Pyrosome

{{Short description|Family of tunicates}} {{Automatic taxobox | name = Pyrosomatidae | fossil_range = {{Fossil range|Neogene|Present}} | image = Pyrosoma atlanticum.JPG | image_caption = ''Pyrosoma atlanticum'' | parent_authority = Jones, 1848<ref>{{Catalogue of Life|id=B6LN9|title=Pyrosomatida|access-date=29 September 2024}}</ref> | taxon = Pyrosomatidae | authority = Lahille, 1888 | subdivision_ref = <ref name=WoRMS-family/> | subdivision_ranks = Genera | subdivision = *''Pyrosoma'' Péron, 1804<ref name=WoRMS-genus>{{cite taxon |WoRMS|id=137224 |title=''Pyrosoma'' Péron, 1804 |access-date=20 September 2024}}</ref> *''Pyrosomella'' van Soest, 1979 *''Pyrostremma'' Garstang, 1929 }}

'''Pyrosomes''' are free-floating colonial tunicates in family '''Pyrosomatidae'''. Pyrosomes consist of colonies of small zooids. There are three genera, ''Pyrosoma'', ''Pyrosomella'' and ''Pyrostremma'', and eight species.<ref name="WoRMS-family3">{{cite taxon|WoRMS|title=Pyrosomatidae Lahille, 1888|id=137216|access-date=29 September 2024}}</ref><ref name="Lilly20233">{{cite journal |last1=Lilly |first1=Laura E. |last2=Suthers |first2=Iain M. |last3=Everett |first3=Jason D. |last4=Richardson |first4=Anthony J. |year=2023 |title=A global review of pyrosomes: Shedding light on the ocean's elusive gelatinous "fire-bodies". |journal=Limnol. Oceanogr. Lett. |volume=8 |issue=6 |pages=812–829 |bibcode=2023LimOL...8..812L |doi=10.1002/lol2.10350 |doi-access=free}}</ref> They usually live in the upper layers of the open ocean in warm seas, although some may be found at greater depths.<ref name="Lilly20233"/> Pyrosomes exhibit bioluminescence,<ref name=":3">{{Cite journal |last1=Bowlby |first1=Mark R |last2=Bowlby |first2=Mark R. |last3=Widder |first3=Edith A. |last4=Case |first4=James F. |date=1990-12-01 |title=Patterns of Stimulated Bioluminescence in Two Pyrosomes (Tunicata: Pyrosomatidae) |url=https://www.biodiversitylibrary.org/part/24992 |journal=The Biological Bulletin |volume=179 |issue=3 |pages=340––350 |doi=10.2307/1542326|jstor=1542326 |pmid=29314963 }}</ref> and the name ''Pyrosoma'' derives from the Greek words ''pyro'', meaning "fire", and ''soma'', meaning "body".<ref>{{Cite journal |last1=Lilly |first1=Laura E. |last2=Suthers |first2=Iain M. |last3=Everett |first3=Jason D. |last4=Richardson |first4=Anthony J. |date=2023 |title=A global review of pyrosomes: Shedding light on the ocean's elusive gelatinous "fire-bodies" |journal=Limnology and Oceanography Letters |language=en |volume=8 |issue=6 |pages=812–829 |doi=10.1002/lol2.10350 |bibcode=2023LimOL...8..812L |issn=2378-2242|doi-access=free }}</ref> Pyrosomes are hermaphroditic and reproduce via a two-part process.<ref name="journals.uchicago.edu">{{Cite journal |last1=Piette |first1=Jacques |last2=Lemaire |first2=Patrick |date=June 2015 |title=Thaliaceans, The Neglected Pelagic Relatives of Ascidians: A Developmental and Evolutionary Enigma |url=https://www.journals.uchicago.edu/doi/abs/10.1086/681440?journalCode=qrb |journal=The Quarterly Review of Biology |volume=90 |issue=2 |pages=117–145 |doi=10.1086/681440 |pmid=26285352 |issn=0033-5770|url-access=subscription }}</ref> They have the ability to create massive blooms that may affect pelagic food webs.<ref name=":0">{{Cite journal |last1=Lyle |first1=Joanna T |last2=Cowen |first2=Robert K |last3=Sponaugle |first3=Su |last4=Sutherland |first4=Kelly R |date=2022-03-01 |title=Fine-scale vertical distribution and diel migrations of Pyrosoma atlanticum in the northern California Current |url=https://academic.oup.com/plankt/article/44/2/288/6535027?login=true |journal=Journal of Plankton Research |volume=44 |issue=2 |pages=288–302 |doi=10.1093/plankt/fbac006 |issn=0142-7873|url-access=subscription }}</ref>

