Invasion History

First Non-native North American Tidal Record: 1997
First Non-native West Coast Tidal Record: 1997
First Non-native East/Gulf Coast Tidal Record:

General Invasion History:

The colonial tunicate Botrylloides giganteus was first described from Senegal in 1949. In the 1980s, it was found in Brazil, over a limited range from Sao Paulo to Vittorio (Aron and Sole-Cava 1991, Rodrigues and da Rocha 1993, Da Rocha and Costa 2005). In 1997, a colonial tunicate, first identified as B. perspicuum, was found on the coast of southern California (Lambert and Lambert 2003). Recent morphological and genetic studies (in preparation) indicate that the Southern California form was conspecific with B. giganteus and with a colonial tunicate described from the Gulf of Taranto, Italy, B. pizoni (Brunetti and Mastrotaro 2012). It has also been identified in New Zealand (Riding et al. 2014, Ministry of Primary Studies 2015, Rocha et al. 2019). The native and introduced ranges of this tunicate are unresolved. 

North American Invasion History:

Invasion History on the West Coast:

Botrylloides giganteum was first collected in the Eastern Pacific in 1997 at the Naval Station in San Diego Bay, California. Since then, it has been collected at several sites in San Diego and Mission Bay and appears to have extended its range from the initial sites of collection in both locations (Lambert and Lambert 2003). In 2003, it was collected in Alamitos Bay and Huntington Harbor, south of Los Angeles (Ruiz et al., unpublished data) and in BahiáSan Quintín, on the Pacific Coast of Baja California in 2005 (Rodriguez and Ibarra-Obando 2008).

Invasion History Elsewhere in the World:

The native range of Botrylloides giganteus is unknown. The type locality was Senegal (Peres 1949, cited by (Aron and Sole-Cava 1991), but it was subsequently found on the Indian Ocean coast of South Africa and Mozambique (Millar 1955, Millar 1961, Millar 1963, cited by Monniot et al. 2001; Rocha et al. 2019). In Brazil, it was first found in 1986, and is known largely from artificial substrates, and is especially abundant in mussel cultures. It was not seen in previous surveys and is considered introduced and established in Brazil (da Rocha et al. 2009; Rocha et al. 2019; Oricchio et al. 2019). In 2014, B. giganteus was found in Whangarei Harbor, New Zealand (Riding et al. 2014; Rocha et al. 2019), and on Santa Cruz and Baltra Islands, in the Galapagos Archipelago, in 2015 (Lambert 2009; Rocha et al 2019).


Description

Botrylloides giganteus is a colonial tunicate. Colonial tunicates are communities of individuals, called zooids, which share a protective cellulose layer called a tunic. Each zooid is an individual, but they are such an intricate part of the colony that they cannot be separated from it. In fact, the zooids are connected to one another by a network of blood vessels and work together to make the colony function like a single animal.

The colonies of B. giganteus are 2-5 mm thick, translucent, and variable in size and shape, ranging from 30 to 150 mm in diameter. They can grow on algae or other debris. Botrylloides giganteus has linear systems of zooids, which are visible through the tunic. The colonies are red to orange or violet in color. The body walls of its zooids are very delicate and transparent and lack longitudinal or circular musculature. The oral siphon is round, with a smooth margin. There are 24 branchial tentacles in mature zooids. On the branchial sac there are 11-17 pairs (usually 14) of stigmata. The atrial siphon develops a languet, a tongue-like structure, which varies in shape and length. The esophagus is short and curved, and the stomach has 9-10 longitudinal folds. A mature zooid can have a single developing embryo. Description based on: Rodrigues and da Rocha 1993, and da Rocha and Costa 2005.

This tunicate, discovered in Southern California, was initially identified as B. perspicuum (1997, Lambert and Lambert 2003). Recent observations indicate that it is actually B. giganteus (Gretchen Lambert and Rosana da Rocha, personal communications). We are in the process of revising the morphological description and biogeographical history of this species (Rodriques and da Rocha 1993; da Rocha and Costa 2005; Rocha et al. 2019).


