Lake Cisco (Coregonus artedi)
Illustration: Ellen Edmonson and Hugh Chrisp (Wikimedia Commons)
Ontario's far north, that area above an imaginary line running from Woodland Caribou Provincial Park in the west to Natogami Lake in the east, comprises 42% of the province. At 451,920 square kilometres, that's a huge area. It's bigger than the UK. It's bigger than Romania. It's bigger than all three maritime provinces combined. Big, but easy to overlook if you're not one of the 0.2% of Ontarians who live there, or one of the lucky southerners who has visited this intractable miasma of forest, muskeg and tundra. Most southerners never give a moment's thought to the province's far north, nor its 1210 km of saltwater coastline. But there it sits, in all its subarctic glory, even if it is more or less forgotten by the vast majority of Ontarians.
If you've lived, worked or played in Ontario's far north, you know that in reality it's anything but forgettable. It's vast, and wild. It's a place where wildfires are often allowed to rage unchecked, where the forces of nature rule. Roads are few and mostly winter access only. Settlements are small, scattered and have only limited access to outside resources. In the dead of winter the forests are eerily silent and temperatures can be devastatingly cold. In summer the land bursts with life, which would be paradisaical if it weren't for the uncounted hordes of biting flies. Wildlife abounds, but given the immensity of the landscape, can be difficult to find. In the far north, the rest of the world seems very far away.
I've been lucky enough to enjoy two visits in recent years: once to the vast and sweeping tundra-treeline ecotone of Hudson Bay's Polar Bear Provincial Park; and once to the coastal wetlands, forested ridges and tidal flats of southern James Bay. But even after two visits chasing Nelson's Sparrows (Ammodramus nelsoni), Yellow Rails (Coturnicops noveboracensis), Northern Fulmars (Fulmarus glacialis), Smith's Longspurs (Calcarius pictus), Polar Bears (Ursus maritimus), Arctic Foxes (Vulpes lagopus), Caribou (Rangifer tarandus), Melissa Arctics (Oeneis melissa), Azure Darners (Aeshna septentrionalis), 'Hudson Bay' American Toads (Anaxyrus americanus copei) and dozens of other unusual (for Ontario) species, I've come to realize that there's one aspect of the far north's natural history that I still have almost no knowledge of: the marine fishes.
Ontario's Hudson Bay coast is home to very few people and is visited by fewer still. Cree hunters built these cairns in Polar Bear Provincial Park. Ice still lingers offshore in this June photograph.
Photo: Mark Conboy
Ontario's saltwater coast represents the southernmost extension of Hudson and James Bays, which together form the largest discrete body of water on Earth that completely freezes in winter and completely thaws in summer; ice cover lasts from December to May or June. As in any northern waters, ice plays a significant role in the lives of fish.
Marine fish live in a supercooled world, a world of liquid ice, in a sense. That's because saltwater has a freezing point of roughly -1.9 degrees Celsius. But that's an extremely challenging environment for fish to live in, requiring a whole suite of enzymes and other molecules that can function below the temperatures experienced by organisms in more benign environments. Furthermore, fish have a freezing point which is slightly above that of seawater. As a result, fish that are living in seawater could actually freeze solid before the water that surrounds them does. Some species get around this problem by migrating to deeper waters where ice doesn't form, owing to increased water pressure. A descent below 30 metres depth is usually sufficient to avoid freezing.
Other fish remain near the surface and have developed another strategy to avoid freezing: antifreeze proteins. Antifreeze proteins bind to rudimentary ice crystals, essentially coating them, and inhibiting further growth of those crystals. There are at least half a dozen known antifreeze proteins at work in arctic and antarctic fish. Because the proteins inhibit the growth of ice crystals, fish can live in shallow supercooled environments without the risk of turning into fishcicles.
Rivers such as Ontario's Winisk, Severn, Attawapiskat, Albany, and Moose are just as influential as ice is in determining the region's ecology. The estimated 750 cubic kilometres of freshwater that these and other rivers in Manitoba, Nunavut and Quebec pour into the bays annually, drastically lowers salinity levels across this relatively small oceanic basin. Consequently, fish diversity in the bays is a mixture of truly marine species and normally freshwater species that can live in the much reduced salinity.
