Invasion History
First Non-native North American Tidal Record: 1893First Non-native West Coast Tidal Record: 1893
First Non-native East/Gulf Coast Tidal Record:
General Invasion History:
Gemma gemma is native to the northwest Atlantic from southern Labrador to Venezuela, including the Bahamas, Cuba, Puerto Rico, and the Virgin Islands (Bousfield 1960; Abbott 1974; Linero Arana and Mata 2003; Florida Museum of Natural History 2012; Rosenberg 2012). Abbott (1974) attributes occurrences on the West Indian Islands to dispersal by migratory birds. Gemma gemma was first found outside its native range in the digestive system of a wild duck sold at a San Francisco market in 1893, and was found to be established in San Francisco Bay (Carlton 1979). It was very likely introduced with plantings of Eastern Oysters (Crassostrea virginica). Reports from Puget Sound and British Columbia resulted from confusion with a native clam Transenella tantilla. Its current range is from Elkhorn Slough, California (CA) to Humboldt Bay, CA (Carlton 1992, Boyd et al. 2002).
North American Invasion History:
Invasion History on the West Coast:
As noted above, Gemma gemma was first found on the West Coast, in the crop of a wild duck, very likely shot in a marsh around San Francisco Bay (Carlton 1979). It was found to be abundant on the ‘East Bay shore’ (Stearns 1899, cited by Carlton 1979). In San Francisco, it is found in Suisun and San Pablo Bays, but is especially abundant on the mudflats of the South Bay, where abundances have exceeded 400,000 m-3 (Nichols and Thompson 1985; Cohen and Carlton 1995). In their 2004 survey, Cohen et al. (2005) collected it at Coyote Point Marina on the South Bay (Cohen et al. 2005).
Outside San Francisco Bay it was collected in Bolinas Lagoon in 1918, Tomales Bay and Elkhorn Slough in 1965 (Johnson and Juskevice 1965, cited by Carlton 1979; MacDonald 1969) and Bodega Harbor in 1974 (Standing 1975, cited by Carlton 1979). It was initially reported as rare in Bodega Harbor, but became very abundant after 1995, apparently because larger, competing native clams (Nutricola sp.) were preyed upon by the newly introduced Green Crab (Carcinus maenas), as shown in feeding experiments (Grosholz 1995). The range of G. gemma in Bodega Harbor has increased since 1995 from three to all five of a set of long-term sampling stations (Grosholz 2005). This clam was found in Humboldt Bay by 1992, and was abundant and widespread by 2002 (Barnhart et al. 1992, cited by Boyd et al. 2002). Genetic analysis indicates that multiple introductions of G. gemma have occurred in San Francisco Bay, with sorting of genotypes over time. The introductions of this clam to Tomales Bay and Bodega Harbor have probably been separate and independent of its introduction to San Francisco Bay (Hoos et al. 2010).
Description
Gemma gemma is a small clam, reaching 3-5 mm in length, with a rounded triangular shape which is moderately inflated. Its shell is rather thin and is polished on the exterior with numerous fine concentric furrows. The color is whitish to tan with a purplish wash over the beak and posterior areas. The pallial sinus is variable, but often about the length of the posterior muscle scar, and points upward towards the beak. The inner margin of the shell has fine crenulations, which are visible with a hand lens (Abbott 1974; Gosner 1978; Coan et al. 2000; Coan and Valentich-Scott, in Carlton 2007).
Taxonomy
Taxonomic Tree
Kingdom: | Animalia | |
Phylum: | Mollusca | |
Class: | Bivalvia | |
Subclass: | Heterodonta | |
Order: | Veneroida | |
Superfamily: | Veneroidea | |
Family: | Veneridae | |
Genus: | Gemma | |
Species: | gemma |
Synonyms
Gemma pupurea (Lea, 1842)
Potentially Misidentified Species
This native northeast Pacific clam (as Transennella tantilla) was often confused with Gemma gemma (Narchi 1971; Carlton 1979).
