Invasion History

First Non-native North American Tidal Record: 1982
First Non-native West Coast Tidal Record: 1993
First Non-native East/Gulf Coast Tidal Record: 1982

General Invasion History:

Since 1990, scientists in several parts of the world have observed the growth and spread of an unidentified species of Didemnum in the temperate marine waters of New Zealand, North America, and Europe. While there have been differing opinions on the identity of these different populations (Kott 2002; Kott 2004), some have suspected that it is a single species (Bullard et al. 2007). Recently, genetic and morphological studies have apparently resolved the great Didemnum species debate. The first description of this tunicate was by Kott (2002). Specimens from New Zealand were intensely reviewed and the study concluded that the correct name is D. vexillum (Lambert 2009; Stefaniak et al. 2009). Didemnum vexillum probably originated from the northwest Pacific, possibly Japan (Lambert 2009). Genetic analysis supports the native status of populations in eastern Japan. Further sampling in the northwest Pacific is needed to determine the full extent of the native range (Stefaniak et al. 2012). It has invaded the West and East Coasts of North America including Mexico, California, Alaska and New York, Massachusetts and Maine.

North American Invasion History:

Invasion History on the West Coast:

Didemnum vexillum was first reported from San Francisco Bay in 1993 and it seemed to be limited to the saltier (>26 ppt) parts of the bay (Cohen 2005; Cohen et al. 2005; Bullard et al. 2007; USGS Woods Hole Science Center 2008; Ruiz et al., unpublished data). North of San Francisco Bay, D. vexillum was found in Tomales Bay (CA) and Humboldt Bay (CA) in 2001, Bodega Harbor (CA) in 2003, Puget Sound (WA) in 2004, Okeover Inlet (British Columbia) in 2003 (Bullard et al. 2007) and Jervis Inlet (British Columbia; USGS Woods Hole Science Center 2008). In 2010, it was found in Sitka (AK), its northernmost site on the West Coast (Cohen et al. 2011). South of San Francisco Bay, D. vexillum was found in Half Moon Bay (CA) in 1997, Monterey Bay (CA) and Elkhorn Slough (CA) in 1998, Morro Bay (CA) in 2000, and Port San Luis (CA) in 2002 (Bullard et al. 2007). In 2007, it was found in Mission Bay (CA) (USGS Woods Hole Science Center 2008). In 2005, it was found fouling oysters (Crassostrea gigas) in Bahia San Quintin, Mexico (Rodriguez and Ibarra-Obando 2008).

On the West Coast, the sequence of occurrences suggests an introduction to San Francisco Bay, followed by dispersal from shipping and aquaculture to the north and south. However, fishermen in British Columbia claim that D. vexillum may have been present for more than a decade before its official discovery (USGS Woods Hole Science Center 2011).

Invasion History on the East Coast:

Didemnum vexillum was first reported in 1982 from the Damariscotta River estuary, Maine (Dijkstra and Nolan 2011). This occurrence has sometimes been attributed to experimental culture of Pacific Oysters (Crassostrea gigas) in the 1970s (Shatkin et al. 1997), but these oysters were hatchery-reared seed, and would not have be fouled with tunicates. Ship fouling from Europe, where fouled Pacific Oysters were planted and reared, is the most probable vector (James T. Carlton, personal communication). In 1996, D. vexillum was collected on Tillies Bank, MA. A few years later in 1998, it was collected on Stellwagen Bank and Georges Bank, MA where it has continued to spread in offshore waters (Bullard et al. 2007). By 1998, D. vexillum was present in the Cape Cod Canal (Sandwich, MA) and had been tentatively identified in photographs taken of floating docks from Woods Hole in 1998 (Bullard et al. 2007; USGS Woods Hole Science Center 2008). In 2000, it was collected in Eel Pond at Woods Hole, MA and was found along the southern side of the Cape and east to Orleans, MA (USGS Woods Hole Science Center 2008). Again in 2000, it was collected in Buzzards Bay, MA and Narragansett Bay, RI (MIT Sea Grant 2008; Osman and Whitlatch 2007, Bullard et al. 2007), as well as in eastern Long Island Sound, NY (Osman and Whitlatch 2007). In 2004, D. vexillum reached its current southern limit of Shinnecock Bay, NY (Bullard et al. 2007; USGS Woods Hole Science Center 2008). There may be a temperature and/or salinity threshold that complicates its spread to warmer (e.g. southern) and low salinity waters, given that its presence seems to be limited to the mouth of estuaries (e.g. Long Island Sound, NY and Narragansett Bay, RI). Currently, D. vexillum ranges from Parrsboro, Nova Scotia to Shinnecock Inlet, NY (Bullard et al. 2007; USGS Woods Hole Science Center 2008; Moore et al. 2014). In recent surveys (2006-2009), it was not found in New Brunswick waters, although it was found in Eastport, Maine, only 2 km from the border (Martin et al. 2011). However, in 2013 it was found on the Bay of Fundy, Nova Scotia (Moore et al. 2014). 

Invasion History Elsewhere in the World:

Northeast Atlantic: The earliest report of Didemnum vexillum from Europe was along the Dutch coastline in 1991. It remained relatively rare until 1996 when the population rapidly expanded, especially in the province of Zeeland, Netherlands (Gittenberger 2007). Subsequently, in 2001, D. vexillum was found growing on the face of a brick quay (wharf or reinforced bank) and overgrowing other invertebrates (barnacles, mussels, tunicates, etc.) in the Port of Le Havre, France. In 2002 it was found growing on ropes and overgrowing other invertebrates in Perros-Guirec, Brittany (USGS Woods Hole Science Center 2011). In 2005, it was found in Ireland’s Malahide Estuary attached to boats, pontoons, ropes, buoys, seaweed and mussels (Minchin and Sides 2006; USGS Woods Hole Science Center 2011). In 2008-2009, D. vexillum was found on the coast of Spain, in the towns of Santander, Baiona, Moana, Corme-Porto, and Gijon (El Nagar et al. 2010).

In 2010, D. vexillum was discovered growing in the Lagoon of Venice, at the head of the Adriatic Sea, the first record from the Mediterranean Sea (Tagliopietra et al. 2012). In 2012, it was found growing on oysters in Fangar Bay, in the Ebro Delta, on the Spanish Mediterranean coast. Genetic analysis suggested the likely source was oyster cultures on the French Atlantic Coast. This invasion suggests that D. vexillum has greater capacity, than previously thought, to invade warm waters (Ordonez et al. 2015).

Southwest Pacific: In October 2001, An unidentified species of Didemnum was discovered fouling mooring posts and boats in Whangamata Harbour, New Zealand. Patricia Kott described it as D. vexillum, and considered it a native species, previously unnoticed in New Zealand (Kott 2002). In December 2001, this organism was found overgrowing a barge in Shakespeare Harbour near Picton, New Zealand. In 2003, eradication of the fouling on the barges, recreational vessels, moorings, salmon cages and wharf pilings was attempted, using a variety of methods (Coutts and Forrest 2007). Fouled areas were wrapped in plastic and treated with chlorine, moorings were water-blasted, boats were cleaned and repainted with antifouling paints, the seabed was covered with fresh dredge spoil, and riprap was covered with Geotextile fabric and treated. However, some tunicates survived in joints in the riprap and eventually repopulated the area (Coutts and Forrest 2007).


