Description
Synonymy- Synonymy- Most authorities synonymize Cordylophora caspia, named by Pallas in 1771, from the Caspian Sea with C. lacustris, named by Allman (1844) from Ireland. The name 'C. lacustris' is still widely used, although there is no evidence that 'C. lacustris' exists as a separate species from 'C. caspia'. The use of the name 'lacustris' is based on the idea that Pallas's description of 'C. caspia' was inadequate (Hutchinson 1993).
Genetic studies (Folino-Rorem et al. 2009) indicate that multiple (at least 4) genetic lineages of Cordylophora spp., possibly representing cryptic species, have been introduced in Europe, North Ameirca and South America. Most of these lineages have been widely distributed, and multiple lineages can occur at the same site. One lineage (2b) was confined to the Pacific Coast of North America, although it co-occured with a more-widely distributed lineage (1B). Lineages differed ecologically- 1A was found only in freshwater, 2A and 2B only in brackish waters, while 1B was found at both fresh and brackish sites. This study was wide-ranging, but did not include the Ponto-Caspian basin, the presumed region of origin of the Cordylophora species complex. Only one collection came from the Chesapeake Bay region, the James River, VA, and belonged to the freshwater clade, 1A (Folino-Rorem et al. 2009).
Taxonomy
| Kingdom | Phylum | Class | Order | Family | Genus |
|---|---|---|---|---|---|
| Animalia | Cnidaria | Hydrozoa | Anthomedusae | Clavidae | Cordylophora |
Synonyms
Invasion History
Chesapeake Bay Status
| First Record | Population | Range | Introduction | Residency | Source Region | Native Region | Vectors |
|---|---|---|---|---|---|---|---|
| 1877 | Established | Stable | Introduced | Regular Resident | Eastern Atlantic | Eastern Atlantic | Shipping(Fouling Community) |
History of Spread
Cordylophora caspia (Freshwater Hydroid) was first described from the Caspian Sea by Pallas in 1771 and is believed to have been native to the Black Sea-Caspian Sea region (Briggs 1931; Naumov 1969; Hutchinson 1993). It appears to have spread rapidly through inland canals and by coastal shipping to inland waters and estuaries of Europe, reaching Ireland by 1842 (Allman 1844). ['It is highly probable that Cordylolophora lacustris (= C. caspia) is an introduced species, possibly imported into this country (Great Britain), as Dreissena polymorpha has been supposed to be, on foreign timber, and like this mollusc, is now making its way into our canals and rivers' (Allman 1872).] First records in other coastal regions are much later, e.g. 1871 for the Darsst-Zwingel estuary, Germany (Arndt 1984), 1884 for the Eems estuary, Belgium (Vervoort 1964), suggesting a rather spotty pattern of spread.
Shipping has spread Cordylophora caspia through much of the world, it reached Australia by 1885 (Briggs 1931), and the Panama Canal by 1944 (Fraser 1944). This hydroid is now known from temperate and tropical coastal regions of every continent (except Antarctica), and from many fresh waters as well (Arndt 1984; Folino-Rorem et al. 2009; Hutchinson 1993; Naumov 1969; Slobodkin and Bossert 1991).
The first published record of Cordylophora caspia in North America was that of Leidy (1870), in which he described its occurrence in the Schuykill River PA, but remarked on finding it at Newport RI 'some years earlier'. Subsequently, this species was found in estuaries and coastal fresh waters up and down the Atlantic coast, and inland as well. In 1909, it was collected in the Mississippi Basin (Havana IL, Illinois River) (Smith 1910), and spread in a scattered fashion to KY (1922, Garman, cited by Hubschman and Kishler 1972), LA (1918, Poirier and Denoux 1973), OK (~1968, Ransom 1981), KS (1980, Ransom 1981). In other Gulf of Mexico drainages, it was first collected in FL (Escambia River) in 1952-53 (Wurtz and Roback 1955), and in TX (Sabine River) in 1976 (McClung et al. 1978). In the Great Lakes, C. caspia was first collected in Lake Erie in 1956, and was abundant by the 1960's (Davis 1957; Hubschman 1971; Hubschman and Kishler 1972). Sometime between the 1930's and the 1950's, C. caspia appeared on Pacific coast estuaries in CA and WA, including San Francisco Bay, the Columbia River, and Puget Sound (Carlton 1979; Cohen and Carlton 1995; Hand and Gwillam 1951).
