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Taxa Tolerance Values

Soil & Water Conservation Society of Metro Halifax (SWCSMH; limneschebucto.ns.ca)

Updated: June 18, 2015                  Chemical vs Biological monitoring

Contents

• Introduction

• RBP II: Tolerances based mostly on family levels (Table-1)
  • Table-2: Modified Family Biotic Index (FBI)

• RBP III: 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)

Introduction

Tolerance

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)

• Superphylum Arthropoda
• Phylum Entoma
• Subphylum Uniramia
• Class Collembola (springtails)
• Order Ephemeroptera (mayflies)
• Order Odonata (dragonflies and damselflies)
• Order Plecoptera (stoneflies)
• Order Hemiptera
(water or true bugs)
• 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

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

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	3
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)

............ 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

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

RBP III: Tolerance values based on species/generic levels

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

Modified Biotic Index (BI)

........... 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!

BI = Σ(x_i*t_i)/(n), where

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.

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