Committee on the Status of Species at Risk in Ontario (COSSARO)
Assessed by COSSARO as Endangered
May 2012

Final

Part 1 - Current status and distribution

Current designations:

GRANKG3 (NatureServe, 2012)
NRANK Canada – N1N2 (NatureServe, 2012)
COSEWIC – Endangered (COSEWIC, 2012b), assessed 2002
SARA – Endangered (Schedule 1) (Environment Canada, 2012) ESA 2007 – Endangered (Ministry of Natural Resources, 2012)
SRANKS1 (NHIC, 2012)

Distribution in Ontario:

Restricted to southwestern Ontario (Lake St. Clair, St. Clair River, Detroit River, and Thames River in Lambton, Essex, Middlesex and Elgin Counties) which is near the northern limit of the species’ range (COSEWIC, 2012a).

Distribution and status outside Ontario:

Northern Madtom is endemic to eastern North America and is ranked by NatureServe (2012) as G3 (vulnerable). In Canada, it occurs only in southwestern Ontario. In the US, it occurs sporadically from Illinois, Michigan, and Pennsylvania, south to Kentucky and West Virginia (COSEWIC, 2012a).

Part 2 - Eligibility for Ontario status assessment

2.1 Application of eligibility criteria

Taxonomic distinctness

Yes. Northern Madtom is considered a valid species in almost all recent taxonomic works. This species is closely related to the Frecklebelly Madtom (Noturus munitus) which occurs only in the United States (COSEWIC, 2012a).

Designatable units

No subspecies or varieties have been described for Northern Madtom. The species is known in Ontario only from a small part of the southwest with no significant range disjunctions. Only a single designatable unit is recognized based on its restricted range in southwestern Ontario. No genetic information is available on the Ontario populations.

Native status

Yes. Considered to be a native fish in southwestern Ontario since it was first reported in the province in Lake St. Clair in 1963 (COSEWIC, 2012a).

Presence/absence

Present. Four Ontario populations considered extant were confirmed between 2007 and 2010 (COSEWIC, 2012a).

2.2 Eligibility results

  1. The putative taxon or DU is valid. Yes
  2. The taxon or DU is native to Ontario. Yes
  3. The taxon or DU is present in Ontario, extirpated from Ontario or extinct? Present

Part 3 - Ontario status based on COSSARO evaluation criteria

3.1 Application of primary criteria (rarity and declines)

1. Global rank

Threatened. G3 (NatureServe, 2012)

2. Global decline

Not in any category. No evidence of a major global decline and some evidence of increases on the US side of the Detroit River (NatureServe, 2012; COSEWIC, 2012a).

3. Northeastern North America ranks

Endangered. The species is ranked in 8 of the 8 jurisdictions where it occurs (100%). Northern Madtom is highly ranked (S1, S2, SH, or SX) in 7 of 8 jurisdictions (88%) (NatureServe, 2012).

4. Northeastern North America decline

The northeastern North American range of the species is largely the same as its global range (COSEWIC, 2012a) and therefore no classification provided.

5. Ontario occurrences

Endangered. There are four extant locations (confirmed between 2007 and 2010) and a fifth that is rated as extirpated (COSEWIC, 2012a). Capture rates at most sites are low (COSEWIC, 2012a).

At the location that is regarded as extirpated (the Sydenham River), Northern Madtom was recorded only once in 1975. An earlier fish specimen (taken in 1929) from the Sydenham River may be a Northern Madtom but its identity is uncertain (COSEWIC, 2012a). Extensive surveys were conducted at many sites along the river between 1997 and 2010 but no Northern Madtom were found (COSEWIC, 2012a). This location may not have had a self-sustaining population but the single collection may have been from an accidental introduction―possibly by a fisherman (Edwards et al., 2012).

The Lake St. Clair population (where Northern Madtom was first discovered in Canada) is known from observations of only one to a few individuals in 1963, 1996, 1999, and 2007 (COSEWIC, 2012a). None was found during surveys at eight sites in 2010.

Sampling in the Detroit River between 1994 and 2010 found Northern Madtom at several sites where up to 69 individuals were captured (COSEWIC, 2012a).

Northern Madtom were collected in small numbers at several sites along the St. Clair River in 2003 and 2010, which is a new location since the 2002 COSEWIC Status Report (COSEWIC, 2002).

At several sites along the Thames River, Northern Madtom has been collected in very small numbers between 1991 and 2010 (COSEWIC, 2012a).

