A Colorado Jewel: Southeastern Prairies and Canyonlands

A Regional Perspective

The Central Shortgrass Prairie (CSP) ecoregion covers 56 million acres across seven states. Grasslands are among the most highly altered of all ecosystems worldwide, and this is true in the CSP ecoregion as well. The one exception is the southwestern portion of Colorado's eastern plains, where native grasslands, juniper savannas, and canyons still retain much of their historic integrity and support many species of conservation concern. Many conservation organizations and government agencies have documented the significance of this intact landscape for conservation of declining prairie species.

The Prairies: grasslands and the species they harbor

Colorado has lost roughly 48% of its historic native grasslands - a loss rate that is more than twice as high as that experienced by any other large-scale ecological system in the state. The remaining grasslands cover about 22% of Colorado, but are significantly under-represented in the state's portfolio of legally protected landscapes. With the exception of wetland and aquatic habitats, grasslands support more than twice as many animal species of concern when compared to other habitats, including forests and shrublands, which both cover approximately the same percentage of land as grasslands (roughly 19-21%). Grassland habitats are particularly important for birds and mammals.

Canyonlands: it's all about the water

The canyon topography of southeastern Colorado is unique in the prairie ecosystem, and supports juniper woodland and savanna communities that provide very distinct habitas. The hydrologic system around the Purgatoire is the least altered of all plains river systems. Plant and animal communities in this system are much healthier and more diverse than those found in any other hydrologic system on the plains. The region's canyonlands are a state hotspot for rare ferns, and contain one of the highest concentrations of plains leopard frogs in the state.

Some of Colorado's Rarest Plants

The worldwide distribution of four plant species is restricted to barrens habitats in and near the study area. Land management in this region will determine the fate of these species.

The Ranching Legacy and Future Management

In stark contrast to the remainder of Colorado, the vast majority of the state's eastern plains are privately owned, with agriculture forming the basis of local economies. With the loss of the prairie's most significant native grazer - the bison - cattle grazing has become a crucial ecological process for maintaining habitat conditions on the prairie. The number of places supporting species and habitats of conservation concern is testament to the on-going stewardship of Colorado's ranching families. The future of our prairie ecosystem rests in their hands. In order to maintain the current level of ecosystem integrity and species health, it will be crucial for future management of the rangelands to ensure:

• healthy blue grama communities,
• an intact hydrological regime, and
• a mosaic of grass, shrub, barren, and woodland/savanna patches to provide for the varied needs of all native prairie inhabitants.

Survey Results

During the summers of 2007 - 2009, the Colorado Natural Heritage Program's biologists and partners surveyed 26 private ranches in southeastern Colorado. Researchers documented 123 species and plant communities of conservation concern, including 41 animals, 36 plants, and 46 communities. To date, these species and communities have been documented at over 2,400 of discrete locations across the landscape. Future surveys would undoubtedly document additional locations.

This project was a collaborative effort among southeastern Colorado's private landowners and biologists from the Colorado Natural Heritage Program, Denver Botanic Gardens, Rocky Mountain Bird Observatory, and Colorado State University's Larval Fish Laboratory. For more information, please see our reports page. The above text, with more great pictures and graphics, is also available as a brochure.

New Zoology Field Technician positions open

We are looking for up to 12 seasonal zoology field technicians to survey for mammals, amphibians, birds, and invertebrates this summer. Sites will be in various locations throughout the state. These positions will require extensive travel, some camping, and long days in the field. These positions may also involve properly collecting and preparing specimens for identification when appropriate.

Position timeframe: Approximately May 1, 2010 through October 31, 2010 and will vary depending upon project.

First consideration of applicants will begin March 31, 2010, but positions will remain open until filled. For more information about these positions and how to apply, please see the announcement on the Employment and Volunteering page of our website.

Field techniques - Frequency

CNHP ecologists use frequency of occurrence as a measure of plant community composition, especially if we want to know how the community is changing over time.

Reading a frequency frame placed along a transect.

Frequency is usually expressed as a percentage, such as the percent of all plots in which a species is present, or the percent of cells in a grid that contain the species. It is a presence/absence measurement, and does not reflect the number of individuals or the area they cover. A little reflection tells us that frequency is highly dependent on the size of the area being observed – if our sample frame is the size of the earth, every species has a frequency of 100%!

Since we don't always know in advance what size frame will be appropriate for detecting changes in species frequencies, and because some species are much bigger than others, it is common to use a "nested" frequency frame like this, placed at many different locations in the area being studied:

This frame can easily be made out of plastic pipe and elbow fittings. Divisions can be marked with strings, or marks along the frame edge. To read the frame, record a 1 if the species is in the smallest square, a 2 if it is in the 1/10th m square but not the 1/100th, and a 3 if it is only in the largest square outside the other two squares. A species that gets a 1 is present in all three frame sizes, but a species with a 3 is only present at the largest frame size. Calculate the percent of "present" frames for each species at each size frame. To detect change over time, a frame size that gives a percentage between 20 and 80 is best.

Quiz time! Assuming the nested corner is upper left in the photo,
is the dog is a 1, 2, or a 3?