Ecology
General:
Gemma gemma is a small burrowing clam (< 5 mm) which inhabits muddy-sandy tidal flats. Sexes are probably separate (Narchi 1971). Eggs and larvae are brooded in the female's gills and are released as miniature non-pelagic clams at 340-390 mm (Chanley and Andrews 1971). Up to 100 eggs are produced (Green and Hobson 1970). In Maine, juveniles were released mostly in July-August, but a few were released as late as February (Bradley and Cooke 1958), while in Venezuela, most breeding took place from September to March (Linero-Arana and Mata 2003). In San Francisco, females were found brooding in March-December, and many produced more than one brood per year (Thompson 1982). The young are dispersed with bottom waves and currents, together with sand and mud particles (termed 'bedload transport') (Thompson 1982). Juveniles can produce byssal threads to anchor themselves to surfaces or sand grains, but this ability is lost in the adults (Narchi 1971).
Gemma gemma inhabits muddy-to-sandy sediments in the intertidal and shallow subtidal zone (Bradley and Cooke 1958; Green and Hobson 1970). They tolerate salinities as low as 5 PSU as adults (with acclimation) and reproduce at salinities as low as 10 PSU (Castagna and Chanley 1973). However, population decreases in Little Narragansett Bay (Rhode Island-Connecticut), were associated with low spring salinities (March-June averages < 30 PSU, Weinberg 1985). This clam is tolerant of a wide range of temperatures, surviving near zero degrees in ice-covered regions at the northern end of its range (Bradley and Cooke 1958). In short-term experiments, G. gemma had an LC50 of 35°C (Kennedy and Mihursky 1971), while populations in a Venezuelan lagoon persisted at summer temperatures of 30°C, but were much more abundant in the cooler months (Linero Arana and Mata 2003). Gemma gemma is a filter-feeder on phytoplankton and other suspended particles. It is normally partially buried in the substrate, with the posterior part of the shell and siphons emerging (Bradley and Cooke 1958; Narchi 1971).
Food:
Phtyoplankton; Detritus
Consumers:
Waterfowl, fishes, crabs
Trophic Status:
Suspension Feeder
SusFedHabitats
General Habitat | Unstructured Bottom | None |
General Habitat | Oyster Reef | None |
Salinity Range | Mesohaline | 5-18 PSU |
Salinity Range | Polyhaline | 18-30 PSU |
Salinity Range | Euhaline | 30-40 PSU |
Tidal Range | Subtidal | None |
Tidal Range | Low Intertidal | None |
Vertical Habitat | Endobenthic | None |
Tolerances and Life History Parameters
Minimum Temperature (ºC) | -2 | Based on geographical range (Bousfield 1960) |
Maximum Temperature (ºC) | 37 | 24 hr LC 50, experimental, 30 C acclimation (Kennedy and Mihursky 1971) |
Minimum Salinity (‰) | 5 | Experimental (Chanley and Castagna 1978) |
Maximum Salinity (‰) | 35 | Field data (Miller 2000) |
Minimum Length (mm) | 1.8 | Minimum reprducitive size, Green and Hobson 1978 |
Maximum Length (mm) | 5 | Abbott 1974, Gosner 1978 |
Broad Temperature Range | None | Cold temperate-Subtropical |
Broad Salinity Range | None | Mesohaline-Euhaline |
General Impacts
Gemma gemma is a potential competitor with other small bivalves and with the juveniles of large bivalves. In Maine, native Gemma populations were studied as possible competitors to the Soft-Shell Clam (Mya arenaria), but field data and sediment cores indicated that Gemma was adversely affected by M. arenaria (Bradley and Cooke 1958).On the West Coast, G. gemma appears to compete with the small native clam Nutricola spp. (=Transennella tantilla) (Purple Dwarf-Venus) on the Pacific coast. Narchi (1971) and Carlton (1979) noted that G. gemma and Nutricola rarely co-occurred in San Francisco and Tomales Bays, although both could be very abundant. In Bodega Harbor, Nutricola was the superior competitor in experiments, but predation by the invasive Green Crab (Carcinus maenas) gave the smaller, faster-reproducing G. gemma an advantage over the somewhat larger (6-12 mm) native clam (Grosholz 2005).
