Amaz­ing Grass

More than 70 per cent of Canada’s na­tive prairie grass­lands has been lost to agri­cul­ture and devel­op­ment, en­dan­ger­ing this pre­cious ecosys­tem and the many species it en­com­passes. It will take ev­ery­one — ranch­ers, In­dige­nous peo­ple, con­ser­va­tion­ists and th

Canadian Wildlife - - NEWS - By Niki Wil­son

More than 70 per cent of Canada’s na­tive prairie grass­lands has been lost to agri­cul­ture and devel­op­ment, en­dan­ger­ing this pre­cious ecosys­tem and the many species it en­com­passes. It will take ev­ery­one — ranch­ers, In­dige­nous peo­ple, con­ser­va­tion­ists and three lev­els of gov­ern­ment — to con­serve this pre­cious nat­u­ral her­itage. Plus: Five grass­lands species that need pro­tec­tion now!

ONE OF TREVOR HER­RIOT’S EAR­LI­EST MEM­O­RIES IS OF walk­ing through tall grass, hand in hand with his fa­ther. It was late sum­mer, and they were headed to lo­cal fair­grounds in the eastern part of the Qu’ap­pelle Val­ley near the vil­lage of Tan­tallon, Saskatchewan. The grass stretched above his head, but as it moved, it al­lowed him to steal glances of the dis­tant hills he says lay like sleep­ing an­i­mals. “It’s the type of grass­land I re­ally im­printed on,” says Her­riot, now an ac­claimed au­thor, nat­u­ral­ist and activist in prairie grass­land con­ser­va­tion. “I had a strong sense of the world be­ing be­nign and safe.”

In his memory, he and his fa­ther emerged from the grass to a vi­brant fair. Pies, toma­toes, petu­nias and marigolds were care­fully ar­ranged be­fore him with “a sense of pride in pro­duce that comes when you’ve grown it with your own hands.”

That was around 1962, and by then hard­work­ing im­mi­grants had es­tab­lished the ranches and farms that formed the base of the bread belt of Canada. But this came at the cost of most na­tive grass­land prairie, lost to the plow in an ef­fort to feed a grow­ing na­tion. By the time Her­riot walked to the fair, roughly two-thirds of these grass­lands had been turned over in Al­berta, Saskatchewan and Man­i­toba. Many of the species that were con­sid­ered in­com­pat­i­ble with agri­cul­ture, like the swift fox and black-footed fer­ret, were ei­ther erad­i­cated or close to it.

What re­mains of these grass­lands is now scat­tered in frag­ments across the Prairie prov­inces and is slowly be­ing con­verted to crops or other hu­man uses. Ex­cep­tions can be found in a few pro­tected ar­eas, on pri­vate ranch lands and on com­mu­nity pas­tures. Com­mu­nity pas­tures hold some of the great­est con­ser­va­tion po­ten­tial, but that may change if the Prairie prov­inces, hav­ing newly ac­quired re­spon­si­bil­ity for their man­age­ment in 2012, don’t sup­port a strong con­ser­va­tion man­date.

At stake are the al­ready dwin­dling num­bers of grass­land birds, pronghorn, small mam­mals, in­sects and rep­tiles that evolved to live only in this north­ern reach of North Amer­ica’s once vast tem­per­ate grass­land. Sav­ing what re­mains of these en­dan­gered species and land­scapes may rely on the abil­ity of Cana­di­ans to sup­port the ranch­ers, com­mu­ni­ties and con­ser­va­tion­ists strug­gling to hold on to what is left.