Description

Didemnum vexillum is an aggressive and rapidly spreading colonial tunicate species forming extensive thin sheets which often overgrow rocks, shells, other sessile organisms (e.g. sponges, hydroids, oysters), and even itself ultimately forming large sponge-like masses. These masses often have long, flexible leaf or flag like projections that are cylindrical and branched. Large D. vexillum colonies may appear to be folding in on themselves and neighboring surfaces. Colonies are yellowish-cream in color with the yellow pigment observed in the gut, eggs, and embryos. The thorax of its zooids are white in color. Star shaped calcareous spicules are patchily distributed in the surface layer and in the cloacal cavity; patchiness increases closer to the tunic surface. Spicules are approximately 58 µm in diameter with 9-11 conical rays. The oral siphon is short with only six lobes. The atrial siphon is surrounded by large clumps of spicules around the opening. There are 8-9 stigmata in an anterior row of the oral cavity. The post-stomach gut forms a double loop in the abdomen. Zooids are about 1 mm long and are arranged along the common cloacal canals that extend through the colony. Didemnum vexillum has nine coils of vas deferens around the testis. Embryos are approximately 600 µm (with tail wrapped around body) and are incubated in the core of the tunic, and not within each zooid (Kott 2002, as D. vexillum, New Zealand).

Morphological identification criteria for Didemnum species, particularly in the USA, have not been re-evaluated since Van Name published his monograph in 1945. Since that time, there has been a turbulent taxonomic evolution in the identification of Didemnum species. The near simultaneous discovery of outbreaks of similar didemnids in New Zealand, the East and West Coast (North America), and Europe raised questions of whether a single or multiple species existed, and whether the outbreaks were true invasions or simply population booms of native species (Bullard et al. 2007). Kott (2002) named the New Zealand form D. vexillum, but found morphological differences in specimens from the northwest Atlantic (New Hampshire) and therefore named these as a separate species, D. vestum. Gretchen Lambert investigated the possibility that this species was conspecific with D. lahillei, described from Brittany in 1909. However, she found that the type material (physical representative specimen) was a mixture of several species (Lambert 2009). In 2005, others began a molecular (18S rDNA) study using the samples from New Hampshire, New Zealand and Japan, and found that all of the samples were the same species, for which D. vexillum was the valid name (Lambert 2009; Stefaniak et al. 2009). Genomic sampling of populations worldwide indicates high genetic diversity, but also genetic differentiation among populations. Of two major groups with different COI (Cytochrome oxidase I) groups, only one was widley introduced, with three major colonization events (Casso et al. 2018).


Taxonomy

Taxonomic Tree

Kingdom:   Animalia
Phylum:   Chordata
Subphylum:   Tunicata
Class:   Ascidiacea
Order:   Aplousobranchia
Family:   Didemnidae
Genus:   Didemnum
Species:   vexillum

Synonyms

Didemnum sp. A (Bullard et al., 2009)
Didemnum vestum (Kott, 2004)

Potentially Misidentified Species

Didemnum albidum
NW Atlantic native

Didemnum areolatum
NW Pacific native

Didemnum carnulentum
NE Pacific native

Didemnum maculosum
NE Atlantic native

Didemnum misakiense
NW Pacific native

Didemnum pacificum
NW Pacific native

Didemnum pardum
NW Pacific native

Ecology

General:

Life History- A colonial 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 family Didemnidae have small zooids, completely embedded in an encrusting and thin tunic. Each zooid has an oral siphon and an atrial aperture which opens 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 that develop into larvae. Buds can form from the body wall of the zooids. Colonies vary in size ranging from small clusters of zooids to huge spreading masses. The zooids are hermaphroditic, which means both eggs and sperm are released into the atrial chamber. Eggs may be self-fertilized or fertilized by sperm from nearby animals, but some species have a partial block to self-fertilization. Fertilized eggs are brooded within the tunic until they hatch into lecithotrophic (non-feeding, yolk-dependent) tadpole larvae. The larva has a muscular tail and a notochord, eyespots, and a set of adhesive papillae. The larvae are expelled upon hatching and swim briefly before settlement. Swimming periods are usually less than a day, but some larvae settle immediately after release or swim for longer periods if the water temperature is low. In experiments, 10% of larvae remained viable after a delay of 36 h. In field experiments, most settlement occured within 250 m of the parent population, but some settlement is possible at distances of 1 km or more (Fletcher et al. 2012). On settlement the tail is absorbed, the gill basket expands, and the tunicate begins to feed by filtering (Van Name 1945; Barnes 1983).

Colonies of D. vexillum can also disperse by fragmentation and zooids are capable of reproduction while suspended in the water column. Fragments of colonies can remain suspended for up to three weeks, and can reattach to surfaces and grow. However, the apparent health of the colony declines, the longer it is suspended in the water column. The viability of fragments is a concern for attempts to control or eradicate this species (Morris and Carman 2012). Fragments will reattach on eelgrass and artificial surfaces at water temperatures of 6-10 °C, but at a lower rate than at summer temperatures (16-22 °C) (Carman et al. 2014). Exposure to high temperatures results in increased DNA methlylation, and decreased growth rates, which may 'buy survival time' as a stress resonse (Hawes et al. 2018). The rapid spread of D. vexillum may be due to the ability of genetically different colonies to fuse, forming rapidly growing ramets, forming transient chimeras, stretching and dispersing across a substrate, and later resegregating (Fidler et al. 2018).

In all part of its native and introduced range, D. vexillum is more frequently reported from anthropogenic stuctures than from natural surfaces, (Simkanin et al. 2012). Dock floats are especially favored habitats, probably because their motion provides rapid water exchange, and a fresh supply of food-laden water (Glasby 2001). Other colonized man-made structures include pilings, piers, aquaculture structures, and boat hulls (Carman et al. 2010; Davidson et al. 2010; Simkanin et al. 2012). Natural habitats include rocky reefs, gravel bottoms, bivalve colonies, seaweeds, and eelgrass (Valentine et al. 2007; Carman and Grunden 2010 Simkanin et al. 2012; Carman et al. 2016).

