Prairies provide cryptic, undervalued, and threatened biodiversity

We are excited to welcome Lysandra Pyle to the blog today. Lysandra is an Ecologist from the University of Alberta and today she tells us about her fieldwork in the prairies. For more about Lysandra, see the end of this post!

My first memories of prairies are engrained in the experiences of my childhood growing up in south eastern Saskatchewan. Checking for ticks (Dermacentor variabilis), picking sharp seeds (Hesperostipa spp.) or spines (Opuntia spp.) out of skin, and waiting for my mom to forage every last Saskatoon (Amelanchier alnifolia) or choke cherry (Prunus virginiana) from a bush along a grid road were common summer activities. I remember sitting by a pond, home to painted turtles (Chrysemys picta), on a farm in the bald prairie south of Radville, SK and feeling the barometric pressure drop, warning of significant thunderstorm which rolled powerfully over the hills.

Saskatoons on the left and choke cherries on the right! Provides forage for coyotes, birds, and graduate students.

However the first time I was truly awakened to the wonder of this environment was during my first fieldwork experience. Thanks to the serendipitous luck of my university’s match-making internship program and the first choice candidate not having a driver’s licence, I moved to south western Saskatchewan for a summer term, working in a small rangeland plant ecology program. There I was bitten by the botany bug, as I gained hands-on experience working with native prairie plants and exposure to species at risk. That summer I purchased numerous field guides, started teaching myself plant identification, and enriched my native prairie immersion by frequently visiting Grasslands National Park and Saskatchewan Landing. Shadowing my supervisors as they effortlessly identified all of the plants in a quadrat and pulled back grass leaves to reveal unique ligules and collars had me hooked. Perhaps I was impressionable, but learning grasslands were so diverse changed me, provided me with a profound appreciation for where I am from, and gave me purpose.

This is the ecosystem I love and study. You can easily identify needle and threadgrass with curly awns (Hesperostipa comata) which is common in Mixedgrass Prairie. Its fruit has evolved to burrow into fur and skin!

Native prairie provides invaluable ecological services and irreplaceable habitat for wildlife. For my M.Sc. research I was transplanted into north central Alberta’s Aspen Parkland in January.  I spent that winter and spring anxiously waiting to explore northern fescue prairie. That summer I was tasked with driving around the peri-urban area of Edmonton, AB to interview landowners about their pasture management, score the health of their pasture, survey their plant communities, and sample the seed bank. Imposing my experience from SW SK, I planned to run a survey transect that was just over 1 km long. What I found was a landscape heavily modified by cultivation and fire suppression which caused woody encroachment (invasion by a clonal trees like aspen (Populus tremuloides)); the land was also subdivided into many smaller mixed farms which called for the reduction of the transect length (to 265 m) and a lowering of my expectations regarding the discovery of intact native pastures.  Historically, grasslands in the Parkland were dominated by plains rough fescue (Festuca hallii); currently, ecologists struggle to restore this grass, and these ecosystems are in my opinion endangered. Luckily I found an ecosite with relatively saline soil (which deterred cultivation) dominated by fescue.  This patch less than 260 ha was bustling with the biodiversity I commonly associated with southern grasslands. Less than 50 km from Edmonton, I heard the ‘UFO’ call of a Sprague’s pipit (Anthus spragueii, listed as threatened) and the Spring-of-the-gurgling associated with the western meadowlark (Sturnella neglecta).  This tiny patch of prairie was an oasis in a sea of wheat and canola. This illustrates the importance of preserving intact, native grasslands for obligate wildlife, and demonstrates that grassland is not simple, leafy, indistinguishable phytomass but has irreplaceable structure and heterogeneity which provides habitat.

Plains rough fescue (Festuca hallii) flowers irregularly; this was impressive for mid-May!

While surveying plant communities in vast open grasslands, I frequently pause for about 10 to 15 minutes to record plant community characteristics from my quadrat. In these moments, you can see over great distances – which is ideal for observing prairie wildlife. However, sometimes when you are too focused, animals surprise you!  There have been numerous occasions when I have been nose-deep in grass and startled by the huff of a deer standing behind me, or surprised by a flush of birds that settled nearby while I was absorbed by scrutinizing glumes and counting florets.  One of my more interesting encounters occurred when I sat up quickly after observing plant cover and came face-to-face with a male ruby throated humming bird (Archilochus colubris). Hummingbirds are capable of hovering in flight, and that sustained moment of mutual alarm and intrigue filled me with awe: moments like these are why I love field work. It is the unexpected encounters, rare findings, and spontaneous invitations to explore nature or observe the interactions of organisms that make long days outside in variable weather worth it.

This is a quadrat (50 cm x 50 cm frame). Here we measure the relative cover of species.

 

I don’t have any pictures of birds but here are some other surprises. A baby pronghorn, and North American long-tailed weasel–observing the researchers from a distance of course.

Naturalism and botany, which often provide a foundation in taxonomy, can be a gateway into many other disciplines, and once you master one taxa the mind can wander onto new research questions and other organisms. If you look down and look beyond the grass while in the prairie, you will discover an intriguing community layer of cryptogamic organisms like lichen, mosses, and spike-mosses called a biological soil crust. Soil crusts can cover up to 90% of the soil surface, contribute cryptic biodiversity to the ecosystem, prevent soil erosion, and fix atmospheric nitrogen and carbon! For my Ph.D. research, I have incorporated this community into my understanding of seed bank composition in Dry Mixedgrass Prairie disturbed by oil and gas pipelines. Organisms like lichen, which can have delicate branches, cups, and leaf-like bodies, are sensitive to disturbance and recover extremely slowly. Although they are an intrinsic attribute of grasslands, many botanists, like me, are unaware of them and policies regarding the reclamation and revegetation of industrially disturbed areas in prairies ignore these organisms.

These are some lichens you can find in prairie soil crusts. The white crusty species on the left side (Diploschistes muscorum) is called cow-pie lichen in common vernacular.

Working in the field, I value the independence and the time allowed for self-reflectance while wandering a tortuous path to a survey location. The ritual of parking, packing, swinging a quadrat over my shoulder and scouring my path for any unique organisms or movement in the grass is an experience I look forward to every field season. However, grasslands are sensitive, fragmented ecosystems.  Although they are often described as ‘marginal’ or ‘waste’ lands, grasslands are in fact the most threatened and least protected ecosystem in Canada, as is easily demonstrated by driving across Alberta, Saskatchewan, and Manitoba on the Trans-Canada Highway observing a patchy mosaic of cultivated fields with small margins of native grass and trees remaining along hillsides, coulees, and wetlands.  As a young ecologist, I want to communicate the irreplaceable and invaluable ecosystem services (carbon storage, biodiversity, water purification, etc.) prairies provide as they benefit society and host understudied taxa and ecosystem processes.

Surveying pipeline disturbance. Those cute calves chewed holes in that measuring tape after this photo was taken.

 

Lysandra studies rangeland ecology and management at the University of Alberta. Her Ph.D. research addresses grassland disturbances and land use history on soil seed banks, plant communities, and soil. You can find her on Twitter at @GrasslandNerd 

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One thought on “Prairies provide cryptic, undervalued, and threatened biodiversity

  1. Pingback: Haaaaapppppy Birthday to you! | Dispatches from the Field

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