Invasion History
First Non-native North American Tidal Record: 1973First Non-native West Coast Tidal Record: 1973
First Non-native East/Gulf Coast Tidal Record:
General Invasion History:
Corophium alienense was described from specimens collected in 1973 from San Francisco Bay, California (CA). Based on its recent discovery and its close affinity to many corophiids known from the Northwestern Pacific (Japan, China, Vietnam), it is considered a probable introduction to the Northeastern Pacific. So far, it is known only from San Francisco Bay, Tomales Bay, and Bodega Harbor, CA (Chapman 1988; Cohen and Carlton 1995; Bousfield and Hoover 1997; Fairey et al. 2002).
North American Invasion History:
Invasion History on the West Coast:
Corophium alienense was described from specimens collected in 1973 in Corte Madera Creek, San Quentin, on central San Francisco Bay. The recent discovery of the species, its morphological affinities to Asian corophiids, and its abundance marked it as a probable introduction to San Francisco Bay (Chapman 1988). Within the estuary, it is known from the Central Bay, the South Bay, San Pablo Bay, Carquinez Strait, Grizzly Bay, and Suisun Bay. Peterson and Vayssieres (2010) found that it was abundant in dry years in Grizzly Bay in 1977-1986, but remained abundant and dominant in both dry and wet years in 1987-2003, after the invasion of the Asian Brackish-water Clam Corbula amurensis. Corophium alienense was found to be abundant in Tomales Bay in 1993 (Cohen and Carlton 1995) and was subsequently collected in Tomales Bay in 2011 (California Department of Fish and Wildlife 2014). Chapman (2007) mentions its presence in Los Angeles Harbor, but we have not found any specific records for Southern California. Although C. alienensis probably originated from the coast of Southeast Asia, it has not been reported outside of California (Chapman 1988; Bousfield and Hoover 1997; Chapman 2007).
Description
The estuarine amphipod Corophium alienense is an infaunal amphipod which burrows in muddy sediments. It has a slender, very depressed body, and a massive Antenna 2, which is longer than Antenna 1. The coxal plates are small and separated. The urosome segments are not fused. Both sexes have a pointed rostrum, extending beyond the eye-lobes. The eye is well-developed, but partially obscured by a pigmented cuticle. The first 3 segments of Antenna 1 have long, plumose setae. The 1st segment of the male Antenna 1 lacks a tooth (present in C. heteroceratum). In females, the ventral setae on segments 1-3 are missing. The flagellum has 13-15 segments. Antenna 2 is proportionately larger in males than females, extending well beyond antenna 1. In both sexes, segment 2 bears a large tooth-like excretory spout. In males, segments 4 and 5 of Antenna 2 bear a row of small teeth on the ventral sides. Segment 4 also has a pointed tooth at its distal end. In females, Antenna 2 is only slightly longer than Antenna 1, and lacks the ventral tooth row on segments 4-5, but has a huge distal tooth on segment 4.
The gnathopods are not especially prominent in this genus. Pereiopod 2 is longer than Pereiopod 21 and its dactyl lacks teeth. Pereiopod 7 is nearly twice as long as Pereiopod 6, and has a long curved, smooth, dactyl. The segments of the urosome are separate. Uropod 1 is the longest and 3 is the smallest. The male type specimen was 5.2 mm and the female allotype was 6.4 mm. The centers of the pleonites are mottled brown and white, but the borders, and the appendages are white (photo, in Barnett et al. 2011). Description based on: Chapman 1988, Chapman 2007, and Barnett et al. 2011.
Although C. alienense is known only from San Francisco Bay, Tomales Bay, and Bodega Harbor (Cohen and Carlton 1995; California Department of Fish and Wildlife 2014), it bears a close morphological similarity to Asian species (Chapman 1988; Bousfield and Hoover 1997). Bousfield and Hoover (1997) placed it in the genus Sinocorophium, together with eight Asian species. John Chapman considers the genus Sinocorophium (Bousfield and Hoover 1997) indistinct from Corophium, and thus invalid (Chapman 2007; John Chapman, personal communication).
