Fishes of Canada's National Capital Region
Species Accounts
Gasterosteidae - Sticklebacks - Épinoches
Sticklebacks are found in coastal marine and fresh waters of the Northern Hemisphere. The number of species in the family is more than 7 with 5 named from Canada (but see below) and 3 in the NCR. The record by Small (1883) of the Fourspine Stickleback, Apeltes quadracus (Mitchill, 1815), in the NCR is an error as this is an Atlantic coast species and is, rare in fresh waters.
The family is characterised by 3-16 isolated spines in front of the soft dorsal fin, which has 6-14 rays, bony plates often present along the flank, the pelvic fin has 1 spine and 0-3 soft rays, caudal rays usually 12, slender caudal peduncle, small mouth with teeth, a swimbladder not connected to the gut, 3-4 branchiostegal rays, and various other osteological characters.
The number of species is uncertain and may not be readily explicable using the conventional, scientific naming system. The Threespine Stickleback as currently defined is a species complex containing populations which act as good species. This would require a major revisionary study given the great diversity shown by populations around the Northern Hemisphere. There is variation in colour, body form, maximum age (8 years as opposed to a usual 2-4 years), spine numbers and development, and plate numbers. These variations in anatomy are matched by variations in biology such as habitat, feeding and reproduction. In British Columbia, a centre for unusual sticklebacks, there is the giant Mayer Lake form, the unarmoured Boulton Lake form, the black Drizzle Lake form (all on the Queen Charlotte Islands), the Enos stickleback, and the Heisholt or Texada stickleback of Paxton, Priest, Emily and Balkwill lakes on Texada Island. The White Stickleback is the only unusual Atlantic coast form to receive detailed attention.
This variation in behaviour, biology and in speciation has attracted extensive studies by scientists and makes these small fishes, which have no commercial value, particularly important. Some of the variation is owing to environmental factors while some has a genetic basis. Several books have been devoted to them and thousands of scientific studies. Sticklebacks make excellent aquarium fishes. Their reproductive behaviour is complex, involving courtship and nest building. Some populations are anadromous and enter fresh water to breed.
Brook Stickleback / Épinoche à cinq épines
Culaea inconstans (Kirtland, 1840)
Taxonomy
Other common names include Five-spined, Black, Variable, Common, or Six-spined Stickleback and Pinfish.
Key Characters
This species is distinguished by having 4-7 short dorsal fin spines, no obvious bony plates on the flank and all spines are smaller than the eye diameter.
Description
Soft dorsal fin rays 8-13, soft anal rays 7-12 after 1 spine, pectoral rays 9-12 and pelvic fin with 1 spine and 1 soft ray. There are 30-36 tiny plates along the mid-flank. Many populations in Alberta lack part or all of the pelvic girdle and fin, and various populations across Canada show the occasional fish with reduced pelvic skeletons although this has not been found in the NCR
Colour
The back and flanks are olive-green, the flanks with lighter spots or short wavy lines. The belly is whitish-yellow or silvery-white. The dorsal and anal fin membranes are dusky. Breeding males are jet black, sometimes tinged with copper, and the pelvic fins have a red tinge. Females are a light green but develop a dark and light pattern when spawning. Peritoneum silvery with many melanophores. Faber (1984c) illustrates a larva.
Size
Reaches 8.7 cm fork length.
Distribution
Found from western Nova Scotia and New Brunswick west to northeastern British Columbia and the Mackenzie River basin. It is absent from northern Saskatchewan and Manitoba, Nunavut and the Yukon. In the U.S.A. south to Indiana and Nebraska and as a relict in New Mexico.
Origin
This species entered the NCR from a Mississippian refugium or possibly a Missourian refugium (Mandrak and Crossman, 1992).
Habitat
Brook Sticklebacks are found in small streams, bogs, ponds or lakes down to 55 m. The water is usually still or slow and bottoms are mud, detritus, sand gravel or rocks. The water can be clear or tea-coloured. They prefer heavy vegetation and are tolerant of low oxygen. Their preferred temperature is 21.3°C. These fish can spawn in temporary steams which can then dry up and strand them. Gas bubbles under ice in winter prolong survival of this fish since it can take advantage of a microlayer of water with higher oxygen next to the bubble. However in Kemptville Creek, large schools move upstream in spring to populate areas abandoned in winter on account of low oxygen levels (Schueler et al., 1992). Brook Sticklebacks may burrow into silt, remaining covered for more than half an hour. In some instances this behaviour is a search for food.
