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SPECIES AT RISK – PAGE 11 In Canada, species are given one of five levels based on how much at risk they are. • Extinct [12 in Canada] Any species that no longer exists anywhere on earth. Great auk Labrador duck Banff long-nosed dace hunted hunted accidental 2. Extirpated [21 in Canada] Any species that no longer exists anywhere in Canada. Black-footed ferret Timber rattlesnake Frosted elfin eliminated food persecuted accidental 3. Endangered [141 in Canada] Any species close to extinction in all, or part, of Canada. Swift fox Eskimo curlew persecuted hunted Northern cricket frog accidental 4. Threatened [99 in Canada] Any species likely to become endangered, if things don’t change. Wood bison Least bittern Killer whale disease accidental pollution 5.Vulnerable (Special Concern) [142 in Canada] Any species that is at risk due to low or declining numbers. Grizzly bear Spotted turtle Peregrine falcon persecuted pet trade pollution FACTORS INFLUENCING STATUS a.Size Larger animals need: more food; more space. Both eat a similar diet, BUT one eats much more & so needs to move more to find more food b. Diet A carnivore is at greater risk because its food may become rare more readily than a herbivore’s food will become rare. Also, a specific diet is riskier than a general diet. The frog is at more risk than the shrew as it eats only crickets c. Biotic Potential Birth rate, survival to reproductive age, births per year and births per lifetime are all part of this. Mice breed much faster than buffalo. d. Range of Species An animal that has a small species range is at greater risk as something may happen to that range.. The species at left has a smaller range and so is at a greater risk. e. Range - Individual A larger individual range puts the species at greater risk as they roam to find food, mate, etc. f. Human Interactions Some animals do well around people and some do not. Killed from fear; by cars. Some avoid humans; Some are poisoned. FOLLOW-UP ASSIGNMENT Now lets try to put some of this knowledge into practice. turn to chart on next page size diet biotic potential A B small small C large herbivore carnivore carnivore D E F small large large omnivore herbivore omnivore high low high high low low range -species large small large small small large rangeindividual small large large small large small many few many few many few human interactions negative traits; A –1; B – 4; C – 4; D – 1 ½ ; E – 5; F – 2 ½