Rivers bring such a tremendous amount of freshwater into the bays that one Canadian engineer has devised the Great Recycling and Northern Development Canal, an ill-conceived megaproject that calls for the construction of a dam across the mouth of James Bay to keep saltwater out, while allowing the ample inflow from rivers to eventually turn the bay into a massive freshwater lake. A canal would then be constructed to carry water south into the Great Lakes where it would be used to bolster water supplies in other parts of the continent. Such a scheme would irrevocably affect the region's ecology and would be an environmental disaster of nearly unparalleled proportions, but the fact that such a project would even be conceived of serves to underscore just how much freshwater enters the bays every year.
There are perhaps as many as 61 fish species in the bays, with about 53 of those known from southeastern Hudson Bay and James Bay; about half of them are strictly marine, while the rest are amadromous, spending at least part of their lives in freshwater or brackish estuaries. How many species regularly occur off Ontario's coast is a little unclear, but there are at least 20.
Indeed, when it comes to Ontario's saltwater coast, there is a lot that remains unclear. Relatively little is known about fishes in our forgotten north, because research has been rather limited. That's not to say that no research has been conducted. Early twentieth century expeditions were sent to Hudson Bay to determine any potential for establishing commercial fisheries there. No such potential was found. Even today, when it seems humans have managed to exploit virtually every corner of the Earth, there is still no true marine fishery in the bays. A small amount of commercial fishing, mainly limited to Arctic Char (Salvelinus alpinus) occurs along the Nunavut and Nunavik (northern Quebec) coasts. These harvests are relatively small, more akin to subsistence fisheries than full-scale commercial harvests, and are confined to rivers, not the bays themselves. The lack of a commercial fishery in the bays is probably one of the major reasons for the research deficit. But one area where there has been particular research interest is in understanding the impacts of hydroelectric development on amadromous species, particularly on the Quebec side of James Bay.
We do have a good understanding of which species are most common and widespread and which species are of prime ecological importance. Of the truly marine species, Arctic Cod (Arctogadus glacialis), Capelin (Mallotus villosus) and Pacific Sand Lance (Ammodytes hexapterus) are among the most significant. Arctic Cod have long been a food source for people living on the Belcher Islands off the coast of Quebec (the Belcher Islands are actually part of Nunavut, and so are all other islands in Hudson and James Bays), but have apparently never represented a significant subsistence fishery off the Ontario coast. Another cod, the similar but non-gregarious Greenland Cod (Gadus ogac) occurs in eastern James Bay but, interestingly, seems to be more or less absent from the Ontario coast. Belcher Islanders have also traditionally harvested Capelin where they spawn off shallow beaches, but again this species has never been harvested in significant quantities off the Ontario coast. Pacific Sand Lance have the curious behaviour of burying themselves in the benthos where they can even survive above the low tide line. Arctic Cod, Capelin and Pacific Sand Lance all school in large numbers and are the ecological cornerstones of Canada's arctic and subarctic marine environments, representing a significant food source for other fish, mammals and seabirds. Their importance off the Ontario coast is probably similar to elsewhere in the bays, but the extent to which that has been studied seems to be very limited.
Twohorn Sculpin (Icelus bicornis), Fourhorn Sculpin (Myoxocephalus quadricornis), Arctic Sculpin (Myoxocephalus scorpioides), and Shorthorn Sculpin (Myoxocephalus scorpius) are also marine inhabitants of Ontario's coast. Interestingly, there is a documented case of a young male Polar Bear (Ursus maritimus) diving for and catching Fourhorn Sculpin and Arctic Charr, making those the only two species the only fish for which Polar Bears have actually been documented to hunt; they normally focus on seals.
The Arctic Alligatorfish (Aspidophoroides olrikii) sounds formidable in name but only ever reaches a maximum length of 10 cm and feeds on tiny prey such as amphipods and ostracods. The woefully named Lumpfish (Cyclopterus lumpus) was long thought to be a primarily benthic species, with its suction cup-like pelvic fin and lack of swim bladder, but in reality it also seems to spend a great deal of time in the water column. Lumpfish, at one time were part of a fishery in Newfoundland and Labrador, where considerable numbers were taken for their nutritious row. The species has declined considerably in eastern Canada and is not fished as heavily anymore. Although it is fished in Greenland, it has never become a commercial species in Hudson or James Bays. Similar to the Lumpfish is the Leatherfin Lumsucker (Eumicrotremus derjugini). The lumpsucker is a true bottom-dweller, and it too is without a swim bladder but has a suction cup-like pelvic fin for anchoring to the bottom as an adult and to seaweed mats or other drifting debris as a juvenile. There's also the relatively little known, but widespread Variegated Snailfish (Liparis gibbus) and the Fourline Snakeblenny (Eumesogrammus praecisus). No sharks penetrate into southern Hudson Bay or James Bay, only the Greenland Shark (Somniosus microcephalus) reaches the northern parts of Hudson Bay and the deeper waters of the Hudson Strait.