== Description == Pyrosomes are commonly called "sea pickles", due to their tube-like gelatinous structure. Other nicknames include "sea worms", "sea squirts", "fire bodies", and "cockroaches of the sea".<ref name="NatGeo">{{cite news |last=Guo |first=Demi |date=February 20, 2019 |title=See the giant 'sea worm' filmed off the coast of New Zealand |url=https://www.nationalgeographic.com/animals/2019/02/giant-sea-worm-pyrosome-sighted-new-zealand/ |url-status=dead |archive-url=https://web.archive.org/web/20190220232656/https://www.nationalgeographic.com/animals/2019/02/giant-sea-worm-pyrosome-sighted-new-zealand/ |archive-date=February 20, 2019 |work=National Geographic}}</ref>

Each zooid opens both to the inside and outside of the "tube". The zooids draw in ocean water from the outside into their internal filtering mesh called the branchial basket, extracting the microscopic plant cells on which it feeds, and then expelling the filtered water to the inside of the colony's cylinder.<ref name="Atlantic">{{cite news |last=Garber |first=Megan |date=August 2, 2013 |title=12 Reasons Pyrosomes Are My New Favorite Terrifying Sea Creatures |url=https://www.theatlantic.com/technology/archive/2013/08/12-reasons-pyrosomes-are-my-new-favorite-terrifying-sea-creatures/278316/ |work=The Atlantic}}</ref><ref name="NatGeo" />

Pyrosomes are planktonic, which means their movements are largely controlled by currents, tides, and waves in the oceans. On a smaller scale, however, each colony can move itself slowly by the process of jet propulsion, created by the coordinated beating of cilia in the branchial baskets of all the zooids, which also create feeding currents.<ref>{{Cite web |date=2019-02-20 |title=See the giant 'sea worm' filmed off the coast of New Zealand |website=National Geographic Society |url=https://www.nationalgeographic.com/animals/2019/02/giant-sea-worm-pyrosome-sighted-new-zealand/ |access-date=2025-03-27 |archive-url=https://web.archive.org/web/20190220232656/https://www.nationalgeographic.com/animals/2019/02/giant-sea-worm-pyrosome-sighted-new-zealand/ |archive-date=20 February 2019 }}</ref>

Pyrosomes are brightly bioluminescent, flashing a pale blue-green light that can be seen for many tens of metres. Pyrosomes are closely related to salps, and are sometimes called "fire salps". Sailors on the ocean occasionally observe calm seas containing many pyrosomes, all luminescing on a dark night.<ref name="Atlantic" /><ref name="NatGeo" />

Pyrosomes feed through filtration and they are among the most efficient filter feeders of any zooplankton species. These colonial tunicates also are known to provide a source of shelter, food, and settlement from other deep sea organisms. They are also known to play a role in the marine Carbon cycle, as dead colonies sink to the sea floor to be consumed as food by other animals.<ref>{{Cite web |title=Pyrosomes - enigmatic marine inhabitants with an important role in the Cabo Verde ecosystem |url=https://www.geomar.de/en/news/article/pyrosomes-enigmatic-marine-inhabitants-with-an-important-role-in-the-cabo-verde-ecosystem |access-date=2025-03-27 |website=www.geomar.de |language=en-US}}</ref>

