TABLE 2B. Definitions of variables in the Nodes data sheet.
| Column Number | Column Header | Variable | Variable Description |
| 1 | System | nominal | The specific system to which the node information applies. In these datasets, system refers to "estuary". |
| 2 | NodeID | nominal numeric | The unordered nominal node specific ID number of the discrete species lifecycle stage.� |
| 3 | SpeciesID | nominal numeric | The unordered Species ID number. This is independent of Node ID number and is consistent across nodes depicting different lifecycle stages of the same species. If one wishes to combine across life stages they can substitute this number for the Node ID in analyses. |
| 4 | StageID | nominal numeric | The ordinal Stage ID number within species. Adult lifecycle stages are designated as 1. The youngest lifecycle stage is then 2, next youngest 3, etc. Each number corresponds to a particular lifecycle stage that is consistent within a group but not between them (Examples: for trematodes 2 = parthenitae, but for dipterans 2 = larvae). Not all of a species' lifecycle stages are necessarily present a particular food web. |
| 5 | Stage | nominal enumerated | Note, "adult" includes juveniles (prereproductives) for species with no metamorphosis separating the two. |
| 6 | SpeciesID.StageID | nominal numeric | The unique nominal numeric code for a node that combines Species ID and Stage ID, which are separated by a decimal point. |
| 7 | WorkingName | nominal | A working name for each node that is intended to be informative and useful. When available, widely used common names were employed. If no common name exists then a species name was used. If no species name was available, then a working or descriptive name was employed. |
| 8 | OrganismalGroup | Acanthocephalan | Includes all Acanthocephala |
| 8 | OrganismalGroup | Amphipod | Includes all Amphipoda |
| 8 | OrganismalGroup | Annelid | Includes all Polychaete and Oligochaete, but not Hirudinea. |
| 8 | OrganismalGroup | Anthozoan | Includes all Anthozoa |
| 8 | OrganismalGroup | Beetle | Includes all Coleoptera |
| 8 | OrganismalGroup | Bird | Includes all Aves |
| 8 | OrganismalGroup | Bivalve | Includes all Bivalvia |
| 8 | OrganismalGroup | Branchiuran | Includes all Branchiura |
| 8 | OrganismalGroup | Burrowing Shrimp | Includes all Thalassinidea and Stomatopoda |
| 8 | OrganismalGroup | Cestode | Includes all tapeworms |
| 8 | OrganismalGroup | Copepod | Includes only free-living copepods |
| 8 | OrganismalGroup | Crab | Includes all Brachyura |
| 8 | OrganismalGroup | Cumacean | Includes all Cumacea |
| 8 | OrganismalGroup | Detritus | Includes all detritus |
| 8 | OrganismalGroup | Dipteran | Includes all Diptera except Culicidae |
| 8 | OrganismalGroup | Elasmobranch | Includes all Elasmobranchii |
| 8 | OrganismalGroup | Fish | Includes all Actinopterygii |
| 8 | OrganismalGroup | Holothurian | Includes all Holuthuria |
| 8 | OrganismalGroup | Isopod | Includes free-living and symbiotic isopods |
| 8 | OrganismalGroup | Leech | Includes all Hirudinea |
| 8 | OrganismalGroup | Leptostracan | Includes all Leptostraca |
| 8 | OrganismalGroup | Mammal | Includes all Mammalia |
| 8 | OrganismalGroup | Monogenean | Includes all Monogenea |
| 8 | OrganismalGroup | Mosquito | Includes all Culicidae |
| 8 | OrganismalGroup | Myxozoan | Includes all Myxozoa |
| 8 | OrganismalGroup | Nematode | Includes all symbiotic Nematoda |
| 8 | OrganismalGroup | Nemertean | Includes all free-living Nemertea |
| 8 | OrganismalGroup | Ophiuroid | Includes all brittlestars |
| 8 | OrganismalGroup | Ostracod | Includes all Ostracoda |
| 8 | OrganismalGroup | Phoronid | Includes all Phoronida |
| 8 | OrganismalGroup | Plant | Includes all photosynthesizers (phytoplankton, microphytobenthos, plants, macroalgae) and parasitic plants. |
| 8 | OrganismalGroup | Protist | Includes all Protists, free-living and symbiotic |
| 8 | OrganismalGroup | Snail | Includes all Gastropoda, including "slugs" |
| 8 | OrganismalGroup | Spider | Includes all Aranae |
| 8 | OrganismalGroup | Tanaidacean | Includes all Tanaidacea |
| 8 | OrganismalGroup | Trematode | Includes all Trematoda (only Digenea encountered in this data set) |
| 8 | OrganismalGroup | Turbellarian | Includes all free-living Turbellaria |
| 8 | OrganismalGroup | Virus | Includes all viruses except phages |
| 8 | OrganismalGroup | Water Boatman | Includes all Corixidae |