Be­fore Euro­pean set­tle­ment, the great tem­per­ate grass­lands of North Amer­ica stretched unim­peded from north­ern Mex­ico to the Prairie prov­inces of Canada. Grasses dom­i­nated, fill­ing a niche where it was nei­ther wet enough for trees nor dry enough for desert. Plains bi­son roamed in herds mil­lions strong, their thun­der­ous pres­ence carv­ing habi­tat in the land­scape for a mul­ti­tude of species in­clud­ing badgers, pronghorn and prairie dogs. Great Plains wolves and the prairie pop­u­la­tion of griz­zly bears dom­i­nated the top of the food chain, along with the bi­son-hunt­ing peo­ple who used fire to help main­tain the ecosys­tem. The calls of Sprague’s pip­its and ch­est­nut-col­lared longspurs sig­nalled the start of spring, while great mi­grants like snow geese stopped in droves to rest and re­fuel at abun­dant wet­lands and prairie pot­holes on their way to their Arc­tic breed­ing grounds.

By the mid to late 1800s, the bi­son were all but gone, re­mov­ing one of the most crit­i­cal forces that shaped the Prairies. The first peo­ple who hunted them were beaten back, and many were forced onto reser­va­tions. Con­versely, the promised free­dom and land own­er­ship lured Euro­pean im­mi­grants to the Prairies, where they tilled the soil to grow crops. As agri­cul­ture took hold and towns and cities grew, there was less room for the swift fox, black-footed fer­ret, Great Plains wolf and the prairie pop­u­la­tion of griz­zly bears that were even­tu­ally hunted, poi­soned or pushed out. More than two-thirds of what was once a con­tigu­ous stretch of the Prairie Eco­zone that spanned over 465,000 square kilo­me­tres of the Prairie prov­inces — al­most 5 per cent of Canada’s land­mass — was lost for­ever.

“Wild prairie is now one of the most en­dan­gered ter­res­trial ecosys­tems,” says Carolyn Cal­laghan, con­ser­va­tion bi­ol­o­gist for the Cana­dian Wildlife Fed­er­a­tion. “A bro­ken prairie is never the same.” She likens the prairie to an ice­berg. “Much of the liv­ing sys­tem is be­low the sur­face — the grass is only a small por­tion of what is re­ally there.” When it is turned over, the lichens, mi­crobes, plants and other mem­bers of the soil com­mu­nity are ir­re­vo­ca­bly al­tered, which is why she says “Ev­ery scrap of na­tive prairie grass­land left is pre­cious. We need to keep what we have.”

Prairie ecosys­tems are not just homes for an­i­mals; they also pro­vide im­por­tant ser­vices for the peo­ple who live there, says Dan Kraus, con­ser­va­tion bi­ol­o­gist with Na­ture Con­ser­vancy of Canada. The un­der­ground root sys­tems of grass­lands re­tain mois­ture in the land and help hold back flood­wa­ters in a way tilled soil can­not. They also re­lease mois­ture dur­ing drought. Na­tive prairies store more car­bon than they pro­duce, and Kraus points out they may prove to be more re­sis­tant to fu­ture drought and the sub­se­quent ero­sion that will likely be ex­ac­er­bated by cli­mate change.

The Prairie Eco­zone is di­vided up into sev­eral types of grass­lands, all of which have suf­fered mas­sive range con­trac­tions. In 2010, ac­cord­ing to the Cana­dian Bio­di­ver­sity: Ecosys­tem Sta­tus and Trends Re­port of the Cana­dian Coun­cils of Re­source Min­is­ters, only 25 per cent (about 10,000 sq. km) of mixed and fes­cue prairie were left in the Prairies eco­zone. Tall­grass prairie had all but dis­ap­peared, with only 100 sq. km left of its for­mer 6,000 sq. km in Man­i­toba. Since then, grass­lands con­tinue to suc­cumb to crop con­ver­sion and ur­ban ex­pan­sion, and we may be los­ing even more than we think.