6. Ontario decline

Insufficient information. Sampling effort and methodology have been too variable and inconsistent to allow Northern Madtom population trends to be identified (COSEWIC, 2012a). One new location (St. Clair River) and additional subpopulations at two of the known locations (Detroit River and Thames River) have been found since the 2002 COSEWIC Status Report (COSEWIC, 2002). This apparent expansion is likely due to increased and targeted sampling effort (COSEWIC, 2012a). Recent targeted surveys at some of the known sites in the lower Thames River and in Lake St. Clair have failed to find any Northern Madtom (COSEWIC, 2012a).

7. Ontario’s conservation responsibility

Not in any category. Ontario makes up <10% of the species global range (COSEWIC, 2012a).

3.2 Application of secondary criteria (threats and vulnerability)

8. Population sustainability

Insufficient information. No population viability analyses have been conducted for the species (COSEWIC, 2012a).

9. Lack of regulatory protection for exploited wild populations

Not in any category. Fish habitat is protected under the Fisheries Act, which gives the Northern Madtom some protection. Other protective legislation in Ontario includes the Endangered Species Act, 2007 and the Species at Risk Act (MNR, 2012). The species is not known to be exploited in the province.

10. Direct threats

Threatened. The primary threats identified for Northern Madtom include siltation, water turbidity, excessive nutrient loading, exotic species, toxic compounds, and habitat loss/degradation (COSEWIC, 2012a). For each of the four extant populations, most of these factors are considered widespread, continuous, and of medium or high concern (COSEWIC, 2012a). Remedial steps have been undertaken in the Detroit River to improve water quality and increase the amount of fish habitat (COSEWIC, 2012a). These include shoreline rehabilitation, the installation of artificial spawning reefs, and the removal of contaminated sediments. Steps have also been taken in the St. Clair River to reduce the inflow of untreated sewage (COSEWIC, 2012a).

11. Specialized life history or habitat-use characteristics

Not in any category. Northern Madtom may have narrow but undescribed habitat tolerances considering its limited range and extent in Ontario (COSEWIC, 2012a; Dextrase, 1997). Its short lifespan and reduced fecundity may place some populations at long-term risk (Edwards et al., 2012).

3.3 COSSARO evaluation results

1. Criteria satisfied in each status category

Number of primary and secondary criteria met in each status category:
Endangered – 2/0
Threatened – 1/1
Special Concern – 0/0

Number of Ontario-specific criteria met in each status category:
Endangered – 1
Threatened – 1
Special Concern – 0

2. Data deficiency

No. Two criteria are assessed as “insufficient information”, however, there is enough information in the other categories to assess status.

3. Status based on COSSARO evaluation criteria

The application of COSSARO evaluation criteria suggests that Northern Madtom is Endangered in Ontario.

Part 4 - Ontario status based on COSEWIC evaluation criteria

4.1 Application of COSEWIC criteria

Regional (Ontario) COSEWIC criteria assessment

Criterion A – Decline in total number of mature individuals

Insufficient information. Number of mature individuals in Ontario is unknown (COSEWIC, 2012a).

Criterion B – Small distribution range and decline or fluctuation

Endangered. Meets B1ab(iii) and B2ab(iii) Extent of Occurrence is <5,000 km2 (3330 km2) and Area of Occupancy is <500 km2 (180 km2 based on 2 km x 2 km grid and 107 km2 based on 1 km x 1 km grid). The Northern Madtom is known from <5 sites and there is an inferred decline in habitat quality (COSEWIC, 2012a).

Criterion C – Small and declining number of mature individuals

Insufficient information. Number of mature individuals and population trend is unknown (COSEWIC, 2012a).

Criterion D – Very small or restricted total population

Threatened. Meets D2. There are five or fewer locations (COSEWIC, 2012a).

Criterion E – Quantitative analysis

Insufficient information. No population viability analyses have been conducted for the species in Ontario.

Rescue effect

Yes. Possible but unlikely. Imperiled or Critically Imperiled in three of the four closest states (Michigan: S1, Ohio: S1, and Pennsylvania: S2) and does not occur in New York (NatureServe, 2012). Mark-recapture studies in the Detroit River in 2009-2011 showed that adult Northern Madtom had crossed the river from the US to the Canadian side (Manny et al., 2012).

4.2 COSEWIC evaluation results

1. Criteria satisfied in each status category

Endangered – Yes
Threatened – Yes
Special Concern – No

2. Data deficiency

No. Data regarding population size and trends (on which many of the COSEWIC criteria are based) are lacking, however, there is enough information on range and habitat quality to allow a status determination.

3. Status based on COSEWIC evaluation criteria

The application of COSEWIC evaluation criteria suggests that Northern Madtom is Endangered in Ontario.