Regional Impacts
P090 | San Francisco Bay | Ecological Impact | Competition | ||
Competition is suspected with Nutricola tantilla (=Transenella tantilla), rarely found together in the same samples (Carlton 1979). | |||||
P110 | Tomales Bay | Ecological Impact | Competition | ||
Competition is suspected with Nutricola tantilla (=Transennella tantilla), rarely found together in the same samples (Narchi 1971; Carlton 1979). | |||||
P112 | _CDA_P112 (Bodega Bay) | Ecological Impact | Competition | ||
In Bodega Harbor, G. gemma was rare, until the arrival of the invasive Green Crab (Carcinus maenas), which preferred the larger Nutricola spp. In experiments, Gemma grew slowly in the presence of abundant Nutricola, but grew and reproduced much faster when Nutricola was rare (Grosholz 2005). | |||||
NEP-V | Northern California to Mid Channel Islands | Ecological Impact | Competition | ||
In San Francisco and Tomales Bays, competition was suspected with Nutricola tantilla (=Transennella tantilla). The two species were rarely found together in the same samples (Narchi 1971; Carlton 1979). In Bodega Harbor, G. gemma was rare, until the arrival of the invasive Green Crab (Carcinus maenas), which preferred the larger Nutricola spp. In experiments, Gemma grew slowly in the presence of abundant Nutricola, but grew and reproduced much faster when Nutricola was rare (Grosholz 2005). | |||||
NEP-V | Northern California to Mid Channel Islands | Ecological Impact | Food/Prey | ||
Gemma gemma comprised 55% of food items of the shorebirds Avocet (Recurvirostra americana and Red Knot (Calidris canutus) surveyed in Palo Alto, San Francisco Bay (Recher 1963). | |||||
CA | California | Ecological Impact | Competition | ||
In San Francisco and Tomales Bays, competition was suspected with Nutricola tantilla (=Transennella tantilla). The two species were rarely found together in the same samples (Narchi 1971; Carlton 1979). In Bodega Harbor, G. gemma was rare, until the arrival of the invasive Green Crab (Carcinus maenas), which preferred the larger Nutricola spp. In experiments, Gemma grew slowly in the presence of abundant Nutricola, but grew and reproduced much faster when Nutricola was rare (Grosholz 2005)., Competition is suspected with Nutricola tantilla (=Transenella tantilla), rarely found together in the same samples (Carlton 1979)., Competition is suspected with Nutricola tantilla (=Transennella tantilla), rarely found together in the same samples (Narchi 1971; Carlton 1979)., In Bodega Harbor, G. gemma was rare, until the arrival of the invasive Green Crab (Carcinus maenas), which preferred the larger Nutricola spp. In experiments, Gemma grew slowly in the presence of abundant Nutricola, but grew and reproduced much faster when Nutricola was rare (Grosholz 2005). | |||||
CA | California | Ecological Impact | Food/Prey | ||
Gemma gemma comprised 55% of food items of the shorebirds Avocet (Recurvirostra americana and Red Knot (Calidris canutus) surveyed in Palo Alto, San Francisco Bay (Recher 1963). |
Regional Distribution Map
Bioregion | Region Name | Year | Invasion Status | Population Status |
---|---|---|---|---|
NEP-IV | Puget Sound to Northern California | 1992 | Non-native | Established |
P130 | Humboldt Bay | 1992 | Non-native | Established |
P112 | _CDA_P112 (Bodega Bay) | 1974 | Non-native | Established |
P110 | Tomales Bay | 1965 | Non-native | Established |
P080 | Monterey Bay | 1965 | Non-native | Established |
P095 | _CDA_P095 (Tomales-Drakes Bay) | 1918 | Non-native | Established |
P093 | _CDA_P093 (San Pablo Bay) | 1899 | Non-native | Established |
