Fishes of Canada's National Capital Region
Species Accounts
Ictaluridae - North American Catfishes - Barbottes et Barbues
Bullhead or North American freshwater catfishes are found from southern Canada to Guatemala. There are about 45 species with 10 recorded from Canada and 6 in the NCR.
This is the only catfish family in Canada and is easily recognised by the scaleless skin, 8 barbels (2 on the nostrils, 2 at the upper jaw corners and 4 on the chin) and the dorsal and pectoral fins with a spine at the front. There are usually 6 dorsal fin soft rays. The palate lacks teeth. An adipose fin is present. In the United States some members of this family exceed 1.3 m and 45 kg.
They are related to the Carp and Sucker families which also have the chain of bones connecting the swimbladder to the ear. Important identification features are the nature of the pectoral spine and the number of anal rays. Ray counts include all rays, even rudimentary ones and a needle and some dissection may be required. Also important are pore numbers on the head and colour pattern.
Bullheads show a variety of interesting behaviours. All species construct nests and protect their young, although some smaller species take advantage of pollution by nesting in beer cans. Some species can recognise other fish individually by smell and even determine their social status. Chemical "strangers" are subject to aggression. Home sites are also recognised by substrate chemical marks applied by the fish. Territories may be marked chemically in this way. The nostrils are very sensitive to pheromones, hormones released into the water in urine, from the skin and from various glands. The barbels and skin are taste- and touch-sensitive and used to detect food. This is particularly useful in muddy water and at night. Many of these catfishes are nocturnal. "Taste" can also be used in breeding behaviour and in schooling. A Weberian apparatus, modified vertebral bones connecting the brain and swimbladder, are used to transmit sound and bullhead hearing is excellent. Some species can be trained to respond to names!
Catfish lack scales and are aged by making cross sections of pectoral spines to read growth rings. The fin spines can be very toxic because of poisonous cell secretions on the sheath of the spine. Wounds can be painful and extremely swollen for days although in most cases the wasp-like sensation fades after an hour and is gone in about 4-5 hours. Madtoms are named for their hyperactive, darting and dashing behaviour and perhaps stinging effect but even the bullheads (Ameiurus and Ictalurus species) can inflict an uncomfortable, poisoned wound. The spines are an effective defense mechanism for these catfishes but are not fatal to humans. All catfishes should be handled with care. The spines in the dorsal and pectoral fins can be locked in an erect position by an unique arrangement of muscles attached to the spine and associated bones. Bullhead catfishes are hardy and very tolerant of domestic pollution. Larger catfishes, such as the Channel Catfish, are commercially important in the U.S.A. and are cultured in ponds. Catfish restaurant dinners are a specialty in the southern U.S.A. and catfish figure prominently in fish and chips. These fishes are also sought after by anglers, being strong fighters and good eating. Smaller specimens and species have been used in the aquarium trade. They have been introduced outside North America.
A map record for Ameiurus melas (Rafinesque, 1820)(Black Bullhead, Barbotte noire) in the NCR by Mandrak and Crossman (1992) needs confirmation.
Yellow Bullhead / Barbotte jaune
Ameiurus natalis (Lesueur, 1819)
Taxonomy
Other common names include Northern Yellow Bullhead, Yellow Catfish, Creek Cat, White Whiskered Bullhead, Greaser, Polliwog, Yellowbelly Bullhead, Butterball, Buttercat, Paper Skin, Slick Bullhead and Mississippi Bullhead. Formerly in the genus Ictalurus.
Key Characters
This species is identified by the posterior tip of the adipose fin being free of the back, the caudal fin is not deeply forked, mouth corner barbels are about twice as long as nostril barbels, there is no bony ridge between the head and the dorsal fin, the anal fin touches the caudal fin when pressed to the body, chin barbels are yellow to white or pinkish, upper barbels are yellow to grey and the caudal fin is rounded.
Description
Dorsal fin soft rays 6, total anal rays 24-28, pelvic rays 8 and pectoral rays 7-8. The barbs on the dorsal fin spine are very weak. The pectoral spine has strong barbs in young fish but these do not grow with the fish and are weak in large fish. Gill rakers 12-15.
Colour
The back and top of the head are olive-brown to blackish, sometimes grey or even yellow, the flanks are yellowish without mottles and the belly is yellow to white. Fins are brown or olive to dusky with the thicker bases darker. The anal fin may have a central stripe. The adipose fin tip may be pale. Young fish are jet black above and white below with white chin barbels.
Size
Reaches 46.5 cm. The world, all-tackle angling record weighed 1.92 kg and was caught in 1984 in Mormon Lake, Arizona.