Food:

Phytoplankton, bacteria, detritus

Consumers:

Starfish, urchins

Trophic Status:

Suspension Feeder

SusFed

Habitats

General HabitatCoarse Woody DebrisNone
General HabitatUnstructured BottomNone
General HabitatOyster ReefNone
General HabitatMarinas & DocksNone
General HabitatRockyNone
General HabitatBedrockNone
General HabitatVessel HullNone
General HabitatGrass BedNone
Salinity RangePolyhaline18-30 PSU
Salinity RangeEuhaline30-40 PSU
Tidal RangeSubtidalNone
Tidal RangeLow IntertidalNone
Vertical HabitatEpibenthicNone


Tolerances and Life History Parameters

Minimum Temperature (ºC)-2Field data, Bullard et al. 2007
Maximum Temperature (ºC)24Field data, Bullard et al. 2007, reduced growth at 23 C, experimental data, McCarthy et al. 2007
Minimum Salinity (‰)19Field and laboratory data (Bullard et al. 2007; Gröner et al. 2011; Hawes et al. 2018). Growth and survival at medium (15-28 PSU) and low (10-26 PSU) sites was greatly reduced compared to a high-salinity site (26-30 PSU) in the Thames estuary, Connecticut (Bullard and Whitlach 2009; Auker 2019).
Maximum Salinity (‰)35Highest observed?
Minimum Reproductive Temperature14Onset of spring recruitment, but fall reproduction ceases at 9-11 C (Valentine et al. 2009). In New Zealand, recruitment was not detected when temperatures dropped below 12 C, but some larvae were present in the the tissues of colonies (Fletcher et al. 2013).
Maximum Reproductive Temperature20end of spring recruitment (Valentine et al. 2009)
Minimum Duration0Larvae can settle immediately on release (Fletcher et al. 2012)
Maximum Duration1.5 In experiments, 10% of larvae remained viable after a delay of 36 h (Fletcher et al. 2012)
Broad Temperature RangeNoneCold temperate
Broad Salinity RangeNonePolyhaline-Euhaline

General Impacts

Didemnum vexillum is widely considered to be an invasive species with potentially important economic and ecological impacts. As a recent invader in many parts of the world, the extent of its impacts have only just begun to be studied. Didemnum vexillum is unique in that, unlike many marine invasive organisms, it is not only common in confined, disturbed, and polluted harbors and estuaries, but is also common in the more ‘pristine’ waters of Georges Bank (MA), British Columbia and New Zealand. Consequently, its invasions potentially have major implications on industries that take place in 'cleaner' waters, such as fisheries and aquaculture (Bullard et al. 2007; Valentine et al. 2007), and may impact natural ecosystems by significantly altering the local habitat (Bullard et al. 2007; Valentine et al. 2007).  

Economic Impacts

Fisheries: Economic impacts on 'wild' fisheries (e.g. bottom fishes, scallops, lobsters, mussels, etc.) are expected due to D. vexillum altering habitat and food resources on Georges Bank and elsewhere in the world (Bullard et al. 2007; Valentine et al. 2007). Didemnum vexillum is considered a major threat to New Zealand's mussel industry because of its demonstrated invasiveness on artificial structures, and its ability to over-grow and smother mussels (Coutts and Forrest 2007). To help save the shellfish industry in New Zealand, $650,000 NZ dollars were spent on eradication of D. vexillum (Coutts and Forrest 2007). However, the attempts to eradicate D. vexillum were unsuccessful and it was soon seen spreading to mussel farms in the region, resulting in significant crop losses (Coutts and Forrest 2007).

Shipping and Industry: Since New Zealand relies on sea-borne shipping for over 90% (by volume) of its international commerce (Hewitt et al., 2004), D. vexillum is considered a serious and persistent fouling pest to their commercial shipping industry and ports (Coutts and Forrest 2007).


Ecological Impacts

Competition: Rapid population explosions are known to reduce the abundance of previously established benthic species and cause significant changes in benthic community structure (Whitlatch et al. 1995; Bak et al. 1996; Lambert 2001; Castilla et al. 2004). Since D. vexillum can attach and encrust nearly every substrate it encounters, competition for resources (e.g. suitable attachment substrates, food, etc.) becomes a problem. In many locations, D. vexillum overgrows benthic biota, such as seaweeds, scallops, mussels, and other invertebrates (Bullard et al. 2007; Auker and Oviatt 2008; Gittenberger 2007; Valentine et al. 2007; Dijkstra and Harris 2009) which further exacerbates competition pressures. However, its competitiveness is partly related to environmental conditions. In laboratory and field conditions, D. vexillum was most competitive at sites with cooler temperatures (approx. 15-21°C), where it outgrew other tunicates, such as Botrylloides violaceus, Botryllus schlosseri, and Ascidiella aspersa (McCarthy et al. 2007). However, D. vexillum was less dominant on plates where other colonies of species had been established (Osman and Whitlatch 2007). In experiments at Eel Pond (Woods Hole), D. vexillum began to recruit later (October) than other species, however, it rapidly expanded its coverage on plates from October-December (Agius 2007). In Narragansett Bay (MA), D. vexillum dominated plates in the fall, and overgrew Blue Mussel (Mytilus edulis) recruits (Auker and Oviatt 2008). Didemnum vexillum was one of several invasive fouling species which showed increased growth (% coverage) at temperatures 3.5 and 4.5°C above the ambient temperature in Bodega Harbor (13.5°C), while the native Distaplia occidentalis showed reduced survival (Sorte et al. 2010).

In field experiments with a diversity of competitors and predators, D. vexillum was less successful in the presence of other species, suggesting that it is not a stronger competitor compared to other non-native colonial ascidians (e.g. Botrylloides violaceus, Botryllus schlosseri) (Stefaniak 2007). However, the ability of colonies to form tendrils for dispersal, to fuse, to form extensive colonies on pebble and cobble surfaces, and to resist grazing, due to calcareous spicules in the tunic, enable D. vexillum to form extensive colonies (Stefaniak 2017).

Habitat Change: Didemnum vexillum overgrows gravel, seaweeds, scallops, mussels, and other invertebrates thereby greatly altering the structure of the pre-existing habitat (Bullard et al. 2007; Auker and Oviatt 2008; Gittenberger 2007; Valentine et al. 2007). These D. vexillum mats are thought to reduce the amount of seabed surface suitable for larval settlement of other benthic species, such as sea scallops, on Georges Bank, MA. Additionally, these mats likely reduce the amount of suitable shelter available for juvenile fish and other prey organisms (Valentine et al. 2007). Sea Scallops overgrown by D. vexillum have reduced swimming speeds, and may be less able to escape predators (Dijkstra and Nolan 2011). By 2003-2006, colonial tunicates, including D. vexillum, replaced mussels (M. edulis) as the dominant species in fouling communities in Portsmouth Harbor, NH. (Dijkstra and Harris 2009). This is a major functional habitat change because while mussels provided a year-round substrate available to other organisms for settlement, tunicates, such as D. vexillum, are more resistant to secondary settlement by these other organisms. However, D. vexillum dies off seasonally and creates large areas of bare substrate available for colonization by other organisms (Dijkstra and Harris 2009). Of course this bare substrate is only available to those organisms with settlement periods that overlap with D. vexillum seasonal die offs, thereby excluding some benthic species from settlement opportunities.

Herbivory: Experiments by Byrne and  Stachowicz (2009) in Bodega Harbor (CA) indicate that D. vexillum has a lower filtration rate than the native Distaplia occidentalis. Similar results were obtained for other exotic/native pairs. It has been suggested that the cumulative effect of increased invasions in filter feeding fouling communities may increase seasonal consistency of filtration. This is probably due to spreading out of recruitment times of filter feeding organisms rather than increases in filtration rates.