Atlantic Coast records are summarized below from north to south:
Gulf of Maine - Cordylophora caspia was reported from St. Andrews, New Brunswick, and the Gaspe peninsula, Quebec before 1912 and from the Miramichi estuary, New Brunswick (Fraser 1944).
Massachusetts Bay - Cordylophora caspia was collected in the Charles River, Cambridge MA, 1932, '4.4 miles above the dam', but associated with some brackish water fauna (Blake 1932).
Cape Cod and Vicinity - Cordylophora caspia was listed by Verrill and Smith (1873) for brackish ponds on Martha's Vineyard. Nobska Pond, Woods Hole (1899), and other brackish ponds near Falmouth and on Martha's Vineyard MA (Hargitt 1908; Sumner et al. 1913).
Rhode Island Sound - Cordylophora caspia was found at Newport RI, probably in a coastal pond, 'some years' before 1870 (Leidy 1870).
Long Island Sound- Cordylophora caspia was collected in Essex CT in the Connecticut River estuary in 1995 (Smith et al. 2002); and was also found in fresh upper reaches of the river from Hinsdale NH to Hadley MA (Smith et al. 2002);
Hudson River - Cordylophora caspia was probably established in late 1800's, but we have no early records. The first published report was in 1972 (Mills et al. 1997).
Delaware River Estuary - Cordylophora caspia was found in the Schuylkill River, Fairmount PA, 1870. 'This is the first time that he had noticed this interesting compound hydroid polyp in the vicinity of Philadelphia, and he was surprised that until now it had escaped his notice' (Leidy 1870). It was also abundant in Fairmount Reservoir, Philadelphia PA, 1884 (Potts 1884).
Chesapeake Bay - Cordylophora caspia was first found by Clarke in 1877 (Clarke 1878), but it may have occured 30-40 years earlier, based on observations of Uhler, cited by Bibbins (1893). Chesapeake records are summarized below.
Pamlico River NC - Cordylophora caspia was abundant in oligo-mesohaline stations in the river, upstream of Pamlico Sound, 1972-73 (Dean and Bellis 1975).
Coastal SC - Cordylophora caspia was abundant in fresh-mesohaline zones of the Upper Ashepoo, North Santee Rivers (Calder 1976; Calder and Hester 1978).
Gulf of Mexico - In the Escambia River FL, 1952-53, C. caspia was 'an abundant population occurring on saw grass stalks and roots' (Wurtz and Roback 1955). It was found at 23 locations in the New Orleans area and Vermillion Parish LA, including tidal fresh and brackish waters (Poirrier and Denoux 1973).
Chesapeake Bay records:
James River - Cordylophora caspia was not found at City Point in 1892, but considered likely to occur downriver (Bibbins 1893). In the late 1960s, Calder collected it at Deep Water Shoal, Lawnes Point, Hog Island Point, and Jamestown Island, in oligo-mesohaline regions of the river (Calder 1971).
York River - Cordylophora caspia was found in the York at West Point in 1893 (Bibbins 1893), and in the Mattaponi River near Indian Reservation (Calder 1971).
Rappahannock River - Cordylophora caspia was collected at Tappahannock (mesohaline) (Calder 1971).
Potomac River - Cordylophora caspia was found at Mathias Point (Woodstock) VA, and upriver to Fort Washington MD (Bibbins 1893). In a microscope-slide fouling study of the tidal fresh Potomac (Chain Bridge-Piscataway Creek), Spoon only collected it at the lowermost station (Piscatway Creek) (Spoon 1976). However, some colonies of C. caspia were found in 1988-1991 in the Chesapeake and Ohio canal, near Lock 5, Georgetown, adjacent to the tidal river (Banta and Backus 1991). The downstream limit was given as Douglas Point MD, ~20 km downstream of Piscataway Creek, in the lower oligohaline zone (Lippson et al. 1979).
Patuxent River - In a fouling survey of the lower estuary, C. caspia was abundant only at the uppermost station, Upper Marlboro (fresh-low mesohaline), but occurred downstream to Patuxent Bridge (middle mesohaline). However, it was not found more than 1-2 miles upriver of Lower Marlboro, in the upper mesohaline zone(Cory 1967).