Taxonomy

Taxonomic Tree

Kingdom:   Animalia
Phylum:   Chordata
Subphylum:   Tunicata
Class:   Ascidiacea
Order:   Stolidobranchia
Family:   Styelidae
Genus:   Botrylloides
Species:   giganteus

Synonyms

Botryllus giganteus (Aron & Sole Cava, 1991)
Botrylloides niger var. giganteum (Pérès, 1949)
Botrylloides giganteum (Ryland, 2015)
Botrylloides pizoni (Brunetti and Mastrotaro, 2012)

Potentially Misidentified Species

Botrylloides conchyliatus
Rocha et al. 2919, new species, described from Queesland, Australia

Botrylloides leachii
Kott 1972, cited by Kott 1985

Botrylloides nigrum
Michaelson 1919, cited by Kott 1985

Botrylloides perspicuus

This tunicate was initially identified as Botrylloides perspicuum (1997, Lambert and Lambert 2003). Recent observations suggested that it is actually B. giganteum (Gretchen Lambert, Rosana da Rocha, personal communications, 2013–2015).



Botyrllus firmus
Monniot and Monniot 2001

Ecology

General:

Life History- A colonial (or compound) tunicate consists of many zooids, bearing most or all of the organs of a solitary tunicate, but modified to varying degrees for colonial life. Colonial tunicates of the genera Botrylloides have small zooids, usually not organized in systems, and fully embedded in a mass of tunic material. Each zooid has an oral siphon and an atrial canal, opening to a shared cloacal chamber. Water is pumped into the oral siphon, through finely meshed ciliated gills on the pharynx, where phytoplankton and detritus is filtered, and passed on mucus strings to the stomach and intestines. Excess waste is expelled in the outgoing atrial water (Van Name 1945; Barnes 1983). 
 
Colonial tunicates reproduce both asexually, by budding, and sexually, from fertilized eggs developing into larvae. Buds can form from the body wall of the zooid. Colonies vary in size and can range from small clusters of zooids to huge spreading masses. The zooids are hermaphroditic, with eggs and sperm being produced by a single individual. Eggs may be self-fertilized or fertilized by sperm from nearby animals, but many species have a partial block to self-fertilization. Eggs are internally fertilized, and embryos are incubated in a brood pouch. Once they are mature, fertilized eggs hatch into a tadpole larva with a muscular tail, notochord, eyespots, and a set of adhesive papillae. The lecithotrophic (non-feeding, yolk-dependent) larva swims briefly before settlement. Swimming periods are usually less than a day, and some larvae can settle immediately after release, but the larval period can be longer at lower temperatures. Once settled, the tail is absorbed, the gill basket expands, and the tunicate begins to feed by filtering (Van Name 1945; Barnes 1983). 

Food:

Phytoplankton

Consumers:

fishes, crabs

Trophic Status:

Suspension Feeder

SusFed

Habitats

General HabitatRockyNone
General HabitatCoral reefNone
General HabitatMarinas & DocksNone
Salinity RangePolyhaline18-30 PSU
Salinity RangeEuhaline30-40 PSU
Tidal RangeSubtidalNone
Tidal RangeLow IntertidalNone
Vertical HabitatEpibenthicNone

Life History


Tolerances and Life History Parameters

Broad Temperature RangeNoneWarm temperate-Tropical
Broad Salinity RangeNonePolyhaline-Euhaline

General Impacts

Competition: The colonial tunicate Botrylloides giganteus (then identified as B. perspicuum) covered extensive areas crowding out other species. This was seen in San Diego Bay in 1997 (Lambert and Lambert 2003).


