Invasion HistoryFirst Non-native North American Tidal Record: 1978
First Non-native West Coast Tidal Record: 1978
First Non-native East/Gulf Coast Tidal Record:
General Invasion History:
Sinocalanus doerri is native to fresh waters of China. The type locality is a pond near Shanghai. This copepod occurs in the Yangtze, Yellow (Huang), and Pearl (Chu) River basins, up to 1000 km from the sea (Orsi et al. 1983).
North American Invasion History:
Invasion History on the West Coast:
On May 31, 1978, Sinocalanus doerri was collected in the Sacramento River, near Pittsburg, California (Orsi et al. 1983). By November 1978, it was found from Collinsville through Suisun Bay, and in the San Joaquin River, near the junction with the Sacramento River at salinities of 0.5 to 10 PSU. In subsequent years, it ranged into eastern San Pablo Bay, and upstream to Mossdale on the San Joaquin River and Hood on the Sacramento River (Orsi et al. 1983). It was later (2000-2001) collected in the Sacramento Turning Basin (Fairey et al. 2002). Abundance and range in the San Francisco estuary varies with rainfall and salinity (Orsi et al. 1983; Ambler 1985). In high rainfall years, its range extends through San Pablo Bay, reaching the central Bay (Bollens et al. 2011). It has been collected at 14.6 PSU, but is much more abundant at 0.5-6 PSU (Orsi et al. 1983). From peak abundances in the early 80s, this copepod has declined into the 90s, with some recovery in the late 90s to 2005 (Baxter et al 2008).
Further north, S. doerri was collected in the Columbia River, Oregon in 1999 and was common by 2002. In a 2002 survey, it was found from the Youngs River, near Astoria, to Sauvie Island, near Portland, at 0-4 PSU (Systma et al. 2004). However, it was not found in continous sampling from 2005 to 2013, at Vancouver, Washington, suggesting that it has failed to colonize the upper tidal freshwater Columbia River (Dexter et al. 2015). In 1990, S. doerrii was found in the Chehalis River estuary, near Grays Harbor, Washington, where it is established, but not abundant (USGS Nonindigenous Aquatic Species Program 2007; Cordell et al. 2007). Sinocalanus doerri was the one of the most abundant animals found in low-salinity ballast water in the tanks of ships arriving in Vancouver, British Columbia (Levings et al. 2004). It was also found in the ballast water of ships entering Puget Sound, from other West coast ports, but not in trans-Pacific vessels (Cordell et al. 2008; Lawrence et al. 2010).
Sinocalanus doerrii has an elongate oval body, with the corners of the last (5th) thoracic segment rounded, but with a short, sharp spine. The antennule (1st antenna) is equal in size to its body length. The caudal rami are about equal to 3 urosome segments in length (Orsi et al. 1983).
Adult females have 3 urosome segments, with a large, swollen genital (1st) segment. The antennules are symmetrical. The exopod of the antenna (2nd antenna) is longer than the endopod. The distal endopod segment is wider than it is long and the exopod of the 2nd segment has a single lobe. The 5th swimming legs (pereiopod, P5) are symmetrical. The 2nd exopod segment has a long inner spine, but lacks an outer spine. The 1st endopod segment lacks inner setae (Orsi et al. 1983).
Adult males have 5 urosome segments. The right antennule is modified, with segments 13-16 enlarged and hinged at segment 19. The 5th swimming legs are asymmetrical (P5). The 1st basipodite segment of the right leg lacks a medial process. The 2nd basipodite has a thumblike medial process (Orsi et al. 1983). Orsi et al. (1983) do not give a size range for this species. An adult male in a photograph is 2.7 mm (Cordell, in Carlton 2007). The copepodite and naupliar stages of this copepod have not been described. This copepod is characteristic of fresh and low-salinity brackish waters (Orsi et al. 1983).
Sinocalanus mystrophorus (Burckhardt, 1913)
Potentially Misidentified Species
Occurs in glacial lakes of northern North America, Eurasia, and the Baltic
Native to freshwaters and estuaries of China
Native to freshwaters and estuaries of China, introduced to Japan
Planktonic calanoid copepods mate in the water column. Males use their modified antenules and 5th pair of swimming legs to grasp the female and transfer spermatophores to the female's genital segment. Female Sinocalanus doerrii lay eggs singly in the water column (Barnes 1983; Orsi et al. 1983). Eggs hatch into nauplii which go through six stages. The first stage, NI, has 3 pairs of appendages and is unsegmented - each molt has additional appendages and/or more differentiation of segments. The sixth stage (NVI) molts into a first copepodite stage (CI), with the basic form of the adult and fully differentiated feeding structures, but with only two pairs of swimming legs and only one urosomal segment. The copepod goes through five additional molts, with increasing numbers of swimming legs, urosomal segments, and sexual differentiation. The sixth (CVI) stage is the male or female adult (Barnes 1983).
