Invasion History

First Non-native North American Tidal Record: 1893
First 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 manhatensis (Prine, 1862)
Gemma pupurea (Lea, 1842)

Potentially Misidentified Species

Nutricola sp.
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

SusFed

Habitats

General HabitatUnstructured BottomNone
General HabitatOyster ReefNone
Salinity RangeMesohaline5-18 PSU
Salinity RangePolyhaline18-30 PSU
Salinity RangeEuhaline30-40 PSU
Tidal RangeSubtidalNone
Tidal RangeLow IntertidalNone
Vertical HabitatEndobenthicNone


Tolerances and Life History Parameters

Minimum Temperature (ºC)-2Based on geographical range (Bousfield 1960)
Maximum Temperature (ºC)3724 hr LC 50, experimental, 30 C acclimation (Kennedy and Mihursky 1971)
Minimum Salinity (‰)5Experimental (Chanley and Castagna 1978)
Maximum Salinity (‰)35Field data (Miller 2000)
Minimum Length (mm)1.8Minimum reprducitive size, Green and Hobson 1978
Maximum Length (mm)5Abbott 1974, Gosner 1978
Broad Temperature RangeNoneCold temperate-Subtropical
Broad Salinity RangeNoneMesohaline-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

P090San Francisco BayEcological ImpactCompetition
Competition is suspected with Nutricola tantilla (=Transenella tantilla), rarely found together in the same samples (Carlton 1979).
P110Tomales BayEcological ImpactCompetition
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 ImpactCompetition
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-VNorthern California to Mid Channel IslandsEcological ImpactCompetition
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-VNorthern California to Mid Channel IslandsEcological ImpactFood/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).
CACaliforniaEcological ImpactCompetition
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).
CACaliforniaEcological ImpactFood/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 Def Estab
P130 Humboldt Bay 1992 Def Estab
P112 _CDA_P112 (Bodega Bay) 1974 Def Estab
P110 Tomales Bay 1965 Def Estab
P080 Monterey Bay 1965 Def Estab
P095 _CDA_P095 (Tomales-Drakes Bay) 1918 Def Estab
P093 _CDA_P093 (San Pablo Bay) 1899 Def Estab
P090 San Francisco Bay 1893 Def Estab
NEP-V Northern California to Mid Channel Islands 1893 Def Estab