Regional Impacts

NEP-VIPt. Conception to Southern Baja CaliforniaEcological ImpactCompetition
The colonial tunicate Botrylloides giganteum is a recent invader of two locations in southern California, in Mission Bay and San Diego Bay. From 1994-2000 strong competition was noted at some locations where the tunicate grew over extensive areas (100% cover) (Lambert and Lambert 2003).
P020San Diego BayEcological ImpactCompetition
The colonial tunicate Botrylloides giganteum is a recent invader of San Diego Bay. At one location (24th street), in 1997, it covered extensive areas up to 100% cover, indicating strong competitive ability (Lambert and Lambert 2003).
P030Mission BayEcological ImpactCompetition
The colonial tunicate Botrylloides giganteum is a recent invader of Mission Bay. Strong competition was noted at some locations where the tunicate grew over extensive areas (100% cover) (Lambert and Lambert 2003).
CACaliforniaEcological ImpactCompetition
The colonial tunicate Botrylloides giganteum is a recent invader of San Diego Bay. At one location (24th street), in 1997, it covered extensive areas up to 100% cover, indicating strong competitive ability (Lambert and Lambert 2003)., The colonial tunicate Botrylloides giganteum is a recent invader of Mission Bay. Strong competition was noted at some locations where the tunicate grew over extensive areas (100% cover) (Lambert and Lambert 2003).

Regional Distribution Map

Bioregion Region Name Year Invasion Status Population Status
P065 _CDA_P065 (Santa Barbara Channel) 2020 Def Estab
P060 Santa Monica Bay 2013 Def Estab
P062 _CDA_P062 (Calleguas) 2013 Def Estab
P064 _CDA_P064 (Ventura) 2013 Def Estab
P050 San Pedro Bay 2003 Def Estab
P030 Mission Bay 1998 Def Estab
P020 San Diego Bay 1997 Def Estab
NEP-VI Pt. Conception to Southern Baja California 1997 Def Estab