Taxonomy
Taxonomic Tree
Kingdom: | Animalia | |
Phylum: | Arthropoda | |
Subphylum: | Crustacea | |
Class: | Malacostraca | |
Subclass: | Eumalacostraca | |
Superorder: | Peracarida | |
Order: | Amphipoda | |
Suborder: | Gammaridea | |
Family: | Corophiidae | |
Genus: | Corophium | |
Species: | alienense |
Synonyms
Sinocorophium alienense (Bousfield and Hoover, 1997)
Corophium dentalium (Ren, 1995)
Potentially Misidentified Species
Corophium heteroceratum was described from China and has been introduced to San Francisco Bay, Los Angeles-Long Beach Harbor, and Tomales Bay (Cohen and Carlton 1995; Fairey et al. 2002; Chapman 2007).
Ecology
General:
Corophium alienense is a tube-building gammarid amphipod, so far only known from California estuaries (Chapman 1988; Cohen and Carlton 1995; Graening et al. 2012). Gammarid amphipods have separate sexes, brooded embryos, and direct development (Bousfield 1973). We have no specific information on the life history of C. alienense. Nocturnal migration is common in the genus (Chapman 1988).
Corophium alienense is tolerant of a wide range of temperature and salinity, and has been collected in marsh pools at a temperature of 30C (Chapman 2007). It ranges into low-salinity waters in Suisun Bay and the Napa River (Cohen and Carlton 1995; Lee et al. 2003; Peterson and Vaysierres 2010). Corophium alienense builds U-shaped tubes in shallow subtidal and intertidal muddy sand (Chapman 1988; Graening et al. 2012). This amphipod is an abundant member of the epifauna on Eelgrass (Zostera marina) in San Francisco Bay (Carr et al. 2011). Corophium alienense is a suspension-feeder, and surface-deposit-feeder. It is considered a significant grazer in brackish tributaries of San Francisco Bay (Jones et al. 2009; Barnett et al. 2011). Fishes are the primary predators of benthic amphipods in these estuaries (Feyrer et al. 2003).
Food:
Detritus; Phytyoplankton
Trophic Status:
Deposit Suspension Feeder
DepSusFedHabitats
General Habitat | Unstructured Bottom | None |
General Habitat | Grass Bed | None |
Salinity Range | Limnetic | 0-0.5 PSU |
Salinity Range | Oligohaline | 0.5-5 PSU |
Salinity Range | Mesohaline | 5-18 PSU |
Salinity Range | Polyhaline | 18-30 PSU |
Tidal Range | Subtidal | None |
Vertical Habitat | Epibenthic | None |
Vertical Habitat | Endobenthic | None |
Life History
Tolerances and Life History Parameters
Minimum Temperature (ºC) | 30 | Field (Chapman 2007) |
Minimum Salinity (‰) | 0.7 | Field, mean salinity, Fresh-Brackish-Muddy zone, San Francisco Delta (Lee et al. 2003) |
Maximum Salinity (‰) | 27.5 | Field, mean salinity, Marine-Muddy zone, South and Central San Francisco Bay (Lee et al. 2003) |
Maximum Length (mm) | 6.4 | Adult female (Chapman 1988) |
Broad Temperature Range | None | Warm temperate |
Broad Salinity Range | None | Tidal Limnetic-Polyhaline |
General Impacts
Corophium alienense is one of the dominant benthic organisms in brackish tributaries of San Francisco Bay. It increased in abundance after the invasion of the Asian Brackish-water Clam (Corbula amurensis) (Peterson and Vayssieres 2010). In Suisun Slough, the estimated grazing rate of C. alienense was ~15X greater than that of C. amurensis. However, the rate of phytoplankton loss due to grazing was much smaller than the loss by sedimentation, which was attributed to a flocculent surface layer of mucus, to which the tubes of C. alienense contributed, along with many other benthic organisms (Jones et al. 2009). Tube-building amphipods, including C. alienense, are important food items for native and introduced benthic-feeding fishes in San Francisco Bay (Feyrer et al. 2003).
