Cothurnia limnoriae - NSCEP | US EPA - US Environmental ...

accumulate in rocky intertidal tide pools live in unconsolidated sediment in a consolidated
ecosystem.
Third, most of the natural history attributes are classified as either “Observed” or “Preferred”.
We make this distinction because may marine/estuarine species can be found across a wide range
of environmental conditions, yet the majority of the population occurs in a much more restricted
range. An example is the occasional offshore records of estuarine species. While we do not have
hard and fast rules, Observed is used to capture the full range of conditions over which a species
has been reported, even if the conditions are marginal. Preferred is used to indicate the
conditions that the species normally occupies. Indicators of Preferred habitats include: 1) species
occurring frequently within the habitat range; 2) species occurring at high densities within the
habitat range; 3) presence of breeding populations within the habitat range, and 4) experts
identifying the habitat as preferred.
Lastly, we note temperature is not included in the species profiles. We excluded temperature
because the temperature classes in the PICES database were derived from Hall’s (1964)
biogeographic analysis of mollusks, which we do not consider adequate. To the extent that they
are known, the quantitative temperature ranges for adults and reproduction are given in the
PICES database.
RESULTS AND ANALYSIS
Taxonomic Patterns of Invasion
The patterns of invasion by taxonomic group are displayed in Figure 25 and Figures 27 to 58,
with taxa that contain four or more NIS in any one biogeographic unit plotted individually. Four
phyla constituted more than 70% of the 747 NIS (Figure 25) - Arthropoda (224), Chordata (114),
Mollusca (110), and Annelida (89). Within the arthropods, the invaders were divided among five
classes - Malacostraca (127), Insecta (45), Maxillopoda (36), Pycnogonida (12) and Ostracoda
(4). Amphipods were the most numerous nonindigenous group within the Malacostraca, with a
total of 50 NIS, while the isopods were the second most numerous, with a total of 34 NIS. The
patterns of these two peracaridan groups differed geographically. Substantially more
nonindigenous amphipods occurred in the NEP (37) than Hawaii (20) or the NWP (7) (Figure
47). In comparison, the NEP and Hawaii had approximately equal numbers of nonindigenous
isopods, 20 and 21 respectively (Figure 48). The only other malacostracan taxon with more than
10 NIS was the decapods, which had a total of 29 NIS. Substantially more nonindigenous
decapods occurred in the NWP (16) than Hawaii or the NEP (Figure 50). However, nine of the
16 nonindigenous decapods in the NWP are aquaculture species or were intentionally released
into the environment, and removing these species from the counts resulted in similar numbers of
decapod invaders across the three biogeographic units.
The copepods were the most numerous taxon within the Maxillopoda, with 22 nonindigenous
species (Figure 51). Copepods were predominantly found in the NEP (18 NIS). Copepod
invaders within the NEP consisted of 12 pelagic Cyclopoida and Calanoida, four benthic
Harpacticoida, and two parasitic Poecilostomatoida. Barnacles constituted the other taxon within
the Maxillopoda, with a total of 14 nonindigenous species. The NWP contained more than twice
the number of nonindigenous barnacles compared to Hawaii or the NEP (Figure 52).
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