Upper Bay - Cordylophora caspia was first collected (1877) in Curtis Creek, just south of Baltimore, 'in great abundance' (Clarke 1878). 'This, however, was not the first observation of this hydroid in these waters, since Professor Uhler informs me that when a boy he used to fish in Furnace Branch [tributary of Curtis Creek], near the 'old furnace', and had repeatedly noticed these moss-like creatures attached to the submerged fragments of slag from the furnace' (Bibbins 1893). Bibbins found it in upper Bay tributaries from the Patapsco to the Severn in 1890-93 (Bibbins 1893). In our fouling studies (1994-1997), C. caspia was abundant from our uppermost stations, in the Middle River subestuary (oligohaline) to Key Bridge (Pataspsco River, Baltimore Harbor), and at Love Point (Kent Island) on the Eastern Shore (Ruiz et al. unpublished data). This hydroid occurred at least as far downbay as the Rhode River-West River system (Ruiz et al. unpublished data), but was absent in a ten-year fouling study at Calvert Cliffs (Abbe 1987). Our data suggest interannual shifts in abundance and occurrence with riverflow and salinity, as well as strong seasonality (Ruiz et al. unpublished data).
In the spring of 1995, a few hydroids from the Lower Bay (Gloucester Point VA, Virginia Eastern Shore) were tentatively identified as this species (Ruiz et al., unpublished data). However, these specimens were not examined by expert taxonomists.
History References - Abbe 1987; Allman 1844; Allman 1872; Arndt 1984; Banta and Backus 1991; Bibbins 1893; Blake 1932; Briggs 1931; Calder 1971; Calder 1976; Calder and Hester 1978; Carlton 1979; Clark 1878; Cohen and Carlton 1995; Cory 1967; Davis 1957; Dean and Bellis 1975; Diaz 1977; Fraser 1944; Hand and Gwillam 1951; Hargitt 1908; Hubschman 1971; Hubschman and Kishler 1972; Hutchinson 1993; Leidy 1870; Lippson et al. 1979; McClung et al. 1978; Mills et al. 1997; Naumov 1969; Pfitzenmeyer 1976; Poirrier and Denoux 1973; Potts 1884; Ransom 1981; Ruiz et al. unpublished data; Slobodkin and Bossert 1991; Smith 1910; Spoon 1976; Sumner et al. 1913; Vervoort 1964; Verrill and Smith 1873; Wurtz and Roback 1955
Invasion Comments
Range Status- The known range of Cordylophora caspia (Calder 1971; Cory 1967; Lippson et al. 1979; Ruiz et al. unpublished data) is similar to that known or suspected by Bibbins (1893) in most respects, given the limited nature of his searches.
Ecology
Environmental Tolerances
| For Survival | For Reproduction | |||
|---|---|---|---|---|
| Minimum | Maximum | Minimum | Maximum | |
| Temperature (ºC) | 0.0 | 30.0 | 16.0 | 30.0 |
| Salinity (‰) | 0.0 | 35.0 | 0.0 | 27.0 |
| Oxygen | hypoxic | |||
| pH | 6.2000000000 | 8.6000000000 | ||
| Salinity Range | fresh-meso |
Age and Growth
| Male | Female | |
|---|---|---|
| Minimum Adult Size (mm) | 5.0 | 5.0 |
| Typical Adult Size (mm) | 100.0 | 100.0 |
| Maximum Adult Size (mm) | 400.0 | 400.0 |
| Maximum Longevity (yrs) | ||
| Typical Longevity (yrs |
Reproduction
| Start | Peak | End | |
|---|---|---|---|
| Reproductive Season | |||
| Typical Number of Young Per Reproductive Event |
|||
| Sexuality Mode(s) | |||
| Mode(s) of Asexual Reproduction |
|||
| Fertilization Type(s) | |||
| More than One Reproduction Event per Year |
|||
| Reproductive Startegy | |||
| Egg/Seed Form |
Impacts
Economic Impacts in Chesapeake Bay
Cordylophora caspia (Freshwater Hydroid) is a widespread fouling organism in low-salinity waters in Chesapeake Bay. However, it appears to constitute only a minor problem for power plants in the region, in contrast to Garveia franciscana. The Potomac River Power plants, in Alexandria VA (Potomac Electric Power Company), where C. caspia does occur, had only minimal biofouling (Krueger 1997 personal communication).
References- Krueger 1997
Economic Impacts Outside of Chesapeake Bay
Cordylophora caspia (Freshwater Hydroid) is noted as a common fouling organism in many parts of the world. It has been reported from the cooling water systems of power plants in Finland (Vuorinen et al. 1984), Luxembourg (Massard and Geimer 1990), and Ukraine (Simkina 1963). However, it does not seem to have posed serious problem problems for industrial water use. Ecological impacts on fisheries also have not been documented.