Age and Growth
Life span is 3 years at most and fish mature at 1 year. Most populations are annual fish which die after spawning in their second summer.
Food
Food is aquatic insects, crustaceans, snails, worms, algae, sponges and fish eggs and fry including those of Brook Sticklebacks. In Manitoba vegetated stream margins most feeding occurs between noon and 8:00 p.m. Feeding consists of five phases - swim, hover, aim, dart and handle. The hover or aim phases involve deciding whether to eat or reject the item seized. "Food fighting" occurs, especially under crowded conditions. Large food items are shaken apart and this causes up to 7 sticklebacks to compete for large food fragments. This process establishes a hierarchy among the fish. These sticklebacks are eaten by a variety of other fishes, leeches, birds, shrews, muskrats, and large larvae of water beetles and dragonflies. Pelvic spines protect against fish predators by increasing the size of mouth which can handle them. However water beetles seem to favour eating those sticklebacks with pelvic spines and are less successful at grasping spineless fish. This may be due to the closer approaches to the predator made by spiny fish; those lacking spines are more wary. Fish without spines compensate by a changed behaviour, perhaps taking more advantage of vegetation as shelter.
Reproduction
Spawning takes place from April to August at 4.5-21°C, usually at 8°C or warmer. Spawning is later in the north than the south. Males arrive on the spawning ground before females and build and defend nests. Ritualised displays against other males involve swimming parallel head to head or head to tail, fluttering their bodies and with spines erected. This is often followed by a quick attack. Males darken during this display and attack and develop black bands through their eyes. The nest is built on stems of vegetation near, or more rarely on, the bottom using dead and living fragments of vegetation, glued together with the white kidney secretions. The nest is a round barrel, up to 5.0 cm in diameter with a single opening. The male courts a female with nips, nudges and butts. Once she enters the nest he stimulates egg laying by prodding her belly and caudal peduncle. Eggs are yellow, adhesive and about 1.3 mm in diameter. Females produce on average up to 1926 eggs in a season in Manitoba, spawning 214 eggs every 3 days for 28 days. The female leaves the nest by pushing out, creating an exit hole which the male tries to repair. The female is driven away by the male. As more females are induced to spawn he enlarges his nest. The male looks after the eggs by fanning them with his pectoral fins. The young are also defended until they leave the nest. Larvae are 5.0-6.0 mm long at hatching.
Importance
This species has occasionally been used for bait in Québec.
Threespine Stickleback / Épinoche à trois épines
Gasterosteus aculeatus Linnaeus, 1758
Taxonomy
Other common names include Twospine, Common, Eastern, European or New York Stickleback; Banstickle, Panstickle, Pinfish, Tiddler, Kakilusuk, Kakilaychok, Katilautik and Kakilishek.
Key Characters
This species is distinguished by having usually 3 (range normally 2-4) dorsal fin spines, usually well-developed flank plates, 1 pelvic spine and 1 soft ray with a single cusp at the base, and colour.
Description
Second dorsal fin soft 7-14, anal fin with 1 spine and 6-11 soft rays, and 8-11 pectoral rays. Gill rakers number 23-25. Flank plates may be restricted to the anterior body under the first 2 dorsal spines or continuous along the whole flank forming a keel on the caudal peduncle. Most marine populations have complete series of plates (up to 37) while freshwater populations may have a complete series, only a few anterior plates, or both these extremes and intermediates. NCR fishes have a complete row of plates (although not as heavy as in marine fish) or there may be some absent before the caudal peduncle keel (the partial morph), and rarely are fish found with no keel and only anterior plates (Coad, 1985b). A population in a stream near Eardley was composed wholly of the partial morph, an unusual finding as the rare partial morph populations are usually found in lakes less than 10 km from the sea. Some fishes in the NCR show fusions of vertebrae, as revealed by x-rays (Coad, 1974). This anomaly may be due to adverse temperatures during development.
Colour
Marine populations are more silvery on the flanks than freshwater ones which are more olive. Generally the back is green-brown, olive or grey to blue-black, flanks olive to silvery and the belly silvery-white. Fins are generally clear. Breeding males develop a red belly and throat, blue sides and have bright blue eyes. Some populations in the Queen Charlotte Islands have lost or reduced red throat and belly colour which may be related to diets deficient in carotenoids.
Size
Attains 10.2 cm.
