Biological Assessment of Cook Ranch, Albanycounty,Wyoming

Biological Assessment of Cook Ranch, Albanycounty,Wyoming

BIOLOGICAL ASSESSMENT OF COOK RANCH, ALBANYCOUNTY,WYOMING 2002 PROJECT REPORT Prepared by: Bonnie Heidel, Lead Botanist Gary Beauvais, Director Jason Bennett, Research Zoologist Douglas Keinath, Lead Zoologist Wyoming Natural Diversity Database - University of Wyoming 25 March 2003 The enclosed series of 5 reports details biological investigations of the Cook Ranch (Albany County, Wyoming) performed by staff of the Wyoming Natural Diversity Database (University of Wyoming) at the request of the Wyoming Field Office of The Nature Conservancy (Lander, Wyoming) and in cooperation with Cook Ranch owner A. Cook. These reports are intended to enhance the information presented in the 2001 project report. Five major topics are discussed: Waterbird surveys Amphibian surveys Riparian small mammal surveys Mountain plover surveys Rare plant surveys WATERBIRD SURVEYS: Lake lone - Cook Ranch, Albany County, Wyoming Prepared by : Jason Bennett, Research Zoologist Gary Beauvais, Director Wyoming Natural Diversity Database - University of Wyoming 25 March 2003 The Laramie River and the system of lakes found in the Laramie Valley, collectively called the Laramie Lakes, are important breeding centers for many species of waterfowl and shorebirds ( collectively referred to as "waterbirds"). These waters are also important during migration as staging and stopover sites for various waterbirds. The Cook Ranch (Albany County, Wyoming) supports a large segment of the Laramie River and several wetlands and closed-basin lakes used by waterbirds, and as such may provide critical habitat for many species during migration and the breeding season. Zoologists from the Wyoming Natural Diversity Database (WYNDD; University of Wyoming) conducted waterbird surveys along a portion of the Laramie River and several lakes on Cook Ranch over 9 days during summer and fall 2002. Due to extreme drought, the river was low and most of the lakes on the Ranch were completely dry. The largest lake on Cook Ranch is Long Lake, which at the high water mark has a surface of about 3.5 krn2 of open water, but on average covers less, and in 2002 was completely dry. Due to irrigation efforts Lake Ione remained wet 2 and attracted many birds throughout the survey period. There was approximately 0.1 krn of open water and 2.5 k:m2 of adjacent wetland in the Lake Ione basin. This was the only lake on the Ranch that received regular waterbird surveys during 2002; this report consists of the results from only those regular surveys. To provide a comparison to other lakes in the Laramie Valley, Hutton Lake National Wildlife Refuge (NWR) was also surveyed for waterbirds over 9 days during the same period. Hutton Lake NWR is located 18 km southwest of the town of Laramie and consists of 5 clustered lakes; 2 2 Hutton (0.8 km\ Creighton (0.8 k:m ) , Hoge (0.3 km2), Rush (0.2 km\ and George (0.1 km ). The surface areas provided are typical of wet years; in 2002 Creighton and Rush Lakes were 2 completely dry and the others were very low. There was an estimated total of 1.5 k:m of open water available at Hutton Lake NWR, and virtually no emergent vegetation, during the waterbird surveys. A total of 32 waterbird species was observed at Lake Ione (Table 1). Of these, 22 species were confirmed or likely breeding in the immediate area. Breeding status was determined by behavior or the presence of young. The remaining species were either transient or observed during migration. Lake Ione was consistently occupied by 200-500 individual birds on the open water or shoreline, but it is important to note that a large portion of the lake's vegetated wetlands provided dense cover. The extent of the wetlands and density of the cover made it impossible to provide accurate counts. On many occasions several hundred ducks were observed in flight above the wetland while several hundred more remained on the lake surface. It is likely that the Lake Ione basin was occupied by several thousand waterbirds during survey period. A total of24 species was observed at Hutton Lake NWR (Table 1). Of these, 14 species were confirmed or likely breeding in the immediate vicinity. Waterbird abundance at Hutton Lake NWR never approached that observed at Lake Ione, most likely due to the much greater coverage of wetland vegetation at Lake Ione. Two species were observed at Hutton Lake NWR that were not observed at Lake Ione; conversely, 10 species were observed at Lake Ione that were not observed at Hutton Lake NWR (Table 1). Due to irrigation efforts and immediate proximity to the Laramie River the Lake Ione basin remained wet while most other lakes in the Laramie Valley in general, and Cook Ranch in particular, were low or dry. In this context, Lake Ione can be seen as an ecological refuge for waterbirds during times of extreme drought, as was experienced in 2002. During periods of more normal precipitation the Laramie River corridor and other wetlands and lakes on the Cook Ranch would undoubtedly attract multitudes more waterbirds, maintaining the position of the