Regional Impacts
NEP-V | Northern California to Mid Channel Islands | Ecological Impact | Habitat Change | ||
In Suisun Slough, mucus from the tubes of C. alienense as well as the mucus produced by other native and introduced deposit feeding and tube-building benthos, contributes to a surface layer of flocculent fluff, which may trap much more phytoplankton than that actually consumed by the animals (Jones et al. 2009). | |||||
P090 | San Francisco Bay | Ecological Impact | Habitat Change | ||
In Suisun Slough, mucus from the tubes of C. alienense as well as the mucus produced by other native and introduced deposit feeding and tube-building benthos, contributes to a surface layer of flocculent fluff, which may trap much more phytoplankton than that actually consumed by the animals (Jones et al. 2009). | |||||
P090 | San Francisco Bay | Ecological Impact | Herbivory | ||
Corophium alienense is a significant suspension-feeder in the benthos of Suisun Slough, and other brackish San Francisco Bay tributaries. Specific grazing rates for the population were estimated from those of the similar Atlantic amphipod C. volutator, as 9 m-3 . m-2 . day-1, for the populaiton about 15X higher than that of the Asian Brackish-Water Clam ( Corbula amurensis) population (Jones et al. 2009). This estimate makes it the major suspension-feeder in this part of the San Francisco estuary. | |||||
NEP-V | Northern California to Mid Channel Islands | Ecological Impact | Herbivory | ||
Corophium alienense is a significant suspension-feeder in the benthos of Suisun Slough, and other brackish San Francisco Bay tributaries. Specific grazing rates for the population were estimated from those of the similar Atlantic amphipod C. volutator, as 9 m-3 . m-2 . day-1, for the populaiton about 15X higher than that of the Asian Brackish-Water Clam (Corbula amurensis) population (Jones et al. 2009). This estimate makes it the major suspension-feeder in this part of the San Francisco estuary. | |||||
P090 | San Francisco Bay | Ecological Impact | Food/Prey | ||
Tube-dwelling and free-living gammarid amphipods were important food items for several native (Tule Perch- Hysterocarpus traskii, Prickly Sculpin- Cottus asper, Starry Flounder- Platichthys stellatus) and introduced fishes (Acanthogobius longimanus, Yellowfin Goby) (Feyrer et al. 2003). | |||||
NEP-V | Northern California to Mid Channel Islands | Ecological Impact | Food/Prey | ||
Tube-dwelling and free-living gammarid amphipods were important food items for several native (Tule Perch- Hysterocarpus traskii, Prickly Sculpin- Cottus asper, Starry Flounder- Platichthys stellatus) and introduced fishes (Acanthogobius longimanus, Yellowfin Goby) (Feyrer et al. 2003). | |||||
CA | California | Ecological Impact | Food/Prey | ||
Tube-dwelling and free-living gammarid amphipods were important food items for several native (Tule Perch- Hysterocarpus traskii, Prickly Sculpin- Cottus asper, Starry Flounder- Platichthys stellatus) and introduced fishes (Acanthogobius longimanus, Yellowfin Goby) (Feyrer et al. 2003)., Tube-dwelling and free-living gammarid amphipods were important food items for several native (Tule Perch- Hysterocarpus traskii, Prickly Sculpin- Cottus asper, Starry Flounder- Platichthys stellatus) and introduced fishes (Acanthogobius longimanus, Yellowfin Goby) (Feyrer et al. 2003). | |||||
CA | California | Ecological Impact | Habitat Change | ||
In Suisun Slough, mucus from the tubes of C. alienense as well as the mucus produced by other native and introduced deposit feeding and tube-building benthos, contributes to a surface layer of flocculent fluff, which may trap much more phytoplankton than that actually consumed by the animals (Jones et al. 2009)., In Suisun Slough, mucus from the tubes of C. alienense as well as the mucus produced by other native and introduced deposit feeding and tube-building benthos, contributes to a surface layer of flocculent fluff, which may trap much more phytoplankton than that actually consumed by the animals (Jones et al. 2009). | |||||