Occurrence Map

OCC_ID Author Year Date Locality Status Latitude Longitude
697153 ISS 2000-2002 Survey Data 2000 2000-11-08 Port Hueneme Epifaunal 04 Def 34.1468 -119.2119
697235 Maloney et al. 2007 2005 2005-04-27 Kelco Dock Def 32.6927 -117.1470
697772 Maloney et al. 2007 2005 2005-04-26 San Diego Bay Commercial Fishing Fleet Def 32.7109 -117.1739
697779 ISS 2000-2002 Survey Data 2001 2001-10-09 San Diego Bay Commercial Fishing Fleet Def 32.7109 -117.1739
697795 ISS 2000-2002 Survey Data 2001 2001-08-15 Newport Beach Epifaunal 05 Def 33.6212 -117.9364
698145 ISS 2000-2002 Survey Data 2001 2001-07-11 Marina Del Rey Epifaunal 04 Def 33.9760 -118.4460
698556 Cohen et al. 2002 (So Cal Exotics RAS); Lambert and Lambert 2003 2000 2000-08-28 Seaforth Landing Def 32.7644 -117.2381
698593 ISS 2000-2002 Survey Data 2001 2001-07-11 Marina Del Rey Epifaunal 02 Def 33.9828 -118.4467
698630 ISS 2000-2002 Survey Data 2001 2001-08-16 Long Beach Epifaunal 06 Def 33.7697 -118.2283
698696 ISS 2000-2002 Survey Data 2001 2001-10-09 Marine Terminal (Paco) Def 32.6584 -117.1191
698697 Introduced Species Study 2011 2011-05-03 Marine Terminal (Paco) Def 32.6584 -117.1191
698698 Maloney et al. 2007 2005 2005-04-27 Marine Terminal (Paco) Def 32.6584 -117.1191
698782 Maloney et al. 2007 2005 2005-06-28 Navy - 28th St. Def 32.6836 -117.1311
698830 ISS 2000-2002 Survey Data 2001 2001-08-14 Oceanside Epifaunal 04 Def 33.2087 -117.3949
698847 Introduced Species Study 2006 2006-09-13 Guest Dock Def 33.2091 -117.3947
698950 ISS 2000-2002 Survey Data 2001 2001-07-10 Channel Islands Harbor Epifaunal 06 Def 34.1757 -119.2234
698974 Introduced Species Study 2006 2006-09-12 Dana Inn Marina Def 32.7671 -117.2362
699162 ISS 2000-2002 Survey Data 2001 2001-07-10 Channel Islands Harbor Epifaunal 02 Def 34.1811 -119.2319
699174 ISS 2000-2002 Survey Data 2001 2001-07-11 Marina Del Rey Epifaunal 03 Def 33.9703 -118.4494
699591 ISS 2000-2002 Survey Data 2001 2001-08-16 Long Beach Epifaunal 02 Def 33.7477 -118.1975
699737 Introduced Species Study 2011 2011-05-04 Seaforth Def 32.7621 -117.2365
699811 Maloney et al. 2007 2005 2005-04-27 Coronado Wharf Def 32.6992 -117.1684
699816 ISS 2000-2002 Survey Data 2001 2001-10-09 Coronado Wharf Def 32.6992 -117.1684
700345 ISS 2000-2002 Survey Data 2001 2001-08-16 Long Beach Epifaunal 03 Def 33.7628 -118.2145
700406 Introduced Species Study 2006 2006-08-24 Near Huntington Launch Ramp Def 33.7279 -118.0786
700447 ISS 2000-2002 Survey Data 2001 2001-08-16 Long Beach Epifaunal 04 Def 33.7709 -118.2113
700452 ISS 2000-2002 Survey Data 2001 2001-07-10 Channel Islands Harbor Epifaunal 01 Def 34.1742 -119.2271
700552 ISS 2000-2002 Survey Data 2001 2001-07-10 Channel Islands Harbor Epifaunal 05 Def 34.1739 -119.2236
700857 Maloney et al. 2007 2005 2005-04-26 Harbor Island Marina Def 32.7266 -117.2128
700859 ISS 2000-2002 Survey Data 2001 2001-10-10 Harbor Island Marina Def 32.7266 -117.2128
701035 ISS 2000-2002 Survey Data 2001 2001-07-09 Santa Barbara Epifaunal 01 Def 34.4045 -119.6920
701854 Introduced Species Study 2006 2006-08-21 APL Terminal Def 33.7348 -118.2479
702024 Introduced Species Study 2011 2011-05-03 America's Cup Harbor Def 32.7239 -117.2240
702060 ISS 2000-2002 Survey Data 2001 2001-08-16 Long Beach Epifaunal 05 Def 33.7766 -118.2107
702184 ISS 2000-2002 Survey Data 2001 2001-07-09 Santa Barbara Epifaunal 03 Def 34.4067 -119.6889
703079 Maloney et al. 2007 2005 2005-04-26 San Diego Bay Cruise Ship Terminal Def 32.7168 -117.1759
703080 ISS 2000-2002 Survey Data 2001 2001-10-09 San Diego Bay Cruise Ship Terminal Def 32.7168 -117.1759
703096 ISS 2000-2002 Survey Data 2000 2000-11-08 Port Hueneme Epifaunal 07 Def 34.1477 -119.2042
703113 Maloney et al. 2007 2005 2005-04-26 Switzer Creek Def 32.7043 -117.1615
703201 Maloney et al. 2007 2005 2005-06-28 Ballast Point Def 32.6861 -117.2348
703492 ISS 2000-2002 Survey Data 2001 2001-08-15 Newport Beach Epifaunal 06 Def 33.6154 -117.9022
703523 Cohen et al. 2002 (So Cal Exotics RAS) 2000 2000-08-26 Shelter Island Def 32.7100 -117.2342
704462 ISS 2000-2002 Survey Data 2001 2001-07-12 Huntington Harbour Epifaunal 01 Def 33.7128 -118.0543
704652 Maloney et al. 2007 2005 2005-06-28 Navy - Carrier Base Def 32.7062 -117.1886
713599 Lambert and Lambert 2003 1997 24th Street Boat Launch, San Diego Bay Def 32.6495 -117.1108
713600 Lambert and Lambert 2003 1998 Shelter Island, San Diego Bay Def 32.7100 -117.2342
713601 de Rivera et al. 2005 2003 Chula Vista Marina, San Diego Def 32.6244 -117.1038
713602 de Rivera et al. 2005 2003 Dana Marina Def 32.7675 -117.2365
713603 de Rivera et al. 2005 2003 Seaforth Marina, San Diego Def 32.7630 -117.2373
713604 Ruiz et al., unpublished data 2003 Alamitos Bay Marina, Long Beach Def 33.7497 -118.1172
713605 Ruiz et al., unpublished data 2003 Pete's Landing Marina, Huntington Harbour Def 33.4355 -118.0451
756508 Lambert and Lambert 2003 1998 Seaforth Landing Def 32.7644 -117.2381
756509 Lambert and Lambert 2003 1998 24th Street Boat Launch, San Diego Bay Def 32.6495 -117.1108
769409 Ruiz et al., 2021b 2018 2018-08-10 Alamitos Bay Marina, San Pedro Bay, California, USA Def 33.7494 -118.1154