Distribution
Found in southern Ontario and Québec from the St. Lawrence River basin west through lakes Ontario, Erie, St. Clair and southern Huron to North Dakota and south to the Gulf of Mexico. It may be more common in the NCR than records indicate as it is often confused with the Brown Bullhead (Phelps, 2001). Conversely, Brown Bullheads have been mis-identified as this species.
Origin
This species entered the NCR from possibly an Atlantic coastal or a Mississippian refugium (Mandrak and Crossman, 1992).
Habitat
Yellow Bullheads are found in still or slow waters of lakes, ponds and rivers where there is a lot of vegetation and sand to silt bottoms. They may be found in slow riffles. Their preferred temperature is 28.3°C. They are tolerant of some pollution compared to Black and Brown Bullheads but less tolerant of turbidity. These bullheads are active at night.
Age and Growth
Life span is 7 years with maturity attained at 2-3 years.
Food
Scavenging for crustaceans, insects, molluscs, worms and less frequently macrophytes and fishes takes place at night. Older fish specialise on crayfish and fish in Lake Opinicon, Ontario. Young fish travel in large schools feeding generally on whatever is available.
Reproduction
Spawning occurs in May to July after both sexes construct a nest. The nest is an open depression on a stream bed, a short burrow in a stream bank or under a rock or log, or a deserted muskrat burrow. Eggs are cream, adhesive, up to 3.0 mm in diameter and laid in batches of up to 700. A female may contain up to 7000 eggs. The male guards the nest and the young until they reach 51 mm.
Importance
The flesh of this species is white and tasty and it is caught occasionally by anglers using baited hooks and incidentally in commercial fisheries.
Brown Bullhead / Barbotte brune
Ameiurus nebulosus (Lesueur, 1819)
Taxonomy
Other common names include Northern Brown Bullhead, Mudcat, Mudpout, Horned Pout, Brown Catfish, Marbled Bullhead, Common Bullhead, Speckled Cat, Bullpout, Minister, Mud Cat, Creek Cat, Red Cat, Wooly Cat, Schuylkill Cat, Sacramento Cat. Formerly in the genus Ictalurus.
Key Characters
This species is identified by the posterior tip of the adipose fin being free of the back, the caudal fin is not deeply forked, mouth corner barbels are about twice as long as nostril barbels, there is no bony ridge between the head and the dorsal fin, the anal fin does not touch the caudal fin when pressed to the body, all barbels are dark brown to black, pectoral spine teeth strongly developed and numbering 4-9, total anal rays usually 20-24, gill rakers 10-16, caudal fin base dusky to dark, the dorsal fin membranes are not particularly dark, and the caudal fin is truncate.
Description
Dorsal fin soft rays 6-7, and pelvic rays 8. The dorsal fin spine has weak to absent teeth on barbs. Occasionally deformed specimens have been caught in the Ottawa River (Coad et al., 1974). These include s-shaped vertebral columns and major fusion of vertebrae resulting in a markedly shortened body. The causes are unknown.
Colour
The head, back and upper flanks are blue-black to yellow-brown or olive. There may be a violet iridescence. The flanks are lighter and may be mottled brown. The belly is yellowish to white. Barbels are dark brown to black. Fins are similar in colour to the adjacent body with some membranes darker. Faber (1984c) illustrates a larva.
Size
Reaches 53.2 cm. The world, all-tackle angling record weighed 2.49 kg and was caught in 1975 in Veal Pond, Georgia.
Distribution
Found in southern Nova Scotia, New Brunswick and Ontario, the extreme south of Québec, Lake of the Woods, southern Manitoba and southeastern Saskatchewan. Introduced to British Columbia in the lower Fraser River and southern Vancouver Island. In the U.S.A. south to Florida and Alabama. Widely introduced elsewhere in North America and Eurasia.
Origin
This species entered the NCR from a Mississippian, Missourian or an Atlantic coastal refugium. The presence of this species in Gatineau Park may be from introductions (Rubec, 1975a).