P090 | San Francisco Bay | 1893 | Non-native | Established |
NEP-V | Northern California to Mid Channel Islands | 1893 | Non-native | Established |
Occurrence Map
OCC_ID | Author | Year | Date | Locality | Status | Latitude | Longitude |
---|---|---|---|---|---|---|---|
697116 | Wasson et al. 2001 (Elkhorn Slough Survey) | 1998 | Elkhorn Slough Station 9 (Kirby Park) | Non-native | 36.8398 | -121.7435 | |
697454 | Boyd et al. 2002 (Humboldt Bay Report) | 2002 | Mad River Slough - Samoa Blvd. Bridge | Non-native | 40.8652 | -124.1505 | |
697501 | Boyd et al. 2002 (Humboldt Bay Report) | 2002 | Klopp Lake | Non-native | 40.8553 | -124.0919 | |
697548 | Introduced Species Study | 2003 | 2003-08-27 | Loch Lomond 2 | Non-native | 37.9717 | -122.4811 |
698030 | Wasson et al. 2001 (Elkhorn Slough Survey) | 1998 | Elkhorn Slough Station 10 (Hudson's Langind) | Non-native | 36.8578 | -121.7572 | |
698615 | Cohen et al. 2005 (SF Bay Area RAS) | 2004 | 2004-05-27 | Coyote Point Marina, San Francisco Bay | Non-native | 37.5907 | -122.3180 |
699418 | Introduced Species Study | 2010 | 2010-06-13 | Coyote Point | Non-native | 37.5920 | -122.3210 |
699750 | Introduced Species Study | 2010 | 2010-06-14 | Aquatic Park | Non-native | 37.8080 | -122.4216 |
699846 | Introduced Species Study | 2005 | 2005-06-09 | Paradise Area | Non-native | 37.9062 | -122.4768 |
700126 | Wasson et al. 2001 (Elkhorn Slough Survey) | 1998 | Elkhorn Slough Station 5 (South Marsh Trail) | Non-native | 36.8193 | -121.7378 | |
700525 | Introduced Species Study | 2005 | 2005-06-08 | Sea Plane Lagoon | Non-native | 37.7761 | -122.2998 |
700916 | Nichols & Thompson 1985a, 1985b | 1985 | South San Francisco Bay | Non-native | 37.5457 | -122.1645 | |
701260 | Stearns 1899 | 1899 | "Alameda flats" (off Oakland) | Non-native | 37.7521 | -122.2643 | |
701261 | Carlton 1979 | 1893 | San Francisco Bay | Non-native | 37.8494 | -122.3681 | |
701455 | Introduced Species Study | 2010 | 2010-06-30 | Hercules Wharf | Non-native | 38.0231 | -122.2928 |
701460 | Introduced Species Study | 2005 | 2005-10-19 | Hercules Wharf | Non-native | 38.0231 | -122.2928 |
701804 | Carlton 1979 | 1918 | Bolinas Lagoon | Non-native | 37.9189 | -122.6816 | |
702787 | Nichols & Thompson 1985a, 1985b | 1985 | Central San Francisco Bay | Non-native | 37.8595 | -122.3884 | |
703155 | Boyd et al. 2002 (Humboldt Bay Report) | 2002 | Mad River Slough - Lanphere Christianson Dunes Bridge | Non-native | 40.8979 | -124.1356 | |
703598 | Introduced Species Study | 2005 | 2005-06-10 | Toll Plaza | Non-native | 37.8266 | -122.3166 |
703775 | Introduced Species Study | 2005 | 2005-06-08 | Crown Beach | Non-native | 37.7603 | -122.2737 |
703804 | Introduced Species Study | 2005 | 2005-06-10 | Hayward Landing | Non-native | 37.6447 | -122.1543 |
703805 | Introduced Species Study | 2010 | 2010-06-13 | Hayward Landing | Non-native | 37.6447 | -122.1543 |
704087 | Nichols & Thompson 1985a, 1985b | 1985 | San Pablo Bay | Non-native | 38.0600 | -122.3900 | |
714209 | Barnhart et al. 1992 | 1992 | Humboldt Bay | Non-native | 40.7500 | -124.2083 | |
759628 | Packard 1918 | 1913 | South San Francisco Bay | Non-native | 37.5457 | -122.1645 | |
759629 | Packard 1918 | 1913 | Central San Francisco Bay | Non-native | 37.8595 | -122.3884 | |
759630 | Packard 1918 | 1913 | Sausalito vicinity | Non-native | 37.8595 | -122.4771 | |
759631 | Light 1969 | 1967 | Bolinas Lagoon | Non-native | 37.9189 | -122.6816 | |
759632 | Shulenberger 1970 | 1969 | 1969-07-31 | Walker Creek, Tomales Bay | Non-native | 38.2111 | -122.9317 |