== Anatomy and morphology == thumb|Drawing of a pyrosome. Clearly shows the individual zooids that appear as small bumps on the surface of the tubular structure. A single individual of a pyrosome colony is referred to as an ascidiozooid, or zooid. A pyrosome colony contains many zooids which form a gelatinous tube, the walls of which range from 0.2 - 2.0 cm.<ref name=":03">{{Cite book |last1=Metcalf |first1=Maynard Mayo |url=https://books.google.com/books?id=WbIv6w--YBkC&dq=pyrosoma&pg=PA193 |title=Pyrosoma.--: A Taxonomic Study Based Upon the Collections of the United States Bureau of Fisheries and the United States National Museum |last2=Hopkins |first2=Hoyt Stilson |date=1919 |publisher=U.S. Government Printing Office |isbn=978-0-598-37021-1 |language=en}}</ref>

The zooids that make up a pyrosome are typically only a few mm long. Colonies of these zooids, which are bound together by a notochord and shared tissue, form a tube-like, hollow structure that is typically between 1 inch and 2 feet in length. However, giant pyrosomes can reach up to 60 feet in length, with a hollow opening up to 6 feet (2 meters) wide.<ref>{{Cite web |last=Perez |first=Jennifer |date=2024-06-14 |title=The Mysterious World of Pyrosomes |url=https://oceanconservancy.org/blog/2024/06/14/the-mysterious-world-of-pyrosomes/ |access-date=2025-03-12 |website=Ocean Conservancy |language=en}}</ref> There have been some instances in which deep sea scientists have swum inside of a giant pyrosome's hollow body.<ref name=":04">{{Cite web |last=Helm |first=R. R. |date=2013-08-01 |title=The 60 foot long jet powered animal you've probably never heard of {{!}} Deep Sea News |url=https://deepseanews.com/2013/08/the-60-foot-long-jet-powered-animal-youve-probably-never-heard-of/ |access-date=2025-03-12 |website=deepseanews.com |language=en-US}}</ref>

Pyrosomes are transparent and gelatinous, with a slimy yet bumpy texture.<ref>{{Cite web |last=Fisheries |first=NOAA |date=2022-05-10 |title=Pyrosomes {{!}} NOAA Fisheries |url=https://www.fisheries.noaa.gov/science-blog/pyrosomes#:~:text=Pyrosomes%20are%20pelagic%20Tunicates,%20which,zooids%20are%20tightly%20packed%20together. |access-date=2025-03-12 |website=NOAA |language=en}}</ref> Zooids appear as small bumps on the colony, although the colony appears nearly smooth with perforated holes for each zooid on the inside.<ref>{{Cite web |last=Garber |first=Megan |date=2013-08-02 |title=12 Reasons Pyrosomes Are My New Favorite Terrifying Sea Creatures |url=https://www.theatlantic.com/technology/archive/2013/08/12-reasons-pyrosomes-are-my-new-favorite-terrifying-sea-creatures/278316/ |access-date=2025-04-02 |website=The Atlantic |language=en}}</ref> Each zooid has a stomach that can be seen through the transparent body of the colony. These stomachs have been compared to "wire baskets".<ref name=":04" />

==Bioluminescence== Although many planktonic organisms are bioluminescent, pyrosome bioluminescence is unique due to the nature and origins of its brilliant light emissions. Pyrosomes often exhibit waves of light passing back and forth through the colony, as each individual zooid detects light and then emits light in response.<ref name=":3" /> These waves of bioluminescence are most likely a response to photic stimulation as opposed to nerve impulses, though zooids have also been observed emitting light in response to mechanical stimulation.<ref name=":4">{{Cite journal |last1=Mackie |first1=G. O. |last2=Bone |first2=Q. |date=1978 |title=Luminescence and Associated Effector Activity in Pyrosoma (Tunicata: Pyrosomida) |url=https://www.jstor.org/stable/77343 |journal=Proceedings of the Royal Society of London. Series B, Biological Sciences |volume=202 |issue=1149 |pages=483–495 |doi=10.1098/rspb.1978.0081 |jstor=77343 |bibcode=1978RSPSB.202..483M |issn=0080-4649|url-access=subscription }}</ref> Pyrosomes may use bioluminescence to signal danger or otherwise communicate with individuals of the same or nearby colonies.<ref name=":4" />

