Extinct and Extirpated Species
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H WILDLIFE IN BRITIS COLUMBIAAT RISK Extinct and Extirpated Species At least species and subspecies have disappeared from British Columbia in historic times. Ministry of Environment, Lands and Parks some invertebrate groups. The CDC lists activity led to their demise, before biol- 14 species or subspecies (referred to col- ogists even had a chance to give them lectively as “taxa”) that are extirpated proper scientific names. from British Columbia and 5 that are Whitefishes are found across north- Extinct and Extirpated extinct. The real numbers are undoubted- ern Canada. From the time that the last Species in British Columbia ly higher, since we are far from having major glaciation ended, about 10 000 lthough British Columbia has a identified every plant and animal species years ago, they have been expanding more varied flora and fauna than in the province. Of the estimated 35 000 into new, under-utilized habitats and any other province in Canada, species of insects that live in British evolving into new forms. For scientists Awe should not take this rich biodi- Columbia, for example, only about half who study evolution, these fishes offer versity for granted. Many species and are known to science. With this many a rare opportunity to analyze the subspecies are at risk. Worse yet, some unknown species, it is inevitable that process of speciation (the evolution of have been extirpated from British some have been lost before we even rec- new species) in progress. The Dragon Columbia (they are no longer found ognized their existence and that these Lake Whitefish (Coregonus sp 1), within the province, but still live else- unrecorded extinctions and extirpations which lived in Dragon Lake near where) or have become extinct (they no will continue to happen. Quesnel, was eradicated in 1956 when longer exist anywhere in the world). In addition to the 19 extirpated and the lake was poisoned to remove When a province has nearly 500 extinct taxa, 37 others are listed by the unwanted fishes before introducing species of birds and more than 3000 CDC as being “historic” (see table). trout for sport fishing. plant species, the loss of one or two of This qualifier is applied to species Two fishes that once lived on Las- these may not seem that serious, queti Island in the Strait of Georgia – but there are a number of reasons “The outstanding scientific discovery of the Hadley Lake Limnetic Stickleback why every species and subspecies is the twentieth century is not television, or (Gasterosteus sp 12) and the Hadley worthy of conservation. For some radio, but rather the complexity of the Lake Benthic Stickleback (Gasterosteus people, the most important consid- land organism. Only those who know the sp 13) – were also examples of rela- eration is the known and potential tively young species that had the most about it can appreciate how little is economic values of plants and ani- potential to increase our understand- known about it. The last word in mals, which provide us with build- ing of the evolutionary process. The ing materials, medicine, food, pest ignorance is the man who says of an two Hadley Lake sticklebacks were control, and much more. For oth- animal or plant: “What good is it?” If the what is known as a “species pair” – ers, it is the aesthetic or spiritual land mechanism as a whole is good, then two distinct but closely related species significance of living beings. In every part is good, whether we understand living side-by-side in the same small addition to these values, ecosys- it or not. If the biota, in the course of aeons, lake. They were lost in the early 1990s tems are complex networks of has built something we like but do not when non-native catfish, which prey interconnected organisms and the understand, then who but a fool would on stickleback eggs, were introduced loss of any one component of an discard seemingly useless parts? To keep to their home waters. ecosystem can affect all the remain- every cog and wheel is the first British Columbia’s fourth extinct ing species, often in ways we do animal is the Dawson Caribou precaution of intelligent tinkering.” not yet understand. Furthermore, (Rangifer tarandus dawsoni). These , certain types of organisms, such as , . elusive caribou lived in muskeg habi- lichens, amphibians, and fish, are tat on the Queen Charlotte Islands. valuable bioindicators – the health of whose presence in British Columbia Early scientific records of their pres- these species provides us with tangible has not been verified for a long time – ence on Graham Island were based on evidence about the health of the ecosys- generally about 45 years – but for which a few accounts by Haidas who lived tems in which they live. there is a reasonable expectation that there, and the discovery