common enough during peak summer months to noticeably affect local swimming conditions.
Does a sea nettle spend its whole life as a jellyfish?
No, like many jellyfish species, a sea nettle alternates between a small, fixed polyp stage attached to a hard surface, where it can reproduce asexually by budding, and the free-swimming, tentacled medusa stage most people recognise as a jellyfish, meaning the familiar drifting form is only part of its full life cycle.
Where does the sea nettle live?
The sea nettle is native to coastal waters along the Atlantic and Gulf coasts of North America, notably common in estuaries such as Chesapeake Bay, where it can become seasonally abundant during warmer months.