Habitat
This nocturnal bullhead lives in the shallow, weedy, warm waters of ponds, bays in lakes and river backwaters. Fish usually stay in a limited area but may migrate 16.1 km downstream in the Ottawa River. Bottoms are usually sand or mud with sunken logs down to about 12 m and this fish may burrow into mud to escape poor environmental conditions. A fish kill involving this species was noted at Mud Lake, Britannia Woods on 12 April 1984 probably from oxygen depletion under ice (Halliday, 1985). However it is tolerant of pollution, low oxygen and high temperatures (over 36°C, preferred temperature is 24.9-27.3°C). Rubec and Qadri (1982) report it as more abundant below industrial and municipal effluents in the Ottawa River near Ottawa. These effluents create turbid conditions that perhaps favour the touch-sensitive bullheads over visual feeders. However fish were in poorer condition and had slower growth where wood fibres from paper mills cover the bottom in the Ottawa River. Wood fibres limit invertebrate production and thus the areas suitable for bullheads to feed in. Numbers of bullheads can be high and below Ottawa they comprise 86% of the fish catch by number and 68% of the biomass with concentrations as high as an estimated 7785 fish per hectare in a bay on Kettle Island. Trap-nets set at the mouth of the bay in the early 1970s caught so many bullheads that they could not be hauled in and the net had to be cut to allow fish to escape. The construction of the Carillon Dam backed up water as far as Ottawa, flooding large areas and creating marshes ideal for bullheads below Ottawa. Bullheads in Lac LaPêche in Gatineau Park had markedly less pollutants (PCBs) in white muscle than fish from the St. Lawrence River east of Cornwall (Otto and Moon, 1996). Aggregations of bullheads have been seen prior to spawning, one during early May near Rockland in the Ottawa River being 45 by 27 feet in size. Some bullhead were observed to jump 2-3 feet out on the water (Rubec, 1975b). In the Spencerville Reach of the upper South Nation River, this bullhead dominated the hoop-net catch at 59% of the total catch (Lauzon, 2003).
Age and Growth
Maturity is attained mostly at age 3 and about 20-33 cm and life span is 18 years. Around Ottawa in the Ottawa River fish reach 9 years and populations had both fast- and slow-growing individuals (Rubec and Qadri, 1982). Some females mature as early as age 2. Males grow faster than females near Montréal and the population there includes both a slower and a more rapidly growing group. Stunted populations occur in poor environments where food is lacking and temperatures are low.
Food
Food is taken mostly at night aided by the sensitive barbels in an opportunistic manner. Gunn (1976) found that these catfish fed heavily in the early morning hours in the Ottawa River. Food includes crustaceans, insects, worms, molluscs, and less frequently algae and fishes. In the Ottawa River algae often comprise more than 60% of the diet, especially in summer, and include Spirogyra, Ulothrix, Oscillatoria and Fragilaria species. Experimental studies have shown about 24-67% of the carbon in the algae is digested as food and is an important energy source (Gunn, 1976; Gunn et al., 1977). Bullheads may eat duckweed, gulping this plant at the water surface in contrast to their normal bottom feeding. Bullheads also scavenge for waste and dead organisms and eat the eggs of commercially important species such as Lake Trout, although their impact on trout populations is probably not highly significant. Brown Bullheads are known to eat Pumpkinseeds. Walleye, Sauger, Northern Pike and Yellow Perch eat bullheads.
Reproduction
Spawning occurs in May to July in Canada at a water temperature over 20°C. In the NCR spawning occurs in about the third week of June at depths of 6 inches (15.2 cm) to 4 feet (1.22 m). A dominant male establishes a territory and prior to spawning fish caught in the Ottawa River show whitish scratches and teeth marks (Rubec, 1975b). The male and/or female, usually the latter, excavates a nest in mud, sand, among plant roots or in a burrow in a bank. Pebbles may be carried away in the mouth. The spawning pair touch and caress each others barbels and come to lie head to tail. Pale cream, adhesive eggs are shed and fertilised at intervals. Up to 13,800 eggs are recorded from 1 female, with fecundity in the Ottawa River reaching 8823 eggs (Rubec, 1975b). Both parents guard, fan and manipulate the ball of eggs, although Rubec (1975b) observed only the male doing this. Manipulation includes stirring with the barbels or fin spines and even picking up with the mouth and spitting out. Manipulation is essential for hatching. Larvae are 6.0-8.0 mm long at hatching. The young bullheads travel in a school for several weeks until they are about 5 cm long when they disperse. Either or both parents guard the school. These schools or catfish balls can number in the many hundreds and a ball can by walked through, parting and reforming behind one.
Importance
The flesh is red to pink and is excellent eating. Bullheads are easy to catch on worms, minnows, shrimps and cut meat. The Ontario Ministry of Natural Resources publishes a print and on-line "Guide to Eating Ontario Sport Fish" (www.mnr.gov.on.ca/MNR/) and has advisory limits for eating this species in the Mississippi Lake and River, Rideau River, South Nation River and Ottawa River. Environnement Québec also has recommended limits, in meals per month (1 to 8) for size of fish (small, medium or large), for such areas as Lac Deschênes at Aylmer and Quyon, Deschênes Rapids, the Ottawa River below Gatineau, above Hull, and at Masson, the Lièvre River above and below Buckingham and the Gatineau River at Chelsea, among others (www.menv.gouv.qc.ca, downloaded 13 October 2004). As these limits are apt to change, anglers consuming this fish should consult the most recent version.