Food/Prey: On Georges Bank (MA), Valentine et al. (2007) suggest that dense mats of D. vexillum colonies possibly form a physical barrier between fish and benthic prey resources, such as worms and bivalves. In Long Island Sound (NY),  predation studies by Osman and Whitlatch (2007) found that some predation did occur on D. vexillum recruits by the gastropod Mitrella lunata. Additionally, their study suggests that there was possibly a fish predator that preyed on their suspended uncaged D. vexillum treatments. However, Osman and Whitlatch (2007) state that the growth and dominance of juvenile and adult colonies of D. vexillum at Pine Island suggests that their abundance is not significantly reduced by predation.

Toxicity: Many species of Didemnum are chemically defended by a variety of compounds and for most species, including D. vexillum, this results in a lower surface pH (2-3) (Bullard et al. 2007).

Regional Impacts

NEP-VNorthern California to Mid Channel IslandsEcological ImpactCompetition
Didemnum vexillum was one of several invasive fouling species which showed increased growth (% coverage) at temperatures 3.5 and 4.5⁰C above the ambient temperature in Bodega Harbor (13.5⁰C), while the native Distaplia occidentalis showed reduced survival (Sorte et al. 2010). Didemnum vexillum was one of a group of seven non-native species, most of which were rare or absent in 1970-1971, but were among the eight most abundant species in 2005-2009. Spawning periods and abundance of species in this group appeared to be favored by a 1⁰C increase in average temperatures at this site over a 30-year period (Sorte and Stachowicz 2011). Didemnum vexillum overgrowth had a modest effect on the growth of eelgrass (Zostera marina) blades in mesocosms filled with water from Tomales Bay (Long and Grosholz 2015).
P112_CDA_P112 (Bodega Bay)Ecological ImpactCompetition
Didemnum vexillum was one of several invasive fouling species which showed increased growth (% coverage) at temperatures 3.5 and 4.5⁰C above the ambient temperature in Bodega Harbor (13.5⁰C), while the native Distaplia occidentalis showed reduced survival (Sorte et al. 2010). Didemnum vexillum was one of a group of seven non-native species, most of which were rare or absent in 1970-1971, but were among the eight most abundant species in 2005-2009. Spawning periods and abundance of species in this group appeared to be favored by a 1⁰C increase in average temperatures at this site over a 30-year period (Sorte and Stachowicz 2011).
P110Tomales BayEcological ImpactCompetition
Didemnum vexillum overgrowth had a modest effect on the growth of eelgrass (Zostera marina blades in mesocosms filled with water from Tomales Bay (Long and Grosholz 2015).
P110Tomales BayEcological ImpactHabitat Change
Didemnum vexillum faciltated growth of invertebrates (polychaetes and tanaids) on eelgrass blades (Long and Grosholz 2015).
NEP-VNorthern California to Mid Channel IslandsEcological ImpactHabitat Change
Didemnum vexillum faciltated growth of invertebrates (polychaetes and tanaids) on eelgrass blades (Long and Grosholz 2015)
CACaliforniaEcological ImpactCompetition
Didemnum vexillum was one of several invasive fouling species which showed increased growth (% coverage) at temperatures 3.5 and 4.5⁰C above the ambient temperature in Bodega Harbor (13.5⁰C), while the native Distaplia occidentalis showed reduced survival (Sorte et al. 2010). Didemnum vexillum was one of a group of seven non-native species, most of which were rare or absent in 1970-1971, but were among the eight most abundant species in 2005-2009. Spawning periods and abundance of species in this group appeared to be favored by a 1⁰C increase in average temperatures at this site over a 30-year period (Sorte and Stachowicz 2011). Didemnum vexillum overgrowth had a modest effect on the growth of eelgrass (Zostera marina) blades in mesocosms filled with water from Tomales Bay (Long and Grosholz 2015)., Didemnum vexillum overgrowth had a modest effect on the growth of eelgrass (Zostera marina blades in mesocosms filled with water from Tomales Bay (Long and Grosholz 2015)., Didemnum vexillum was one of several invasive fouling species which showed increased growth (% coverage) at temperatures 3.5 and 4.5⁰C above the ambient temperature in Bodega Harbor (13.5⁰C), while the native Distaplia occidentalis showed reduced survival (Sorte et al. 2010). Didemnum vexillum was one of a group of seven non-native species, most of which were rare or absent in 1970-1971, but were among the eight most abundant species in 2005-2009. Spawning periods and abundance of species in this group appeared to be favored by a 1⁰C increase in average temperatures at this site over a 30-year period (Sorte and Stachowicz 2011).
CACaliforniaEcological ImpactHabitat Change
Didemnum vexillum faciltated growth of invertebrates (polychaetes and tanaids) on eelgrass blades (Long and Grosholz 2015), Didemnum vexillum faciltated growth of invertebrates (polychaetes and tanaids) on eelgrass blades (Long and Grosholz 2015).

Regional Distribution Map

Bioregion Region Name Year Invasion Status Population Status
P020 San Diego Bay 2020 Prb Estab
P050 San Pedro Bay 2018 Def Estab
P062 _CDA_P062 (Calleguas) 2011 Def Estab
P100 Drakes Estero 2010 Def Estab
NEP-VI Pt. Conception to Southern Baja California 2007 Def Estab
P030 Mission Bay 2007 Def Estab
P112 _CDA_P112 (Bodega Bay) 2003 Def Estab
P069 _CDA_P069 (Central Coastal) 2002 Def Estab
NEP-IV Puget Sound to Northern California 2001 Def Estab
P130 Humboldt Bay 2001 Def Estab
P110 Tomales Bay 2001 Def Estab
P070 Morro Bay 2000 Def Estab
P080 Monterey Bay 1998 Def Estab
P086 _CDA_P086 (San Francisco Coastal South) 1997 Def Estab
NEP-V Northern California to Mid Channel Islands 1993 Def Estab
P090 San Francisco Bay 1993 Def Estab