| 9 | NodeType | Detritus | The node is a non-living resource stock (Examples: carrion, nitrate) |
| 9 | NodeType | Organism Parts | Node refers to a specific edible portion or part of an organism (Examples: the leaves, fruit or roots of a tree). |
| 9 | NodeType | Taxon | The node is resolved to a recognized taxonomic level (generally species) but has not been broken into discrete lifecycle stages (Examples: birds, fish). |
| 9 | NodeType | Life Stage | A species has been broken into life stages, each of which is a discrete node (Examples: Blue Mussel adult = Node 90, while Blue Mussel larvae = Node 106). |
| 9 | NodeType | Functional Group | The node is resolved to a commonly recognized ecological functional group that does not share a common taxonomic affiliation (Examples: zooplankton, meiofauna, etc.).� |
| 10 | Resolution | nominal | The lowest taxonomic level to which a Node has been identified, or an indication of whether a node represents an aggregated assemblage. A node does not have to be keyed out to a specific epithet to be treated as a discrete species. Higher taxonomic classifications denote aggregation of species in a node. |
| 11 | ResolutionNotes | nominal | Any notes on node resolution (Examples: whether or not a node described as a discrete species is actually suspected of being a cryptic species assemblage). |
| 12 | Feeding | Feeding | The node represents a consumer in the web. |
| 12 | Feeding | Non-Feeding | The respective node does not represent a consumer in the web. This designation applies, for instance, to detritus and non-feeding metazoan life stages (Example: cerariae). |
| 12 | Feeding | Autotroph | The node converts simple inorganic molecules into complex organic molecules through photosynthesis or chemosynthesis. |
| 13 | Lifestyle(stage) | Free-Living | The node does NOT have a symbiotic relationship with another species, but interacts with several heterospecific individuals throughout the duration of its life stage. |
| 13 | Lifestyle(stage) | Infectious | The node has an obligate parasitic symbiosis with another species.� |
| 13 | Lifestyle(stage) | Commensal | The node has a non-trophic symbiosis with another species, usually using the host organism as habitat (Example: trematode metacercariae encysted on a crab carapace). |
| 13 | Lifestyle(stage) | Mutualist | The node has a symbiosis with another organism where, on average the fitness of the individuals involved in the symbiosis is greater, than if each is not in the symbiotic relationship. |
| 14 | Lifestyle(species) | Free-Living | The species does NOT have a symbiotic relationship with another species, but interacts with several heterospecific individuals throughout its life. |
| 14 | Lifestyle(species) | Infectious | The species has an obligate parasitic symbiosis with another species. |
| 14 | Lifestyle(species) | Commensal | The species has a non-trophic symbiosis with another species, usually using the host organism as habitat (Example: trematode metacercariae encysted on a crab exoskeleton). |
| 14 | Lifestyle(species) | Mutualist | The species has a symbiosis with another organism where, on average, fitnesses of the individuals involved are greater than if each were not in the symbiotic relationship. |
| 15 | ConsumerStrategy(stage) | Autotroph | A individual that converts simple inorganic molecules into complex organic molecules through photosynthesis or chemosynthesis. |
| 15 | ConsumerStrategy(stage) | Predator | A consumer individual that, within a single lifecycle stage, kills and consumes more than one individual of its prey (resource) species (Examples: snakes, warblers, clams). By killing a resource individual, the individual predator reduces the resource individual's fitness to zero in an intensity-independent manner�. |
| 15 | ConsumerStrategy(stage) | Social Predator | A consumer individual that cooperates with one or more conspecifics to kill and consume a single individual of the prey species (Example: wolves, army ants).� |
| 15 | ConsumerStrategy(stage) | Micropredator | A consumer individual that, within a single lifecycle stage, feeds on more than one individual host resource but does not kill that resource individual. Damage to the resource is intensity-dependent, the more micropredators feeding on a resource individual the greater the resource's loss of fitness. (Example: mosquitoes, leafhoppers, most butterfly fishes). Micropredators can be important vectors for pathogens. |
