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Taxa Tolerance Values

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roche horizontal rule

Introduction
Tolerances based mostly on family levels (Table-1) ............ suitable as an initial assessment!

Table-2: Modified Family Biotic Index (FBI)

Tolerances based on species/generic levels ........... is a more rigorous bioassessment technique!

Table-3: Modified Biotic Index (BI)

The Federal DFO/Environment Canada's EMAN protocols for measuring biodiversity --- the preferred sampling methodologies
References
Our related finalised Reports (several others are in various stages of formulation)
Lead quotes

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.

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 nonconformance of the scores did not deviate by more than one point over a score of ten!

Superphylum Arthropoda
Phylum Entoma

Subphylum Uniramia

Class Collembola (springtails)
Order Ephemeroptera (mayflies)
Order Odonata (dragonflies and damselflies)
Order Plecoptera (stoneflies)
Order Hemiptera
Order Trichoptera (caddisflies)
Order Lepidoptera (butterflies and moths)
Order Coleoptera (beetles)
Order Megaloptera (fishflies, dobsonflies, alderflies)
Order Neuroptera (spongillaflies)
Order Diptera (Two-winged or "true flies")
- Family Chironomidae (non-biting or true midges)

Subphylum Chelicerata

Order Acariformes (water mites)
Class Diplopoda

Subphylum Crustacea

Order Isopoda (sow bugs)
Order Amphipoda (scuds; side swimmers)
Order Cumacea
Order Decopoda (shrimps, crabs, etc.)
Order Cladocera (water fleas)
Subclass Copepoda
Class Ostracoda (seed shrimps)

Phylum Mollusca
- Class Gastropoda (snails and limpets)
- Class Pelecypoda/Bivalvia (clams and mussels)
Phylum Annelida

Class Oligochaeta (aquatic worms)
Class Hirudinea (leeches and bloodsuckers)
Class Aphanoneura
Class Branchiobdellida (leech-like ectosymbionts)
Class Polychaeta (freshwater tube worms)

Phylum Platyhelminthes

Class Turbellaria (planarians/dugesia)

Phylum Coelenterata
Phylum Nemertea (ribbon worms)

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!
Taxon	Feeding Habit	Tolerance
Superphylum Arthropoda, Phylum Entoma
Subphylum Uniramia
Class Collembola (springtails)
Isotomurus sp.	c-g	5

Order Ephemeroptera (mayflies)
Ameletidae	c-g	0
Baetidae	c-g/scr	5
Baetiscidae	c-g	4
Caenidae	c-g	6
Ephemerellidae	c-g/scr	1
Ephemeridae	c-g	3
Heptageniidae	scr	3
Isonychiidae	c-f	2
Leptophlebiidae	c-g	3
Leptohyphidae	c-g	4
Metretopodidae		2
Oligoneuriidae		2
Polymitarcyidae	c-g	2
Potomanthidae	c-g	4
Siphlonuridae	c-g	4
Tricorythidae		4

Order Odonata (dragonflies and damselflies)
Aeshnidae	prd	3
Calopterygidae	prd	6
Coenagrionidae	prd	8
Cordulegastridae	prd	3
Corduliidae	prd	2
Gomphidae	prd	3
Lestidae	prd	6
Libellulidae	prd	2
Macromiidae	prd	2

Order Plecoptera (stoneflies)
Capniidae	shr	2
Chloroperlidae	prd/c-g	0
Leuctridae	shr	0
Nemouridae	shr	2
Peltoperlidae	shr	0
Perlidae	prd	2
Perlodidae	prd	2
Pteronarcyidae	shr	0
Taeniopterygidae	shr	2

Order Hemiptera (water or true bugs)
Corixidae (water boatmen?)	prd	5

Order Trichoptera (caddisflies)
Apataniidae	scr	scr
Brachycentridae	shr/c-f	1
Calamoceratidae		3
Dipseudopsidae	c-f	5
Glossosomatidae	scr	1
Goeridae	scr	3
Helicopsychidae	scr	3
Hydropsychidae	c-f	4
Hydroptilidae	scr/shr/c-g	4
Lepidostomatidae	shr	1
Leptoceridae	c-g/shr/prd	4
Limnephilidae	shr/scr/c-g	3
Molannidae	scr	6
Odontoceridae	scr	0
Philopotamidae	c-f	3
Phryganeidae	shr/prd	4
Polycentropodidae	c-f/prd	6
Psychomyiidae	c-g/scr	2
Rhyacophilidae	prd	1
Sericostomatidae		3
Uenoidae	scr	3

Order Lepidoptera (butterflies and moths)
Arctiidae	shr	5
Nepticulidae	shr	5
Pyralidae	shr/scr	5

Order Coleoptera (beetles)
Curculionidae	shr	5
Dryopidae	scr	5
Dytiscidae	prd	5
Elmidae	scr/c-g	4
Gyrinidae	prd	4
Haliplidae	shr	5
Hydrophilidae	c-g/prd/shr	5
Psephenidae	scr	4
Ptilodactylidae	shr	3
Scirtidae	scr	5

Order Megaloptera (fishflies, dobsonflies, alderflies)
Corydalidae (fishflies, dobsonflies, hellgrammites)	prd	4
Sialidae (alderflies)	prd	4

