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Taxa Tolerance Values



Soil & Water Conservation Society of Metro Halifax (SWCSMH; limnesImg-atsign-bold.gifchebucto.ns.ca)

Updated: January 03, 2013         Diversity and Biotic Indices         Chemical vs Biological monitoring


Notes: The tolerance values have mostly been adopted from other extensively published research which have proven to be of pragmatic value. We have also been testing those in lakes (and some streams) in Nova Scotia and are finding they are applicable in most instances with some exceptions; even in the latter case, the values did not differ by more than 1-2 points. As we collect more data over the next decade or longer, we will develop revised values, if necessary! At present, a significant number of our data are in field books and lab notes.

Contents


Introduction

Tolerance

(Bode et al., 1996; Plafkin et al., 1989; Mackie, 2000)

Tolerance is a listing of tolerance values for each taxon used in the calculation of numerous well tested indices foremost among which are the Hilsenhoff species-level Biotic Index and the Family Biotic Index. Tolerance values range from 0 for organisms very intolerant of organic wastes to 10 for organisms very tolerant of organic wastes. Most of these values were taken from Hilsenhoff (1987) but were modified using latter data from Bode et al (1996 and 2002). For species not inluded in Hilsenhoff’s listing, such as oligochaeta, values were assigned based on water quality data from the Stream Biomonitoring Unit surveys of New York and from other literature references. Values taken from survey data were assigned by taking the mean of the tolerance values of other species in the sample.

The Hilsenhoff tolerance values were derived from more than 53 Wisconsin streams.



RBP II: Tolerance values (mostly family levels)

Note: While the taxa reported in Table-1 below had been identified in northeastern North America, nevertheless, all of them may not be present in every micro ecosystem! We have been testing the applicability of the scores in the natural lakes within the Halifax Regional Municipality (HRM), and we are finding a surprising confirmation although most of these scores were derived from streams from elsewhere. In rare cases of nonconfirmation and if confirmed by latter studies, we will be modifying same; to date the scores did not deviate by more than one point over a score of ten!



Table-1: Tolerance Values for macroinvertebrates for application in the Modified Family Biotic Index and other metrics (Barbour et al., 1999; Bode et al., 1996, 2002; Hauer & Lamberti, 1996; Hilsenhoff, 1988; Plafkin et al., 1989)--- some common names have been included for informational purposes!
Feeding Habit lists the primary feeding habit for each family (an approximation from the component species), using the following abbreviations:

c-f: collector-filterer
c-g: collector-gatherer
prd: predator
scr: scraper
shr: shredder
par: parasite
omn: omnivore
pir: piercer

TaxonFeeding
Habit
Tolerance
Superphylum Arthropoda, Phylum Entoma
Subphylum Uniramia
Class Collembola (springtails)
Isotomurus sp.c-g5
 
Order Ephemeroptera (mayflies)
Ameletidaec-g0
Baetidaec-g/scr5
Baetiscidaec-g4
Caenidaec-g6
Ephemerellidaec-g/scr1
Ephemeridaec-g3
Heptageniidaescr3
Isonychiidaec-f2
Leptophlebiidaec-g3
Leptohyphidaec-g4
Metretopodidae 2
Oligoneuriidae 2
Polymitarcyidaec-g2
Potomanthidaec-g4
Siphlonuridaec-g4
Tricorythidae 4
 
Order Odonata (dragonflies and damselflies)
Aeshnidaeprd3
Calopterygidaeprd6
Coenagrionidaeprd8
Cordulegastridaeprd3
Corduliidaeprd2
Gomphidaeprd3
Lestidaeprd6
Libellulidaeprd2
Macromiidaeprd2
 
Order Plecoptera (stoneflies)
Capniidaeshr2
Chloroperlidaeprd/c-g0
Leuctridaeshr0
Nemouridaeshr2
Peltoperlidaeshr0
Perlidaeprd2
Perlodidaeprd2
Pteronarcyidaeshr0
Taeniopterygidaeshr2
 
Order Hemiptera (water or true bugs)
Corixidae (water boatmen?)prd5
 
Order Trichoptera (caddisflies)
Apataniidaescr3
Brachycentridaeshr/c-f1
Calamoceratidae 3
Dipseudopsidaec-f5
Glossosomatidaescr1
Goeridaescr3
Helicopsychidaescr3
Hydropsychidaec-f4
Hydroptilidaescr/shr/c-g4
Lepidostomatidaeshr1
Leptoceridaec-g/shr/prd4
Limnephilidaeshr/scr/c-g3
Molannidaescr6
Odontoceridaescr0
Philopotamidaec-f3
Phryganeidaeshr/prd4
Polycentropodidaec-f/prd6
Psychomyiidaec-g/scr2
Rhyacophilidaeprd1
Sericostomatidae 3
Uenoidaescr3
 
Order Lepidoptera (butterflies and moths)
Arctiidaeshr5
Nepticulidaeshr5
Pyralidaeshr/scr5
 