Distribution
Found on the Hudson Bay and southern Baffin Island coasts and nearby freshwaters and south on the Atlantic coast and nearby freshwaters to Chesapeake Bay. Also inland to the Ottawa River and Lake Ontario. Introduced to Hasse Lake, Alberta and to lakes Huron and Michigan and possibly Lake Superior; also introduced as bait fish to various localities in southern Ontario. On the Pacific coast and nearby freshwaters from the Bering Strait of Alaska to California including British Columbia. Also in Europe and western Asia from the Arctic south to Syria and in the western Pacific Ocean south to Korea. In the NCR, this species is more commonly encountered in Québec waters as, despite extensive and intensive sampling, there are few NCR Ontario records although these are confirmed by specimens in the Canadian Museum of Nature collections.
Origin
This species is a relict of the Champlain Sea episode, when the sea invaded the Ottawa Valley about 11,800 B.P. (Dymond, 1939; Dadswell in Coad and McAllister, 1975), having survived in an Atlantic coastal refugium. A fossil stickleback from Green's Creek was dated to about 10,000 years ago (McAllister et al., 1981; 1987).
Habitat
These sticklebacks inhabit lakes, ponds, rivers and streams. Marine and lake fish can be pelagic. Their preferred temperature is 9-12°C.
Age and Growth
Life span is a little over 3 years although some fish probably live only 1 year and a few months, dying after they spawn.
Food
Food is various crustaceans, aquatic and terrestrial insects, snails, worms, fish eggs and fry including their own species, and a wide variety of other available organisms taken both on the bottom or pelagically. Females feed mostly in the early morning at a marine site at Isle Verte, Québec. Females are important cannibals, forming raiding schools of up to 300 fish which overwhelm the nest-defending male. A male will divert the raiders by diving to the bottom and rooting in the mud away from his nest, as though feeding on the nest of another stickleback, by snout tapping on the bottom as though showing a nest to a female, or by swimming away high above the bottom on his side, silver flanks shimmering in the light, which leads the females away from his nest. A male may even pick up a dead stickleback or a discarded cigarette butt, bright underwater objects, and swim erratically away chased by the other sticklebacks which try to steal this attractive object. Some females known as courtship cannibals, not yet ready to spawn, mimic reproductive females and court males to gain access to eggs already in the nest on which they feed. Many fishes and birds, and even snakes, seals and small mammals, feed on sticklebacks despite their protective spines which are locked erect when they are disturbed. Spines and body plates are concentrated at the anterior end of the body and at the centre of mass. This is where most predators strike and even tail caught fish are manipulated so as to be swallowed head first incurring most injuries anteriorly. Loss of posterior plates may increase swimming ability and enable sticklebacks to escape predators where shelter is available or predators have similar swimming speed. Open waters and fast predators would encourage more plates.
Reproduction
Spawning occurs from April to October, varying with locality over the wide range of this species. NCR fish taken in June had eggs 1.2 mm in diameter indicating spawning in June-July (McAllister and Coad, 1975). The male parental cycle at Isle Verte lasts 9-15 days with female interspawning intervals of 19 days. Males and females only complete one spawning here though laboratory studies show males capable of 5 reproductive cycles and females of producing a clutch of eggs every 3-4 days. Harsh physical conditions are probably the cause. The male builds a barrel-shaped nest in shallow, sandy areas from plant fragments glued together on the bottom. The nest is in an open area but near vegetation. The nest has an opening at each end. The male has a complex courtship dance with zig-zag motions and a leading motion to the nest. A responsive female adopts a submissive head up position, which also reveals the egg-swollen belly. The male pokes his snout at the nest to indicate its position to the female, tipping his head sideways to display the bright red throat. The male jabs the female with his snout through the nest wall after she enters to stimulate egg release. He then follows the female through the nest to fertilise the eggs and drives the female away. Some males steal eggs from a rival male and some eggs in a nest are fertilised by a "sneaker" male. The parenthood of eggs in nests, which determines these observations, was confirmed by DNA "fingerprinting". In Crystal Lake, B.C. a female initiates courtship by "jumping" on the back of a male in open water, squirming and pressing against his erect dorsal spines. This courtship is not as conspicuous as zig-zag dancing and serves to avoid egg raids by large, bottom-feeding female schools. The male can search the surrounding water for raiders before leading the female down to his nest. Several females may spawn in one nest which can contain up to 1026, yellowish 1.8 mm diameter eggs. Some females at Isle Verte have up to 838 eggs on average. The male guards and fans the eggs and guards the fry. Females ofter cannibalise eggs and the stress of defending against female attacks shortens male life span. Many males do not construct nests and many which do are unable to attract females. Nest cover and aggression are probably important factors in male success.