| 15 | ConsumerStrategy(stage) | Parasitic Castrator | A consumer individual blocks the reproduction of its individual host. Thus, while they reduce host fitness to zero, parasitic castrators do not kill their host and often do not reduce the ability of the host to survive. The effect on the host is intensity-independent, in that there is no additive reproductive effect of additional parasitic castrators on the host (Example: digenean trematodes in first intermediate molluscan hosts, bopyrid isopods, rhizocephalan barnacles, most Strepsiptera). |
| 15 | ConsumerStrategy(stage) | Pathogen | A consumer individual that infects an individual host and then multiplies within that host. Death of the host will ensue unless the infection is limited by host defensive mechanisms or external forces (Examples: other consumers). The effects are intensity-independent, as the outcome may result from a single infectious agent (or inoculum). These consumers are appropriately modeled using microparasite models (Anderson and May, 1979)(Examples: smallpox, diphtheria, malaria, lice, scale insects, Gyrodactylus spp.). |
| 15 | ConsumerStrategy(stage) | Macroparasite | A consumer individual that infects an individual host, does not cause the death of its host and does not reduce the fitness of its host to zero. Also it cannot be trophically transmissible to other hosts. Impact on the host is intensity-dependent, These consumers are appropriately modeled using macroparasite models (May and Anderson, 1979) (Examples: adult cestodes, Ichthyopthirius ciliates, corn borers, whip worms, fleas and most parasitic copepods). |
| 15 | ConsumerStrategy(stage) | Pollinator | A consumer individual that facilitates the fertilization of a resource individual. The consumer serially interacts with numerous resource individuals and this distinguishes it from symbiotic (durable) mutualisms. (Examples: bees, hummingbirds). |
| 15 | ConsumerStrategy(stage) | Parasitoid | A consumer individual that kills only a single host individual. Its impact on the host is intensity-independent (Examples: parasitoid wasps, bacteriophages, bruchid beetle larvae in seeds, insect iridoviruses, pasteurella viruses, nematomorphs). If the host is an adult, reproduction ceases before host death. |
| 15 | ConsumerStrategy(stage) | Trophically Transmitted Parasitic Castrator | An infectious consumer individual that blocks host reproduction and requires that its host to be consumed by an appropriate predator host in order to complete its lifecycle. Trophically transmitted parasitic castrators often modify host to increase trophic transmission to the predator host (Examples: Schistocephalus tapeworm pleroceroid larvae, some microphallid trematode metacercariae in molluscan hosts). |
| 15 | ConsumerStrategy(stage) | Trophically Transmitted Pathogen | An infectious consumer individual that multiplies within a host and requires that the host be consumed by an appropriate predator host to complete its lifecycle. Trophically transmitted pathogens often modify host behavior to increase trophic transmission to the predator host (Examples: mulitlocular hydatid tapeworm cysts, Toxoplasma merozoites).� |
| 15 | ConsumerStrategy(stage) | Trophically Transmitted Parasite | An infectious consumer that to complete its life cycle requires that its host be consumed by an appropriate predator host. Its effect on the prey host is intensity-dependent. They often modify host behavior to increase trophic transmission to the predator host (Examples: most larval tapeworms, most trematode metacercariae, Guinea worms).� |
| 15 | ConsumerStrategy(stage) | Trophically Transmitted Commensal | The symbiont that does not have a trophic interaction with its host but in order to complete its life cycle, the symbiont requires that a predator or micropredator consume its host. In order for the trophic transmission to be successful, the predator or micropredator that consumes the symbiont's host must in turn be a viable host for the symbiont.� |
| 15 | ConsumerStrategy(stage) | Detritivore | A consumer individual that feeds on or breaks down dead animal and plant matter (Examples: many fungi, dung beetles, vultures). |
| 15 | ConsumerStrategy(stage) | Symbiotic Mutual | A symbiont with a positive interaction with its host (Examples: hermatypic corals and zooxanthellae) |