Order Coleoptera (beetles)
Curculionidaeshr5
Dryopidaescr5
Dytiscidaeprd5
Elmidaescr/c-g4
Gyrinidaeprd4
Haliplidaeshr5
Hydrophilidaec-g/prd/shr5
Psephenidaescr4
Ptilodactylidaeshr3
Scirtidaescr5
 
Order Megaloptera (fishflies, dobsonflies, alderflies)
Corydalidae (fishflies, dobsonflies, hellgrammites)prd4
Sialidae (alderflies)prd4
 
Order Neuroptera
Sisyridae (spongillaflies)
Climacia sp.prd5
 
Order Diptera (Two-winged or "true flies")
Anthomyiidae (root maggot flies)prd6
Athericidaeprd4
Blephariceridae (net-winged midges)scr0
Ceratopogonidae (biting midges or no-see-ums)prd6
Chaoboridae (phantom midges)prd8
 
Family Chironomidae (non-biting or true midges)
Family Chironomidae, Blood-red (Chironomini)8
Family Chironomidae, Other (including pink)6
   Subfamily Tanypodinaeprd7
   Subfamily Podonominaec-g1
   Subfamily Diamesinaec-g2
   Subfamily Prodiamesinaec-g7
   Subfamily Orthocladiinaec-g/shr/prd6
   Subfamily Chironominaec-g/prd/shr/
c-f/scr
6
 
Culicidae (mosquitoes)c-f8
Dolichopodidaeprd4
Dixidae (dixid midges)c-f1
Dolochopodidae 4
Empididae (dance flies)prd6
Ephydridae (shore flies, brine flies)shr6
Muscidaeprd6
Psychodidae (moth flies)c-g8
Ptychopteridaec-g9
Scathophagidae (dung flies)shr6
Simuliidae (black flies)c-f6
Stratiomyidae (soldier flies)c-g7
Syrphidae 10
Tabanidae (horse and deer flies)c-g/prd5
Tanyderidaec-g3
Tipulidae (crane flies)c-g/prd/shr3
 
Subphylum Chelicerata
Class Arachnida
Order Acariformes
   Arachnoidea (water mites)
Arrenuridaeprd6
Lebertiidaeprd6
Atractideidaeprd6
Mideopsidaeprd6
Tyrellidaeprd6
Limnesidaeprd6
Limnocharidaeprd6
Sperchonidaeprd6
Unionicolidaeprd6
 
Class Diplopoda
Polydesmida

c-g

6
 
Subphylum Crustacea
Order Isopoda (sow bugs)c-g8
Anthuridaec-g5
Idoteidaec-g5
Asellidaec-g8
 
Order Amphipoda (scuds; side swimmers)c-g4-8
Crangonyctidaec-g6
Gammaridaec-g6
Oedicerotidaec-g5
Talitridae/Hyalellidaec-g8
 
Order Cumaceac-g5
 
Order Decapoda (shrimps, crabs, etc.)c-g6
 
Order Cladocera (water fleas)
   Daphnia
c-f
c-f
8
8
 
Subclass Copepoda
   Cyclopoida
c-f
c-f
8
8
 
Class Ostracoda (seed shrimps)c-g8
 
Phylum Mollusca
Class Gastropoda (snails and limpets)scr7
Basommatophora (pulmonates)
   Physidae
   Lymnaeidae
   Planorbidae
   Ancylidae

c-g
c-g
scr
scr

8
6
7
6
Mesogastropoda (prosobranches)
   Viviparidae
   Pleuroceridae
   Bithyniidae
   Hydrobiidae
   Valvatidae

scr
scr
scr
scr
scr

6
6
8
6
8
 
Class Pelecypoda/Bivalvia (clams and mussels)c-f8
Unionida
   Unionidae (freshwater pearly mussel)

c-f

6
Veneroidea
   Corbiculidae (Asian clams)
   Dreisseniidae (zebra and quagga mussels)
   Sphaeriidae (fingernail or pea clams)
   Pisidiidae

c-f
c-f
c-f
c-g

6
8
6
8
 
Phylum Annelida
Class Oligochaeta (aquatic worms) 8
Haplotaxida
   Haplotaxidae

prd

5
Lumbricidac-g6
Lumbriculida
   Lumbriculidae

c-g

5
Tubificida
   Enchytraeidae
   Tubificidae
   Naididae

c-g
c-g
c-g/prd

10
9
8
 
Class Hirudinea (leeches and bloodsuckers)
Bdellidae 10
Glossiphoniidae
   Helobdella
   Other Glossiphoniidae

par/prd
prd

6
8
 
Class Aphanoneura
Aeolosomatida
   Aeolosomatidae

c-f

8
 
Class Branchiobdellida (leech-like ectosymbionts)
Branchiobdellida
   Branchiobdellidae

c-g

6
 
Class Polychaeta (freshwater tube worms)
Sabellidaec-g6
 
Phylum Platyhelminthes
Class Turbellaria (planarians/dugesia)prd4
Platyhelminthidae 4
 
Phylum Coelenterata
Hydridae
Hydra sp.prd5
 
Phylum Nemertea (ribbon worms)
Tetrastemmatidae
Prostoma graecenseprd8


Modified Family Biotic Index (FBI)

(Plafkin et al., 1989; Mackie, 2000)

............ suitable as an initial assessment for detecting sites of intermediate impairment with relatively little additional time and effort. It can thus be used to prioritize sites for more intensive evaluation (i.e., RBP III, replicate sampling, ambient toxicity testing, etc.)!