Sinocalanus doerrii, like other copepods of its genus, is characteristic of estuaries with low-salinity waters (Orsi et al. 1983). It is capable of completing its life cycle in freshwater, and inhabits tidal fresh waters in the Sacramento-San Joaquin Delta, the Columbia and Chehalis Rivers (Orsi et al. 1983; Cordell et al. 2008b). Copepods of the genus Sinocalanus are suspension-feeders on phytoplankton but also actively capture copepod nauplii, including those of their own species (Hada and Uye 1991).
Phytoplankton, protozoa, copepod nauplii, detritus
|General Habitat||Tidal Fresh Marsh||None|
|General Habitat||Unstructured Bottom||None|
|Salinity Range||Limnetic||0-0.5 PSU|
|Salinity Range||Oligohaline||0.5-5 PSU|
|Salinity Range||Mesohaline||5-18 PSU|
Tolerances and Life History Parameters
|Minimum Temperature (ºC)||2||Field, Columbia River estuary (Bollens et al. 2012)|
|Minimum Salinity (‰)||0||None|
|Maximum Salinity (‰)||14.6||"but ~6.2 is a more common limit" (Orsi et al. 1983).|
|Minimum Duration||5||Egg to adult, 28 C (Kimoto et al. 1986, for S. tenellus)|
|Maximum Duration||85||Egg to adult, 6 C (Kimoto et al. 1986, for S. tenellus)|
|Minimum Length (mm)||2.7||Orsi et al. (1983) do not give sizes for S. doerii. An adult male in a photograph is ~2.7 mm (Cordell, in Carlton 2007).|
|Broad Temperature Range||None||Warm temperate|
|Broad Salinity Range||None||Nontidal Limnetic-Mesohaline|
General ImpactsEcological Impacts
Competition: The role of competition in the invasion and temporary dominance of the copepod community by Sinocalanus doerrii in the late 70's and early 1980s, has been disputed. Differences in the feeding spectrum and salinity range of S. doerrii and the previous dominant, Eurytemora carolleeae, may have reduced competition (Orsi et al. 1983; Meng and Orssi 1991).
Food/Prey: Sinocalanus doerrii was selected against by larval Striped Bass (Morone saxatilis), apparently because of superior escape abilities (Meng and Orsi 1991). From 1980 to 1988, however, S. doerrii was a major component of the diet (30-80%) of juvenile Striped Bass in the San Francisco estuary. After the invasion of Pseudodiaptomus spp., the latter species became the predominant copepod eaten by young striped bass (Meng and Orsi 1991).
|P090||San Francisco Bay||Ecological Impact||Food/Prey|
|Sinocalanus doerrii was selected against by larval Striped Bass (Morone saxatilis), apparently because of superior escape abilities (Meng and Orsi 1991). From 1980 to 1988, however, S. doerrii was a major component of the diet (30-80%) of juvenile Striped Bass. After the invasion of Pseudodiaptomus spp., the latter species became the predominant copepod eaten by young striped bass. Sinocalanus doerri was also selected against by the endangered Delta Smelt (Hypomesus transpacificus (Slater and Baxter 2014).|
|P260||Columbia River||Ecological Impact||Competition|
|Sinocalanus doerrii has a substantial period of temporal overlap and potential competition with the native Northeast Pacific form of 'Eurytemora affinis' in the Columbia estuary (Bollens et al. 2012).|
|26925||Orsi 1983||1979||1979-04-04||Delta - Port of Stockton||Def||37.9522||-121.3277|
|27703||Orsie et al. 1983||1978||1978-05-13||Suisun Bay||Def||38.0713||-122.0581|
|33386||Cohen and Carlton, 1995||1980||1980-01-01||San Pablo Bay||Def||38.0600||-122.3900|
ReferencesAmbler, Julie W.; Cloern, James E.; Hutchinson, Anne (1985) Seasonal cycles of zooplankton from San Francisco Bay., Hydrobiologia 129: 177-197
Baxter, Randall, and 11 Authors (2008) <missing title>, Inter-Agency Ecological Program, Sacramento. Pp. 1-52
Bollens, Stephen M.; Breckenridge, Joanne K.; Cordell, Jeffery R. Simenstad, Charles A.; Kalata, Olga (2014) Zooplankton of tidal marsh channels in relation to environmental variables in the upper San Francisco Estuary, Aquatic Biology 21: 205-219