759633 | Wicksten 1978 | 1973 | Coyote Point | Non-native | 37.5906 | -122.3169 | |
759634 | Chapman and Dorman 1975 | 1971 | Bolinas Lagoon | Non-native | 37.9189 | -122.6816 | |
759635 | Chapman and Dorman 1975 | 1971 | 1971-02-20 | Pinole Point | Non-native | 38.0133 | -122.3659 |
759636 | Heiman and Micheli 2010; Hobbs et al. 2015 | 2002 | Elkhorn Slough (Upper) | Non-native | 36.8547 | -121.7600 | |
759637 | Recher 1966 | 1962 | near Mouth of San Francisquito Creek | Non-native | 37.4658 | -122.1156 | |
759638 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 11 (16-18') | Non-native | 38.0169 | -122.4258 | |
759639 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 11 (16-18') | Non-native | 38.0169 | -122.4258 | |
759640 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 11 (16-18') | Non-native | 38.0169 | -122.4258 | |
759641 | Painter 1966b; Hopkins 1986 | 1973 | Carquinez Strait, Station 3 (Deep; off Commodore Jones Point) | Non-native | 38.0542 | -122.1756 | |
759642 | Painter 1966b; Hopkins 1986 | 1973 | Carquinez Strait, Station 23 (6-8') | Non-native | 38.0547 | -122.1744 | |
759643 | Painter 1966b; Hopkins 1986 | 1973 | Carquinez Strait, Station 23 (6-8') | Non-native | 38.0547 | -122.1744 | |
759644 | Painter 1966b; Hopkins 1986 | 1973 | Carquinez Strait, Station 23 (6-8') | Non-native | 38.0547 | -122.1744 | |
759645 | Painter 1966b; Hopkins 1986 | 1973 | Carquinez Strait, Station 23 (6-8') | Non-native | 38.0547 | -122.1744 | |
759646 | Painter 1966b; Hopkins 1986 | 1973 | Carquinez Strait, Station 23 (6-8') | Non-native | 38.0547 | -122.1744 | |
759647 | Painter 1966b; Hopkins 1986 | 1973 | Carquinez Strait, Station 23 (6-8') | Non-native | 38.0547 | -122.1744 | |
759648 | Painter 1966b; Hopkins 1986 | 1973 | Suisun Bay, near Point Edith, Station 4 (Deep) | Non-native | 38.0567 | -122.0744 | |
759649 | Painter 1966b; Hopkins 1986 | 1973 | Suisun Bay, near Point Edith, Station 14 (16-18') | Non-native | 38.0597 | -122.0764 | |
759650 | Painter 1966b; Hopkins 1986 | 1973 | Suisun Bay, near Point Edith, Station 24 (6-8') | Non-native | 38.0606 | -122.0769 | |
759651 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 31 (Intertidal) | Non-native | 38.0833 | -122.4797 | |
759652 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 31 (Intertidal) | Non-native | 38.0833 | -122.4797 | |
759653 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 31 (Intertidal) | Non-native | 38.0833 | -122.4797 | |
759654 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 31 (Intertidal) | Non-native | 38.0833 | -122.4797 | |
759655 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 31 (Intertidal) | Non-native | 38.0833 | -122.4797 | |
759656 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 31 (Intertidal) | Non-native | 38.0833 | -122.4797 | |
759657 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 31 (Intertidal) | Non-native | 38.0833 | -122.4797 | |
759658 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 31 (Intertidal) | Non-native | 38.0833 | -122.4797 | |
759659 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 31 (Intertidal) | Non-native | 38.0833 | -122.4797 | |
759660 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 31 (Intertidal) | Non-native | 38.0833 | -122.4797 | |
759661 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 31 (Intertidal) | Non-native | 38.0833 | -122.4797 | |
759662 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 21 (6-8') | Non-native | 38.0889 | -122.4636 | |
759663 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 21 (6-8') | Non-native | 38.0889 | -122.4636 | |