Ranch as one of the most productive waterbird centers in the Laramie Valley. WYNDD recommends continued survey for waterbirds in upcoming seasons, with an emphasis on documenting rare and sensitive taxa. Table 1. Species of waterbirds observed on Cook Ranch (Lake Ione) and Hutton Lake National Wildlife Refuge, Albany County, Wyoming, summer 2002. Status: C = confirmed breeder, L = likely breeder, T = transient, M = migrant, X = not observed. Abundance: A = abundant, C = common, U = uncommon, R = rare, X = not observed. Species shown in bold were unique to Cook Ranch (Lake Ione); species shown in italics were unique to Hutton Lake National Wildlife Refuge. Status Abundance Status Ab undance Common Name Cook Hutton Cook Hutton Common Name Cook Hutton Cook Hutton Pied-billed Grebe L X u X Ring-necked Duck M X R X Eared Grebe C L A C Lesser Scaup M T R u Western Grebe M X R X Common Meraanser M T u R lAmerican White Pelican M T u R Ruddv Duck T L u C Black-crowned Niaht Heron L X R X Sora L X R X Great Blue Heron X T X R !American Coot C X A X !White-faced Ibis L X R X Killdeer C L A C Canada Goose C C C A American Avocet C L A A Gadwall L L C C Lesser/Greater Yellowlegs M M u R American Widqeon L L A C Willet C L A C Mallard C C A C Spotted Sandoioer L X C X Blue-winaed Teal L L A C Unidentified Sandoioer (Baird's? M M R R Cinnamon Teal L L A C Common Snipe L X C X Northern Shoveler L T u R !Wilson's Phalarooe L L A A Northern Pintail L T u C California Gull T M R R Green-winqed Teal L L C C Black Tern M X R X Canvasback T T R u Forster's Tern X R X R Redhead L L C C AMPIDBIAN SURVEYS: Lake Ione - Cook Ranch, Albany County, Wyoming Prepared by : Gary Beauvais, Director Douglas Keinath, Lead Zoologist Wyoming Natural Diversity Database - University of Wyoming 25 March 2003 Lake Ione and its surrounding wetland (Cook Ranch, Albany County, Wyoming) represent a large and potentially very high-quality habitat for various species of amphibian. Common taxa such as boreal chorus frogs (Pseudacris triseriata) and tiger salamanders (Ambystoma tigrinum) almost certainly occur here. Rarer and more sensitive taxa such as northern leopard frogs (Rana pipiens) are also likely occupants. This site is within the historic range of the Wyoming toad (Bufo baxteri), which was documented on the Laramie River only a few miles upstream of Lake Ione in 1941 and again in 1963. Subsequent surveys for this extremely rare (listed Endangered under the U.S. Endangered Species Act, May 1973) toad in this area have failed to document its presence. Free-ranging Wyoming toads are now thought to be restricted to a small and highly­ managed population at Mortensen Lake approximately 35 mi south-southwest of Lake Ione. The USDI Fish and Wildlife Service has recently committed to re-introductions of Wyoming toads into several wetlands within their historic range in the Laramie Valley. Captive-bred toads will be released into as many as 5 new sites in summer 2003. The segment of the Laramie River crossing Cook Ranch, along with large associated wetlands such as Lake Ione, may be suitable for the establishment of additional free-ranging populations of Wyoming toads. The Ranch supports an order-of-magnitude more contiguous habitat than other sites currently being considered for reintroduction; it could potentially support a very large number of free-ranging toads. Thus establishment of Wyoming toads here would contribute substantially to the species' recovery. Zoologists from the Wyoming Natural Diversity Database (WYNDD; University of Wyoming) surveyed Lake Ione and the surrounding wetland for amphibians on 2 days in summer 2002. The purpose of this survey was to (1) document amphibian species inhabiting the area, and (2) capture individual amphibians to submit to diagnostic laboratories for an analysis of chytrid fungus presence. Chytrid fungus was a major cause of Wyoming toad decline and continues to be the main obstacle to recovery of this species. Lake Ione has been suggested as a possible reintroduction site for Wyoming toads; its value as such will be largely determined by whether or not chytrid fungus is present. One half-day-long survey was conducted in late July, and another in mid-August. Each survey involved foot searches by 2 teams of 2 observers each, with each person equipped with waders and capture nets.

View Full Text

Details

  • File Type
    pdf
  • Upload Time
    -
  • Content Languages
    English
  • Upload User
    Anonymous/Not logged-in
  • File Pages
    22 Page
  • File Size
    -

Download

Channel Download Status
Express Download Enable

Copyright

We respect the copyrights and intellectual property rights of all users. All uploaded documents are either original works of the uploader or authorized works of the rightful owners.

  • Not to be reproduced or distributed without explicit permission.
  • Not used for commercial purposes outside of approved use cases.
  • Not used to infringe on the rights of the original creators.
  • If you believe any content infringes your copyright, please contact us immediately.

Support

For help with questions, suggestions, or problems, please contact us