In the U.S.A. they are used in pond culture. There are some minor commercial catches in Canada, mostly in Ontario. Dymond (1939) records catches from 1896 onward in the general vicinity of the NCR but trends cannot be determined as fisheries data is recorded from different areas at different dates and, in addition, includes some Channel Catfish. For example, in 1898 the catch was 55,850 lbs (25,356 kg) in the Ottawa River from Carillon to Pontiac in Québec, the highest recorded. In Ontario, the highest catch was in 1898 from Prescott and Carleton counties at 41,100 lbs (18,659 kg). McAllister and Coad (1975) report catches of about 100,000 lbs (45,500 kg) from the Ottawa River annually by commercial fishermen. Commercial fisheries for bullheads above and below Hull from the Québec side of the Ottawa River is documented by Pluritec (1982b). They occasionally appear in supermarkets in Ottawa as mudpout or barbotte. Barbotte suppers are held in the NCR by charitable organisations to raise funds. In 2005, the 5th Annual Pout Masters Catfish Tournament was held in Russell, Ontario in mid-May to raise funds for the Canadian Cancer Society. The Brown Bullhead has been used widely as an experimental animal to study uptake of pollutants and in physiological studies. Its introduction to waters where it is not native has severely affected other fishes through predation and competition.
Channel Catfish / Barbue de rivière
Ictalurus punctatus (Rafinesque, 1818)
Taxonomy
Other common names include Spotted Catfish, Great Lake Catfish, Lake Catfish, Northern Catfish, Blue Channel Cat, Lady Cat, White Cat, Fiddler, Willow Cat, Blue Fulton, Chucklehead and Hirondelle.
Key Characters
This species is identified by the posterior tip of the adipose fin being free of the back, a characteristic deeply forked caudal fin, mouth corner barbels more than 3 times as long as nostril barbels, and a bony ridge between the back of the head and the dorsal fin.
Description
Dorsal fin soft rays 6-7, total anal rays 23-32, pelvic rays 8 and pectoral rays 8-9. The dorsal fin spine lacks barbs while the pectoral spine has 16-20 strong barbs posteriorly. Gill rakers 13-18.
Colour
The back and upper flank are steel-blue, blue-grey, slate-brown or grey, fading to a whitish belly. Fins are similar to the adjacent body. Barbels are blackish. Males develop a swollen head above and behind the eyes in the spawning season, the bluish back colour is brighter and the belly is whitish-blue. Young fish, smaller than 35.6 cm, have olive to blackish dots on the flank and are greenish or silvery. An albino catfish, possibly a Channel Catfish, was caught on a worm in the Ottawa River at Treadwell just east of the NCR on the evening of 12 July 1999 and was returned there a few days later (N. Villeneuve, personal communication, 1999; Aubry, 1999). A "white catfish" was also caught in Constance Bay within the NCR in the early 1960s.
Size
Reaches 120.2 cm. The world, all-tackle angling record weighed 26.3 kg and was caught in 1964 in Santee-Cooper Reservoir, South Carolina. A 20.2 kg fish is reported from the Red River, Manitoba. Small (1883) found fish of 10 lbs (4.5 kg) and over only occasionally on the market in Ottawa. A Channel Catfish of 14 lbs (6.4 kg) was reported from the Ottawa River in April 2002 (www.fish-hawk.net, downloaded 20 May 2003) and fish to 40 lbs are reported from below the hydro dam at Fitzroy Harbour on the Ottawa River (www.neatpage.com/species.htm, downloaded 3 June 2003). The average size of Ottawa Valley "catfish", presumably this species, is given as 9 kg (www.ottawavalley.org/trivia/triv_pg.html, a cache downloaded 13 June 2003) while the Lac des Chats is reported as having fish in the 0.9-1.8 kg range with some larger fish at over 4.5 kg ( www.fishontario.com/articles/channel-cats/ontario.html, downloaded 20 June 2003). Smith (1974) found fish in the Ottawa River to reach 66.6 cm fork length.
Distribution
Found in extreme southern Québec, southern Ontario, Lake of the Woods, southeastern Manitoba and in the Qu'Appelle River and Cumberland Lake in eastern Saskatchewan. South to the Gulf of Mexico in the U.S.A. Widely introduced outside its natural distribution. In the major rivers of the NCR including the South Nation River (www.fish-hawk.net/gallery/misc/misc.htm?fuseaction=home.models&nav=4, downloaded 19 June 2003). More common above Ottawa-Hull than below.
Origin
This species entered the NCR from a Mississippian refugium.