Each zooid contains a pair of light organs located near the outside of the tunic, or the protective outer layer, whose cells are full of organelles containing intracellular, bioluminescent bacteria.<ref name=":4" /> While an exact taxonomic identification of this bacteria has not been made, the morphology of the double-membrane enclosed organelle and the bacteria itself is similar to that of other extracellular bioluminescent bacterial symbionts as well as other intracellular bacterial symbionts.<ref name=":4" /><ref name=":5">{{Cite journal |last1=Berger |first1=Alexis |last2=Blackwelder |first2=Patricia |last3=Frank |first3=Tamara |last4=Sutton |first4=Tracey T. |last5=Pruzinsky |first5=Nina M. |last6=Slayden |first6=Natalie |last7=Lopez |first7=Jose V. |date=2021-02-03 |title=Microscopic and Genetic Characterization of Bacterial Symbionts With Bioluminescent Potential in Pyrosoma atlanticum |journal=Frontiers in Marine Science |language=English |volume=8 |doi=10.3389/fmars.2021.606818 |doi-access=free |bibcode=2021FrMaS...806818B |issn=2296-7745}}</ref> These bacteria live within the host cells, which assumably control bacterial light emissions, a phenomenon rarely seen in other bioluminescent marine organisms.<ref name=":4" /> Uncertainties about the overall control mechanisms and evolutionary relationship between ''Pyrosoma'' and their specialized symbionts constitute a research gap and are continuing to be studied.<ref name=":4" /><ref name=":5" />

==Reproduction== Pyrosomes are hermaphroditic and have a two-part life cycle. In the first stage, a fertilized egg develops into a cyathozooid.<ref name="journals.uchicago.edu"/> After this, the cyathazooid produces a tetrazooid, or four ascidizooids, via budding.<ref name=":03"/> Colonies are able to self fertilize from one end of the tube to the other, as the closed end of the lobe is protandrous, meaning that male gametes are produced before female, while the open end is protogynous, with the female gametes maturing before the male.<ref name=":12">{{Cite journal |last=van Soest |first=R.W.M. |date=1981-01-01 |title=A monograph of the order Pyrosomatida (Tunicata, Thaliacea) |url=https://academic.oup.com/plankt/article-abstract/3/4/603/1476061?redirectedFrom=fulltext |journal=Journal of Plankton Research |volume=3 |issue=4 |pages=603–631 |doi=10.1093/plankt/3.4.603 |issn=0142-7873|url-access=subscription }}</ref>

== Food chain niche == Pyrosomes are filter feeding tunicates that consume small particles like phytoplankton and detrital matter. That being said, their predator to prey mass ratio is very large at almost 50 million : 1.<ref name="Lilly20233"/> Predator to prey mass ratio refers to the ratio between the mass of the predator organism vs. the mass of the prey organism. In this instance, the pyrosomes are generally 50 million times larger in mass than the prey they consume. Generally, pyrosomes graze a wide variety of microbes with most research surrounding larger eukaryotic phytoplankton but pyrosome feeding on smaller heterotrophic microbes is not well understood.<ref name=":32">{{Cite journal |last1=Thompson |first1=Anne W |last2=Ward |first2=Anna C |last3=Sweeney |first3=Carey P |last4=Sutherland |first4=Kelly R |date=2021-12-01 |title=Host-specific symbioses and the microbial prey of a pelagic tunicate ( Pyrosoma atlanticum ) |journal=ISME Communications |language=en |volume=1 |issue=1 |doi=10.1038/s43705-021-00007-1 |issn=2730-6151 |pmc=9723572 |pmid=36721065}}</ref>

