las vegas wash coordination committee lvwash.org Proposal to Conduct a Small Mammal Study in the Las Vegas Wash, Nevada March 2009
Proposal to Conduct a Small Mammal Study in the Las Vegas Wash, Nevada SOUTHERN NEVADA WATER AUTHORITY Environmental Monitoring and Management Division Prepared for: Research and Environmental Monitoring Study Team Las Vegas Wash Coordination Committee Prepared by: Marissa Foster Southern Nevada Water Authority 100 City Parkway, Suite 700 Las Vegas, Nevada 89106 March 2009
Proposal to Conduct a Small Mammal Study in the Las Vegas Wash, Nevada Table of Contents Page No. 1.0 INTRODUCTION...1 2.0 GOALS OF THE STUDY...2 3.0 METHODS...2 3.1 Survey Design...2 3.2 Budget...4 3.3 Participants...4 3.4 Safety...4 4.0 LITERATURE CITED...4 List of Tables Table 1. Small mammal budget....4 List of Figures Figure 1. Survey boundary...2 Figure 2. Transect design...3 List of Appendices Appendix A Field guidelines for mosquito protection Proposal to Conduct Las Vegas Wash Small Mammal Study ii
1.0 INTRODUCTION The Las Vegas Wash Coordination Committee (LVWCC) is a group consisting of citizen members and local, state, and federal agencies. In 2000, the LVWCC developed the Comprehensive Adaptive Management Plan (CAMP) for the purpose of designating activities to restore and sustain the habitats of the Las Vegas Wash. This document has recommended actions that have been implemented in order to prevent any further degradation of the Las Vegas Wash (Wash). One of the recommended actions was to create a long-term fish and wildlife management plan. In 2008, the Las Vegas Valley Watershed Advisory Committee (LVVWAC) approved the Las Vegas Wash Wildlife Management Plan (WMP) to meet this recommendation. The WMP listed its own set of recommended actions which were classified into three management objectives: to conserve the abundance and diversity of native wildlife species that have been found along the Wash, protect and enhance wildlife habitats, and increase environmental awareness of these resources in the community (Shanahan et al. 2008). Bradley and Niles (1973) were the first to conduct a baseline inventory in the Wash in 1972. During these surveys, they listed species that have not been documented by any other surveys that have taken place in the Wash since. In order to conserve the abundance and diversity of native wildlife species that have been found along the Wash, the WMP plan recommended baseline monitoring of specific species that were not adequately inventoried by recent efforts. One of the baseline monitoring recommendations was to conduct small mammal trapping in marsh habitats for the western harvest mouse (Reithrodontomys megalotis; Shanahan et al. 2008). There have been two small mammal (mammals less than one pound) surveys conducted along the Wash. The first surveys were conducted in 1972 by Bradley and Niles (1973). Over the last 35 years, Wash habitats were altered greatly due to storm events causing erosion. In 2002, a small mammal survey was conducted in the Wash. From this survey, three documents were published, two of the documents were masters theses (Herndon 2004 and Larkin 2006), written by students that assisted on the project, and the other document was written by the lead biologist (Gerstenberger et al. 2004). The study focused on creosote bush, salt bush and salt cedar habitats. Bradley and Niles (1973) found the western harvest mouse in higher abundance in the woodlandmarsh habitats while Gerstenberger et al. (2004) had limited sites in this habitat type (Shanahan et al. 2008). Since the riparian habitats have not been trapped since 1972, the status of small mammals in marsh and other wet environments at the Wash is currently unknown (Shanahan et al. 2008). This project proposes to describe the research that will be done in marsh-woodland areas in the Wash. Marsh-woodland habitats cover areas from emergent vegetation to shoreline vegetation. Shoreline vegetation will be limited to woodland vegetation in flood plain areas close to the water. Since the Wash has drastically changed since 1972 when Bradley and Niles documented the western harvest mouse, these data will fill the 35 year gap of information on the diversity and relative abundance, as well as determining the temporal changes that have occurred for small mammal species in the marsh and riparian habitats in the Wash. Once data have been collected and analyzed, land managers in the Wash will be been given the informational tools they need to make decisions that incorporate specific management actions which could reduce threats to these species and to propose site-specific conservation actions. Proposal to Conduct Las Vegas Wash Small Mammal Study 1
