Invasion History

First Non-native North American Tidal Record: 2001
First Non-native West Coast Tidal Record: 2001
First Non-native East/Gulf Coast Tidal Record:

General Invasion History:

Watersipora n. sp. is a new, undescribed species which was identified from California harbors using molecular methods (. Its origin and worldwide range are unknown, but its spotty distribution on the California coast (Oceanside Harbor, San Diego County, to Humboldt Bay) suggestive of being introduced. Aside from the California records, it has been collected from Puget Sound and one location in South Korea. It is an encrusting calcified bryozoan known from rocks, pilings, floats and fouling plates

North American Invasion History:

Invasion History on the West Coast:

A new species of Watersipora (here called n. sp.) was identified by Mackie et al. (2006) from specimens collected in 1997-2001 in Santa Cruz Harbor, California, by molecular methods (mitochondrial COI sequences = cytochrome c oxidase subunit 1 DNA). Its origin and worldwide distribution are unknown, but its spotty distribution on the California coast is suggestive of being introduced (Geller et al. 2008). Using specimens coming primarily from the Moss Landing Marine Laboratory Surveys (2000-2001) conducted in California harbors, Watersipora n. sp. was found from Port Hueneme and Channel Island Harbors near Oxnard, north to Humboldt Bay (Geller et al. 2008; Mackie et al. 2012). The harbors and estuaries with this bryozoan included Morro Bay, Monterey Bay, Moss Landing Harbor, San Francisco Bay (Richmond Marina), Bodega Harbor and Humboldt Bay. Watersipora n. sp. was the only Watersipora identified in Morro Bay, Bodega Harbor, and Humboldt Bay, and was found at intermediate frequencies in Moss Landing and San Francisco and at low abundance in Santa Barbara and Marina Del Rey (Geller et al. 2008; Mackie et al. 2012).  It was also found in Puget Sound in 2010 (Mackie et al. 2012)

Invasion History Elsewhere in the World:

In a worldwide survey of the genus, Watersipora n. sp. was found in only one location outside California, in Namhae Sangju, on Namhaedo Island, on the south coast of South Korea (Mackie et al. 2012). It is unclear whether this species is native or introduced there.


Description

A new species of Watersipora (here called n. sp.) was identified by molecular means by Mackie et al. (2006). It is genetically distinct from four other species of Watersipora. Watersipora n. sp. has (on average) slightly longer zooid length compared to W. subtorquata and W. subovoidea, but cannot be reliably separated from W. subtorquata by morphological characters (Geller et al. 2008; Laruson, et al. 2012; Mackie et al. 2012; Gauff et al. 2023).

NOTE: A recent revision of the taxonomy of the genus Watersipora presented a drastic change in the nomenclature and worldwide biogeography of the genus. According to Vieira et al. (2015), W. subtorquata is absent from the West Coast of North America. On their map, the 3 species on the West Coast are W. subatra, W. atrofusca, and W. arcuata. Watersipora subatra occurs in the Western Pacific from Japan to New Zealand, while W. subatra was identified only from California and Pacific Mexico. Watersipora subtorquata is widely distributed in the tropical subtropical Atlantic and Mediterranean, Red Sea, and Indo-West Pacific. Another previously identified species W. subovoidea has been abolished and partially synonymized with an earlier name, until recently regarded as obsolete, W. cucullata (Vieira et al. 2015). This worldwide revision of the genus is at odds with current molecular studies (Mackie et al. 2006; Mackie et al. 2012). Vieira et al.'s (2015) map includes only a small number of West Coast samples. A larger regional sample will be required to reconcile morphological and molecular taxonomy of Watersipora on the West Coast of North America. A  map based on molecular identification found 4 species of Watersipora in southern California, including W. n. sp., W. arcuata, W. subatra, W. subtorquata, and W. atrofusca (native?) (Gauff et al. 2023).


Taxonomy

Taxonomic Tree

Kingdom:   Animalia
Phylum:   Bryozoa
Class:   Gymnolaemata
Order:   Cheilostomata
Suborder:   Ascophora
Family:   Watersiporidae
Genus:   Watersipora
Species:   n. sp.

Synonyms

Potentially Misidentified Species

Watersipora arcuata
Banta 1969 Described from San Diego, where it was a recent introduction. Possibly native to tropical-subtropical East Pacific, introduced to Hawaii, Australia, and New Zealand (Banta 1969; Mackie et al. 2006; Mackie et al. 2012).

Watersipora subovoidea
(d'Orbigny 1852), described from the Aegean Sea. Re-described and redefined by Ryland et al. (2009).

Watersipora subtorquata
(d'Orbigny 1852) Described from Brazil, Re-described and redefined morphologically by Ryland et al. (2009). It has been characterized in molecular studies by Mackie et al. (2006) and Mackie et al. (2012).