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) Def 36.8398 -121.7435
697454 Boyd et al. 2002 (Humboldt Bay Report) 2002 Mad River Slough - Samoa Blvd. Bridge Def 40.8652 -124.1505
697501 Boyd et al. 2002 (Humboldt Bay Report) 2002 Klopp Lake Def 40.8553 -124.0919
697548 Introduced Species Study 2003 2003-08-27 Loch Lomond 2 Def 37.9717 -122.4811
698030 Wasson et al. 2001 (Elkhorn Slough Survey) 1998 Elkhorn Slough Station 10 (Hudson's Langind) Def 36.8578 -121.7572
698615 Cohen et al. 2005 (SF Bay Area RAS) 2004 2004-05-27 Coyote Point Marina, San Francisco Bay Def 37.5907 -122.3180
699418 Introduced Species Study 2010 2010-06-13 Coyote Point Def 37.5920 -122.3210
699750 Introduced Species Study 2010 2010-06-14 Aquatic Park Def 37.8080 -122.4216
699846 Introduced Species Study 2005 2005-06-09 Paradise Area Def 37.9062 -122.4768
700126 Wasson et al. 2001 (Elkhorn Slough Survey) 1998 Elkhorn Slough Station 5 (South Marsh Trail) Def 36.8193 -121.7378
700525 Introduced Species Study 2005 2005-06-08 Sea Plane Lagoon Def 37.7761 -122.2998
700916 Nichols & Thompson 1985a, 1985b 1985 South San Francisco Bay Def 37.5457 -122.1645
701260 Stearns 1899 1899 "Alameda flats" (off Oakland) Def 37.7521 -122.2643
701261 Carlton 1979 1893 San Francisco Bay Def 37.8494 -122.3681
701455 Introduced Species Study 2010 2010-06-30 Hercules Wharf Def 38.0231 -122.2928
701460 Introduced Species Study 2005 2005-10-19 Hercules Wharf Def 38.0231 -122.2928
701804 Carlton 1979 1918 Bolinas Lagoon Def 37.9189 -122.6816
702787 Nichols & Thompson 1985a, 1985b 1985 Central San Francisco Bay Def 37.8595 -122.3884
703155 Boyd et al. 2002 (Humboldt Bay Report) 2002 Mad River Slough - Lanphere Christianson Dunes Bridge Def 40.8979 -124.1356
703598 Introduced Species Study 2005 2005-06-10 Toll Plaza Def 37.8266 -122.3166
703775 Introduced Species Study 2005 2005-06-08 Crown Beach Def 37.7603 -122.2737
703804 Introduced Species Study 2005 2005-06-10 Hayward Landing Def 37.6447 -122.1543
703805 Introduced Species Study 2010 2010-06-13 Hayward Landing Def 37.6447 -122.1543
704087 Nichols & Thompson 1985a, 1985b 1985 San Pablo Bay Def 38.0600 -122.3900
714209 Barnhart et al. 1992 1992 Humboldt Bay Def 40.7500 -124.2083
759628 Packard 1918 1913 South San Francisco Bay Def 37.5457 -122.1645
759629 Packard 1918 1913 Central San Francisco Bay Def 37.8595 -122.3884
759630 Packard 1918 1913 Sausalito vicinity Def 37.8595 -122.4771
759631 Light 1969 1967 Bolinas Lagoon Def 37.9189 -122.6816
759632 Shulenberger 1970 1969 1969-07-31 Walker Creek, Tomales Bay Def 38.2111 -122.9317
759633 Wicksten 1978 1973 Coyote Point Def 37.5906 -122.3169
759634 Chapman and Dorman 1975 1971 Bolinas Lagoon Def 37.9189 -122.6816
759635 Chapman and Dorman 1975 1971 1971-02-20 Pinole Point Def 38.0133 -122.3659
759636 Heiman and Micheli 2010; Hobbs et al. 2015 2002 Elkhorn Slough (Upper) Def 36.8547 -121.7600
759637 Recher 1966 1962 near Mouth of San Francisquito Creek Def 37.4658 -122.1156
759638 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 11 (16-18') Def 38.0169 -122.4258
759639 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 11 (16-18') Def 38.0169 -122.4258
759640 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 11 (16-18') Def 38.0169 -122.4258
759641 Painter 1966b; Hopkins 1986 1973 Carquinez Strait, Station 3 (Deep; off Commodore Jones Point) Def 38.0542 -122.1756
759642 Painter 1966b; Hopkins 1986 1973 Carquinez Strait, Station 23 (6-8') Def 38.0547 -122.1744
759643 Painter 1966b; Hopkins 1986 1973 Carquinez Strait, Station 23 (6-8') Def 38.0547 -122.1744
759644 Painter 1966b; Hopkins 1986 1973 Carquinez Strait, Station 23 (6-8') Def 38.0547 -122.1744
759645 Painter 1966b; Hopkins 1986 1973 Carquinez Strait, Station 23 (6-8') Def 38.0547 -122.1744
759646 Painter 1966b; Hopkins 1986 1973 Carquinez Strait, Station 23 (6-8') Def 38.0547 -122.1744
759647 Painter 1966b; Hopkins 1986 1973 Carquinez Strait, Station 23 (6-8') Def 38.0547 -122.1744
759648 Painter 1966b; Hopkins 1986 1973 Suisun Bay, near Point Edith, Station 4 (Deep) Def 38.0567 -122.0744
759649 Painter 1966b; Hopkins 1986 1973 Suisun Bay, near Point Edith, Station 14 (16-18') Def 38.0597 -122.0764
759650 Painter 1966b; Hopkins 1986 1973 Suisun Bay, near Point Edith, Station 24 (6-8') Def 38.0606 -122.0769
759651 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 31 (Intertidal) Def 38.0833 -122.4797
759652 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 31 (Intertidal) Def 38.0833 -122.4797
759653 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 31 (Intertidal) Def 38.0833 -122.4797
759654 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 31 (Intertidal) Def 38.0833 -122.4797
759655 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 31 (Intertidal) Def 38.0833 -122.4797
759656 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 31 (Intertidal) Def 38.0833 -122.4797
759657 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 31 (Intertidal) Def 38.0833 -122.4797
759658 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 31 (Intertidal) Def 38.0833 -122.4797
759659 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 31 (Intertidal) Def 38.0833 -122.4797
759660 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 31 (Intertidal) Def 38.0833 -122.4797
759661 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 31 (Intertidal) Def 38.0833 -122.4797
759662 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 21 (6-8') Def 38.0889 -122.4636