2.0 GOALS OF THE STUDY The purpose of this proposal is to document diversity, relative abundance and temporal changes of small mammals in woodland-marsh habitats along the Wash using live capture survey techniques. This study will result in information about the small mammals that use woodland-marsh habitats in the Wash and will help with the long-term management and conservation of identified species. These data will provide LVWCC member agencies (e.g., Clark County Parks and Recreation, U.S. Fish and Wildlife Service, National Park Service, Bureau of Reclamation, Nevada Department of Wildlife, Southern Nevada Water Authority, etc.) with a data-set of information from which to assess how future activities are impacting wildlife and habitat in the Wash. 3.0 METHODS 3.1 Survey Design This survey will be conducted from March September over a one-year period. The survey will be conducted through the summer months. The study area will be from the intersection of the Wash and Vegas Valley Drive downstream to Lake Las Vegas Resort. Figure 1: Survey boundary. Proposal to Conduct Las Vegas Wash Small Mammal Study 2
The Wash is under constant construction and this may affect habitats where animals may be found. Biologists will focus on, but will not be limited to, the riparian and marsh habitats located in Wash revegetation sites. This survey will evaluate at minimum four study sites per month. Each site will be studied for two consecutive nights and we will use line transect methods. The trapping array on each site will consist of four transects, two parallel lines with two diagonal lines attached to the parallel at a 45 degree angle (Figure 2). If for any reason the four transects cannot be set, at a minimum, two parallel transects will be used for each site. Each transect will have a maximum of 40 traps per transect. The traps will be set, on average, five meters apart. At maximum, transect lines will be 200 meters long. Figure 2: Transect design. Each trap will be baited with a seed, oat and peanut butter mixture and placed in emergent vegetation (e.g. reeds, cattails, and bulrush) or on the ground. The traps will not be opened until sunset to prevent animals from getting caught in the traps during the day. All traps will be checked first thing the following morning. Animals will be processed, marked, and released. Once the animal is released, the traps will be baited again and set for the second night. Each day, biologists will process the trapped animals by recording the species, sex, reproduction status, age, weight, and if the animal has been captured before. Western harvest mice, one of the animals of interest in this study, weigh between 8 10 grams. These animals are difficult to mark without causing a reduction in mobility or health. To prevent harming these animals, we will use hair clipping as our marking technique. This involves the biologist trimming a small section of hair on the animals back side. Trimming does not last for long periods of time, therefore mark recapture estimates of abundance will be reported on a monthly basis. Biologists will use the first year of the study to determine what areas the small mammals are using for habitats. In the following year of the study, habitats where animals were not detected will be removed from the survey. Diversity will be determined by the number of species that are Proposal to Conduct Las Vegas Wash Small Mammal Study 3
caught, while abundance will be determined by the number of animals trapped per night. Both of these measurements analyses will also be evaluated by habitat type. The Las Vegas Wash Coordination Project Team (Project Team) office will be responsible for all data investigation and analysis. A summary report indicating all findings will be completed and provided to the LVWCC and the Research and Environmental Monitoring Study Team upon conclusion of the survey. Project updates will be provided to the LVWCC and the Research and Environmental Monitoring Study Team during regular meetings. 3.2 Budget Small mammal live traps will be borrowed from other Southern Nevada Water Authority (SNWA) biology teams. The budget reflects replacement costs for broken or stolen traps (Table 1). Bait, however, will need to be purchased for luring animals into the traps. Item Amount Price Humane Sherman Live Traps 50 $ 900.00 Bait (seed) and peanut butter 2 $ 100.00 TOTAL $ 1,000.00 Table 1: Small mammal budget. 3.3 Participants A Project Team biologist will train survey participants on field collection methods and animal handling. This biologist has been trained by Dr. Michael J. O Farrell, a well known small mammal expert, in these specific field techniques. The Project Team will be responsible for the coordination, development, and implementation of this study. 3.4 Safety Personnel participating in the survey will travel in groups of two or more people. Staff will follow all preventative measures to ensure their safety and the safety of additional field personnel participating in investigative efforts. Since some mammals are known for carrying rabies, all personnel handling the animals should have up to date rabies vaccinations and their titer levels checked. Project Team staff will follow all division safety protocols including the field guidelines for West Nile protection (Appendix A). The West Nile protocol meets and exceeds the recommended guidelines developed by UNLV (Jim Pollard and Gretchen Andrew). Personal involved in this survey will also be informed of Plague and Hanta Virus symptoms and actions to preventing Hanta Virus and/or Plague infection. 4.0 LITERATURE CITED Bradley W.G. and W.E. Niles. 1973. Study of the impact on the ecology of Las Vegas Wash under alternative actions in water quality management. Final report to the Las Vegas Valley Water District. Gerstenberger, S.L., C.L. Cross, and D. Divine. 2004. An investigation of small mammal diversity, population estimates and vegetative characteristics in the Las Vegas Wash. University of Nevada, Las Vegas, Nevada. Proposal to Conduct Las Vegas Wash Small Mammal Study 4