Occurrence Map

OCC_ID Author Year Date Locality Status Latitude Longitude
697107 Introduced Species Study 2005 2005-08-25 Ferry Terminal Pier Def 37.7945 -122.3917
697108 Introduced Species Study 2010 2010-07-12 Ferry Terminal Pier Def 37.7945 -122.3917
697146 Introduced Species Study 2006 2006-07-26 Commercial Wharf Def 34.1478 -119.2077
697265 Introduced Species Study 2006 2006-08-09 Wood-loading/Barge Dock Def 40.7327 -124.2192
697336 Introduced Species Study 2011 2011-06-06 Tomales Bay Boat Launch Def 38.1991 -122.9220
697833 Introduced Species Study 2005 2005-10-04 Berkeley Marina Def 37.8676 -122.3172
697936 Introduced Species Study 2010 2010-06-02 Port of Oakland Office Def 37.7954 -122.2804
698057 Introduced Species Study 2005 2005-10-06 Point Richmond Piers Def 37.9085 -122.3913
698096 Introduced Species Study 2010 2010-07-29 San Mateo Bridge Def 37.5806 -122.2543
698276 Introduced Species Study 2005 2005-09-08 Pier 39 Def 37.8108 -122.4086
698390 Introduced Species Study 2010 2010-07-01 Richardson Bay Def 37.8588 -122.4798
698397 Introduced Species Study 2005 2005-10-21 Richardson Bay Def 37.8588 -122.4798
698446 Introduced Species Study 2006 2006-11-01 B-Dock Def 36.8027 -121.7851
698447 Introduced Species Study 2011 2011-06-21 B-Dock Def 36.8027 -121.7851
698481 Introduced Species Study 2005 2005-10-06 Santa Fe Channel - Front Def 37.9101 -122.3644
698559 Introduced Species Study 2006 2006-08-11 Slip In A Harbor Def 38.3295 -123.0565
698580 Introduced Species Study 2006 2006-07-28 Morro Bay Commercial Fishing Dock Def 35.3691 -120.8552
698650 Introduced Species Study 2006 2006-08-08 Humboldt Chevron Pier Def 40.7781 -124.1962
698821 Introduced Species Study 2011 2011-04-05 Morro Bay Boat Yard Def 35.3570 -120.8492
698824 Introduced Species Study 2006 2006-07-28 Morro Bay Boat Yard Def 35.3570 -120.8492
699138 Introduced Species Study 2010 2010-07-14 Paradise Cay Def 37.9146 -122.4776
699139 Introduced Species Study 2005 2005-10-21 Paradise Cay Def 37.9146 -122.4776
699235 Introduced Species Study 2010 2010-06-03 Treasure Island Def 37.8149 -122.3702
699238 Introduced Species Study 2005 2005-09-08 Treasure Island Def 37.8149 -122.3702
699361 Introduced Species Study 2010 2010-07-12 Saint Francis Yacht Harbor Def 37.8066 -122.4463
699370 Introduced Species Study 2005 2005-09-08 Saint Francis Yacht Harbor Def 37.8066 -122.4463
699426 Introduced Species Study 2006 2006-08-11 NE Corner of Bay Def 38.3340 -123.0511
699427 Introduced Species Study 2011 2011-06-03 NE Corner of Bay Def 38.3340 -123.0511
699579 Introduced Species Study 2010 2010-05-31 Redwood Creek - Shipping Def 37.5120 -122.2109
699580 Introduced Species Study 2005 2005-09-07 Redwood Creek - Shipping Def 37.5120 -122.2109
699661 Introduced Species Study 2005 2005-09-08 Pier 45 Def 37.8111 -122.4196
699662 Introduced Species Study 2010 2010-07-12 Pier 45 Def 37.8111 -122.4196
699901 Introduced Species Study 2010 2010-05-31 Redwood Creek - Marina Def 37.5021 -122.2130
699902 Introduced Species Study 2005 2005-09-07 Redwood Creek - Marina Def 37.5021 -122.2130
699954 Introduced Species Study 2010 2010-05-31 Dumbarton Bridge Def 37.5070 -122.1168
700047 Introduced Species Study 2010 2010-07-12 Cruise Ship Pier Def 37.8085 -122.4060
700048 Introduced Species Study 2005 2005-09-08 Cruise Ship Pier Def 37.8085 -122.4060
700080 Introduced Species Study 2006 2006-07-26 Wharf 4 Def 34.1500 -119.2100
700081 Introduced Species Study 2011 2011-04-08 Wharf 4 Def 34.1500 -119.2100
700093 Introduced Species Study 2006 2006-08-09 Wooden Structure Debris Def 40.7233 -124.2232
700191 Introduced Species Study 2006 2006-11-01 MLML Small Boats Def 36.8041 -121.7860
700496 Introduced Species Study 2005 2005-09-09 Coyote Point Marina Def 37.5905 -122.3177
700498 Introduced Species Study 2010 2010-06-01 Coyote Point Marina Def 37.5905 -122.3177
701066 Introduced Species Study 2011 2011-06-21 Middle of the Slough Def 36.8112 -121.7793
701070 Introduced Species Study 2006 2006-11-01 Middle of the Slough Def 36.8112 -121.7793
701328 Introduced Species Study 2006 2006-08-09 Dilapidated Dock Area Def 40.7291 -124.2198
701825 Introduced Species Study 2010 2010-06-02 Ballena Bay Def 37.7661 -122.2834
701831 Introduced Species Study 2005 2005-10-05 Ballena Bay Def 37.7661 -122.2834
702093 Introduced Species Study 2010 2010-07-01 Corinthian Marina Def 37.8726 -122.4563
702097 Introduced Species Study 2005 2005-10-21 Corinthian Marina Def 37.8726 -122.4563
702232 Introduced Species Study 2005 2005-08-25 Central Basin Def 37.7643 -122.3863
702333 Introduced Species Study 2010 2010-07-01 Ayala Cove Def 37.8680 -122.4350
702459 Introduced Species Study 2006 2006-08-10 Tony's Place Def 38.1466 -122.8832
702554 Introduced Species Study 2011 2011-06-29 Eureka Boat Launch Def 40.8040 -124.1766
702555 Introduced Species Study 2006 2006-08-09 Eureka Boat Launch Def 40.8040 -124.1766
702584 Introduced Species Study 2005 2005-10-06 Richmond Marina Def 37.9137 -122.3504
702708 Introduced Species Study 2005 2005-08-25 Potrero Point Def 37.7521 -122.3790
702712 Introduced Species Study 2010 2010-07-12 Potrero Point Def 37.7521 -122.3790
702993 Introduced Species Study 2005 2005-08-25 China Basin Def 37.7780 -122.3881
703090 Introduced Species Study 2011 2011-05-03 San Diego Bay Cruise Ship Terminal Def 32.7168 -117.1759
703158 Introduced Species Study 2006 2006-08-08 The Log Ride Def 40.7991 -124.1903
703565 Introduced Species Study 2006 2006-07-26 Wharf 5 Def 34.1516 -119.2072
703654 Introduced Species Study 2006 2006-07-28 Morro Bay Boat Launch Ramp Def 35.3577 -120.8510
703659 Introduced Species Study 2011 2011-04-05 Morro Bay Boat Launch Ramp Def 35.3577 -120.8510
703679 Introduced Species Study 2006 2006-08-11 SE Side of Bay Def 38.3258 -123.0410