A juvenile Lumpfish (Cyclopterus lumpus) using its suction cup-like pelvic fin to adhere to a piece of seaweed.
Photo: Hans Hillewaert (Wikimedia Commons)
The list of truly marine species is relatively short. But marine fish are only part of the piscean picture. In James Bay in particular, anadromous freshwater species form a significant portion of the diversity. Anadromous species spend at least part of their life cycle in freshwater, usually rivers, and part of their life at sea (or in large lakes, such as with many Great Lakes species). Lake Cisco (Coregonus artedi), Lake Whitefish (Coregonus clupeaformis), Round Whitefish (Prosopium cylindraceum) and Longnose Sucker (Catostomus catostomus) are commonly found in James Bay for at least part of their life cycles. Burbot (Lota lota) and Lake Trout (Salvelinus namaycush) are less common. Seldom do any of these species use saltwater in most other parts of their range. But in James Bay, the low salinity levels from river inflows means that these normally freshwater fish can survive. But all of these species become rarer in Hudson Bay, where salinity increases to intolerable levels.
Among anglers, perhaps the most notable of Ontario's northern amadromous fish is Brook Trout (Salvelinus fontinalis). Not normally thought of as an ocean fish, but rather one of streams, rivers and cold lakes, there are some populations that are amadromous (in the maritime provinces they're called salters). Both the typical permanently freshwater form and the amadromous form can be found in Ontario's Hudson Bay Lowlands, but of course, its only the salters that reach the bays themselves. These trout spend the first 2-4 years of their life in freshwater, before going to sea for 2-4 months, and then returning to freshwater to spawn. While at sea, Ontario salters lose their bright red colours, becoming silvery. Their vibrant colours return once they retreat to freshwater. The related Arctic Char also has permanently freshwater and anadromous forms throughout much of its range, though only the anadromous form is thought to occur in Ontario, and then only rarely.
Other freshwater species are found in James Bay from time to time, including Walleye (Sander vitreus), White Sucker (Catostomus commersonii), Slimy Sculpin (Cottus cognatus), Spoonhead Sculpin (Cottus ricei), Brook Stickleback (Culaea inconstans), Threespine Stickleback (Gasterosteus aculeatus), and Ninespine Stickleback (Pungitius pungitius). The latter two species are confined primarily to estuaries where the concentration of saltwater is lower still.
Unfortunately Hudson and James Bays have not been spared the scourge of introduced species. In a somewhat misguided attempt to artificially establish commercial and recreational salmonid fisheries, the eggs and fingerlings of Pink (Oncorhynchus gorbuscha) and Chum Salmon (Oncorhynchus keta) were introduced into several rivers in southern Hudson Bay and James Bay in 1955-56. Luckily none of the fish survived to found breeding populations. Another introduction to Hudson Bay has been the Rainbow Smelt (Osmerus mordax). Introduced for some confounded reason into river systems in northwestern Ontario, this species has spread into Manitoba and southern Hudson Bay. Rainbow Smelt are anadromous and gregarious. They consume the same planktonic and invertebrate prey as many native species, resulting in direct resource competition. Smelt themselves become prey for a multitude of other larger predatory species but many fishers claim that commercial and sport fish that feed on smelt spoil more quickly and taste poorly. Rainbow Smelt are not harvested in Hudson Bay or its tributaries, as they are in Atlantic Canada and on the Great Lakes.
There's still a great deal to learn about the fish of Ontario's saltwater coast. Perhaps the ever growing interest in arctic and subarctic ecosystems and the challenges they face from climate change will stimulate new research initiatives in our forgotten north. Until then, the vast northern coastline will remain as wild and elusive as ever.