759664 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 21 (6-8') | Non-native | 38.0889 | -122.4636 | |
759665 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 21 (6-8') | Non-native | 38.0889 | -122.4636 | |
759666 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 21 (6-8') | Non-native | 38.0889 | -122.4636 | |
759667 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 21 (6-8') | Non-native | 38.0889 | -122.4636 | |
759668 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 21 (6-8') | Non-native | 38.0889 | -122.4636 | |
759669 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 21 (6-8') | Non-native | 38.0889 | -122.4636 | |
759670 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 21 (6-8') | Non-native | 38.0889 | -122.4636 | |
759671 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 21 (6-8') | Non-native | 38.0889 | -122.4636 | |
759672 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 21 (6-8') | Non-native | 38.0889 | -122.4636 | |
759673 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay West, Station 21 (6-8') | Non-native | 38.0889 | -122.4636 | |
759674 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 22 (6-8') | Non-native | 38.0900 | -122.3569 | |
759675 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 22 (6-8') | Non-native | 38.0900 | -122.3569 | |
759676 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 22 (6-8') | Non-native | 38.0900 | -122.3569 | |
759677 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 22 (6-8') | Non-native | 38.0900 | -122.3569 | |
759678 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 22 (6-8') | Non-native | 38.0900 | -122.3569 | |
759679 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 22 (6-8') | Non-native | 38.0900 | -122.3569 | |
759680 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 22 (6-8') | Non-native | 38.0900 | -122.3569 | |
759681 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 22 (6-8') | Non-native | 38.0900 | -122.3569 | |
759682 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 32 (Intertidal) | Non-native | 38.1261 | -122.3544 | |
759683 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 32 (Intertidal) | Non-native | 38.1261 | -122.3544 | |
759684 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 32 (Intertidal) | Non-native | 38.1261 | -122.3544 | |
759685 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 32 (Intertidal) | Non-native | 38.1261 | -122.3544 | |
759686 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 32 (Intertidal) | Non-native | 38.1261 | -122.3544 | |
759687 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 32 (Intertidal) | Non-native | 38.1261 | -122.3544 | |
759688 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 32 (Intertidal) | Non-native | 38.1261 | -122.3544 | |
759689 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 32 (Intertidal) | Non-native | 38.1261 | -122.3544 | |
759690 | Painter 1966b; Hopkins 1986 | 1973 | San Pablo Bay East, Station 32 (Intertidal) | Non-native | 38.1261 | -122.3544 | |
759691 | Jones 1961; Hopkins 1986 | 1955 | 1955-01-15 | Point Richmond, Station A | Non-native | 37.9211 | -122.3881 |
759692 | Jones 1961; Hopkins 1986 | 1955 | 1955-03-06 | Point Richmond, Station A | Non-native | 37.9211 | -122.3881 |
759693 | Jones 1961; Hopkins 1986 | 1955 | 1955-04-16 | Point Richmond, Station A | Non-native | 37.9211 | -122.3881 |
759694 | Jones 1961; Hopkins 1986 | 1955 | 1955-07-09 | Point Richmond, Station A | Non-native | 37.9211 | -122.3881 |
759695 | Jones 1961; Hopkins 1986 | 1956 | 1956-01-24 | Point Richmond, Station A | Non-native | 37.9211 | -122.3881 |