Bollens, Stephen M.; Breckenridge, Joanne K. Vanden Hoof, Rian C.; Cordell, Jeffery R. (2011) Mesozooplankton of the lower San Francisco Estuary: spatio-temporal patterns, ENSO effects and the prevalence of non-indigenous species, Journal of Plankton Research 33(9): 1358-1377
Bollens, Stephen M.; Breckenridge, Joanne K.; Cordell, Jeffery R.; Rollwagen-Bollens; Gretchen; Kalata, Olga (2012) Invasive copepods in the Lower Columbia River Estuary: Seasonal abundance, co-occurrence and potential competition with native copepods, Aquatic Invasions 7(1): 101-109
Cohen, Andrew N.; Carlton, James T. (1995) Nonindigenous aquatic species in a United States estuary: a case study of the biological invasions of the San Francisco Bay and Delta., U.S. Fish and Wildlife Service and National Sea Grant College Program (Connecticut Sea Grant), Washington DC, Silver Spring MD.. Pp. <missing location>
Cordell, Jeffery R.; Rasmussen, Mikelle; Bollens, Stephen M. (2007) Biology of the introduced copepod Pseudodiaptomus inopinus in a northeast Pacific estuary., Marine Ecology Progress Series 333: 213-227
Cordell, Jeffrey R. and 5 authors (2009) Factors influencing densities of non-indigenous species in the ballast water of ships arriving at ports in Puget Sound, Washington, United States, Aquatic Conservation: Marine and Freshwater Ecosystems 19(3): 322-343
Cordell, Jeffrey; Bollens, Stephen M.; Draheim, Robyn; Sytsma, Mark (2008) Asian copepods on the move: Recent invasions in the Columbia-Snake River system, USA, ICES Journal of Marine Science 65: 753-758
Dexter, Eric; Bollens, Stephen M.; Rollwagen-Bollens, Gretchen; Emerson, Josh; Zimmerman, Julie (2015) Persistent vs. ephemeral invasions: 8.5 years of zooplankton community dynamics in the Columbia River, Limnology and Oceanography 60: 527-539
Fairey, Russell; Dunn, Roslyn; Sigala, Marco; Oliver, John (2002) <missing title>, California Department of Fish and Game, Sacramento. Pp. <missing location>
Hada, Akio; Uye, Shin-ichi (1991) Cannibalistic feeding behavior of the brackish-water copepod Sinocalanus tenellus, Journal of Plankton Research 13(1): 155-166
Kimmerer, William J.; Burau, J. R.; Bennett, W. A. (1998) Tidally oriented vertical migration and position maintenance of zooplankton in a temperate estuary., Limnology and Oceanography 43(7): 1697-1709
Lawrence, David J.; Cordell, Jeffery R. (2010) Relative contributions of domestic and foreign sourced ballast water to propagule pressure in Puget Sound, Washington, USA, Biological Conservation 143: 700–709
Levings, C. D.; Cordell, J. R.; Ong, S.; Piercey, G. E. (2004) The origin and identity of invertebrate organisms being transported to Canada's Pacific coast by ballast water., Canadian Journal of Fisheries and Aquatic Science 61: 1-11
Meng, Lesa; Orsi, James J. (1991) Selective predation by larval striped bass on native and introduced copepods., Transactions of the American Fisheries Society 120: 187-192
Nel, Ronel; Coetzee, P. S.; Van Niekerk, G (1998) The evaluation of two treatments to reduce mud worm (Polydora hoplura Claparede) infestation in commercially reared oysters (Crassostrea gigas Thunberg), Aquaculture 146: 31-39
Orsi, James J., Bowman, Thomas E., Marelli, Dan C., Hutchinson, Anne (1983) Recent introduction of the planktonic calanoid copepod Sinocalanus doerrii (Centropagidae) from mainland China to the Sacramento-San Joaquin Estuary of California, Journal of Plankton Research 5(3): 357-375
Sytsma, Mark D.; Cordell, Jeffrey R.; Chapman, John W.; Draheim, Robyn, C. (2004) <missing title>, Center for Lakes and Reservoirs, Portland State University, Portland OR. Pp. <missing location>
2003-2015 Nonindigenous Aquatic Species Database. Gainesville, FL. http://nas.er.usgs.gov
Winder; Monika; Jassby, Alan D.; Mac Nally, Ralph (2011) Synergies between climate anomalies and hydrological modifications facilitate estuarine biotic invasions, Ecology Letters 14: 749-757