CA | California | Ecological Impact | Herbivory | ||
Corophium alienense is a significant suspension-feeder in the benthos of Suisun Slough, and other brackish San Francisco Bay tributaries. Specific grazing rates for the population were estimated from those of the similar Atlantic amphipod C. volutator, as 9 m-3 . m-2 . day-1, for the populaiton about 15X higher than that of the Asian Brackish-Water Clam (Corbula amurensis) population (Jones et al. 2009). This estimate makes it the major suspension-feeder in this part of the San Francisco estuary., Corophium alienense is a significant suspension-feeder in the benthos of Suisun Slough, and other brackish San Francisco Bay tributaries. Specific grazing rates for the population were estimated from those of the similar Atlantic amphipod C. volutator, as 9 m-3 . m-2 . day-1, for the populaiton about 15X higher than that of the Asian Brackish-Water Clam ( Corbula amurensis) population (Jones et al. 2009). This estimate makes it the major suspension-feeder in this part of the San Francisco estuary. |
Regional Distribution Map
Bioregion | Region Name | Year | Invasion Status | Population Status |
---|---|---|---|---|
P110 | Tomales Bay | 2011 | Non-native | Established |
NEP-VI | Pt. Conception to Southern Baja California | 2007 | Non-native | Established |
P050 | San Pedro Bay | 2007 | Non-native | Established |
P112 | _CDA_P112 (Bodega Bay) | 1992 | Non-native | Established |
NEP-V | Northern California to Mid Channel Islands | 1973 | Non-native | Established |
P090 | San Francisco Bay | 1973 | Non-native | Established |
P093 | _CDA_P093 (San Pablo Bay) | 1973 | Non-native | Established |
Occurrence Map
OCC_ID | Author | Year | Date | Locality | Status | Latitude | Longitude |
---|---|---|---|---|---|---|---|
755433 | Introduced Species Study | 2005 | 2005-10-07 | Martinez Marina | Non-native | 38.0276 | -122.1371 |
755434 | Introduced Species Study | 2005 | 2005-10-19 | Rodeo Marina | Non-native | 38.0394 | -122.2717 |
755435 | Introduced Species Study | 2010 | 2010-05-31 | Dumbarton Bridge | Non-native | 37.5070 | -122.1168 |
755436 | Introduced Species Study | 2010 | 2010-05-31 | Redwood Creek - Marina | Non-native | 37.5021 | -122.2130 |
755437 | Introduced Species Study | 2010 | 2010-05-31 | Redwood Creek - Shipping | Non-native | 37.5120 | -122.2109 |
755438 | Introduced Species Study | 2010 | 2010-06-01 | Coyote Point Marina | Non-native | 37.5905 | -122.3177 |
755439 | Introduced Species Study | 2010 | 2010-06-01 | Sea Plane Harbor | Non-native | 37.6349 | -122.3848 |
755440 | Introduced Species Study | 2010 | 2010-06-02 | Ballena Bay | Non-native | 37.7661 | -122.2834 |
755441 | Introduced Species Study | 2010 | 2010-06-02 | Coast Guard Island | Non-native | 37.7812 | -122.2457 |
755442 | Introduced Species Study | 2010 | 2010-06-02 | Port of Oakland Office | Non-native | 37.7954 | -122.2804 |
755443 | Introduced Species Study | 2010 | 2010-06-13 | Hayward Landing | Non-native | 37.6447 | -122.1543 |
755444 | Introduced Species Study | 2010 | 2010-06-28 | Chevron Pier | Non-native | 37.9228 | -122.4105 |
755445 | Introduced Species Study | 2010 | 2010-06-28 | Point Richmond Piers | Non-native | 37.9085 | -122.3913 |
755446 | Introduced Species Study | 2010 | 2010-06-29 | New York Point Marina | Non-native | 38.0400 | -121.8863 |
755447 | Introduced Species Study | 2010 | 2010-07-01 | Ayala Cove | Non-native | 37.8680 | -122.4350 |
755448 | Introduced Species Study | 2010 | 2010-07-12 | Ferry Terminal Pier | Non-native | 37.7945 | -122.3917 |
755449 | Introduced Species Study | 2010 | 2010-07-15 | San Pablo Bay Pumphouse | Non-native | 38.0446 | -122.4326 |