Habitat
Channel cats are found in lakes and the larger rivers favouring deeper, cooler and clearer water than other bullheads. However they can survive temperatures up to 35°C although preferred temperature is 25.2°C. They are found as deep as 60 feet (18.3 m) in the Ottawa River (McAllister and Coad, 1975) over sand and rock bottoms. Channel Catfish were the predominant species in a nearshore community index netting of Lac des Chats (a section of the Ottawa River), making up 65.6% of fish sampled (Haxton, 1999). They usually spend the day in deep holes or under rocks and logs. In the St. Lawrence River some channel catfish do not move while others travel as much as 160 km and in the Red River in Manitoba as much as 350 km in 13 days. One fish tagged in the Ottawa River was caught 4 months later 16 km upriver (Smith, 1974). This fish is relatively absent downstream from Ottawa-Gatineau compared to upstream although 50 km downriver from the capital it is abundant enough to be commercially important. No clear reasons was discerned but pollution, food availability and competition with Ameirus nebulosus are possibilities (Smith, 1974). In Lac Deschênes of the Ottawa River, Haxton and Punt (2004) found densities of 3.5-6.4 fish/ha with estimated population size there at 38,445-69,609 fish. In Lac des Chats, which lies mostly outside the NCR upriver from Lac Deschênes, density was 29.4 fish/ha and abundance was 220,924 fish.
Age and Growth
Life span is about 40 years although few fish attain this. Maximum age in the NCR is 18 years but most are less than 13 years old (Smith, 1974; McAllister and Coad, 1975). Haxton and Punt (2004) aged fish to 26 years in the Ottawa River but this included fish from outside the NCR. Smith (1974) found fish in the Ottawa River showed similar growth for each sex, in both length and weight. All females were mature by age 6, before 33 cm fork length and 50% were mature at 5 years while all males were mature by age 11, before 45 cm fork length and 50% were mature at 6 years. This is older than in southern latitudes although the rate of increase in length was similar to other Canadian and American populations, even more southerly ones (Smith, 1974). A sample of 832 fish from Lac des Chats (Ottawa River section) had a mean total length of 47.4 cm and a weight of 1132 g, with a mean maximum length of 74.5 cm and a mean maximum weight of 5000 g (Haxton, 1999). These fish matured at total lengths over 40 cm, the smallest mature male being 42.1 cm and the smallest female 44.0 cm. Fish from Lac Deschênes had a mean length of 51.5 cm and a mean weight of 1539 g in one sample period, 48.5 cm and 1298 g in another (Haxton and Punt (2004). In Lake Erie half the females are mature at 25-28 cm and half the males at 28-31 cm. Growth is slower in the Ottawa River compared with other populations (Haxton and Punt (2004), probably due to very sporadic production of year classes and greatly reduced growth of older fish. Growth after 8 years of age is slow in Québec waters and maturity is attained there at 8 years at the northern range limit.
Catfish can be aged by the growth rings on spines which also reflect water temperatures since catfish do not feed and grow below certain temperatures. This knowledge gained from extant catfish has been used to determine the climate millions of years ago from deposits of fossil catfish spines.
Food
Feeding occurs both by day and by night and some items are taken at the water surface. Food includes crustaceans, aquatic and terrestrial insects, molluscs, algae and other plants, seeds, fish such as Yellow Perch, Pumpkinseeds, Mooneyes, Yellow Walleye, darters and minnows, and even birds, grapes, chicken necks, canned corn, beef bones and other scavenged items. In the Ottawa River, Smith (1974) found fish up to 30 cm fork length were insectivorous, from 30-45 cm omnivorous and above 45 cm piscivorous. The food consumed varied with seasonal availability and was taken mostly in aquatic vegetation. Channel cats elsewhere larger than about 80 cm feed almost exclusively on other fishes. Food in the Lac des Chats catfish included crayfish, insects, plants, juvenile Northern Pike, Walleye, Pumpkinseed and Smallmouth Bass (Haxton, 1999).
Reproduction
Spawning occurs in late spring to summer at 21-30°C; in the Ottawa River from late June to early July at 20.6-23.3°C (Smith, 1974). Some channel catfish move into running water at spawning. The male builds and cleans a nest, using fin and body movements, in holes under rocks, logs or in banks. Females bite other females or males when ready to spawn and both sexes drive other fish away. The female moves over the nest site, wiggling and banging the pectoral and pelvic alternately on the bottom. The male and female position themselves head to tail, wrapping their tails over each other's head, both fish quiver and release eggs and sperm. Eggs are yellow, up to 4.0 mm in diameter and up to 52,000 per female. In the Ottawa River average fecundity is 6480 eggs and average diameter 3.6 mm at spawning with maximum fecundity 11,500 eggs and diameter 4.18 mm (Smith, 1974). Males defend, aerate and manipulate the eggs. Manipulation is carried out with the body and fins and may serve to aid in hatching. The young fish are not herded as in bullheads.
Importance
Channel catfish have white, flaky flesh which has attracted a commercial fishery in Canada, and it is the principle catfish on farms in the U.S.A. in an attempt to meet demand. It is said to be one of the best tasting freshwater fishes in North America. The Canadian catch reached 564,322 kg in 1964. Dymond (1939) records catches from 1903, 1904 and 1907 in the NCR from the Ottawa River and tributaries (Pontiac and Ottawa counties) with weights of 11,600, 9000 and 8100 lbs (5266, 4086 and 3677 kg) respectively. McAllister and Coad (1975) report a commercial catch of 1000-2500 lbs (454-1135 kg) in the Ottawa River annually. Commercial fisheries for catfish above and below Hull from the Québec side of the Ottawa River is documented by Pluritec (1982b).