Pyrosomes are essential members of the food chain on multiple fronts. Pyrosomes feed on large numbers of microbes, fall after death, vertically migrate while producing marine snow, and are prey for marine mammals, seabirds, turtles, or fish.<ref name=":32" /> With these comes contribution to the marine carbon cycle. About 35% of the dry weight of Pyrosomes is carbon which is high for gelatinous organisms.<ref>{{Cite journal |last1=Lebrato |first1=M. |last2=Jones |first2=D. O. B. |date=2009 |title=Mass deposition event of Pyrosoma atlanticum carcasses off Ivory Coast (West Africa) |url=https://aslopubs.onlinelibrary.wiley.com/doi/10.4319/lo.2009.54.4.1197 |journal=Limnology and Oceanography |language=en |volume=54 |issue=4 |pages=1197–1209 |doi=10.4319/lo.2009.54.4.1197 |doi-access=free|issn=1939-5590|url-access=subscription }}</ref> During their daily vertical migration of up to 900m or falls after death, Pyrosomes are prey to at least 62 pelagic organisms (like turtles and sea lions) and at least 33 benthic organisms (like sea urchins and crabs). Therefore, their role as contributors to the marine carbon cycle is likely very essential.<ref>{{Cite journal |last1=Henschke |first1=Natasha |last2=Pakhomov |first2=Evgeny A. |last3=Kwong |first3=Lian E. |last4=Everett |first4=Jason D. |last5=Laiolo |first5=Leonardo |last6=Coghlan |first6=Amy R. |last7=Suthers |first7=Iain M. |date=2019 |title=Large Vertical Migrations of Play an Important Role in Active Carbon Transport |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2018JG004918 |journal=Journal of Geophysical Research: Biogeosciences |language=en |volume=124 |issue=5 |pages=1056–1070 |doi=10.1029/2018JG004918 |issn=2169-8961|hdl=10453/139295 |hdl-access=free }}</ref>

== Taxonomy == thumb|''Pyrosoma atlanticum'' by a tide pool in California

According to the World Register of Marine Species, the family is divided into two subfamilies and three genera, containing eight species.<ref name="WoRMS-family">{{cite taxon|WoRMS|title=Pyrosomatidae Lahille, 1888|id=137216|access-date=29 September 2024}}</ref>

* Subfamily Pyrosomatinae Lahille, 1888 ** Genus ''Pyrosoma'' Péron, 1804 *** ''Pyrosoma aherniosum'' Seeliger, 1895 *** ''Pyrosoma atlanticum'' Péron, 1804 *** ''Pyrosoma godeauxi'' van Soest, 1981 *** ''Pyrosoma ovatum'' Neumann, 1909 ** Genus ''Pyrosomella'' van Soest, 1979 *** ''Pyrosomella operculata'' (Neumann, 1909) *** ''Pyrosomella verticillata'' (Neumann, 1909) * Subfamily Pyrostremmatinae van Soest, 1979 ** Genus ''Pyrostremma'' Garstang, 1929 *** ''Pyrostremma agassizi'' (Ritter & Byxbee, 1905) *** ''Pyrostremma spinosum'' (Herdman, 1888)

The three genera of pyrosomes, ''Pyrostremma, Pyrosomella,'' and ''Pyrosoma,'' have morphological similarities and differences. Most pyrosome colonies are finger-shaped, but there are two exceptions in the ''Pyrosoma'' genera; ''P. godeauxi'' and ''P. ovatum'' have a more globular appearance. Generally, pyrosomes have limp tests, or outer coverings. However, in some cases, ''Pyrosoma'' have tough, elastic tests. Each genera has test projections, those of ''Pyrostremma'' being triangular and spiny, ''Pyrosomella'' smooth, and ''Pyrosoma'' long and blunt.<ref name=":12"/>

A colonial sphincter, or diaphragm, is present in ''Pyrosomella'' and ''Pyrosoma'', but is absent in ''Pyrostremma''. While ''Pyrostremma'' species have a slit-like arial sphincter, ''Pyrosoma'' and ''Pyrosomella'' have circular sphincters. The orientation of zooids differs between genera as well. In ''Pyrostremma'', new zooids are added in a swirled pattern; ''Pyrosomella'' form zooids in parallel rows; ''Pyrosoma'' add zooids in a dense, random arrangement.<ref name=":12" /> Pyrosomes can also develop into some of the longest animals in the ocean.<ref name="Lilly20233"/> For example, the ''Pyrostremma spinosum,'' can fully extend up to 3 meters and grow up to 20 meters in length. {{Citation needed|date=March 2025}}