Order Neuroptera
Sisyridae (spongillaflies)
Climacia sp.	prd	5

Order Diptera (Two-winged or "true flies")
Anthomyiidae (root maggot flies)	prd	6
Athericidae	prd	4
Blephariceridae (net-winged midges)	scr	0
Ceratopogonidae (biting midges or no-see-ums)	prd	6
Chaoboridae (phantom midges)	prd	8

Family Chironomidae (non-biting or true midges)
Family Chironomidae, Blood-red (Chironomini)		8
Family Chironomidae, Other (including pink)		6
Subfamily Tanypodinae	prd	7
Subfamily Podonominae	c-g	1
Subfamily Diamesinae	c-g	2
Subfamily Prodiamesinae	c-g	7
Subfamily Orthocladiinae	c-g/shr/prd	6
Subfamily Chironominae	c-g/prd/shr/ c-f/scr	6

Culicidae (mosquitoes)	c-f	8
Dolichopodidae	prd	4
Dixidae (dixid midges)	c-f	1
Dolochopodidae		4
Empididae (dance flies)	prd	6
Ephydridae (shore flies, brine flies)	shr	6
Muscidae	prd	6
Psychodidae (moth flies)	c-g	8
Ptychopteridae	c-g	9
Scathophagidae (dung flies)	shr	6
Simuliidae (black flies)	c-f	6
Stratiomyidae (soldier flies)	c-g	7
Syrphidae		10
Tabanidae (horse and deer flies)	c-g/prd	5
Tanyderidae	c-g	3
Tipulidae (crane flies)	c-g/prd/shr	3

Subphylum Chelicerata
Class Arachnida
Order Acariformes Arachnoidea (water mites)
Arrenuridae	prd	6
Lebertiidae	prd	6
Atractideidae	prd	6
Mideopsidae	prd	6
Tyrellidae	prd	6
Limnesidae	prd	6
Limnocharidae	prd	6
Sperchonidae	prd	6
Unionicolidae	prd	6

Class Diplopoda Polydesmida	c-g	6

Subphylum Crustacea
Order Isopoda (sow bugs)	c-g	8
Anthuridae	c-g	5
Idoteidae	c-g	5
Asellidae	c-g	8

Order Amphipoda (scuds; side swimmers)	c-g	4-8
Crangonyctidae	c-g	6
Gammaridae	c-g	6
Oedicerotidae	c-g	5
Talitridae/Hyalellidae	c-g	8

Order Cumacea	c-g	5

Order Decapoda (shrimps, crabs, etc.)	c-g	6

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-g	8

Phylum Mollusca
Class Gastropoda (snails and limpets)	scr	7
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-f	8
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
Lumbricida	c-g	6
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)
Sabellidae	c-g	6

Phylum Platyhelminthes
Class Turbellaria (planarians/dugesia)	prd	4
Platyhelminthidae		4

Phylum Coelenterata
Hydridae
Hydra sp.	prd	5

Phylum Nemertea (ribbon worms)
Tetrastemmatidae
Prostoma graecense	prd	8

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(x_i*t_i)/(n), where

x_i = number of individuals within a taxon
t_i = 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 Index Water Quality Degree of Organic Pollution

0.00-3.75 Excellent Organic pollution unlikely

3.76-4.25 Very good Possible slight organic pollution

4.26-5.00 Good Some organic pollution probable

5.01-5.75 Fair Fairly substantial pollution likely

5.76-6.50 Fairly poor Substantial pollution likely

6.51-7.25 Poor Very substantial pollution likely

7.26-10.00 Very poor Severe organic pollution likely

Note: Hilsenhoff’s family-level biotic index (1988) may require modification for some regions

**Table-2: Evaluation of water quality using the family-level biotic index (Hilsenhoff, 1988)**
Family Biotic Index	Water Quality	Degree of Organic Pollution
0.00-3.75	Excellent	Organic pollution unlikely
3.76-4.25	Very good	Possible slight organic pollution
4.26-5.00	Good	Some organic pollution probable
5.01-5.75	Fair	Fairly substantial pollution likely
5.76-6.50	Fairly poor	Substantial pollution likely
6.51-7.25	Poor	Very substantial pollution likely
7.26-10.00	Very poor	Severe organic pollution likely

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 nonconformance of 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 in PDF format. This report contains a overview of the subject of biotic monitoring over and above the family as well as the species level tolerance values. If you do not have the free Adobe Acrobat Reader, click on

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(x_i*t_i)/(n), where

x_i = number of individuals within a species
t_i = 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 Index Water Quality Degree of Organic Pollution

0.00-3.50 Excellent No apparent organic pollution

3.51-4.50 Very good Possible slight organic pollution

4.51-5.50 Good Some organic pollution

5.51-6.50 Fair Fairly significant organic pollution

6.51-7.50 Fairly poor Significant organic pollution

7.51-8.50 Poor Very significant organic pollution

8.51-10.00 Very poor Severe organic pollution

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

**Table-3: Evaluation of water quality using biotic index values of samples collected in March, April, May, September, and early October (Hilsenhoff, 1987)**
Biotic Index	Water Quality	Degree of Organic Pollution
0.00-3.50	Excellent	No apparent organic pollution
3.51-4.50	Very good	Possible slight organic pollution
4.51-5.50	Good	Some organic pollution
5.51-6.50	Fair	Fairly significant organic pollution
6.51-7.50	Fairly poor	Significant organic pollution
7.51-8.50	Poor	Very significant organic pollution
8.51-10.00	Very poor	Severe organic pollution

References

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