703719 Introduced Species Study 2011 2011-06-21 North Harbor/Boat Launch Def 36.8128 -121.7880
703728 Introduced Species Study 2006 2006-11-01 North Harbor/Boat Launch Def 36.8128 -121.7880
704195 Introduced Species Study 2010 2010-06-28 Chevron Pier Def 37.9228 -122.4105
704315 Introduced Species Study 2006 2006-08-08 Parking Lot With Pallets Stacked Def 40.7977 -124.1860
704622 Introduced Species Study 2005 2005-09-09 Sierra Point Marina Def 37.6740 -122.3792
704672 Introduced Species Study 2011 2011-06-29 Aquaculture Floats Def 40.8285 -124.1648
704675 Introduced Species Study 2006 2006-08-08 Aquaculture Floats Def 40.8285 -124.1648
704700 Introduced Species Study 2011 2011-04-05 Coast Guard Pier Def 35.3707 -120.8585
715900 Ruiz et al., unpublished data 2003 Eureka Public Marina Def 40.7821 -124.1790
715901 USGS Woods Hole Science Center 2007 2003 Woodley Island Marina Def 40.8078 -124.1612
715902 Bullard et al. 2007; Stefaniak et al. 2009; USGS Woods Hole Science Center 2012 2003 2003-05-29 Spud Point Marina, Bodega Bay Def 38.3300 -123.0583
715903 de Rivera et al. 2005a 2004 Porto Bodega Marina Def 38.3338 -123.0511
715904 Bullard et al. 2007 2001 Tomales Bay Def 38.1696 -122.9100
715905 de Rivera et al. 2005a 2004 Marshall Def 38.1605 -122.8942
715906 de Rivera et al. 2005a 2004 Sacramento Landing Def 38.1496 -122.9064
715907 Ruiz et al., unpublished data; 2000 Sausalito Def 37.8591 -122.4803
715908 Ruiz et al., unpublished data 2000 Hunters Point Def 37.7244 -122.3694
715909 Ruiz et al., unpublished data 2000 Port of San Francisco Def 37.8083 -122.4311
715910 Ruiz et al., unpublished data 2000 Richmond Marina Def 37.9110 -122.3511
715911 Ruiz et al., unpublished data 2000 Treasure Island Def 37.8269 -122.3780
715913 Cohen et al. 2005 2004 2004-05-23 Pier 39, San Francisco Def 37.8269 -122.4098
715914 Cohen et al. 2005 2004 2004-05-25 Presidio Yacht Club, San Francisco Def 37.8326 -122.4741
715915 Cohen and Chapman 2005 2005 2005-11-27 San Mateo Bridge Pylon Def 37.5833 -122.2514
715917 Bullard et al. 2007 2000 Morro Bay Def 35.3378 -120.8513
715918 Bullard et al. 2007 2002 Port San Luis Def 35.1716 -120.7553
715919 USGS Woods Hole Science Center 2007 2007 2007-01-27 Catamaran Resort Hotel Dock, Mission Bay Def 32.7888 -117.2512
716870 Kovner 2012 2010 Drake's Bay Oyster Farm Def 38.0474 -122.9422
757021 G. Lambert and C. Lambert, unpublished data, in Lambert 2009 1996 Bahia Point, Mission Bay Def 32.7761 -117.2468
757022 Bullard et al. 2007 1997 Pillar Point Harbor, Half Moon Bay Def 37.5005 -122.4850
757023 Wasson et al. 2001; USGS Woods Hole Science Center 2007 1998 1998-04-30 Elkhorn Slough Station 6 (Whistlestop Lagoon) Def 36.8230 -121.7417
757024 Bullard et al. 2007 2001 Humboldt Bay Def 40.7864 -124.1922
757025 USGS Woods Hole Science Center 2007 2004 Woodley Island Marina Def 40.8078 -124.1612
757026 USGS Woods Hole Science Center 2007 2005 Woodley Island Marina Def 40.8078 -124.1612
757027 USGS Woods Hole Science Center 2007 2005 Woodley Island Marina Def 40.8078 -124.1612
757028 USGS Woods Hole Science Center 2012 2004 2004-05-23 Fisherman's Wharf, San Francisco Bay Def 37.8095 -122.4195
757029 Stefaniak et al. 2009; USGS Woods Hole Science Center 2012 2003 2003-05-28 Cass' Marina, Sausalito Def 37.8633 -122.4850
757030 Stefaniak et al. 2009; USGS Woods Hole Science Center 2012 2003 2003-05-30 Spud Point Marina, Bodega Bay Def 38.3300 -123.0583
757031 Lambert 2009 2003 Tomales Bay Def 38.2100 -122.9400
757032 Lambert 2005 2003 Kuiper Oyster Raft, Humboldt Bay Def 40.8722 -124.1490
757033 USGS Woods Hole Science Center 2012 2004 2004-05-25 Presidio Yacht Club, Horseshoe Bay (Sausalito) Def 37.8327 -122.4744
757034 de Rivera et al. 2005 2003 Moss Landing, North Def 36.8136 -121.7878
757035 de Rivera et al. 2005 2003 Moss Landing, South Def 36.8016 -121.7853
757036 de Rivera et al. 2005 2004 Mason's Marina Def 38.3321 -123.0588
757037 de Rivera et al. 2005a 2004 Clark Def 38.1810 -122.9105
757038 de Rivera et al. 2005a 2004 Miller Park Def 38.1996 -122.9217
757039 de Rivera et al. 2005a 2004 Thomas Station Def 38.1287 -122.8654
757040 Stefaniak et al. 2009 2007 2007-02-09 Catamaran Resort Hotel Dock, Mission Bay Def 32.7888 -117.2512
757041 G. Lambert and C. Lambert, unpublished observation, cited in Lambert 2009 1997 Mission Bay Def 32.7791 -117.2288
757042 Lambert 2009 1998 Mission Bay Def 32.7791 -117.2288
767369 Ruiz et al., 2015 2012 2012-08-22 Tomales-Marshall, Bodega Bay, California, USA Def 38.1514 -122.8888
767380 Ruiz et al., 2015 2012 2012-08-21 Tomales-Nick's Cove, Bodega Bay, California, USA Def 38.1980 -122.9222
767400 Ruiz et al., 2015 2012 2012-08-16 Tomales-SNPS, Bodega Bay, California, USA Def 38.1359 -122.8719
767412 Ruiz et al., 2015 2012 2012-08-17 Tomales- Shell Beach, Bodega Bay, California, USA Def 38.1163 -122.8713
767425 Ruiz et al., 2015 2013 2013-07-19 SeaWorld Marina, Mission Bay, CA, California, USA Def 32.7676 -117.2314
767461 Ruiz et al., 2015 2013 2013-07-29 Mission Bay Yacht Club, Mission Bay, CA, California, USA Def 32.7778 -117.2485
767527 Ruiz et al., 2015 2013 2013-08-03 Mission Bay Sport Center, Mission Bay, CA, California, USA Def 32.7857 -117.2495
767567 Ruiz et al., 2015 2013 2013-08-05 Paradise Point Resort, Mission Bay, CA, California, USA Def 32.7730 -117.2406
767581 Ruiz et al., 2015 2013 2013-08-30 201 Main, Morro Bay, CA, California, USA Def 35.3564 -120.8474
767592 Ruiz et al., 2015 2013 2013-08-27 City Harbor, Morro Bay, CA, California, USA Def 35.3709 -120.8582
767606 Ruiz et al., 2015 2013 2013-09-05 Launch Ramp, Morro Bay, CA, California, USA Def 35.3577 -120.8508
767614 Ruiz et al., 2015 2013 2013-08-29 Moorings, Morro Bay, CA, California, USA Def 35.3619 -120.8548