Ecology

General:

Life History- Watersipora n. sp. is an encrusting calcified bryozoan, a colony composed of many individual zooids. The zooids feed by extending the ciliated tentacles of the lophophore as a funnel, creating a current, and driving food particles into their mouths. The food is guided along the tentacles and through the pharynx by the cilia. Larger food particles can be moved or captured by flicking or contracting the tentacles (Barnes 1983). Larvae of Watersipora spp. are lecithotrophic, and have a short planktonic period (less than 1 day, Mackie et al. 2006). Larvae settle on a substrate and metamorphose into the first zooid of a colony, an ancestrula (Barnes 1983).

Ecology- Watersipora n. sp. is known from pilings, rocks, floats and fouling plates (Mackie et al. 2006; Geller et al. 2008).

Food:

Phytoplankton, detritus

Trophic Status:

Suspension Feeder

SusFed

Habitats

General HabitatCoarse Woody DebrisNone
General HabitatMarinas & DocksNone
General HabitatRockyNone
Salinity RangePolyhaline18-30 PSU
Salinity RangeEuhaline30-40 PSU
Tidal RangeSubtidalNone
Vertical HabitatEpibenthicNone

Life History


Tolerances and Life History Parameters

Broad Temperature RangeNoneCold temperate-Warm temperate
Broad Salinity RangeNonePolyhaline-Euhaline

General Impacts

Ecological Impacts

Competition - Watersipora n. sp. is a newly identified and still undescribed species, so knowledge of its ecology and impacts is limited. However, it was found to monopolize sites in Morro Bay, Bodega Bay, and Humboldt Bay, California (Geller et al. 2008; Wilson 2011).

Habitat Change- After spreading over surfaces, Watersipora n. sp. colonies in Humboldt Bay, California grew upwards and formed a three-dimensional structure which was utilized by a variety of organisms, increasing diversity on experimental plates (Wilson 2011).


Regional Impacts

NEP-VNorthern California to Mid Channel IslandsEcological ImpactCompetition
Watersipora n. sp. is a newly identified, and still undescribed species, so knowledge of its ecology and impacts is limited. However, it was found to monopolize sites in Morro and Bodega Bays (Geller et al. 2008; Mackie et al. 2012).
P070Morro BayEcological ImpactCompetition
Watersipora n. sp. is a newly identified, and still undescribed species, so knowledge of its ecology and impacts is limited. However, it was found to monopolize sites in Morro Bay (Geller et al. 2008).
P112_CDA_P112 (Bodega Bay)Ecological ImpactCompetition
Watersipora n. sp. is a newly identified, and still undescribed species, so knowledge of its ecology and impacts is limited. However, it was found to monopolize sites in Bodega Bay (Geller et al. 2008).
NEP-IVPuget Sound to Northern CaliforniaEcological ImpactCompetition
Watersipora n. sp. is a newly identified, and still undescribed species, so knowledge of its ecology and impacts is limited. However, it was found to monopolize sites in Humboldt Bay (Geller et al. 2008). Wilson (2001) found that it initially out-competed other species on fouling plates, coming to dominate the surface of the plates.
P130Humboldt BayEcological ImpactCompetition
Watersipora n. sp. is a newly identified, and still undescribed, species, so knowledge of its ecology and impacts is limited. However, it was found to monopolize sites in Humboldt Bay (Geller et al. 2008). Wilson (2001) found that it initially out-competed other species on fouling plates, coming to dominate the surface of the plates.
NEP-VNorthern California to Mid Channel IslandsEcological ImpactHabitat Change
Watersipora sp.(either subtorquata or n. sp.; Geller et al. 2008) had more than 10% cover on fouling plates. Native diversity was correlated with exotic diversity, as both groups of organisms occupied the three-dimensional structure created by colonies (Sellheim et al. 2010). 
P112_CDA_P112 (Bodega Bay)Ecological ImpactHabitat Change
Watersipora sp.(either subtorquata or n. sp.; Geller et al. 2008) had more than 10% cover on fouling plates. Native diversity was correlated with exotic diversity, as both groups of organisms occupied the three-dimensional structure created by colonies (Sellheim et al. 2010).
NEP-IVPuget Sound to Northern CaliforniaEcological ImpactHabitat Change
As Watersipora n. sp. colonies in Humboldt Bay came to dominate the two-dimensional surface of fouling plates, they grew upwards, forming a three-dimensional structure which was utilized by a variety of organisms, increasing the diversity on plates (Wilson 2011).
P130Humboldt BayEcological ImpactHabitat Change
As colonies came to dominate the two-dimensional surface of the fouling plates, they grew upwards, forming a three-dimensional structure which was utilized by a variety of organisms, increasing the diversity or species on the plates (Wilson 2011).
CACaliforniaEcological ImpactCompetition
Watersipora n. sp. is a newly identified, and still undescribed species, so knowledge of its ecology and impacts is limited. However, it was found to monopolize sites in Bodega Bay (Geller et al. 2008)., Watersipora n. sp. is a newly identified, and still undescribed, species, so knowledge of its ecology and impacts is limited. However, it was found to monopolize sites in Humboldt Bay (Geller et al. 2008). Wilson (2001) found that it initially out-competed other species on fouling plates, coming to dominate the surface of the plates., Watersipora n. sp. is a newly identified, and still undescribed species, so knowledge of its ecology and impacts is limited. However, it was found to monopolize sites in Morro Bay (Geller et al. 2008)., Watersipora n. sp. is a newly identified, and still undescribed species, so knowledge of its ecology and impacts is limited. However, it was found to monopolize sites in Morro and Bodega Bays (Geller et al. 2008; Mackie et al. 2012).
CACaliforniaEcological ImpactHabitat Change
Watersipora sp.(either subtorquata or n. sp.; Geller et al. 2008) had more than 10% cover on fouling plates. Native diversity was correlated with exotic diversity, as both groups of organisms occupied the three-dimensional structure created by colonies (Sellheim et al. 2010)., As colonies came to dominate the two-dimensional surface of the fouling plates, they grew upwards, forming a three-dimensional structure which was utilized by a variety of organisms, increasing the diversity or species on the plates (Wilson 2011)., Watersipora sp.(either subtorquata or n. sp.; Geller et al. 2008) had more than 10% cover on fouling plates. Native diversity was correlated with exotic diversity, as both groups of organisms occupied the three-dimensional structure created by colonies (Sellheim et al. 2010). 