In regards to the three genera of pyrosomes, the cellular components of their tunic have been documented.<ref>{{Cite journal |last1=Hirose |first1=Euichi |last2=Ohshima |first2=Chie |last3=Nishikawa |first3=Jun |date=November 2001 |title=Tunic cells in pyrosomes (Thaliacea, Urochordata ): cell morphology, distribution, and motility |url=https://onlinelibrary.wiley.com/doi/10.1111/j.1744-7410.2001.tb00047.x |journal=Invertebrate Biology |language=en |volume=120 |issue=4 |pages=386–393 |doi=10.1111/j.1744-7410.2001.tb00047.x |bibcode=2001InvBi.120..386H |issn=1077-8306|url-access=subscription }}</ref> Multiple different cellular types have been found to be distributed in the tunic of ''Pyrosome atlanticum, Pyrosomella verticillata, and Pyrostremma spinosum.'' These cell types include Tunic amebocytes, which are found to be motile and shaped asymmetrically. They are also found to either contain granules or phagosomes within them. Another cell type is known as Spherical Tunic cells, in which contain spherical vesicle that often contain eosinophilic and acidic substances. Net cells form a net in which the cell's elongated filopodia connect with each other, forming a network. This network maintains a tension in order to reinforce the colony shape and support the cell's cloacal cavity. Multicellular cords also exist between the tunic cells and the zooids, and are known as test fibers. They are hypothesized to maintain and control muscle contractions of the zooids.

== Geographic distribution == Pyrosomes are globally distributed organisms, with recorded sightings in every ocean, with the exception of the Arctic Ocean, and are typically latitudinally confined within 50°N and 50°S.<ref name=":12" /><ref name=":1">{{Cite journal |last1=O'Loughlin |first1=Jessica H. |last2=Bernard |first2=Kim S. |last3=Daly |first3=Elizabeth A. |last4=Zeman |first4=Samantha |last5=Fisher |first5=Jennifer L. |last6=Brodeur |first6=Richard D. |last7=Hurst |first7=Thomas P. |date=2020-10-01 |title=Implications of Pyrosoma atlanticum range expansion on phytoplankton standing stocks in the Northern California Current |url=https://linkinghub.elsevier.com/retrieve/pii/S0079661120301634 |journal=Progress in Oceanography |volume=188 |article-number=102424 |doi=10.1016/j.pocean.2020.102424 |issn=0079-6611|url-access=subscription }}</ref> However, some pyrosome species have been shown to expand their geographic range in response to increasing ocean temperatures, which has unknown implications for the already existing ecosystems.<ref name=":1" /> Additionally, there is some evidence pointing towards geographic distribution changes of pyrosome colonies in relation to changes in the season.<ref name=":0" />

In relation to vertical distribution and diel vertical migration, pyrosomes have been shown to travel between 20 meters to greater than 700 meters in the water column.<ref name="Lilly20233" /> Although most pyrosome sightings occur relatively near the surface at night, there is still wide intraspecies variation in migration distance, ranging from travel distances of 20 meters to more than 500 meters per day.<ref name="Lilly20233" /><ref name=":0" />

==Blooms== Pyrosomes have the ability to create enormous blooms, which are rapid and substantial increases in population. Some scientists hypothesize that the presence of a food fall can contribute to these blooms.<ref name=":2">{{Cite web |last1=Archer |first1=Stephanie K. |last2=Kahn |first2=Amanda S. |last3=Leys |first3=Sally P. |last4=Norgard |first4=Tammy |last5=Girard |first5=Fanny |last6=Du Preez |first6=Cherisse |last7=Dunham |first7=Anya |date=2018-04-01 |title=Pyrosome consumption by benthic organisms during blooms in the northeast Pacific and Gulf of Mexico |url=https://era.library.ualberta.ca/items/3b83fde1-24c8-49d6-a890-553e1ecc6f32 |access-date=2025-04-01 |website=ERA |language=en}}</ref> Since pyrosomes are food-limited organisms, they may take advantage of these circumstances to increase reproduction.<ref name=":2" />

