Invasive and Non-native Aquatic Invertebrates in the Lower Coos Watershed Summary: § Over 60 non-native aquatic invertebrate species have been identified in the project area, but for most, little information is available about their population status, distribution, or local impacts. § Future invasions of non-native invertebrate species are likely to occur, facilitated by international and domestic shipping, new aquaculture ventures, and climate change. § Significant damage has been documented in the project area caused by invasive invertebrate species (e.g. burrowing and parasitic isopods). Subsystems: CR- Coos River; CS- Catching Slough; HI- Haynes Inlet; IS- Isthmus Slough; LB- Lower Bay; NS- North Slough; PS- Pony Slough; SS- South Slough; UB- Upper Bay Figure 1: Invasive and non-native invertebrate study areas. Invasive and Non-native Species in the Lower Coos Watershed 18-79 What’s Happening Terms Used in This Chapter This data summary provides information about the 62 known non-native aquatic inver- Species Origin tebrate species that have become established Native: naturally occurs in an area without human facilitation; evolutionarily connect- in the lower Coos watershed (project area), as ed to an area well as nine high risk aquatic non-native spe- cies that are not currently in the project area Non-native: plants or animals introduced either intentionally or accidentally to loca- but predicted to arrive here in the future. tions outside their native ranges Invasive: non-native species that aggres- This summary is divided into five sections: sively outcompete native species, causing significant economic loss and/or environ- 1) Established Non-Native Species With mental harm. Not all non-native species Known Impacts – status of non-native are invasive. species established in the project area Population Status that have documented local impacts or Established: self-maintaining populations known impacts in nearby invaded areas. Not established: reported in an area, but does not have a self-maintaining popula- 2) Established Non-Native Species With tion Unknown Impacts – status of non-native Unknown: insufficient spatial or temporal species established in the project area for information available to classify status which no impacts have been studied or documented. Predicted: established in nearby locations and likely to be introduced to Coos estuary 3) Predicted Threats – status of non-native species that are likely to arrive in the proj- ect area based on geographic proximity, available vectors, and invasion trends of the species. 4) Threats to Human Health – describes the human health threats posed by several Tables summarizing the species discussed species. begin each section (Tables 1, 3 and 4). In each section (and table) the species are organized 5) Background on Species with Known alphabetically by scientific name within the Impacts – describes ecological/economic general groupings of: biofoulers (sponges, impacts that have been documented for hydroids, anemones, bryozoans, barnacles the 29 Established Non-Native Species and sea squirts), molluscs (snails, clams, mus- With Known Impacts. In cases where no sels, and oysters), crustaceans (crabs, shrimp, information exists for local impacts, infor- isopods, and amphipods), and worms. mation from nearby areas is included. 18-80 Invasive and Non-native Species in the Lower Coos Watershed The individual summaries describe what’s Section 1. Established Non-Native Species known about species’ introductions to the with Known Impacts (Table 1) project area and current distribution (where available). Information included in this Biofoulers (sponges, hydroids, anemones, summary is based on two comprehensive tube-building amphipods, bryozoans, and published lists (Ruiz et al. 2000, Wonham and sea squirts) Carlton 2005), as well as data collected from more recent surveys. However, very little in- Blackfordia virginica formation exists about any particular species’ Hydroid (no common name) spatial distribution and presence from year to year. Species are included in Predicted Threats This hydroid is native to the Black and Caspian (Section 3) if they’re established in nearby es- Seas, but has successfully invaded European tuaries and have a high likelihood of becom- waters, the western Atlantic Ocean, India and ing introduced to the project area (see “Major China. It was first collected in the 1970s on Vectors of Invasion” sidebar on page 18-87). the Pacific Coast in the San Francisco estuary, (originally misidentified/correctly identified in Each species listed in Section 1 (species estab- early 1990s)(Cohen and Carlton 1995). It was lished in the project area with known im- later collected in the Coos estuary in 1997 pacts) is symbolized within a yellow icon and and reported to be abundant by July 1999 symbol based on the type of threat they pose. (Carlton 2000). It was likely introduced on Threats to native species and habitats are ship hulls as a fouling organism and through denoted with a fish icon. Economic threats ballast water (Cohen and Carlton 1995). (e.g. to