References

Aron, Simone; Sole-Cava, Antonio (1991) Genetic evaluation of the taxonomic status of two varieties of the cosmopolitan Botryllus niger (Ascidiaceae: Botryllidae), Biochemical Systematics and Ecology 19(4): 271-276

Baker, H. R. (1984) Diversity and zoogeography of marine Tubificidae (Annelida, Oligochaeta), with notes on variation in widespread species, Hydrobiologia 115: 191-196

Barnes, Robert D. (1983) Invertebrate Zoology, Saunders, Philadelphia. Pp. 883

Bastida-Zavala, Rolando; de León-González, Jesús Ángel; Carballo Cenizo, José Luis; Moreno-Dávila, Betzabé (2014) [Aquatic Invasive Species in Mexico], Comisión Nacional para el Conocimiento y Uso de la Biodiversidad, <missing place>. Pp. 317-336

Blanco, Andreu; Beger, Maria; Olabarria, Celia (2021) First confirmed occurrence of Codium fragile (Suringar) Hariot in the Iberian Peninsula coast of Portugal, BioInvasions Records 10: <missing location>

Brunetti. R.; Mastrototaro, F. (2012) Botrylloides pizoni, a new species of Botryllinae (Ascidiacea) from the Mediterranean Sea, Zootaxa 3258: 28-36

California Department of Fish and Wildlife (2014) Introduced Aquatic Species in California Bays and Harbors, 2011 Survey, California Department of Fish and Wildlife, Sacramento CA. Pp. 1-36

da Rocha, Rosana M.; Costa, Luciana (2005) Ascidians (Urochordata: Ascidiacea) from Arriaal do Cabo, Rio de Janeiro, Brazil., Iheringia Series Zoologie 95(1): 57-64

da Rocha, Rosana M.; Kremer, Laura P.; Baptista, Mariah S.; Metri, Rafael (2009) Bivalve cultures provide habitat for exotic tunicates in southern Brazil., Aquatic Invasions 4(1): 195-205

de Rivera, Catherine, and 27 authors (2005) Broad-scale non-indigenous species monitoring along the West Coast in National Marine Sanctuaries and National Estuarine Research Reserves report to National Fish and Wildlife Foundation, National Fish and Wildlife Foundation, Washington, D.C.. Pp. <missing location>

Fisheries and Oceans Canada 2018b Haplosporidium costale (SSO) of Oysters. https://www.dfo-mpo.gc.ca/science/aah-saa/diseases-maladies/hcoy-eng.html



Florida Museum of Natural History 2009-2013 Invertebrate Zoology Master Database. <missing URL>



Huang, Xuguang, Bingyu;; Guo, Donghu; Zhong;, Yanping; Li, Shunxing; Liu, Xin;; Laws, Edward A.; Huang, Bangqin (2021) Blackfordia virginica blooms shift the trophic structure to smaller size plankton in subtropical shallow waters, Marine Pollution Bulletin 182(111990): Published online