Herndon, C.T. 2004. Vegetation characteristics associated with small mammal populations in the Las Vegas Wash. Thesis. University of Nevada, Las Vegas, Nevada. Larkin, J. 2006. An evaluation of small mammal populations in the Las Vegas Wash. Thesis. University of Nevada, Las Vegas, Nevada. LVWCC (Las Vegas Wash Coordination Committee). 2000. Las Vegas Wash Comprehensive Adaptive Management Plan. Las Vegas Wash Project Coordination Team, Southern Nevada Water Authority, Las Vegas, Nevada. Shanahan, S.A., D.M. Van Dooremolen, T. Sharp, S. Martin and B. Brown. 2008. Las Vegas Wash Wildlife Management Plan. Las Vegas Wash Project Coordination Team, Southern Nevada Water Authority, Las Vegas, Nevada. Proposal to Conduct Las Vegas Wash Small Mammal Study 5
Appendix A
PROCEDURE SUBJECT: FIELD GUIDELINES FOR MOSQUITO PROTECTION NUMBER: 3.4 DIVISION: Environmental Monitoring and Management DATE: 7/16/08 ISSUE: PAGE 1 OF 2 I. PURPOSE When working out in the field April to October, there are guidelines for mosquito protection during different hours of the day. II. DESCRIPTION Dawn to 10:00 am April to October Employees working around water will adhere to the following recommendations: 1. Employees will wear long-sleeved shirts and long pants. Clothing will be sprayed with permethrin for extra protection. Permethrin is manufactured for clothing and is not as effective if sprayed on skin. 2. Employees will apply LVVWD Safety approved DEET products, eucalyptus oil, or picaridin to all exposed skin. In order to avoid spraying the face and hair with DEET, eucalyptus oil, or picaridin, wearing a bug hat with the netting over the head is sufficient. Do not spray repellent containing DEET on the skin under your clothing. Eucalyptus oil and picaridin must be reapplied every hour. DEET products should be reapplied based on the % DEET. Please see Table 1. 10:00 am to 2:00 pm April to October 1. Employees may wear shorts and t-shirts into the field. Employees are expected to use common sense during the 10:00 am to 2:00 pm timeframe. If the employee will be in an area that has reeds or standing water and may have mosquitoes, they should use the Dawn to 10:00 am or 2:00 pm to Dusk requirements. 2. Employees will apply LVVWD Safety approved DEET products, eucalyptus oil, or picaridin to all exposed skin. Do not spray repellent containing DEET on the skin under your clothing. Eucalyptus oil and picaridin must be reapplied every hour. DEET products should be reapplied based on the % DEET. Please see Table 1. If the employee will be in an area that has reeds or standing water and may have mosquitoes they should use the Dawn to 10:00 am or 2:00 pm to Dusk requirements.
FIELD GUIDELINES FOR MOSQUITO PROTECTION PAGE 2 OF 2 2:00 pm to Dusk April to October Employees working around water will adhere to the following recommendations: 1. Employees will wear long-sleeved shirts and long pants. Clothing will be sprayed with permethrin for extra protection. Permethrin is manufactured for clothing and is not as effective if sprayed on skin. 2. Employees will apply LVVWD Safety approved DEET products, eucalyptus oil, or picaridin to all exposed skin. In order to avoid spraying the face and hair with DEET, eucalyptus oil, or picaridin, wearing a bug hat with the netting over the head is sufficient. Do not spray repellent containing DEET on the skin under your clothing. Eucalyptus oil and picaridin must be reapplied every hour. DEET products should be reapplied based on the % DEET. Please see Table 1. Dusk to Dawn April to October Employees working around water will adhere to the following recommendations: 1. Employees will wear long-sleeved shirts and long pants. Clothing will be sprayed with permethrin for extra protection. Permethrin is manufactured for clothing and is not as effective if sprayed on skin. 2. Employees will wear bug hats with mosquito netting. 3. Employees will apply LVVWD Safety approved DEET products to all exposed skin (which should only be the hands). Do not spray repellent containing DEET on the skin under your clothing. Concentrations of DEET have different amounts of protection. Use Table 1 to determine how frequently DEET should be applied. % DEET Hours of Effectiveness 23.8 5 20 4 6.65 2 4.75 DEET and 2% Soybean Oil 2 Table 1: DEET Effectiveness