industry, infrastructure, fisheries, etc.) are denoted with a dollar sign. Species that Botrylloides violaceus are predicted threats (Section 3) are similarly Orange sheath sea squirt symbolized, within a red icon (see example below). This sea squirt is considered native to Japan, although difficulty in species identification (and uncertainty of species status) has com- plicated the delineation of accurate native and introduced ranges for species in the Symbol showing high environ- Symbol showing high environ- mental and economic threat for mental and economic threat genus. However, it’s fairly well agreed that it an establisehd species that has for a species that is a predicted known impacts (yellow). threat (red). was not found north of Southern California Invasive and Non-native Species in the Lower Coos Watershed 18-81 Table 1 (continued on next page): Non-native aquatic invertebrates established in the project area that have documented threats to habitat/native species (salmon icon at column head) and/or the local economy (dollar sign icon). Detection date indicates the first known date of project area invasion. Project area subsystem codes (see also Figure 1): CR- Coos River; CS- Catching Slough; HI- Haynes Inlet; IS- Isthmus Slough; LB- Lower Bay; NS- North Slough; PS- Pony Slough; SS- South Slough; UB- Upper Bay * SH = Southern Hemisphere; WP = West Pacific (e.g., China, Japan); UNK = unknown; PC = Ponto-Caspian; NA = North Atlantic; EA = East Atlantic (e.g., Europe north of Spain); WA = West Atlantic. ** BW = ballast water; SF = ship fouling; CO = commercial oyster culture; IP = intentional plantings; UNK = unknown. 18-82 Table 1 (continued): Non-native aquatic invertebrates established in the project area that have documented threats to habitat/native species (salmon icon at column head) and/or the local economy (dollar sign icon). Detection date indicates the first known date of project area invasion. Project area subsystem codes (see also Figure 1): CR- Coos River; CS- Catching Slough; HI- Haynes Inlet; IS- Isthmus Slough; LB- Lower Bay; NS- North Slough; PS- Pony Slough; SS- South Slough; UB- Upper Bay * SH = Southern Hemisphere; WP = West Pacific (e.g., China, Japan); UNK = unknown; PC = Ponto-Caspian; NA = North Atlantic; EA = East Atlantic (e.g., Europe north of Spain); WA = West Atlantic. ** BW = ballast water; SF = ship fouling; CO = commercial oyster culture; IP = intentional plantings; UNK = unknown. 18-83 until the 1940s and 1950s (Cohen and Carlton encrusting communities consisted of colonies 1995). In a 1988-1990 survey, Hewitt (1993) of this sea squirt. Hewitt (1993) reports the found B. violaceus in South Slough, as well as coverage of B. violaceus in Isthmus Slough at sites in the middle and upper Coos estuary declined in subsequent years to 5-10%, but it (Figure 2)(Table 2). During this two year study had also spread seaward from the upper bay recruitment of B. violaceus peaked from June at a rate of 2 km/yr from 1991-1993 to Pony to September, but extended into November Slough in the middle bay (Figure 2). A decade during one year. Hewitt (1993) also tracked later, surveys of non-native fouling communi- the transport of B. violaceus on a floating ties showed B. violaceus was present in 2003 dock from Joe Ney Slough (part of South at the Charleston Boat Basin Marina, Empire Slough) to Isthmus Slough in June of 1990. By Pier, and near Valino Island in South Slough September 1990, the total percent coverage (Figure 3)(de Rivera et al. 2005). It was also of B. violaceus on the transplanted dock had found the following year at the Port of Coos grown to 60%. Recruitment of B. violaceus to Bay Citrus Dock in the upper Coos estuary (de areas adjacent to the dock was also observed Rivera et al. 2005). and by September 1990, 20% of the adjacent Figure 2: Locations of Hewitt’s (1993) study sites (points on map) where he investigated populations of invasive/ non-native encrusting organisms. Distinct regions were delineated based on Hewitt’s study, and based on similarities of sample sites. Region delineation should not be confused with similarly named project area regions commonly used in this and other chapters.The red squares with callouts on map and adjoining table show the secondary dispersal (within the Coos estuary) of the colonial sea squirt Botrylloides violaceus. *Although originally found in South Slough (site 1 on map), it was manually moved to Isthmus Slough (site 2) and dispersal distances were calculated from that point. Data Source: Hewitt 1993. 18-84 Invasive and Non-native Species in the Lower Coos Watershed Table 2: Invasive aquatic invertebrates recruited into the lower Coos and Isthmus Slough between 1988-1990. Data: Source Hewitt 1993 Botryllus schlosseri most likely spread throughout its introduced Golden star sea squirt range by ship hull fouling and with oyster shipments from the Atlantic and Asia (Hewitt 1993). As with B. violaceus, the native range and Bugula neritina introduction history of this sea squirt are Spiral-tufted bushy bryozoan ambiguous, but it is presumed to be a native of European waters.