Part 5 - Ontario status determination

5.1 Application of COSSARO and COSEWIC criteria

COSSARO and COSEWIC criteria give the same result. Yes.

5.2 Summary of status evaluation

Northern Madtom is classified as Endangered in Ontario.

The Northern Madtom (Noturus stigmosus) is a small member of the catfish family that forages mostly at night. It has a mottled colour pattern, four pairs of barbels on the head, and venomous spines in dorsal and pectoral fins. This fish appears to be declining in much of its global range. In the United States, the Northern Madtom is found in the Ohio River, western Lake Erie, and the Lake St. Clair basins. In Canada, it is known only from the Detroit River, St. Clair River, Lake St. Clair, and the Thames River. It is likely extirpated from the Sydenham River where it was last recorded in 1975. Despite its rarity and limited range, the species occupies a wide range of habitats from small creeks to the shores of the Great Lake The maximum age for the species is three years. Potential threats to Northern Madtom include siltation of its habitat, excessive turbidity and nutrient loading, exotic species, toxic compounds, and habitat loss or degradation. Most of these threats relate to agricultural and urban land uses that dominate the species range. The Northern Madtom is considered endangered in Ontario and imperiled or critically imperiled in most of its US range.

Information sources

1. Literature cited

COSEWIC. 2002. COSEWIC Assessment and Update Status Report on the northern madtom, Noturus stigmosus, in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vii + 15 pp.

COSEWIC. 2012a. COSEWIC Status Report on Northern Madtom Noturus stigmosus in Canada. Prepared for Committee on the Status of Endangered Wildlife in Canada. 2-month Interim Report. 48 pp.

COSEWIC, 2012b. COSEWIC web site. Last updated March 2012. http://www.cosepac.gc.ca

Dextrase, A.J. 1997. COSSARO Candidate V, T, E Species Evaluation Form for Northern Madtom Noturus stigmosus. Prepared for the Committee on the Status of Species at Risk in Ontario (COSSARO), 5 pp.

Edwards, A.L., A.Y. Laurin, and S.K. Staton. 2012. Recovery strategy for the Northern Madtom (Noturus stigmosus) in Canada [Proposed]. Species at Risk Act Recovery Strategy Series. Fisheries and Oceans Canada, Ottawa, Ontario. viii +42 pp.

Environment Canada, 2012. Species at Risk Public Registry web site. http://www.sararegistry.gc.ca/default.asp?lang=En&n=24F7211B-1.

Manny, B., B.A. Daley, J.C. Boase, and A.N. Horne. 2012. Occurrence and movements of the endangered Northern Madtom (Noturus stigmosus) in the Detroit River, 2003-2011. Manuscript submitted to Journal of Great Lakes Research.

NatureServe, 2012. NatureServe web site. Last updated February 2012. http://www.natureserve.org/explorer/.

NHIC, 2012. Natural Heritage Information Centre Biodiversity Explorer web site. /page/natural-heritage-information-centre

Ministry of Natural Resources, 2012. Species at Risk for Ontario web site. /page/species-risk.

2. Community and Aboriginal traditional knowledge sources
No community knowledge or traditional Aboriginal knowledge was available.

3. Acknowledgements
Scott Gibson from the OMNR COSSARO Secretariat located important information.

Appendix 1

Northeastern North America status rank and decline

 Subnational RankSourcesDeclineSources
CTNot presentNatureServe 2012  
DENot presentNatureServe 2012  
ILS1NatureServe 2012  
INSNatureServe 2012  
IANot presentNatureServe 2012  
LBNot presentNatureServe 2012  
KYS2S3NatureServe 2012  
MANot presentNatureServe 2012  
MBNot presentNatureServe 2012  
MDNot presentNatureServe 2012  
MENot presentNatureServe 2012  
MIS1NatureServe 2012  
MNNot presentNatureServe 2012  
NBNot presentNatureServe 2012  
NFNot presentNatureServe 2012  
NHNot presentNatureServe 2012  
NJNot presentNatureServe 2012  
NSNot presentNatureServe 2012  
NYNot presentNatureServe 2012  
OHS1NatureServe 2012  
ONS1NatureServe 2012  
PAS2NatureServe 2012  
PENot presentNatureServe 2012  
QCNot presentNatureServe 2012  
RINot presentNatureServe 2012  
VANot presentNatureServe 2012  
VTNot presentNatureServe 2012  
WINot presentNatureServe 2012  
WVS1NatureServe 2012  

Occurs as a native species in 8 of 29 northeastern jurisdictions.
SRANK or equivalent information available for 8 of 8 jurisdictions = 100% S1, S2, SH, or SX in 7 of 8 = 88%