759696 | Jones 1961; Hopkins 1986 | 1956 | 1956-03-17 | Point Richmond, Station A | Non-native | 37.9211 | -122.3881 |
759697 | Jones 1961; Hopkins 1986 | 1955 | 1955-01-15 | Point Richmond, Station B | Non-native | 37.9114 | -122.3889 |
759698 | Jones 1961; Hopkins 1986 | 1955 | 1955-03-16 | Point Richmond, Station B | Non-native | 37.9114 | -122.3889 |
759699 | Jones 1961; Hopkins 1986 | 1955 | 1955-10-22 | Point Richmond, Station B | Non-native | 37.9114 | -122.3889 |
759700 | Jones 1961; Hopkins 1986 | 1955 | 1955-01-29 | Point Richmond, Station C | Non-native | 37.9036 | -122.3853 |
759701 | Jones 1961; Hopkins 1986 | 1955 | 1955-03-06 | Point Richmond, Station C | Non-native | 37.9036 | -122.3853 |
759702 | Jones 1961; Hopkins 1986 | 1955 | 1955-04-16 | Point Richmond, Station C | Non-native | 37.9036 | -122.3853 |
759703 | Jones 1961; Hopkins 1986 | 1955 | 1955-05-28 | Point Richmond, Station C | Non-native | 37.9036 | -122.3853 |
759704 | Jones 1961; Hopkins 1986 | 1955 | 1955-07-09 | Point Richmond, Station C | Non-native | 37.9036 | -122.3853 |
759705 | Jones 1961; Hopkins 1986 | 1955 | 1955-09-15 | Point Richmond, Station C | Non-native | 37.9036 | -122.3853 |
759706 | Jones 1961; Hopkins 1986 | 1955 | 1955-10-22 | Point Richmond, Station C | Non-native | 37.9036 | -122.3853 |
759707 | Jones 1961; Hopkins 1986 | 1955 | 1955-11-26 | Point Richmond, Station C | Non-native | 37.9036 | -122.3853 |
759708 | Jones 1961; Hopkins 1986 | 1956 | 1956-01-24 | Point Richmond, Station C | Non-native | 37.9036 | -122.3853 |
759709 | Jones 1961; Hopkins 1986 | 1956 | 1956-03-17 | Point Richmond, Station C | Non-native | 37.9036 | -122.3853 |
759710 | Jones 1961; Hopkins 1986 | 1955 | 1955-01-29 | Point Richmond, Station D | Non-native | 37.9058 | -122.3850 |
759711 | Jones 1961; Hopkins 1986 | 1955 | 1955-03-06 | Point Richmond, Station D | Non-native | 37.9058 | -122.3850 |
759712 | Jones 1961; Hopkins 1986 | 1955 | 1955-04-16 | Point Richmond, Station D | Non-native | 37.9058 | -122.3850 |
759713 | Jones 1961; Hopkins 1986 | 1955 | 1955-05-28 | Point Richmond, Station D | Non-native | 37.9058 | -122.3850 |
759714 | Jones 1961; Hopkins 1986 | 1955 | 1955-07-09 | Point Richmond, Station D | Non-native | 37.9058 | -122.3850 |
759715 | Jones 1961; Hopkins 1986 | 1955 | 1955-09-15 | Point Richmond, Station D | Non-native | 37.9058 | -122.3850 |
759716 | Jones 1961; Hopkins 1986 | 1955 | 1955-10-22 | Point Richmond, Station D | Non-native | 37.9058 | -122.3850 |
759717 | Jones 1961; Hopkins 1986 | 1955 | 1955-11-26 | Point Richmond, Station D | Non-native | 37.9058 | -122.3850 |
759718 | Jones 1961; Hopkins 1986 | 1956 | 1956-01-24 | Point Richmond, Station D | Non-native | 37.9058 | -122.3850 |
819057 | Ruiz GM and JB Geller (2015) | 2012 | San Leandro | None | 37.6580 | -122.2217 | |
819058 | Ruiz GM and JB Geller (2015) | 2012 | Redwood City | None | 37.5574 | -122.1755 | |
819059 | Ruiz GM and JB Geller (2015) | 2012 | Coyote Point | None | 37.5987 | -122.3252 | |
819060 | Ruiz GM and JB Geller (2015) | 2012 | None | None | |||
819061 | Ruiz GM and JB Geller (2015) | 2012 | Corte Madera | None | 37.9309 | -122.4819 | |
819062 | Ruiz GM and JB Geller (2015) | 2012 | Oyster Point | None | 37.6805 | -122.3731 | |
819063 | Ruiz GM and JB Geller (2015) | 2012 | Richardson Bay | None | 37.8788 | -122.4759 | |
819064 | Ruiz GM and JB Geller (2015) | 2012 | Emeryville | None | 37.8596 | -122.3152 | |
819065 | Ruiz GM and JB Geller (2015) | 2012 | Ballena Isle | None | 37.7643 | -122.2978 |
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