| 15 | ConsumerStrategy(stage) | Facultative Micropredator | The outcome of a feeding interaction of a facultative micropredator depends on the relative size of the prey or host individual. On a large host the consumer is a micropredator, but on a small prey the consumer is a predator. The relative sizes determining feeding outcomes are system specific (Examples: vampire bats, lampreys, fang blennies). Related terms used in system and taxon-specific contexts include browser, grazer and sublethal predator. |
| 16 | HabitatAffiliation | nominal | An unordered enumerated characterization of the habitat zone or type where the organism is found (Examples: a bivalve may be in the soft-sediment or benthos). |
| 17 | Mobility | Low | These are generally small benthic invertebrates and small demersal fishes that don�t have large ranges within the system, and likely remain in the system. |
| 17 | Mobility | Intermediate | These are vagile individuals that move within the system, but likely remain in the system (Examples: killifish) |
| 17 | Mobility | High | These are vagile individuals that likely move outside of the system, and thus have trophic links occurring outside the systems (Examples: willets) |
| 18 | Residency | Resident | These are species composed of individuals whose geographic distribution does not vary appreciably throughout the year.� |
| 18 | Residency | Migrant | These are species composed of individuals that spend a substantial portion of the year in a geographic region outside of the system (Examples: those that seasonally leave to breed). |
| 19 | NativeStatus | Native | Any organism assumed to have arrived, established and survived in the system without the direct or indirect aid of modern humans.� |
| 19 | NativeStatus | Non-native | An organism that was introduced to the system as an indirect or direct result of modern human activity. |
| 20 | BodySize(g) | continuous numeric | The mean body size (grams wet weight, soft & hard parts) of an individual node. If units vary, a separate BodySizeUnits column can be employed. |
| 21 | BodySizeSD | continuous numeric | The standard deviation for body size. |
| 22 | BodySizeN | integer | The number of individuals that were sampled to estimate average body size. |
| 23 | BodySizeEstimation | Approximation | Here body size was approximated in one of two ways.� Species were either assigned a body size relative to the body size of another species or node. Examples: the hemipteran, Trichocoryxia sp., was given the weight estimated for the similarly sized salt marsh amphipod, Traskorchestia traskiana. Examples: we estimated adult Ephydra flies as being 0.75 the mass of their larvae. Or, species� body mass was approximated in some other way. For example, the approximate size of the larval stage (trophophore/nectochaete) of all polychaete species was given the average mass of a sample of unidentified polychaete larvae from CSM. |
| 23 | BodySizeEstimation | Population | Mean body weight reflects the local population size structure. Weights were obtained from individuals encountered during stratified random sampling in that estuary (Kuris et al. 2008). The estimate was usually based on length measurements, often including width and height. We obtained individual weight by either using weight-length curves (obtained for that species or for related or similarly shaped animals), or by using estimated body volume and assuming tissue density of 1.1 g/mL. Because parasitic castrators grow in close proportion to host growth, we applied parasite to host weight ratios to the population mass-frequency distribution of infected hosts (we directly measured weight ratios for many species and gave average species estimates to other species). |
| 23 | BodySizeEstimation | Species | We obtained the species� mean individual weight from the literature, by directly weighing voucher specimens, or by multiplying an estimate of body volume by a tissue density of 1.1 g/mL as described in Kuris et al. (2008). |
| 24 | BodySizeNotes | nominal | Notes on the calculation the body size for a particular node in a particular system. |
| 25 | Abundance(no./ha) | integer | The average numeric density (number of individuals/hectare) of a particular node in a particular system. If units vary, a separate AbundanceUnits column can be employed. |
| 26 | Abundance95%CL | integer | The 95% confidence limits for the abundance estimate. |
| 27 | AbundanceDF | integer | The degrees of freedom used to calculate the 95% CL for abundance. Note, in these datasets, the stratified sampling design results in fractional degrees of freedom. |