Past evidence suggests that sustained, multi-year blooms are not environmentally favorable, but blooms may become increasingly prevalent as warming water temperatures globally can provide favorable conditions for recurring pyrosome blooms.<ref>Miller, Rebecca R.; Wells, Brian K.; Brodeur, Richard D.; Santora, Jarrod A.; Auth, Toby D.; Sakuma, Keith M.; Field, John C. (December 2019). "[https://calcofi.org/downloads/publications/calcofireports/v60/Vol60-CalCOFIReports2019.pdf Distribution of pelagic thaliaceans, Thetys vagina and Pyrosoma atlanticum, during a period of mass occurrence within the California Current]" (PDF). ''California Cooperative Oceanic Fisheries Investigations Report''. '''60''' (1): 142 – via CalCOFI.</ref> In 2017, pyrosomes were observed to have spread in unprecedented numbers along the Pacific coast of North America as far north as Alaska. The causes remain unknown, but one hypothesis is that this bloom may have resulted in part from unusually warm water along the coast over several preceding years. Also, weak upwelling off the coast of northern California creates an ideal environment for blooms.<ref name=":0" /> Scientists were concerned that should there be a massive die-off of the pyrosomes, it could create a huge dead zone as the decomposition of their bodies could consume much of the oxygen dissolved in the surrounding seawater.<ref name="blobs">{{Cite web |date=22 June 2017 |title=Blob-like intruders infesting pacific coast |url=http://www.newser.com/story/244630/blob-like-intruders-infesting-pacific-coast.html}}</ref><ref name="blob2">{{Cite web |date=22 June 2017 |title=Newsweek: Mysterious Sea Pickles invading West Coast in bizarre bloom |url=http://www.newsweek.com/mysterious-sea-pickles-invading-west-coast-bizarre-bloom-628338 |website=Newsweek}}</ref><ref>{{cite web |url=http://www.opb.org/news/article/massive-bloom-of-pickle-shaped-sea-creatures-fills-the-pacific/ |title=''Massive Bloom Of Pickle-Shaped Sea Creatures Fills The Pacific'' |publisher=Oregon Public Radio |access-date=November 17, 2017}}</ref>

Scientists have observed that large blooms can hurt pelagic food webs, for an increased population leads to increased grazing pressure, ultimately affecting the transfer of energy in these environments.<ref name=":0" /> Through this excessive phytoplankton grazing, the amount of food available for other organisms to feed on decreases. However, pyrosomes contain a lot of energy and have been reported being consumed by pelagic fish and cetaceans; there have also been jelly-falls containing pyrosomes, suggesting that these organisms can provide carbon for benthic organisms to consume.<ref name=":0" />

==References== {{Reflist}}

== Bibliography == *Bone, Q. editor (1998) The Biology of Pelagic Tunicates. Oxford University Press, Oxford. 340 pp.

==External links== {{Commons category|Pyrosoma}} *{{cite web |title=A 'sea pickle'? An animal that can grow to 60 feet long is washing up on the Oregon coast |date=1 Feb 2022 |author=Jordan Mendoza |website=USA Today |url=https://www.usatoday.com/story/news/nation/2022/02/01/sea-pickle-washing-up-oregon-beaches/9230497002/}} *[https://web.archive.org/web/20120216134956/http://www.mar-eco.no/mareco_news/2004/the_pyrosome_story Huge pyrosome captured in the North Atlantic - story and images] *[http://www.divebums.com/FishID/Pages/pyrosoma_atlanticum.html Images taken by divers off southern California] *[http://www.lifesci.ucsb.edu/~biolum/ The Bioluminescence Web Page] *[https://archive.nerdist.com/pyrosomes-are-the-borg-of-the-oceans/ Divers with huge southern hemisphere pyrosomes] *[http://www.cbc.ca/news/canada/british-columbia/tropical-sea-creatures-blooming-bc-1.4164883/ Millions of tropical sea creatures invade waters off B.C. coast] *[https://www.fisheries.noaa.gov/feature-story/researchers-investigate-explosion-number-pyrosomes-alaska/ Researchers Investigate Explosion in the Number of Pyrosomes off Alaska] * {{Cite web |title=The 60 foot long jet powered animal you've probably never heard of |author=R R Helm |date=1 August 2013 |publisher=Deep Sea News |url=http://deepseanews.com/2013/08/the-60-foot-long-jet-powered-animal-youve-probably-never-heard-of/ }}

Category:Pyrosomatidae