Regional Distribution Map

Bioregion Region Name Year Invasion Status Population Status
P112 _CDA_P112 (Bodega Bay) 2007 Def Estab
P080 Monterey Bay 2006 Def Estab
P130 Humboldt Bay 2007 Def Estab
P090 San Francisco Bay 2002 Def Estab
P062 _CDA_P062 (Calleguas) 2006 Def Estab
P065 _CDA_P065 (Santa Barbara Channel) 2007 Def Estab
P070 Morro Bay 2007 Def Estab
NEP-IV Puget Sound to Northern California 2007 Def Estab
NEP-V Northern California to Mid Channel Islands 2001 Def Estab
NEP-VI Pt. Conception to Southern Baja California 2006 Def Estab
P023 _CDA_P023 (San Louis Rey-Escondido) 2007 Def Estab
P060 Santa Monica Bay 2007 Def Estab
NEP-III Alaskan panhandle to N. of Puget Sound 2010 Def Estab
NWP-3a None 0 Crypto Estab
P290 Puget Sound 2010 Def Estab

Occurrence Map

OCC_ID Author Year Date Locality Status Latitude Longitude

References

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

Boyle, Michael; Janiak, Dean; Craig, Sean (2006) Succession in a Humboldt Bay fouling community: The Role of Exotic Species, Larval Humboldt Bay Marine Fouling Settlement and Winter Storms, In: (Eds.) Peoceedings of the 2004 Humboldt Bay Symposium. , San Diego. Pp. 215-234

Duncan, Meredyth; Chow, Benson; Myron, Kevin; Stone, Jaden; Hubbell, Mark; Schriock, Elizabeth; Hunt, Carol; Khtikian, W. Kent ; Cohen, C. Sarah (2022) First report of genetic data from two invasive Watersipora (Bryozoa) species in the central California coast rocky intertidal, Aquatic Invasions 17: Published online

Gauff, Robin P. M.; Bouchoucha, Marc; Curd, Amelia; Droual, Gabin; Evrard, Justine; Gayet, Nicolas; Nunes. Flavia (2023) First joint morphological and molecular detection of Watersipora subatra in the Mediterranean Sea presented in an updated genus phylogeny to resolve taxonomic confusion, Aquatic Invasions 18(3): 295-312

Geller, Jonathan; Mackie, Joshua; Schroeder, Gregory; Gerhinger; Daphne (2008) <missing title>, Submitted to California Department of Fish and Game, Sacramento. Pp. <missing location>

Laruson, Aki J.; Craig, Sean F.; Messer, Kirk J.; Mackie, Joshua A. (2012) Rapid and reliable inference of mitochondrial phylogroups among Watersipora species, an invasive group of ship-fouling species (Bryozoa, Cheilostomata), Conservation Genetic Resources 4: 617-619

Mackie, Joshua A.; Darling, John A.; Geller, Jonathan B. (2012) Ecology of cryptic invasions: latitudinal segregation among Watersipora (Bryozoa) species, Scientific Reports 2(871): 1-10

Mackie, Joshua A.; Keough, Michael J.; Christidis, Les (2006) Invasion patterns inferred from cytochrome oxidase I sequences in three bryozoans, Bugula neritina, Watersipora subtorquata; and Watersipora arcuata., Marine Biology 149: 285-295

Mackie, Joshua A.; Wostenberg, Darren; Doan, Michael; Craig, Sean F. ; Darling, John A. (2014) High-throughput Illumina sequencing and microsatellite design in Watersipora (Bryozoa), a complex of invasive species, Conservation Genetic Resources 6: 1053-1055

Sellheim, Kirsten; Stachowicz, John J.; Coates, R. Cameron (2010) Effects of a nonnative habitat-forming species on mobile and sessile epifaunal communities, Marine Ecology Progress Series 398: 69-80

Wilson, Emily Erin (2011) <missing title>, Humboldt State University, Eureka CA. Pp. <missing location>