(A: we're sampling plants here, shoo!)

2009 Southeast Colorado survey report now available

The most intact portion of the Central Shortgrass Prairie ecoregion is in southeast Colorado, in private ownership. In 2007 and 2009, landowners requested biological inventories of their properties by the Colorado Natural Heritage Program, so the landowners might obtain data pertinent to their stewardship, future management decisions, and ecosystem credit values.

This study was made possible with support from Great Outdoors Colorado, Colorado Division of Wildlife, Colorado Cattlemen’s Agricultural Land Trust, Colorado State Land Board, The Nature Conservancy, Natural Resource Conservation Service, and private landowners.

Our surveys have confirmed that southeast Colorado is a biological hotspot. CNHP mapped over 2400 mapped locations of 41 rare species of animals, 36 of rare plants, and 46 plant communities of conservation concern.

The results of the 2009 surveys are now available in the report Southeastern Colorado Survey of Critical Biological Resources 2009 Addendum to the 2007 Survey.  Both this and the report for the 2007 surveys are available on the Documents and Reports page of our website.

Site Profile: Troublesome Creek, Grand County

B1: Outstanding Biodiversity Significance

This site was visited during 2005 as part of the Grand County Inventory. Troublesome Creek joins the Colorado River east of Kremling. The site is dominated by the sandstones and siltstones of the Troublesome Formation, which are generally sparsely vegetated. These fine-textured, grayish-brown soils may not look like much, but are home to two Grand County endemic plant species that are Federally Listed as Endangered: Penland beardtongue (Penstemon penlandii) and Osterhout milkvetch (Astragalus osterhoutii), as well as the regional endemic dog parsley (Aletes nuttallii).

Osterhout milkvetch (Astragalus osterhoutii)

This site includes all known occurrences for Penland beardtongue. Due to the concentration of globally critically imperiled (G1/S1) plants, this site is of outstanding biodiversity value, in essence irreplaceable.

Penland beardtongue (Penstemon penlandii)

Doubling our assets

CNHP has been busy in the 21st century! Over the past decade, the number of mapped locations of rare plants, animals and communities nearly doubled in our BIOTICS database, jumping from 11,577 to 23,068 mapped locations. That’s a lot of ground covered and a lot of digitizing.

A big thanks to all of our partners who made this possible by funding field work, submitting data and supporting our mission.

6-8 new Field Technician positions now open

The Center for Environmental Management of Military Lands together with CNHP anticipate a need for up to 8 technicians for field work at two project sites along the Upper Missouri River in Montana. The work requires field botany or field ecology skills, GPS, and map reading and navigation skills. Knowledge of plant taxonomy and species identification is required; experience identifying flora of the northwestern Great Plains is beneficial.

Successful applicants will sample vegetation communities on lands surrounding two US Army Corps of Engineer reservoirs. Field technicians will navigate to remote plot locations via foot, boat, and/or automobile and document plant community and environmental characteristics using maps, imagery, GPS, and vegetation keys.

Anticipated position timeframe: June-October, 2010.

These positions are open until filled. For more information about these positions and how to apply, please see the announcement on the Employment and Volunteering page of our website.

Update on Natural Heritage Methodology Training

Teleconferenced participants in VA and MA watch and listen to a presentation in Colorado.

We're on day 3 of our 4 day Natural Heritage Methodology training session, here in Fort Collins and concurrently in Virginia and Massachusetts.  There are 32 participants, two thirds of which are attending here at CNHP's office in Colorado State University.  We are teleconferenced in with the other two locations, so that trainers can give their talks at any of the 3 locations, and all attendees can participate equally.

Lessons in basic methodology were punctuated by specific examples and exercises.

In addition to participants from CNHP, attendees represent California Academy of Sciences, California Dept. of Fish and Game, Lousiana Natural Heritage Program, Maine Natural Areas Program, Michigan Natural Features Inventory, Mississippi Museum of Natural Science/Heritage Program, Montana Natural Heritage Program, National Park Service, NatureServe, Nebraska Game and Parks Commission, New York Natural Heritage Program, Parks Canada, Tennessee Valley Authority, The Nature Conservancy (Texas Chapter), US Fish and Wildlife Service, Virginia Division of Natural Heritage, Western Timberland Research, Wisconsin Dept. of Natural Resources, and the Wyoming Natural Diversity Database.

Smiling participants here in Colorado.

 Breakout session to apply what we have learned.

It has been long days full of detailed information and breakout discussions and exercises.  Yesterday, we took a quick yoga break, and today we hope to break early to take field trips.  Our field trip here is to the Soapstone Prairie Natural Area.

 

Yoga Break!

Colorado tarantula

Did you know that Colorado has its own species of tarantula? CNHP ecologist Renée Rondeau took these photos of our endemic tarantula, Aphonopelma coloradanum, in Pueblo County last fall.

Now, now, he's just as scared of you as you are of him.

These large furry spiders may be seen in the southeastern corner of the state, as far north as Colorado Springs, especially during the mating season from late August through November. Most tarantulas out and about are mature males, looking for mature females.

Gee, Renée, what's that moving around in your backpack?