A 40 km stretch of the Ottawa River near Arnprior (Lac des Chats) was estimated to hold 252,350 fish (Haxton, 1999; Egan, 2002). The "Ottawa River Catfest" started in the year 2000 based in Arnprior and in 2002 over 3000 fish were caught by 500 anglers in the 3-day event. Fishing pressure in low in the Ottawa and the annual mortality of 15.7% is probably natural mortality (Haxton and Punt, 2004). This species is not an important sport fish in Ontario, despite "Catfest" and the Ottawa River population is underutilised (Haxton and Punt, 2004).
This catfish is an important sport species taken with live or dead bait, preferring the latter. It has even been caught using white soap as bait. Their large size, fighting abilities and tastiness make them attractive to anglers. The Ontario Ministry of Natural Resources publishes a print and on-line "Guide to Eating Ontario Sport Fish" (www.mnr.gov.on.ca/MNR/) and has advisory limits for eating this species in the Mississippi River, South Nation River and Ottawa River. Environnement Québec also has recommended limits, in meals per month (1 to 8) for size of fish (small, medium or large), for such areas as Lac Deschênes at Aylmer and Quyon, Deschênes Rapids, the Ottawa River below Gatineau, above Hull, and at Masson, the Lièvre River above and below Buckingham and the Gatineau River at Chelsea, among others (www.menv.gouv.qc.ca, downloaded 13 October 2004). As these limits are apt to change, anglers consuming this fish should consult the most recent version.
A fish kill, predominately of this species, in the Ottawa River, mostly above the Chats Falls Dam near Arnprior but also down to below Rockland (on a map, elsewhere to Petrie Island "near the town of Rockland"), took place in August 2006. It was attributed to an outbreak of columnaris disease (Ottawa Citizen, 20 August 2006, p. A3; Punt and Castro, 2006). The disease manifests as brown to yellow sores on the skin, fins and gills. Initially skin sores, for example, are very shallow and just appear as skin areas lacking the natural shiny appearance. Later this develops into round to oval lesions with an open ulcer in the centre. A characteristic lesion encircles the body as a pale white band, called a saddleback. Between 2000 and 4000 fish were killed. The disease is caused by Flavobacterium columnare, usually occurs in summer and is associated with stress, crowding, injury and poor water quality. In this case, high temperatures, torrential rain and extreme runoff events in late July and early August caused warm temperatures in the river and a stressed environment.
Stonecat / Barbotte des rapides
Noturus flavus Rafinesque, 1818
Taxonomy
Other common names include Stone Catfish, White Cat, Doogler, Beetle-eye, Mongrel Bullhead, Deepwater Bullhead and Little Yellow Cat.
Key Characters
This species is identified by the posterior tip of the adipose fin not being free but attached to the back, pectoral spine nearly straight to moderately curved, with or without anterior teeth, posterior edge smooth to roughened, and premaxillary band of teeth with lateral processes extending backwards.
Description
Dorsal fin soft rays 5-7, usually 6, anal rays 15-19, pelvic rays 8-10, usually 8, and pectoral soft rays 8-11, usually 10. There are 2 internasal pores.
Colour
The head, back and upper flank are dark bluish-olive, blue-black, olive, slate-grey or yellow-brown fading to cream, white or grey on the belly. The dorsal fin has a grey blotch at its base. The adipose fin is dark with a pale edge. Fin margins are light to white. There is a light yellow spot behind the dorsal fin across the back and a light blotch on the nape. The caudal fin has a white blotch on its upper margin. Chin barbels are white and upper barbels grey.
Size
Reaches 31.2 cm and 0.482 kg.
Distribution
Found in the Mississippi and Hudson river basins and the Great Lakes and Hudson Bay basins. In Canada in the southern Ontario basins of lakes Huron, Erie and Ontario and the upper St. Lawrence River basin of Ontario and Québec. It just enters Saskatchewan and Alberta in the Missouri River basin and in Manitoba is in the Assiniboine and Red River basins. A record of this species from the Ottawa River by Halkett (1913a) was based on "A very small specimen some 1¾ inches long passed from the Ottawa River through the water taps of the Ottawa fish hatchery in February, 1909".
Origin
This species entered the NCR from a Mississippian refugium.
Habitat
The favoured habitat of this species is riffles of streams and lake margins with water movement by wave action. It usually lives in the spaces between stones but may be found in stream mouths over mud and sand bottoms. It tends to be a solitary species.