Importance
This species occasionally appears in local newspaper reports and appears on information signboards at Pink Lake, Gatineau Park (Coad, 1985b). It is of considerable importance to scientists despite its small size and lack of direct economic importance. Threespine Sticklebacks have been studied extensively for the light they throw on speciation and evolution, and on fish behaviour. It helps that they are easily maintained and bred in aquaria.
One aspect of stickleback variation is the number of plates along the flank. The classical situation has been examined in the Little Campbell River, B.C. A fully-plated marine form enters freshwater to spawn in the river. There it encounters a low-plated freshwater form and hybrids with an intermediate plate count result in a narrow contact zone. Freshwater males zig-zag more, glue nests more and bite less than marine males. Reproductive behaviour also differs. The 2 forms act as good species. However low and fully-plated forms co-exist in lakes and appear to be a single species. A population near Eardley, Québec in the NCR is composed almost entirely of partially-plated fish, a rare occurrence, only the fourth in eastern North America where such populations are usually in lakes 10 km or less from the sea (Coad, 1983; 1985b). In the absence of parental forms (fully- and low-plated), the occurrence of a population comprised only of partially-plated fish shows that the classical situation does not always apply (Coad, 1985b). Most other NCR populations are comprised of fully-plated or a mix of fully- and partially-plated fish (sample sizes are small for some populations, making population description uncertain). In the NCR, it is surmised that the fully-plated marine populations, relicts of the Champlain Sea, have variously retained all or lost some of their plates - but the reasons are unknown. Perhaps environmental factors play a part.
The species is often referred to as the "Gasterosteus aculeatus complex" because the fishes included under the scientific name include some forms which act as good species but have not yet been adequately defined. Some of these unusual forms, believed to be good species are described as the Enos, giant and Texada sticklebacks. There is also a stickleback in Nova Scotia marine waters which has unique male breeding colours, the white stickleback. Other Pacific coast populations variously have reduced or absent pelvic skeletons, plates, and dorsal fin spines, black rather than red breeding colours or are unusually large. Benthic forms have large, deep bodies, wide mouths and few, short gill rakers while limnetic forms have the opposite characters - both forms are found in Paxton Lake on Texada Island, B.C. Other characters, such as vertebral counts, show as much variation between localities from one river system in the Queen Charlotte Islands as in all of Europe. Rapid speciation rates are common in these sticklebacks since the age of the lakes in which they live is about 9500 years. Local selection, related to predators in a fish poor environment and feeding environments, has resulted in a wide range of characters with a genetic basis. Unarmoured populations of the Threespine Stickleback, which may be a distinct species, are reported from lakes on Graham Island in the Queen Charlotte Islands, B.C. They were given "rare" status in 1983 by the Committee on the Status of Endangered Wildlife in Canada. All the unusual populations of threespines in British Columbia should be protected as simple alterations of habitat or introduction of another fish species may upset the delicate balance which has led to their evolution.
Fossils of Quaternary age (ca. 10,000 years ago) have been found in clay nodules from Green Creek in the NCR, relicts of the Champlain Sea (McAllister et al., 1981; Harington, 1972; 1983; McAllister et al., 1987).
Ninespine Stickleback / Épinoche à neuf épines
Pungitius pungitius (Linnaeus, 1758)
Taxonomy
Other common names include Tenspine Stickleback, Pinfish, Tiny Burnstickle, Many-spined Stickleback, Kakilahaq, Kakiva, Kakilasak, Kakidlautidlik, Kakilusuk and Kakilishek. The scientific name Pungitius occidentalis (Cuvier in Cuvier and Valenciennes, 1829) has been proposed for this species in eastern North America but has not been widely used (Haglund et al., 1992).
Key Characters
This species is characterised by 6-12 (usually 8-11) dorsal fin spines alternately leaning to the left and right, no obvious, large bony plates on the flank and colour.
Description
Bony plates are present but are small and often 0-8 in freshwater, along the whole flank and onto the caudal peduncle in the sea. The caudal peduncle is long and slender. Dorsal fin soft rays 8-13, anal fin with 1 spine and 6-11 soft rays, pectoral rays 10-11 and pelvic fin with 1 spine and 1 soft ray. The pelvic skeleton is absent in many fish from Wood Buffalo National Park, Alberta and many populations across Canada contain a few fish which have a reduced or absent pelvic skeleton but none are reported from the NCR. There are 11-14 slender gill rakers.