767627 Ruiz et al., 2015 2013 2013-08-31 Morro Bay Marina, Morro Bay, CA, California, USA Def 35.3641 -120.8532
767634 Ruiz et al., 2015 2013 2013-08-28 Sealion Dock, Morro Bay, CA, California, USA Def 35.3658 -120.8555
767645 Ruiz et al., 2015 2013 2013-09-03 State Park Marina, Morro Bay, CA, California, USA Def 35.3459 -120.8423
767657 Ruiz et al., 2015 2013 2013-09-04 Tidelands, Morro Bay, CA, California, USA Def 35.3602 -120.8521
767669 Ruiz et al., 2015 2013 2013-07-16 Naval Base Point Loma, San Diego Bay, CA, California, USA Def 32.6886 -117.2343
767682 Ruiz et al., 2015 2013 2013-07-17 Naval Station San Diego, San Diego Bay, CA, California, USA Def 32.6867 -117.1333
767708 Ruiz et al., 2015 2013 2013-07-25 Navy Ammo Dock, Pier Bravo, San Diego Bay, CA, California, USA Def 32.6939 -117.2276
767990 Ruiz et al., 2015 2012 2012-08-24 Richmond Marina Bay Yacht Harbor, San Francisco Bay, CA, California, USA Def 37.9134 -122.3523
768010 Ruiz et al., 2015 2012 2012-08-23 Sausalito Marine Harbor, San Francisco Bay, CA, California, USA Def 37.8609 -122.4853
768025 Ruiz et al., 2015 2012 2012-08-28 San Francisco Marina, San Francisco Bay, CA, California, USA Def 37.8071 -122.4341
768043 Ruiz et al., 2015 2012 2012-08-27 Port of San Francisco Pier 31, San Francisco Bay, CA, California, USA Def 37.8078 -122.4060
768066 Ruiz et al., 2015 2012 2012-09-11 Ballena Isle Marina, San Francisco Bay, CA, California, USA Def 37.7676 -122.2869
768089 Ruiz et al., 2015 2012 2012-08-30 Oyster Point Marina, San Francisco Bay, CA, California, USA Def 37.6633 -122.3817
768113 Ruiz et al., 2015 2012 2012-08-29 Coyote Point Marina, San Francisco Bay, CA, California, USA Def 37.5877 -122.3174
768135 Ruiz et al., 2015 2012 2012-09-04 Redwood City Marina, San Francisco Bay, CA, California, USA Def 37.5023 -122.2130
768179 Ruiz et al., 2015 2012 2012-09-05 Port of Oakland, San Francisco Bay, CA, California, USA Def 37.7987 -122.3228
768199 Ruiz et al., 2015 2012 2012-09-07 Jack London Square Marina, San Francisco Bay, CA, California, USA Def 37.7940 -122.2787
768237 Ruiz et al., 2015 2012 2012-09-13 San Leandro Marina, San Francisco Bay, CA, California, USA Def 37.6962 -122.1919
768301 Ruiz et al., 2015 2013 2013-08-20 Coyote Point Marina, San Francisco Bay, CA, California, USA Def 37.5877 -122.3163
768361 Ruiz et al., 2015 2013 2013-08-13 Oyster Point Marina, San Francisco Bay, CA, California, USA Def 37.6639 -122.3821
768405 Ruiz et al., 2015 2013 2013-08-19 Richmond Marina Bay Yacht Harbor, San Francisco Bay, CA, California, USA Def 37.9138 -122.3522
768422 Ruiz et al., 2015 2013 2013-08-12 San Francisco Marina, San Francisco Bay, CA, California, USA Def 37.8078 -122.4354
768435 Ruiz et al., 2015 2013 2013-08-21 San Leandro Marina, San Francisco Bay, CA, California, USA Def 37.6980 -122.1908
768453 Ruiz et al., 2015 2013 2013-08-16 Sausalito Marine Harbor, San Francisco Bay, CA, California, USA Def 37.8611 -122.4851
771804 Ruiz et al., 2021a 2018 2018-09-17 San Francisco Marina, San Francisco Bay, California, USA Def 37.8065 -122.4412
771824 Ruiz et al., 2021a 2018 2018-09-17 San Francisco Marina, San Francisco Bay, California, USA Def 37.8065 -122.4412
773910 Ruiz et al., 2022 2014 2014-09-08 San Francisco Marina, San Francisco Bay, California, USA Def 37.8078 -122.4354
773911 Ruiz et al., 2022 2014 2014-09-08 San Francisco Marina, San Francisco Bay, California, USA Def 37.8078 -122.4354
773912 Ruiz et al., 2022 2014 2014-09-08 San Francisco Marina, San Francisco Bay, California, USA Def 37.8078 -122.4354
773913 Ruiz et al., 2022 2014 2014-09-08 San Francisco Marina, San Francisco Bay, California, USA Def 37.8078 -122.4354
773914 Ruiz et al., 2022 2014 2014-09-08 San Francisco Marina, San Francisco Bay, California, USA Def 37.8078 -122.4354
773915 Ruiz et al., 2022 2014 2014-09-08 San Francisco Marina, San Francisco Bay, California, USA Def 37.8078 -122.4354
773916 Ruiz et al., 2022 2014 2014-09-08 San Francisco Marina, San Francisco Bay, California, USA Def 37.8078 -122.4354
773917 Ruiz et al., 2022 2014 2014-09-08 San Francisco Marina, San Francisco Bay, California, USA Def 37.8078 -122.4354
773918 Ruiz et al., 2022 2014 2014-09-08 San Francisco Marina, San Francisco Bay, California, USA Def 37.8078 -122.4354
773919 Ruiz et al., 2022 2014 2014-09-09 San Leandro Marina, San Francisco Bay, California, USA Def 37.6978 -122.1928
773920 Ruiz et al., 2022 2014 2014-09-09 San Leandro Marina, San Francisco Bay, California, USA Def 37.6978 -122.1928
773921 Ruiz et al., 2022 2014 2014-09-09 San Leandro Marina, San Francisco Bay, California, USA Def 37.6978 -122.1928
773922 Ruiz et al., 2022 2014 2014-09-19 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4851
773923 Ruiz et al., 2022 2014 2014-09-19 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4851
773924 Ruiz et al., 2022 2014 2014-09-19 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4851
773925 Ruiz et al., 2022 2014 2014-09-19 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4851
773926 Ruiz et al., 2022 2014 2014-09-19 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4851
773927 Ruiz et al., 2022 2014 2014-09-19 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4851
773928 Ruiz et al., 2022 2014 2014-09-19 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4851
773929 Ruiz et al., 2022 2014 2014-09-19 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4851
773930 Ruiz et al., 2022 2014 2014-09-19 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4851
773931 Ruiz et al., 2022 2014 2014-09-19 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4851
773932 Ruiz et al., 2022 2014 2014-09-16 Coyote Point Marina, San Francisco Bay, California, USA Def 37.5895 -122.3160