Tolerance values (Table-1) range from 0 to 10 for families and increase as water quality decreases. The index was developed by Hilsenhoff (Hilsenhoff, 1988) to summarize the various tolerances of the benthic arthropod community with a single value. The Modified Family Biotic Index (FBI) was developed to detect organic pollution and is based on the original species-level index (BI) of Hilsenhoff. Tolerance values for each family were developed by weighting species according to their relative abundance in the State of Wisconsin.

In unpolluted streams the FBI was higher than the BI, suggesting lower water quality, and in polluted streams it was lower, suggesting higher water quality. These results occurred be­cause the more intolerant genera and species in each family predominate in clean streams, whereas the more tolerant genera and species predominate in polluted streams. Thus the FBI usually indicates greater pollution of clean streams by overestimating BI values and usually indicates less pollution in polluted streams by underestimating BI values. The FBI is intended only for use as a rapid field procedure. It should not be substituted for the BI; it is less accu­rate and can more frequently lead to erroneous conclusions about water quality (Hilsenhoff, 1988).

The family-level index has been modified for the RBP II to include organisms other than just ar­thropods using the genus and species-level biotic index developed by the State of New York (Bode et al., 1991, 1996). Although the FBI may be applicable for toxic pollutants, it has only been evaluated for organic pollutants. The formula for calculating the Family Biotic In­dex is:

FBI = Σ(xi*ti)/(n), where

xi = number of individuals within a taxon
ti = tolerance value of a taxon
n = total number of organisms in the sample (100)


Table-2: Evaluation of water quality using the family-level biotic index (Hilsenhoff, 1988)
Family Biotic IndexWater QualityDegree of Organic Pollution
0.00-3.75ExcellentOrganic pollution unlikely
3.76-4.25Very goodPossible slight organic pollution
4.26-5.00GoodSome organic pollution probable
5.01-5.75FairFairly substantial pollution likely
5.76-6.50Fairly poorSubstantial pollution likely
6.51-7.25PoorVery substantial pollution likely
7.26-10.00Very poorSevere organic pollution likely
Note: Hilsenhoff’s family-level biotic index (1988) may require modification for some regions



RBP III: Tolerance values based on species/generic levels

Note: While the taxa reported in the below referenced Project H-1 had been identified in northeastern North America, nevertheless, all of them may not be present in every micro ecosystem! We generally concentrate on family, and where needed, on genus levels. But we carry out random verification with species levels IDs when necessary. We are finding a surprising confirmation of the scores in the natural lakes within the Halifax Regional Municipality (HRM) although most of these scores were derived from streams from elsewhere. In rare cases of nonconformance, and if confirmed by our later studies, we will be modifying same; to date the scores did not deviate by more than one point (to two points) over a score of ten!

Download the entire Project H-1 report titled, Benthic Macroinvertebrates in Freshwaters- Taxa Tolerance Values, Metrics, and Protocols, dated June, 2002.  click for info on PDF documents


Modified Biotic Index (BI)

(Plafkin et al., 1989; Mackie, 2000)

........... is a more rigorous bioassessment technique based on specific (i.e., species) levels mostly in order to allow detection of more subtle degrees of impairment!

The index has been modified to include non-arthropod species as well on the basis of the biotic index used by the State of New York (Bode et al., 1991, 1996). Although the HBI may be applicable for other types of pollutants, it has only been evaluated for organic pollutants. The formula for calculating the Biotic Index is:

BI = Σ(xi*ti)/(n), where

xi = number of individuals within a species
ti = tolerance value of a species
n = total number of organisms in the sample (100)

The following table is a general guide to the water quality of streams. Replicate samples, or both spring and fall samples, will add to the confidence of the evaluation.


Table-3: Evaluation of water quality using biotic index values of samples collected in March, April, May, September, and early October (Hilsenhoff, 1987)
Biotic IndexWater Quality Degree of Organic Pollution
0.00-3.50ExcellentNo apparent organic pollution
3.51-4.50Very goodPossible slight organic pollution
4.51-5.50GoodSome organic pollution
5.51-6.50FairFairly significant organic pollution
6.51-7.50Fairly poorSignificant organic pollution
7.51-8.50PoorVery significant organic pollution
8.51-10.00Very poorSevere organic pollution

Note: Hilsenhoff’s biotic index (1987) may require regional modification in some instances.



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