Ni­cola Koper is a pro­fes­sor at the Nat­u­ral Re­sources In­sti­tute at the Univer­sity of Man­i­toba who has been study­ing prairie ecosys­tems for 18 years. A lot of her work has fo­cused on grass­land bird com­mu­ni­ties. She says it’s not just the con­ver­sa­tion of grass­lands to other uses, but the ad­di­tional loss to “edge ef­fect” that is hav­ing a tremen­dous im­pact on grass­land birds. “This re­sults in a much higher loss of suit­able habi­tat across the land­scape than we as hu­mans re­al­ize when we con­vert these ar­eas.” “Edge” is cre­ated any time na­tive prairie grass­land comes up against al­tered habi­tat, like hu­man in­fra­struc­ture and crop­land. Edge ef­fects are cre­ated from things like recre­ational ac­tiv­i­ties, roads or crop­land. Oil wells bring noise and roads. Some­times, things that seem be­nign can have an ef­fect, Koper says. For ex­am­ple, fences around crop­lands cre­ate perches for rap­tors and cow­birds where there were none be­fore. All of these things change the land­scape for grass­land birds, she says “and un­for­tu­nately, in many cases it makes it a lot less suit­able for them.”

Com­pli­cat­ing mat­ters is the fact that, like all ecosys­tems, the prairies are not a mono­cul­ture, but a di­verse patch­work of sub­tly dif­fer­ent habi­tats. Many species are spe­cial­ists in a par­tic­u­lar type of grass­land. What’s good for one is not nec­es­sar­ily good for an­other.

“The species that like mod­er­ate veg­e­ta­tion are do­ing pretty well in Canada,” says Koper. Moder­ately grazed grasses are well main­tained by ranch­ers, who have been

WHEN CANA­DI­ANS THINK ABOUT GLOB­ALLY RARE ECOSYS­TEMS, THEY THINK ABOUT RAIN­FORESTS AND CORAL REEFS. BUT IN THE HEART­LAND OF CANADA IS AN ECOSYS­TEM THAT IS AS IM­POR­TANT, RARE AND EN­DAN­GERED AS ANY ON THE PLANET

suc­cess­ful in avoid­ing ero­sion in this way, she says. “But those species that like lightly grazed or undis­turbed habi­tat are de­clin­ing.” The Sprague’s pipit is one of those birds, pre­fer­ring to stay hid­den in tall grasses. Listed as threat­ened un­der Canada’s Species at Risk Act, like many grass­land spe­cial­ists its pop­u­la­tion has de­clined sig­nif­i­cantly over the past four to five decades, says Koper.

Con­versely, there are also de­clines in species that like heav­ily grazed pas­tures, like the ch­est­nut-col­lared longspur, also a threat­ened species. These birds evolved to take ad­van­tage of the way bi­son grazed, and “bi­son re­ally ham­mered some ar­eas,” says Koper. “Birds that re­ally adapted to that en­vi­ron­ment are now los­ing their habi­tat.”

By bet­ter mim­ick­ing the way bi­son used the land­scape, con­ser­va­tion­ists and ranch­ers can work to­gether to pro­tect na­tive grass­land prairie. It’s a re­silient sys­tem, Koper says. “Even if one area is re­ally heav­ily grazed, once you re­move the live­stock, the habi­tat comes back pretty much the way it was be­fore.”

To that end, the big­gest pas­tures are the best, Koper says. Cat­tle choose where they graze more sim­i­larly to the way bi­son did. Some ar­eas are heav­ily grazed, while oth­ers are not grazed at all. High in­ten­sity over short du­ra­tions, with long rest pe­ri­ods to fol­low, is key.

COLOURS OF THE LAND (Left) A lichen-cov­ered rock, 70 Mile Butte in the dis­tance. (Right) Pronghorn (An­tilo­capra amer­i­cana) which are re­lated to gi­raffe

GRASS­LANDS AT RISK RISK • South­west Man­i­toba Up­lands • Cy­press Up­land • Fes­cue Grass­land • Lake Man­i­toba Plain • Aspen Park­land • Mixed Grass­land • Moist Mixed Grass­land • Aspen Park­land

MORN­ING HAS BRO­KEN... Sun­rise over the French­man River Val­ley in Grass­lands Na­tional Park in south­ern Saskatchewan

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