Friday, August 29, 2008

Butterfly Surveys

Hi Everyone,

We have been doing butterfly surveys this week in the Trumball/Deckers/Hayman burn area. Here's a little about the Pawnee Montane Skipper we are surveying -

This butterfly is native to only one area of the Colorado Front Range. Its habitat is southwest of Denver, where the South Platte River drainage meets up with its north fork. It tends to inhabit dry, open Ponderosa Pine woodland with sparse groundcover at 6,000-7,500 feet. As of right now, it only has 37.9 square miles to call its home as noted by the Denver Water Department. This species' roaming area was bigger in the 60's and 70's, but with the advancement of housing developments and the expansion of Denver's boundaries, the skipper has lost its range and some of its food sources.

The skipper has two main plants that it feeds on. The larvae feed on Blue Grama grass (Bouteloua gracilis) and the adults get their nectar from Prairie Gayfeather or Prairie Blazing Star (Liatris pycnostachya). The adults have been spotted on Musk Thistle, but it is not their primary food source. Both plants are native to the front range of Colorado as well as most of the Midwest.

On September 25, 1987, the Pawnee Montane Skipper was listed on the Federal Endangered Species List as a "threatened" species. The reason for this listing was caused by habitat loss over the last 120 years of fire suppression as well as the growth of conifers and loss of grasslands containing their feeding plants. In 1990, the proposed construction of the Two Forks Dam and Reservoir was not approved by the EPA, because of the immediate threat that would impose on the skipper's habitat. If the construction of the dam had happened, 22% of the skipper's habitat would be lost, which would cause a 23-42% loss in population.

In June of 2002, the Hayman Wildfires charred 138,000 acres of land. This resulted in a 40% decrease in the skipper's habitat. Two previous fires in 1996 and 2000, Buffalo Creek and Hi Meadow, wiped out an additional 10% of skipper habitat. In 1987, Denver Water Department conducted a survey of the Pawnee Montane Skipper population and it was estimated that there was 116,000. Because of the loss of land and feeding plants, the population is estimated to be at least 50-60% less than the previous survey in 1987, but no official survey has been conducted since then.

The recovery plan for the Pawnee Montane Skipper was placed into effect on September 2, 1998. The recovery plan includes monitoring its habitat and removal of less than 5% loss of skipper's habitat to developments such as roads, housing, or recreational. A heavy planting project of the Blue Grama Grass and Prairie Blazing Star (density of 150 or more flowering stems/acre) is planned for. Along with the planting of feeding plants, the project is also aimed at eradicating noxious weeds like Mullen, Knapweed, Russian and Canadian Thistle, Hound's tongue, or any other noxious plant that will compete with the skipper's nutrient plants. The recovery plan is set to end in 2010 and the total cost for the plan is $330,000.

I'm really enjoying this & we have had really progressive results so far, with m the recovery of the skippers looking positive. And no, the butterflies do not actually sit down and fill out surveys for us on how their day was, how they are enjoying their habitat and how many of them there are :) If only it was that easy! We observe how many of the 2 species we see, observe the blue gramma and laitris plants, dead trees, live tress, etc.. The terrain we are traversing each day is pretty steep and we are walking through many snags, dead trees, thistles, and..bees! Unfortunately I was stung on my and a few days ago - my hand has been swollen for the past 2 days now and you can't even see my knuckles!

I have the next 4 days off and will spend my time working on moving & doing things at the new house! I just spoke with Jason for a whole 2 minutes and was able to fill him in on about 10 % of what I had wanted to tell him, I heard a few "mm hmm, ok"'s from him, then he had to go! They are still in northern Nevada on a fire - he did say they may have rains next week and will either change locations or come home :)I miss him so.

Lots to do today, I better get going! Incase you are wondering why I've been slacking on photos, my camera was left at a friend's house in Littleton back in June (after Widespread Panic weekend, go figure), and I have yet to get it back. Perhaps I'll treat myself to a camera for my birthday!

Have a great Labor Day weekend everyone!

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