| 28 | Biomass(kg/ha) | continuous numeric | The average biomass density (kilograms/hectare, soft & hard parts) of a particular node in a particular system. Count density can be approximated from biomass and body size. If units vary, a separate BiomassUnits column can be employed. |
| 29 | Biomass95%CL | continuous numeric | The 95% confidence limits for the biomass estimate. Note, in these datasets, the stratified sampling design results in fractional degrees of freedom. |
| 30 | BiomassDF | continuous numeric | The degrees of freedom used to calculate the 95% CL for biomass. |
| 31 | BiomassEstimation | Quantification, estuary-wide sampling | Biomass density derived from quantitative, stratified random sampling in an estuary as described in Kuris et al. (2008). |
| 31 | BiomassEstimation | Quantification, limited sampling | Biomass density extrapolated from quantitative sampling in that estuary that was restricted to particular habitats or sites (Examples: benthic diatom densities from seven CSM flats and channels; phytoplankton densities estimated for the lagoon at EPB). |
| 31 | BiomassEstimation | Extrapolation from other estuary | Biomass density derived from density estimates for that species quantified in another estuary, adjusted for estuary-specific habitat areas.� Example: the planktonic foraminiferan density estimated in CSM channels was extrapolated to EPB and BSQ channels. |
| 31 | BiomassEstimation | Approximation, ratio | Biomass density for a particular species' lifecycle stage is estimated relative to the quantified density of another life-stage in the same estuary. For instance, adult stages of the fly, Ephydra, were estimated as being 1/10 the biomass of their larval biomass. The ratio is estimated as a logical first-order� approximation, and is not based on quantitative data. |
| 31 | BiomassEstimation | Approximation, quantified ratio | Biomass density is estimated relative to quantified density of another node in the same or different estuary, where the ratio relating the nodes was based on quantitative data (Examples: relative species' abundances in plant point-count transects in the same estuary, the ratio between other life stages among estuaries, or the ratio between life stages of a closely related species). |
| 31 | BiomassEstimation | Quantified apportionment | Biomass density is estimated by apportioning quantified total assemblage biomass by the quantified relative species' abundances at other life stages. As an example for infectious species, the biomass of adult trematode species in birds was estimated by applying the quantified relative abundances of larval stages to the estimates of total adult trematode parasite biomass in Kuris et al. 2008. As an example for free-living species, the abundance of the larvae of a species of bivalve was estimated by apportioning the quantified estimates of total bivalve larval abundance by the quantified relative abundance of adults or juveniles of that species. |
| 31 | BiomassEstimation | Extrapolation and quantified apportionment | Biomass density is estimated as for quantified apportionment, but the total assemblage biomass density was extrapolated from another estuary. |
| 31 | BiomassEstimation | Biomass vs. body size relationship | Biomass density is estimated from the quantified average cross-species relationship for the assemblage in that estuary between biomass and body size (Hechinger et al. unpublished). |
| 31 | BiomassEstimation | Field experience | Biomass density is estimated based on field experience in the system. Examples: an estimation of the node's abundance relative to another better quantified node (Examples: carrion), or by estimation of the total population size (Example: raccoons). |
| 32 | BiomassNotes | nominal | Notes concerning biomass of a particular node in a particular system. |
| 33 | Kingdom | nominal | Taxonomic unit |
| 34 | Phylum | nominal | Taxonomic unit |
| 35 | Subphylum | nominal | Taxonomic unit |
| 36 | Superclass | nominal | Taxonomic unit |
| 37 | Class | nominal | Taxonomic unit |
| 38 | Subclass | nominal | Taxonomic unit |
| 39 | Order | nominal | Taxonomic unit |
| 40 | Suborder | nominal | Taxonomic unit |
| 41 | Infraorder | nominal | Taxonomic unit |
| 42 | Superfamily | nominal | Taxonomic unit |
| 43 | Family | nominal | Taxonomic unit |
| 44 | Genus | nominal | Taxonomic unit |
| 45 | SpecificEpithet | nominal | Taxonomic unit |
| 46 | NodeNotes | nominal | Any general notes on the node |