Colour
Overall colour is dark to light green, yellow-green, olive, brown or grey with dark bars, mottles and blotches on the flank and a silvery to yellowish-white belly. Fins are clear. Breeding males are overall jet black and have white to light blue pelvic fins. Fish from Lake Huron have a black ventral patch rather than being black overall.
Size
Reaches 9.0 cm.
Distribution
Found from all eastern Canada to northern and eastern Alberta, northeastern British Columbia, the Mackenzie valley and all the N.W.T., Baffin, Banks and Victoria islands. In the U.S.A. south to New Jersey on the Atlantic coast, in Great Lakes drainages and around coastal Alaska but not far south on the Pacific coast. Also across northern Eurasia and south to Japan and China.
Origin
This species entered the NCR from a Mississippian refugium as specimens from the Gatineau Valley conform to the Mississippian form as described by McPhail (1963)(Dadswell, 1972; 1974). Its salt-tolerance facilitated dispersal in the Champlain Sea and up the river valleys on the Québec side before sea level fell. McAllister and Coad (1975) recorded fish from Lac Heney, north of the NCR, as having mean values typical of a coastal marine form from the Bering Sea region (lateral plates = 3.67), of a freshwater form (dorsal spines = 9.04) and of an intermediate form (pectoral-pelvic ratio = 1.54, gill rakers = 12.67). NCR populations may have arose from a fusion from both refugia, the freshwater form via the Fossmill outlet of the Great Lakes and the coastal form via the Champlain Sea intrusion. Mandrak and Crossman (1992) suggest both the Beringian and Mississippian refugia are possible sources.
Habitat
Ninespines are found in both fresh and salt waters but usually enter fresh waters to spawn. In lakes it is found down to a maximum of 110 m and it is believed to overwinter in deep water, but it is commonest in shallow bays. It is also common in slow streams and ponds. It is especially abundant in lakes which have a lot of submerged vegetation. Their preferred temperature is 9-10 or 15-16°C, a bimodal distribution.
Age and Growth
Life span may be over 3 years and maturity is attained at 1 year for 90% of males but only 40% of females in Lake Superior. All are mature at age 3. In the Matamek River, Québec life span is 1 year and some months but in Matamek Lake over 2 years. In a tidal creek at Isle Verte, Québec, most fish appear to live about 1 year although some may survive to reach 2 years and some months.
Food
Food comprises aquatic and flying insects, crustaceans, molluscs, worms and eggs and larvae of their own and other fish species. Females feed mostly in the early morning at Isle Verte, Québec. Male diet is more diverse than other sticklebacks because they spend more time away from their nests. This stickleback is commonly eaten by sport fishes.
Reproduction
Spawning takes place in May to July. Individuals with large eggs and breeding colouration are found in Lac Heney, north of the NCR, in June. The male builds a nest off the bottom in dense vegetation, gluing plant fragments together with extruded kidney secretions. In areas without vegetation the nest is built on the bottom and even on turbulent, rocky lake shores. The male defends his nest territory by charges, nipping, biting and chasing. Other encounters involve a slow approach with pelvic spines erect and the head angled slightly down followed by a retreat or the two combatants circling rapidly biting each other's tail. Mouth fighting may also take place in the most energetic fights. Males may drag other males, sculpins or small suckers away by the dorsal or tail fins. The nest is a tunnel open at both ends and about 3-4 cm long. Nests are reported to be open at one end only in Lake Superior, the fish entering and turning around to deposit eggs or sperm. The male courts a female with a complex dance. He angles his body head down, an aggressive position, erecting his spines, twisting his body into a slight s-bend, and zig-zagging towards her. The female assumes a submissive, head up position and follows the male to the nest. The male indicates the nest entrance with his snout, the female pushes past to enter the nest and the male vibrates near her tail to stimulate egg deposition. Each female lays 20-80 eggs and is chased away by the male. He may mate with up to 7 females. Eggs are up to 1.5 mm in diameter and fecundity can reach 136 eggs at Isle Verte, Québec, a tidal creek, compared to only 71 eggs in the freshwater Matamek River system, Québec. Nests at Isle Verte had a mean number of 331 eggs or fry. The male swims through his nest without stopping, but fertilises the eggs. The eggs are fanned and so aerated by the male. A male may build a second nest while still guarding the first one. The young move away from the nest when about 2 weeks old but up till then he catches them in his mouth and spits them back into the nest.
Importance
This stickleback is food for other fishes despite its spines.
© Brian W. Coad (www.briancoad.com)