Blue blob creatures invade California beaches
Strange creatures from another realm are invading the beaches of Southern California, but they’re not extraterrestrials. The blueish blobs washing up by the millions are by-the-wind sailors (Velella velella), a variety of colony creature that spends its life drifting with the breeze on deep, warm ocean waters.
The masses of blue, jelly-like floaters were first reported by Nona the Naturalist with Dana Wharf Whale Watching on Saturday, (April 8, 2023) during an observing cruise off the Southern California coast.
Nona described the encounter for her viewers:
The water is also full of hundreds of these organisms. These are called by-the-wind sailors. They feed on algae and zooplankton in the water, and organisms like our ocean sunfish love to eat these.
What are these things?!
By-the-wind sailors are technically not true jellyfish, nor are they individual animals. Instead, the approximately 4-inch (10-cm) oblong masses are colonial hydroids.
Marine biologists at San José State University give a good description of their lifestyle:
In these communal groupings, individual polyps are connected and share resources through a hydrocaulus [a hollow stem inside individual polyps]. Colonial hydriods have specialized individuals, or zooids, that exist to fulfill a specific need in the colony. For example, the most common type of zooid is a gastrozooid, which provides the colony with food. Gonozooids are used in reproduction, while in some species nematocyst-filled cells called cnidocytes aid in defense.
Leave the blue blobs alone
By-the-wind sailors are similar in appearance and composition to the deadly Portuguese man o’ war, but the two are actually unrelated. And the by-the-wind sailor isn’t known to kill people.
Both are colony creatures made up of zooids, but Jellywatch.org says they’re fundamentally different.
Although they [by-the-wind sailors] are blue-colored hydrozoans and float partly above the water like the Portuguese Man o’ War (Physalia), they are not especially closely related to it or other siphonophores. Even recent literature called them siphonophores, but the nearest Cnidarian relatives are the “Capitate” hydroids.
While by-the-wind sailors can sting their microscopic prey, they are not considered harmful to humans. And they should be handled with caution. The NOAA recommends avoiding all jellies when visiting the shore.
And when the sailors wash ashore, the remains can be unpleasant for those strolling the strand, according to the University of Washington:
When they wash ashore, these jellies quickly dry to the consistency of potato chips. During a mass stranding it’s like walking on a crunchy carpet.
Climate change is good for jellies
Mass strandings of by-the-wind sailors can be… massive!
At one point during strandings that occurred from 2015 to 2019, dead velvella covered a 620-mile (1,000-km) continuous stretch of West Coast beaches, the University of Washington reported.
That was the second of two periods of boom years for by-the-wind sailors UW researchers identified by analyzing 20 years of citizen reports. In looking over the data, they found the massive strandings corresponded to years of warmer weather.
The second period corresponds with the timing of the long-lasting marine heat wave known as the blob — also to blame for the largest seabird die-off of common murres, as well as mass die-offs of Cassin’s auklets, sea lions and baleen whales.
Warmer ocean temperatures result in larger populations of by-the-wind sailors and other jellies. Populations can reach into the trillions. The spring winds then push the floating hydroids onto shore.
According to Julia Parrish, a professor at the UW School of Aquatic and Fishery Sciences, by-the-wind sailor blooms like the one happening now are a marker of climate change:
…Our data really do suggest that in a warming world, we’re going to have more of these organisms — that is, the ecosystem itself is tipping in the direction of these jellies because they win in warmer conditions. A changing climate creates new winners and losers in every ecosystem. What’s scary is that we’re actually documenting that change.
Bottom line: Blue blob colony creatures are washing up by the millions on California beaches.
Read more: Big seaweed bloom headed to Florida and Caribbean
