Tuesday, February 26, 2013

Mapping warm water sloughs on the South Platte

by Jeremy Sueltenfuss, CNHP Wetland Ecologist

For many years, our partners in the wildlife community have talked at length about the importance of warm water sloughs for overwintering Colorado wildlife.  As they are continually recharged by emerging groundwater, which is not subjected to the freezing temperatures at the surface, these stream-like features are some of the only water bodies across the landscape that remain open throughout the winter, providing wildlife much needed access to water during the cold winter months.  Because of their importance, we set out to map all the sloughs we could find along the South Platte River.  While aerial imagery can be quite good at mapping water features, nothing beats a low altitude flight to get a sense of the landscape!

Though familiar with the more common method of flying (being inside the plane that is), Jacqui thought she would give this method a shot.  It did not last long.  An immense thanks to Colorado Parks and Wildlife for supplying us with their plane and the CPW pilot, Brian, for a very safe and rewarding experience.  
Taking off in a small four seat prop plane from the Fort Collins – Loveland airport (Fort Love as our pilot referred to it), Jacqui, a fearless CNHP work-study student and I put our faith in our pilot, Brian.  Brian has been flying for Colorado Parksand Wildlife (CPW) for years, and his knowledge of both the landscape and local wildlife was tremendously beneficial.  Beyond his ability to spot herds of deer, gaggles of geese, and flocks of turkey from amazing distances, his stories from his work for CPW were breathtaking.  While I love hiking to remote mountain lakes, I have never thought about what it takes to stock them with fish.  Brian’s stories of maneuvering his small plane through tight mountain corridors, dropping his air speed to levels I personally never wish to feel while in flight, and releasing hundreds of small fish at precisely the right moment for them to land in the lake, all while watching the rock face in front of you fill your vision, was enough to make me sweat.  Luckily for us, the only aerial acrobatics we performed were slow broad circles to get a closer look at a slough, or a better view of some wildlife. 

Continually being recharged by groundwater, warm water sloughs remain slightly warmer than other surface waters and remain open throughout the winter.  This provides much needed access to water for wildlife in the area.
Though “Colorful Colorado” is quite brown in the winter, flying at 150 feet over the South Platte was fascinating and beautiful.  As promised, sloughs seemed to be the only open water around, and the leafless trees afforded views of the many flocks of waterbirds, small herds of deer bounding away, and even a few scenes of male turkeys doing their best to impress a nearby female.  The seven bald eagles we saw perched in trees or soaring above the river provided a wonderful example of an Endangered Species Act success story and served as tribute to the tremendous effort of conservation groups over the past 50 years.  It was enough to almost forget what we were after!  Armed with maps of sloughs we had completed before the flight using imagery from the summer, we constantly compared what was in our maps to what we were seeing on the ground.  Both Jacqui and Brian seemed to do quite well looking down at maps and back out at the landscape for 4 straight hours.  While I did my best to appear absolutely normal, my stomach was reenacting what it must feel like to stock those high mountain lakes!  Queasiness aside, we accomplished our goal and came away with a highly accurate map of the warm water sloughs along the South Platte River between Greeley and the state line.  Though many other riparian landscapes across the state contain warm water sloughs that may one day be mapped, I have high hopes this data can be used for the restoration and the conservation of lands containing these important features.     

Thursday, February 14, 2013

Updated Specimen Information on Rocky Mountain Herbarium Website

The Rocky Mountain Herbarium online database has been updated to include specimens from floristics projects in the Medicine Bow National Forest (WY side), Vermejo Park Ranch (NM), Lewis and Clark National Forest (MT) and the Comanche and Cimarron National Grasslands (CO and KS). If you want to explore the specimens and their mapped locations on Google Earth, visit the Rocky Mountain Herbarium Specimen Database.

A tiny lace hedgehog cactus (Echinocereus reichenbachii)
growing on a shale outcrop above the Purgatoire River. 

The Comanche National Grassland of SE Colorado has a unique flora that includes elements of prairie species such as purple coneflower (Echinacea angustifolia), mixed with montane/foothill species like Gambel oak (Quercus gambelii).  If you are looking for new places to explore in Colorado, this area can be a warm and sunny haven in late April and May. Bring your flora, plenty of water, and maybe even your mountain bike.

The Purgatoire River Valley dotted with oneseed juniper (Juniperus monosperma)
and mountain mahogany (Cercocarpus montanus).

Tuesday, February 12, 2013

Wanted: Wetland Ecology Field Technicians for Summer 2013 work!

The Colorado Natural Heritage Program (CNHP) at Colorado State University (CSU) seeks 4–6 experienced field technicians for summer field work assessing the condition of wetlands throughout the lower South Platte River Basin. All positions require field botany or ecology skills. Knowledge of plant taxonomy and species identification required. Preferred qualifications include experience in wetland or riparian ecology, knowledge of local flora, and familiarity performing field work for long days (10+ hours).

Fieldwork will take place in randomly selected wetlands in urban areas, agricultural areas, and more remote natural areas as part of wetland condition and wildlife habitat assessment. Standard duties will involve driving and hiking to field sites; in-field plant identification and in-office plant identification with a microscope; extensive collection of vegetation, soil, wildlife habitat, and environmental data; detailed completion of field survey forms; and landowner interactions.

For more details and to find out how to apply, read the full announcement here!

Thursday, February 7, 2013

New Report: Treeline Monitoring in the San Juan Basin Tundra

Mountain ecosystems, particularly alpine, are among the most vulnerable to climate change. Warming conditions are likely to cause trees and shrubs to encroach into alpine tundra habitats, which are home to many species found nowhere else.

CHNP, in cooperation with the Bureau of Land Management, U.S. Forest Service and Colorado College, began a pilot project to monitor treeline expansion in the San Juan mountains. A combination of fieldwork and spatial analysis was used to determine if the treeline on the southwest slope of Kendall Mountain had changed in the last 50 years.

Aerial imagery from 1951 and 2011 were used to establish transects perpendicular to the treeline to detect growth of new trees upslope, which would indicate an upward advancement of trees into alpine areas. The location of trees along these transects were then field verified, and a subset of trees were cored to determine their age. Additionally, the density of trees below the treeline was calculated for both time periods.

Recruitment above treeline
Results show that the treeline has not advanced significantly in the last 50 years. However, there are signs of upslope recruitment (trees between 20-50 years old above the current treeline, but not in sufficient density to form a new treeline). Should this area of new recruitment continue to fill in and become the new treeline, it will be 160 feet above the existing line. Additionally, tree density below the current treeline has increased by approximately 12% in the last 50 years. All tree cores taken demonstrated an increase in growth rate since 1996.

For more information, see the complete report. We hope to expand this pilot project to study more treelines throughout the San Juan mountains, to determine if these increases in growth rate and tree density are consistent trends that can be correlated with measured increases in average summer temperatures.