759663 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 21 (6-8') Def 38.0889 -122.4636
759664 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 21 (6-8') Def 38.0889 -122.4636
759665 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 21 (6-8') Def 38.0889 -122.4636
759666 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 21 (6-8') Def 38.0889 -122.4636
759667 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 21 (6-8') Def 38.0889 -122.4636
759668 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 21 (6-8') Def 38.0889 -122.4636
759669 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 21 (6-8') Def 38.0889 -122.4636
759670 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 21 (6-8') Def 38.0889 -122.4636
759671 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 21 (6-8') Def 38.0889 -122.4636
759672 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 21 (6-8') Def 38.0889 -122.4636
759673 Painter 1966b; Hopkins 1986 1973 San Pablo Bay West, Station 21 (6-8') Def 38.0889 -122.4636
759674 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 22 (6-8') Def 38.0900 -122.3569
759675 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 22 (6-8') Def 38.0900 -122.3569
759676 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 22 (6-8') Def 38.0900 -122.3569
759677 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 22 (6-8') Def 38.0900 -122.3569
759678 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 22 (6-8') Def 38.0900 -122.3569
759679 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 22 (6-8') Def 38.0900 -122.3569
759680 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 22 (6-8') Def 38.0900 -122.3569
759681 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 22 (6-8') Def 38.0900 -122.3569
759682 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 32 (Intertidal) Def 38.1261 -122.3544
759683 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 32 (Intertidal) Def 38.1261 -122.3544
759684 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 32 (Intertidal) Def 38.1261 -122.3544
759685 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 32 (Intertidal) Def 38.1261 -122.3544
759686 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 32 (Intertidal) Def 38.1261 -122.3544
759687 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 32 (Intertidal) Def 38.1261 -122.3544
759688 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 32 (Intertidal) Def 38.1261 -122.3544
759689 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 32 (Intertidal) Def 38.1261 -122.3544
759690 Painter 1966b; Hopkins 1986 1973 San Pablo Bay East, Station 32 (Intertidal) Def 38.1261 -122.3544
759691 Jones 1961; Hopkins 1986 1955 1955-01-15 Point Richmond, Station A Def 37.9211 -122.3881
759692 Jones 1961; Hopkins 1986 1955 1955-03-06 Point Richmond, Station A Def 37.9211 -122.3881
759693 Jones 1961; Hopkins 1986 1955 1955-04-16 Point Richmond, Station A Def 37.9211 -122.3881
759694 Jones 1961; Hopkins 1986 1955 1955-07-09 Point Richmond, Station A Def 37.9211 -122.3881
759695 Jones 1961; Hopkins 1986 1956 1956-01-24 Point Richmond, Station A Def 37.9211 -122.3881
759696 Jones 1961; Hopkins 1986 1956 1956-03-17 Point Richmond, Station A Def 37.9211 -122.3881
759697 Jones 1961; Hopkins 1986 1955 1955-01-15 Point Richmond, Station B Def 37.9114 -122.3889
759698 Jones 1961; Hopkins 1986 1955 1955-03-16 Point Richmond, Station B Def 37.9114 -122.3889
759699 Jones 1961; Hopkins 1986 1955 1955-10-22 Point Richmond, Station B Def 37.9114 -122.3889
759700 Jones 1961; Hopkins 1986 1955 1955-01-29 Point Richmond, Station C Def 37.9036 -122.3853
759701 Jones 1961; Hopkins 1986 1955 1955-03-06 Point Richmond, Station C Def 37.9036 -122.3853
759702 Jones 1961; Hopkins 1986 1955 1955-04-16 Point Richmond, Station C Def 37.9036 -122.3853
759703 Jones 1961; Hopkins 1986 1955 1955-05-28 Point Richmond, Station C Def 37.9036 -122.3853
759704 Jones 1961; Hopkins 1986 1955 1955-07-09 Point Richmond, Station C Def 37.9036 -122.3853
759705 Jones 1961; Hopkins 1986 1955 1955-09-15 Point Richmond, Station C Def 37.9036 -122.3853
759706 Jones 1961; Hopkins 1986 1955 1955-10-22 Point Richmond, Station C Def 37.9036 -122.3853
759707 Jones 1961; Hopkins 1986 1955 1955-11-26 Point Richmond, Station C Def 37.9036 -122.3853
759708 Jones 1961; Hopkins 1986 1956 1956-01-24 Point Richmond, Station C Def 37.9036 -122.3853
759709 Jones 1961; Hopkins 1986 1956 1956-03-17 Point Richmond, Station C Def 37.9036 -122.3853
759710 Jones 1961; Hopkins 1986 1955 1955-01-29 Point Richmond, Station D Def 37.9058 -122.3850
759711 Jones 1961; Hopkins 1986 1955 1955-03-06 Point Richmond, Station D Def 37.9058 -122.3850
759712 Jones 1961; Hopkins 1986 1955 1955-04-16 Point Richmond, Station D Def 37.9058 -122.3850
759713 Jones 1961; Hopkins 1986 1955 1955-05-28 Point Richmond, Station D Def 37.9058 -122.3850
759714 Jones 1961; Hopkins 1986 1955 1955-07-09 Point Richmond, Station D Def 37.9058 -122.3850
759715 Jones 1961; Hopkins 1986 1955 1955-09-15 Point Richmond, Station D Def 37.9058 -122.3850
759716 Jones 1961; Hopkins 1986 1955 1955-10-22 Point Richmond, Station D Def 37.9058 -122.3850
759717 Jones 1961; Hopkins 1986 1955 1955-11-26 Point Richmond, Station D Def 37.9058 -122.3850
759718 Jones 1961; Hopkins 1986 1956 1956-01-24 Point Richmond, Station D Def 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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