Lambert, Charles C; Lambert, Gretchen (2003) Persistence and differential distribution of nonindigenous ascidians in harbors of the Southern California Bight., Marine Ecology Progress Series 259: 145-161

Lins, Daniel M. ; Rocha, Rosana M. (2023) Marine aquaculture as a source of propagules of invasive fouling species , Polar Biology 11(e5456): Published online

Monniot, Claude; Monniot, Francoise; Griffiths, Charles; Schleyer, Michael (2001) South African Ascidians., Annals of the South African Museum 108(1): 1-141

Monniot, Francoise; Monniot, Claude (2001) Ascidians from the tropical western Pacific., Zoosystema 23(2): 201-383

Montanaro, Renee C.; O’Connor, Nancy J. (2024) Temporal and spatial refugia modify predation risk for non-native crabs in rocky intertidal habitats, PeerJ 22(e16852): Published online
DOI 10.7717/peerj.16852

New Zealand, Ministry of Primary Industries 2015 <em>Botrylloides giganteum</em> (Sea Squirt). <missing URL>



Nydam, Marie L.; Lemmon, Alan R.; Cherry, Jesse R.; Michelle L. Kortyna3, Clancy, Darragh L.; Hernandez, Cecilia;; Cohen, C. Sarah (2021) Phylogenomic and morphological relationships among the botryllid ascidians (Subphylum Tunicata, Class Ascidiacea, Family Styelidae), Scientific Reports 11(8351): Published online

Quintanilla, Elena; Thomas Wilke; Ramırez-Portilla, Catalina; Sarmiento, Adriana; Sanchez, Juan A. () , None <missing volume>: <missing location>

Quintanilla, Elena; Thomas Wilke; Ramırez-Portilla, Catalina; Sarmiento, Adriana; Sanchez, Juan A.2017 (2017) Taking a detour: invasion of an octocoral into the Tropical Eastern Pacific, Biological Invasions <missing volume>(17): 2583–2597
DOI 10.1007/s10530-017-1469-2

Riding, Tim; Morrisey, Don; Wilkens, Serena; Inglis, Graeme (2014) Marine and freshwater: Marine surveillance annual report, Surveillance 41(3): 59-62

Rodrigues, S. A.; da Rocha, R. M. (1993) Littoral compound Ascidians (Tunicata) from Sao Sebastiao, Estado de Sao Paulo, Brazil., Proceedings of the Biological Society of Washington 106: 728-739

Rodriguez, Laura F. (2006) Can invasive species facilitate native species? Evidence of how, when, and why these impacts occur., Biological Invasions 8: 927-939

Rodriguez, Laura F.; Ibarra-Obando, Silvia E. (2008) Cover and colonization of commercial oyster (Crassostrea gigas) shells by fouling organisms in San Quintin Bay, Mexico, Journal of Shellfish Research 27(2): 337-343

Ruiz, Gregory M.; Geller, Jonathan (2018) Spatial and temporal analysis of marine invasions in California, Part II: Humboldt Bay, Marina del Re, Port Hueneme, and San Francisco Bay, Smithsonian Environmental Research Center & Moss Landing Laboratories, Edgewater MD, Moss Landing CA. Pp. <missing location>

Ryland, John S. (2015) Gender of the genus Botrylloides Milne Edwards (1841) [Tunicata: Ascidiacea], Zootaxa 3973(2): 398-400

Simkanin, Christina; Fofonoff, Paul W.; Larson, Kriste; Lambert, Gretchen; Dijkstra, Jennifer A.; Ruiz, Gregory M. (2016) Spatial and temporal dynamics of ascidian invasions in the continental United States and Alaska, Marine Biology 163: Published online

U.S. National Museum of Natural History 2002-2021 Invertebrate Zoology Collections Database. http://collections.nmnh.si.edu/search/iz/



Van Name, Willard G. (1945) The North and South American ascidians, Bulletin of the American Museum of Natural History 84: 1-462