773933 Ruiz et al., 2022 2014 2014-09-16 Coyote Point Marina, San Francisco Bay, California, USA Def 37.5895 -122.3160
773934 Ruiz et al., 2022 2014 2014-09-16 Coyote Point Marina, San Francisco Bay, California, USA Def 37.5895 -122.3160
773935 Ruiz et al., 2022 2014 2014-09-16 Coyote Point Marina, San Francisco Bay, California, USA Def 37.5895 -122.3160
773936 Ruiz et al., 2022 2014 2014-09-16 Coyote Point Marina, San Francisco Bay, California, USA Def 37.5895 -122.3160
773937 Ruiz et al., 2022 2014 2014-09-16 Coyote Point Marina, San Francisco Bay, California, USA Def 37.5895 -122.3160
773938 Ruiz et al., 2022 2014 2014-09-16 Coyote Point Marina, San Francisco Bay, California, USA Def 37.5895 -122.3160
773939 Ruiz et al., 2022 2014 2014-09-17 Oyster Point Marina, San Francisco Bay, California, USA Def 37.6639 -122.3758
773940 Ruiz et al., 2022 2014 2014-09-11 Redwood City Marina, San Francisco Bay, California, USA Def 37.5024 -122.2134
773941 Ruiz et al., 2022 2014 2014-09-12 Ballena Isle Marina, San Francisco Bay, California, USA Def 37.7662 -122.2656
773942 Ruiz et al., 2022 2014 2014-09-12 Ballena Isle Marina, San Francisco Bay, California, USA Def 37.7662 -122.2656
773943 Ruiz et al., 2022 2014 2014-09-12 Ballena Isle Marina, San Francisco Bay, California, USA Def 37.7662 -122.2656
773944 Ruiz et al., 2022 2014 2014-09-12 Ballena Isle Marina, San Francisco Bay, California, USA Def 37.7662 -122.2656
773945 Ruiz et al., 2022 2014 2014-09-12 Ballena Isle Marina, San Francisco Bay, California, USA Def 37.7662 -122.2656
773946 Ruiz et al., 2022 2014 2014-09-10 Richmond Marina Bay Yacht Harbor, San Francisco Bay, California, USA Def 37.9138 -122.3522
773947 Ruiz et al., 2022 2014 2014-09-10 Richmond Marina Bay Yacht Harbor, San Francisco Bay, California, USA Def 37.9138 -122.3522
773948 Ruiz et al., 2022 2014 2014-09-10 Richmond Marina Bay Yacht Harbor, San Francisco Bay, California, USA Def 37.9138 -122.3522
773949 Ruiz et al., 2022 2014 2014-09-10 Richmond Marina Bay Yacht Harbor, San Francisco Bay, California, USA Def 37.9138 -122.3522
773950 Ruiz et al., 2022 2014 2014-09-10 Richmond Marina Bay Yacht Harbor, San Francisco Bay, California, USA Def 37.9138 -122.3522
773951 Ruiz et al., 2022 2014 2014-09-10 Richmond Marina Bay Yacht Harbor, San Francisco Bay, California, USA Def 37.9138 -122.3522
773952 Ruiz et al., 2022 2014 2014-09-10 Richmond Marina Bay Yacht Harbor, San Francisco Bay, California, USA Def 37.9138 -122.3522
773953 Ruiz et al., 2022 2014 2014-09-10 Richmond Marina Bay Yacht Harbor, San Francisco Bay, California, USA Def 37.9138 -122.3522
773954 Ruiz et al., 2022 2014 2014-09-10 Richmond Marina Bay Yacht Harbor, San Francisco Bay, California, USA Def 37.9138 -122.3522
773955 Ruiz et al., 2022 2014 2014-09-10 Richmond Marina Bay Yacht Harbor, San Francisco Bay, California, USA Def 37.9138 -122.3522
773956 Ruiz et al., 2022 2014 2014-09-15 Loch Lomond Marina, San Francisco Bay, California, USA Def 37.9723 -122.4829
773957 Ruiz et al., 2022 2015 2015-09-23 Oyster Point Marina, San Francisco Bay, California, USA Def 37.6630 -122.3798
773958 Ruiz et al., 2022 2015 2015-09-22 Coyote Point Marina, San Francisco Bay, California, USA Def 37.5887 -122.3164
773959 Ruiz et al., 2022 2015 2015-09-22 Coyote Point Marina, San Francisco Bay, California, USA Def 37.5887 -122.3164
773960 Ruiz et al., 2022 2015 2015-09-22 Coyote Point Marina, San Francisco Bay, California, USA Def 37.5887 -122.3164
773961 Ruiz et al., 2022 2015 2015-09-18 Loch Lomond Marina, San Francisco Bay, California, USA Def 37.9731 -122.4827
773962 Ruiz et al., 2022 2015 2015-09-25 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4849
773963 Ruiz et al., 2022 2015 2015-09-25 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4849
773964 Ruiz et al., 2022 2015 2015-09-25 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4849
773965 Ruiz et al., 2022 2015 2015-09-25 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4849
773966 Ruiz et al., 2022 2015 2015-09-25 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4849
773967 Ruiz et al., 2022 2015 2015-09-25 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4849
773968 Ruiz et al., 2022 2015 2015-09-25 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4849
773969 Ruiz et al., 2022 2015 2015-09-25 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8612 -122.4849
773970 Ruiz et al., 2022 2016 2016-09-23 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8606 -122.4853
773971 Ruiz et al., 2022 2016 2016-09-23 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8606 -122.4853
773972 Ruiz et al., 2022 2016 2016-09-23 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8606 -122.4853
773973 Ruiz et al., 2022 2016 2016-09-23 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8606 -122.4853
773974 Ruiz et al., 2022 2016 2016-09-23 Sausalito Marine Harbor, San Francisco Bay, California, USA Def 37.8606 -122.4853
773975 Ruiz et al., 2022 2016 2016-09-22 Coyote Point Marina, San Francisco Bay, California, USA Def 37.5898 -122.3165
773976 Ruiz et al., 2022 2016 2016-09-22 Coyote Point Marina, San Francisco Bay, California, USA Def 37.5898 -122.3165
773977 Ruiz et al., 2022 2016 2016-09-22 Coyote Point Marina, San Francisco Bay, California, USA Def 37.5898 -122.3165
773978 Ruiz et al., 2022 2016 2016-09-12 Richmond Marina Bay Yacht Harbor, San Francisco Bay, California, USA Def 37.9133 -122.3500
773979 Ruiz et al., 2022 2016 2016-09-13 Ballena Isle Marina, San Francisco Bay, California, USA Def 37.7679 -122.2863
773980 Ruiz et al., 2022 2016 2016-09-14 San Leandro Marina, San Francisco Bay, California, USA Def 37.6978 -122.1928

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