755450 | Introduced Species Study | 2010 | 2010-07-29 | Mare Island Strait - Navy | Non-native | 38.1015 | -122.2695 |
755451 | Introduced Species Study | 2011 | 2011-06-06 | Tomales Bay Boat Launch | Non-native | 38.1991 | -122.9220 |
758364 | J. Chapman, pers. comm., in Carlton 1979 | 1970 | San Francisco Bay | Non-native | 37.8494 | -122.3681 | |
758365 | Chapman 1988 | 1973 | Corte Madera, SE of San Quentin Prison | Non-native | 37.9367 | -122.4871 | |
758366 | Chapman 1988 | 1973 | Mare Island Channel | Non-native | 38.0954 | -122.2612 | |
758367 | Chapman 1988 | 1976 | 1976-08-27 | Coyote Creek, immediately south of the Southern Pacific Railroad Bridge | Non-native | 37.4606 | -121.9748 |
758368 | Chapman 1988 | 1973 | Carquinez Strait, near Benicia Municipal Pier | Non-native | 38.0409 | -122.1739 | |
758369 | Thompson and Nichols 1984; Chapman 1988 | 1974 | 1974-12-10 | Sand Point, Palo Alto (USGS Station 45) | Non-native | 37.4630 | -122.1011 |
758370 | W.C. Fields, pers. comm., in Chapman 1988 | 1980 | Delta General Location | Non-native | 38.0500 | -121.8100 | |
758371 | Chapman 1988 | 1980 | Grizzly Island | Non-native | 38.1485 | -121.9819 | |
758372 | J. Chapman, pers. comm., in Cohen and Carlton 1995 | 1992 | Bodega Harbor | Non-native | 38.3262 | -123.0495 | |
758373 | Cohen and Carlton 1995 | 1993 | Tiburon, San Francisco Bay | Non-native | 37.8881 | -122.4803 | |
758374 | Cohen and Carlton 1995 | 1993 | Napa River, San Pablo Bay | Non-native | 38.1402 | -122.2764 | |
758375 | Cohen and Carlton 1995 | 1993 | Rodeo, San Pablo Bay | Non-native | 38.0394 | -122.2749 | |
758376 | Cohen and Carlton 1995 | 1994 | Tiburon, San Francisco Bay | Non-native | 37.8881 | -122.4803 | |
758377 | Cohen and Carlton 1995 | 1994 | Napa River, San Pablo Bay | Non-native | 38.1402 | -122.2764 | |
758378 | Cohen and Carlton 1995 | 1994 | Rodeo, San Pablo Bay | Non-native | 38.0394 | -122.2749 | |
758379 | Cohen et al. 2005 (SF Bay Area RAS) | 2004 | 2004-05-28 | Rodeo Marina, San Pablo Bay | Non-native | 38.0391 | -122.2711 |
820043 | Ruiz GM and JB Geller (2018) | 2015 | Oakland | None | 37.7056 | -122.2473 | |
820044 | Ruiz GM and JB Geller (2018) | 2015 | Ballena Isle | None | 37.7588 | -122.2834 | |
820045 | Ruiz GM and JB Geller (2018) | 2015 | SF marina | None | 37.8074 | -122.4345 | |
820046 | Ruiz GM and JB Geller (2018) | 2015 | Richardson bay | None | 37.8705 | -122.4797 | |
820047 | Ruiz GM and JB Geller (2018) | 2015 | Smithsonian | None | 37.8981 | -122.4623 | |
820048 | Ruiz GM and JB Geller (2018) | 2015 | Hunters Point | None | 37.7088 | -122.3691 | |
820049 | Ruiz GM and JB Geller (2018) | 2015 | Oyster Point | None | 37.6747 | -122.3753 | |
820050 | Ruiz GM and JB Geller (2018) | 2015 | Union City | None | 37.5865 | -122.1743 | |
820051 | Ruiz GM and JB Geller (2018) | 2015 | Albany | None | 37.8879 | -122.3245 | |
820052 | Ruiz GM and JB Geller (2018) | 2015 | San Lorenzo | None | 37.6480 | -122.2159 | |
820253 | Ruiz GM and JB Geller (2018) | 2016 | SF marina | None | 37.8071 | -122.4345 | |
820254 | Ruiz GM and JB Geller (2018) | 2016 | Bay Farm | None | 37.7237 | -122.2632 | |
820255 | Ruiz GM and JB Geller (2018) | 2016 | Brisbane | None | 37.6560 | -122.3697 | |
820256 | Ruiz GM and JB Geller (2018) | 2016 | Mission Bay | None | 37.7553 | -122.3790 | |
820257 | Ruiz GM and JB Geller (2018) | 2016 | Albany | None | 37.8773 | -122.3241 | |
820258 | Ruiz GM and JB Geller (2018) | 2016 | El Cerrito | None | 37.8885 | -122.3367 | |
820259 | Ruiz GM and JB Geller (2018) | 2016 | Richardson bay | None | 37.8669 | -122.4751 | |
820260 | Ruiz GM and JB Geller (2018) | 2016 | Paradise Cay | None | 37.9044 | -122.4684 | |
820261 | Ruiz GM and JB Geller (2018) | 2016 | Oyster Point | None | 37.6688 | -122.3741 | |
820262 | Ruiz GM and JB Geller (2018) | 2016 | Ballena Isle | None | 37.7516 | -122.2878 |
References
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