of tracks and someday they may be found again. antlers in the late 1800s and early British Columbia’s 1900s. The last Dawson Caribou ever casualty list Status: Extinct to be reported was seen in 1908. he BC Conservation Data Centre hree of the five British Columbia The cause of this subspecies’ extinc- (CDC) maintains records on animal species that have become extinct tion is a mystery. Over-hunting is and vascular plant species at risk in are fish. Each one was confined to one possibility, although any hunting Tthe province, as well as mosses and Ta single lake. In each case, human that was done by the Haida or by Europeans is completely undocument- Columbia are all at the northern edge in the steppe and lower montane zones ed. Black-tailed Deer, which have of their geographic ranges. as far south as California. now dramatically changed the vegeta- Pink Sandverbena (Abronia umbel- tion on Graham Island, were not pre- lata ssp acutalata) (on cover) grows Insects sent until government officials intro- on coastal beaches and sand dunes. The two British Columbia insect duced them in 1900 and they did not The only locations where it has been species that are known to have been start having a significant impact for found in British Columbia are extirpated are both butterflies. some years after that. Ahousat and Pachena Bay It is probable that other, less showy The fifth extinct species is on the west coast of insects have also been lost from the Passenger Pigeon, which Vancouver Island. It the provincial fauna without ever once existed in huge num- has not been collected having been identified. bers across North America. in this province since Until very recently, biologists thought We don’t know how com- 1927, despite extensive that an unnamed subspecies of the mon these birds were in searching. It is also Large Marble (Euchloe ausonides ssp 1, B.C, but there are records believed to be extir- the Island Large Marble) was extinct. from the Fraser Valley pated from Washing- Its known world distribution was from and the Peace River. The ton, but is still found at the Greater Victoria area, Wellington, last Passenger Pigeon died in the southern end of its and Gabriola Island. Despite intensive captivity in the U.S. in 1914. range, in Oregon. searching, this subspecies had not been Another former Vancou- seen since 1908. The discovery of two Status: Extirpated : ver Island species populations of butterflies that are Plants is Lobb’s Water-but- believed to be this same subspecies Four moss species and four flowering tercup (Ranunculus on San Juan Island, Washington, plants are considered extirpated. lobbii), which grew in seasonal pools changes its status from extinct to extir- Two of the extirpated mosses, Micro- and wet sites, from the southern tip of pated. The reasons for this butterfly’s mitrium tenerum and Pseudephemerum Vancouver Island south to California. disappearance from its Canadian range nitidum, have not been found any- Within British Columbia it was found are not known, but suspected causes where else in Canada. Each of these only in the Victoria area and has not include high levels of cattle and sheep very tiny mosses was known only been recorded since 1948. Urban devel- grazing and non-native parasites asso- from a few sites in the Vancouver opment was most likely the major ciated with the introduced Cabbage area, all of which have been destroyed cause of its disappearance. White butterfly. by human activity. The range of Common Downingia The Viceroy (Limenitis archippus), The habitat of the extirpated moss (Downingia elegans) extends from a widely distributed North American Discelium nudum is naturally ephemer- southeastern British Columbia, south species, was recorded in British al – the open earth banks where it to Nevada and northern California. grows are subject to slumping or Restricted to wet meadows and ponds invasion by seed plants, which crowd in the steppe and lower montane it out. In the past, researchers found zones, it has been found at only one this species in the Vancouver area and site in this province – on the muddy in the Queen Charlotte Islands, but shores of Leach Lake near Creston. all known British Columbia popula- When the shoreline of this lake was tions have now been eliminated. It permanently altered by a waterfowl is still found in other parts of North enhancement project all provincial America. representatives of this species were The moss Physcomitrium immer- eliminated. : sum is known from museum speci- The only location where Rabbit- Chris Guppy photo mens collected from margins of culti- brush Goldenweed (Ericameria Columbia’s southern interior from vated and fallow fields in the Fraser bloomeri) has been found in British 1913 to 1920, and was last collected Valley. It is also still found in other Columbia is near Westbridge in the at Lillooet in 1930.