Age and Growth
They may live 10 years. Females are mature at 4-5 years of age and males at 3 years.
Food
Food is mainly larval insects such as mayflies, and crustaceans, particularly crayfish, with molluscs, small fishes and algae. Feeding probably takes place at night. An aquarium specimen from the NCR fed on small guppies at night making a sharp clicking sound as it seized its prey (McAllister and Coad, 1975). Snakes and Smallmouth Bass are known to be successful predators despite the stinging pectoral fin spine.
Reproduction
Spawning occurs in summer (June to August) at high water temperatures (usually 27-29°C, but sometimes as low as 23°C in Manitoba). The male excavates a nest under a stone or under refuse such as cans, bottles and boxes. A sticky mass of about 100-500 eggs is laid under a stone and guarded by the male. Each female can produce up to 1205 yellow eggs of up to 4.0 mm diameter.
Importance
Stonecats have been used as bait for bass and catfishes. Their spines are venomous, painful but not fatal to humans. They are said to be quite tasty though rather small to eat.
Tadpole Madtom / Chat-fou brun
Noturus gyrinus (Mitchill, 1817)
Taxonomy
Other common names include Tadpole Stonecat and Tadpole Cat.
Key Characters
This species is identified by the posterior tip of the adipose fin not being free but attached to the back, pectoral spine nearly straight to moderately curved and without teeth, premaxillary band of teeth without lateral processes extending backwards, pectoral soft rays usually 7, but a range of 5-10, pelvic rays usually 8 but range of 5-10, mouth terminal, typically 10 preoperculomandibular pores, and vertical fins without a black margin.
Description
Dorsal fin soft rays 4-7, usually 6, anal rays 12-18, usually 15. There are 2 internasal pores. Body shape resembles a tadpole, hence the name. The anterior rays of the caudal fin are more strongly developed than in any other madtom.
Colour
The back and upper flank are olive-grey or brown to golden yellow, with the lower flank and belly light or with some pigmentation. Fins and barbels may be either darker or lighter than the adjacent body. The muscle segments of the body are darkly outlined and there is a dark line along the body axis. Breeding males are a dark chocolate brown or brownish-dusky.
Size
Attains 11.5 cm.
Distribution
Found in Atlantic coast drainages from New York to Florida, along the Gulf coast, in the Mississippi River basin and the southern Great Lakes basin. Absent from the mountains paralleling the Atlantic coast. In Canada found in southern Saskatchewan and Manitoba, the Quetico-Rainy River drainages of western Ontario which drain to Hudson Bay, tributaries of Lakes Huron, St. Clair, Erie and Ontario, and upper tributaries of the St. Lawrence River in Ontario and Quebec.
Origin
This species entered the NCR from possibly an Atlantic coastal or Mississippian refugium (Mandrak and Crossman, 1992).
Habitat
This madtom is found in quieter waters with slow current over mud bottoms with lots of vegetation such as wild celery and cattail beds in the Rideau River (Phelps et al., 2000). It may be found in both streams and lakes down to 25 m. It is nocturnal and hides in holes, debris or vegetation during the day but is quite common.
Age and Growth
Maximum age is 4 years. Males are larger and heavier than females in their fourth year of life. Some fish mature as early as 1 year and most by 2 years of age.
Food
Food is various aquatic insects and crustaceans. The toxin in the pectoral spine is capable of immobilising a Northern Pike.
Reproduction
Spawning occurs in summer (probably July in Canada) and eggs are laid in cavities or even tin cans. F. W. Schueler (in litt., 11 August 2004) found a ca. 70 mm adult in a 5 cm, roughly spherical nest under a stone with a carpet of newly hatched young on 8 July 1987 in Kemptville Creek just northwest of Oxford Mills at a water temperature of ca. 27ºC. Attempts to catch more advanced young in another nest were unsuccessful as they disappeared into the gravel. Eggs are yellow, up to 3.5 mm in diameter, but very variable in size, and are in an adhesive mass surrounded by a gelatinous envelope. Up to 150 eggs are found together, perhaps from more than 1 female. Clutches may be guarded by both male and female, or the male alone. Each female may contain up to 323 eggs but fecundity, like egg diameter, varies between populations.
Importance
This madtom has been used as bait for other fishes by anglers and is said to be excellent, despite the venomous pectoral spine.
Margined Madtom / Chat-fou liséré
Noturus insignis (Richardson, 1836)
Taxonomy
Another common name is Chat-fou livré.
Key Characters
This species is identified by the posterior tip of the adipose fin not being free but attached to the back, pectoral spine nearly straight to moderately curved, without anterior teeth, posterior teeth present, premaxillary band of teeth without lateral processes extending backwards, pectoral rays usually 9, pelvic rays usually 9, lower jaw included, 11 preoperculomandibular pores, and particularly the vertical fins with a black margin.
