Covered Species Analysis Support –Final Report 2013-UNR-1460E Photo by Ken Nussear Draft Final report for 2013-UNR-1460E – Submitted to Clark County Desert Conservation Program. January 2020 by Ken Nussear, and Eric Simandle, University of Nevada, Reno 1 Executive Summary Clark County is currently in the process of updating its permit with the US Fish and Wildlife Service (USFWS) to allow for continued development, while planning for the management and conservation of species of concern that reside within the county. The original Clark County Multi-Species Habitat Conservation Plan (MSHCP) included 79 Covered Species, 103 Evaluation Species, and 51 Watch List species (Clark County 2000). The goal of this project was to create habitat models for 17 species that were absent, or that had models reviewed by a previous research effort (by Southwest Ecology LLC; for which the author here was the Principal). Models were incorporated into the previous species accounts from that effort to create a cohesive product with respect to each species. Collectively, this information was in the form of 1) species accounts, which give general species information on biology, 2) status and trends, and 3) habitat considerations produced in the prior effort; and 4) species habitat models –produced under this project – to provide an understanding on the amount and extent of potential habitat for these species. Our approach was to use the species accounts that were produced to drive conceptual models that were used to choose appropriate environmental covariates to use in building species distribution models (SDMs). We received localities for many of the species from the Clark County Desert Conservation Program (DCP), and acquired more localities from a variety of sources to allow for the most accurate modeling possible - given the data. We used three commonly used modeling algorithms to create SDMs; Maximum Entropy (MaxEnt), General Additive Models [GAM], and Random Forest [RF]. Within each of these modeling algorithms performed assessments on variable inclusion and model accuracy. We used weighted input from the best models in each algorithm to create an Ensemble model that is meant to overcome assumptions shortcomings of any one algorithm (Araujo and New 2006). Habitat models were re-classified into predictions of High, Medium and Low suitability, and these classes were intersected with the ecosystems recognized within the county to give an approximate area of predicted habitat within each. These suitability classes were also intersected with areas to be conserved, those that may be impacted in future development, and those likely already disturbed to quantify the current and future status of conservation and potential impact to each species. 2 Table of Contents Executive Summary _______________________________________________________ 2 Table of Contents ________________________________________________________ 3 Introduction ____________________________________________________________ 11 Methods _______________________________________________________________ 11 Species data _________________________________________________________________ 11 Environmental covariates ______________________________________________________ 12 Quantitative statistical modelling methods _______________________________________ 15 Quantitative model interpretation ______________________________________________ 17 Ecosystem and Impact Assessments. _____________________________________________ 17 Species Accounts and Distribution Models ____________________________________ 19 ANLE ‐ Sticky Ringstem (Anulocaulis leiosolenus) ___________________________________ 19 Species Status _____________________________________________________________________ 19 Range ____________________________________________________________________________ 19 Population Trends __________________________________________________________________ 20 Distribution and Habitat Use __________________________________________________________ 20 Distribution and Habitat Use within Clark County _________________________________________ 21 Habitat Model ___________________________________________________________________ 22 General Additive Model ___________________________________________________________ 26 Maxent Model __________________________________________________________________ 27 Random Forest Model ____________________________________________________________ 28 Model Discussion ________________________________________________________________ 29 Standard Error __________________________________________________________________ 30 Ecosystem Level Threats _____________________________________________________________ 32 Threats to Species __________________________________________________________________ 33 Existing Conservation Areas/Management Actions ________________________________________ 34 Monitoring _____________________________________________________________________ 34 Management: ___________________________________________________________________ 34 Summary of Direct Impacts ___________________________________________________________ 35 ARCA ‐ Las Vegas Bearpoppy (Arctomecon californica) ______________________________ 36 Species Status _____________________________________________________________________ 36 Range ____________________________________________________________________________ 37 Population Trends __________________________________________________________________ 37 3 Habitat Model _____________________________________________________________________ 37 General Additive Model ___________________________________________________________ 41 MaxEnt Model __________________________________________________________________ 43 Random Forest Model ____________________________________________________________ 44 Model Discussion ________________________________________________________________ 45 Standard Error __________________________________________________________________ 46 Distribution and Habitat Use within Clark County _________________________________________ 48 Ecosystem Level Threats _____________________________________________________________ 49 Threats to Species __________________________________________________________________ 50 Existing Conservation Areas/Management Actions ________________________________________ 50 Summary of Direct Impacts ___________________________________________________________ 51 CHPE ‐ Desert Pocket Mouse (Chaetodipus penicillatus) _____________________________ 51 Species Status _____________________________________________________________________ 52 Range ____________________________________________________________________________ 52 Population Trends __________________________________________________________________ 52 Habitat Model _____________________________________________________________________ 52 General Additive Model ___________________________________________________________ 57 MaxEnt Model __________________________________________________________________ 58 Random Forest Model ____________________________________________________________ 59 Model Discussion ________________________________________________________________ 60 Standard Error __________________________________________________________________ 61 Distribution and Habitat Use within Clark County _________________________________________ 63 Ecosystem Level Threats _____________________________________________________________ 64 Threats to Species __________________________________________________________________ 64 Existing Conservation Areas/Management Actions ________________________________________ 65 Summary of Direct Impacts ___________________________________________________________ 65 COAM ‐ Yellow‐Billed Cuckoo (Coccyzus americanus) _______________________________ 65 Species Status _____________________________________________________________________ 66 Range ____________________________________________________________________________ 67 Population Trends __________________________________________________________________ 67 Habitat Model _____________________________________________________________________ 67 MaxEnt Model __________________________________________________________________ 72 Random Forest Model ____________________________________________________________ 73 Model Discussion ________________________________________________________________ 74 Standard Error __________________________________________________________________ 75 4 Distribution and Habitat Use within Clark County _________________________________________ 77 Ecosystem Level Threats _____________________________________________________________ 79 Threats to Species __________________________________________________________________ 79 Existing Conservation Areas/Management Actions ________________________________________ 79 Summary of Direct Impacts ___________________________________________________________ 80 COCH ‐ Gilded Flicker (Colaptes chrysoides) _______________________________________ 81 Species Status _____________________________________________________________________ 81 Range ____________________________________________________________________________ 82 Population Trends __________________________________________________________________ 82 Habitat Model _____________________________________________________________________ 82 General Additive Model ___________________________________________________________ 86 MaxEnt Model __________________________________________________________________