References- Massard and Geimer 1990; Simchina 1964; Vuorinen et al. 1984
Ecological Impacts on Chesapeake Native Species
Cordylophora caspia (Freshwater Hydroid) is now a significant biomass component of the fouling community in fresh-mesohaline regions of Chesapeake Bay, and many estuaries around the world. It is also the only erect compound hydroid occuring in inland freshwater lakes (Hutchinson 1967; Pennak 1978). However, information on the ecological impact of its invasion is scarce, and mostly anecdotal, although some experimental studies have been conducted in Chesapeake Bay (Von Holle and Ruiz 1997; Von Holle unpublished data).
Competition- Cordylophora caspia is a potential competitor for space in fouling communities. In field experiments on fouling plates (Key Bridge, Patapsco River MD), where laboratory-grown colonies of C. caspia were added, abundances of Victorella pavida (cryptogenic), Metafolliculina sp., and Stentor sp. on the surrounding regions of the plate were reduced (Von Holle and Ruiz 1997; Von Holle unpublished data).
Food/Prey- Cordylophora caspia is a an important food for nudibranchs, which include many specialized predators on hydroids. In site of its nematocysts, C. caspia is also eatern by some generalized predators, such as amphipods. Cordylophora caspia is apparently eaten by the native nudibranch Tenellia fuscata, although confusion of T. fuscata with the cryptogenic nudibranch T. adspersa makes this uncertain (Gaulin et al. 1986; Chester 1997). Extensive feeding by the amphipod Gammarus tigrinus (native in Chesapeake Bay) on C.caspia was reported in Dutch freshwaters by Roos (1979).
Predation - Although colonies of Cordylophora caspia in many bodies of water represent a substantial biomass of predator son zooplankton and mobile epibenthos (Arndt 1984; Bibbins 1893; Roos 1979), their role as predators does not seem to have been studied quantitatively.
Habitat Change - Cordylophora caspia colonies are dense and bushy, and constitute a substantial structural alteration to surfaces of wood, plants, rocks, etc., providing some protection from predators and currents (Roos 1979). In field experiments, addition of laboratory-grown colonies of C. caspia resulted in increased abundances of Balanus improvisus, Nereis succinea, and Corophium spp. on fouling plates (Von Holle and Ruiz 1997; Von Holle unpublished data).
Other - Cordylophora caspia has been recorded as a fouling organism on living freshwater bivalves (Amblema plicata Threeridge; Potamilus purpuratus- Bleufer) in LA (Curry et al. 1981). However, impacts of C. caspia on the clams were not reported.
References - Bibbins 1893; Chester 1997; Curry et al. 1981; Gaulin et al. 1986; Hutchinson 1967; Pennak 1978; Roos 1979; Vogel 1977; Von Holle and Ruiz unpublished data
Ecological Impacts on Other Chesapeake Non-Native Species
Cordylophora caspia (Freshwater Hydroid) is closely associated with many other introduced and cryptogenic species in much of its present range (Carlton 1979; Roos 1979; Vuorinen et al. 1986), including Chesapeake Bay (Ruiz et al. unpublished data).
Competition - Cordylophora caspia is a potential competitor for space with the cryptogenic bryozoan Victorella pavida In field experiments on fouling plates (Key Bridge, Patapsco River MD), addition of laboratory-grown colonies of C. caspia resulted in decreased abundance of Victorella pavida (Von Holle and Ruiz unpublished data).
Food - The nudibranch Tenellia adspersa (cryptogenic in Chesapeake Bay) is potentially an important predator on Cordylophora caspia. [Because of the difficulty of separating it from T. fuscata, its relative abundance and impact in the Chesapeake Bay is uncertain.] With hydroids and nudibranchs from Great Bay NH, exposure to T. adspersa (identified in the paper as T. fuscata; Chester personal communciation 1997) chemical cues and predation caused an alteration of C. caspia's growth form, resulting in a greater density of hydranths. This could limit later settlement of T. adspersa larvae. Tenellia adspersa's predation on C. caspia thus seems to have complex effects, small numbers of Tenellia might actually increase C. caspia biomass (Gaulin et al. 1986).
Habitat Change - In field experiments, addition of laboratory-grown colonies of C. caspia resulted in increased abundances of the introduced entoproct Loxosomatoides laevis, on fouling plates (Von Holle and Ruiz 1997; Von Holle unpublished data).
References - Carlton 1979; Chester 1997; Chester personal communication 1997; Gaulin et al. 1986; Roos 1979; Von Holle and Ruiz unpublished data; Vuorinen et al. 1986
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