Description
Dorsal fin soft rays are 5-7, usually 6, anal rays number 15-21. Pectoral ray range is 7-10, pelvic ray range 8-10.
Colour
Overall colour is olive, slate-grey or yellowish fading to cream on the belly. Chin barbels are creamy white and other barbels dark. A narrow dark band crosses the belly in front of the pelvic fins. The dark band just below the edge of the dorsal, anal and caudal fins give this species its name. The extreme edge of these fins is clear. The pelvic fins are clear and the pectorals have a marginal band.
Size
Reaches 17.9 cm total length.
Distribution
Found in Atlantic coastal streams from New York south to Georgia, upper Ohio, Tennessee and Kanawha tributaries, southern tributaries of Lake Ontario. In eastern Ontario known from the Fall and Mississippi rivers and Bolton Creek in Lanark County near the NCR. It was first recorded from Canada in Gatineau Park in a stream draining Lac à la Loutre to Lac Lapêche (Rubec and Coad, 1974) and is now known from connected waterways in the Park and in the Gatineau River (www.fapaq.gouv.qc.ca, downloaded 7 October 2002). Also recorded between Hull and Lochaber, Hull County and between Lochaber and Montebello, Papineau County on the Québec side of the Ottawa River, and from the Cole Lake area near Buckingham (Phelps and Francis, 2002). In July 2005, this species was collected from the Mississippi River at Carleton Place and Appleton.
Origin
This species is used as a hardy bait fish in the U.S.A. so its recently recorded presence in Canada and the NCR may be the result of live release of specimens carried into Canada (Rubec and Coad, 1974; Coad, 1986a). There are documented records of bait fish introductions surviving in U.S.A. streams and so this is a plausible explanation for their appearance in Canada, especially since the Canadian localities are in popular areas for sport fishing. But it should be noted that there are restrictions on use of live bait fish in Ontario and Québec, although whether these would be followed in all cases by visitors from the south is debatable. Alternatively the species could have an origin from an Atlantic refugium after the last glaciation when a warmer climate existed than does today. Interconnecting postglacial lakes could have facilitated dispersal. It may also be a recent immigrant assisted by canals in the U.S.A. which have been shown to affect distributions. However the waterfall at Wakefield, Québec has been an effective recent barrier to dispersal into Gatineau Park for various fish species. Goodchild (1990a) reviews these possibilities and tentatively concludes that the species is indigenous to Canada and the NCR. The continued discovery of new localities for this species in the NCR suggests that it is spreading, which can argue for an introduction at one site in Gatineau Park, Québec and one on the Mississippi River in Ontario, followed by dispersion. Alternatively, the initial discovery can be seen as stimulating active searches for this species using appropriate equipment such as back-pack electroshockers, revealing distributions that existed before but were not apparent before. DNA studies currently under way may resolve the issue.
Habitat
It prefers clear streams with riffles of gravel and stones and in some cases with rocks and boulders and disappears when these silt up, e.g. after beavers dammed streams in Gatineau Park (Coad, 1986a). It is also recorded from a rubble shoal in Lake Joseph, Québec outside the NCR. This madtom is secretive and nocturnal. Numbers may be small at any one locality and this species can be easily over collected, removing the population at that locality. Coad (1986a) failed to find them using a seining technique that had been successful before but later, using an electroshocker was able to capture them in neighbouring localities in the same drainage. Lacoursière et al. (1989) failed to find any in Gatineau Park in their 1988 field study but their specimens were not seen by me. Wet specimens can survive several hours in air and this contributes to its use as a bait fish. However they are susceptible to the low oxygen concentrations found in late summer in pool areas of streams (Goodchild, 1990a). Laboratory hatching of eggs was optimal at 28-30ºC, and this may restrict distribution.
Age and Growth
Females are mature at 2 years, males a little earlier. Maximum age is 5 years. Most growth occurs in the summer after spawning.
Food
Food is insects, particularly those most active between midnight and dawn, crustaceans and, less frequently, fish, usually taken at night.
Reproduction
Adhesive eggs are deposited in a mass in a nesting cavity and are placed such that a current of water brings oxygen to them. The male cares for the eggs but may abandon or eat them if disturbed. Spawning occurs in June-July and females have up to 223 orange eggs with a diameter of 4.0 mm.
Importance
It was designated as "Threatened" in 1989 by the Committee on the Status of Endangered Wildlife in Canada (Goodchild, 1990a) but placed in the "Data Deficient" category because of insufficient scientific information in 2002. Lemieux (1986) recommended that it be given special attention in ecological analyses of Gatineau Park because of its rarity and apparent decline and Lacoursière et al. (1989) found none despite a specific effort to locate specimens. The fin spines are venomous but not fatal to humans.
© Brian W. Coad (www.briancoad.com)