Stephen J. DeMaso

Vegetation Response to Timing of Discing to Manage Northern Bobwhite Habitat in Texas

Discing is commonly recommended to improve northern bobwhite (Colinus virginianus) habitat. However, little information exists regarding optimal timing of discing or the duration of discing effects on semiarid rangelands. Our objectives were to evaluate vegetation response to autumn (October 2003), winter (January 2004), and spring (March 2004) discing in two ecoregions of Texas (Rio Grande Plains and Rolling Plains). Our study design was a completely randomized, two-factor (treatment and soil texture) factorial with repeated measures. We collected data on percent bare ground, forb...

Three Year Post Treatment Effects of Habitat Management on a Wintering Grassland-bird Community in South Texas

Ecologically sound habitat management will be essential to reverse the current decline of grassland birds. The objective of this study is to evaluate the effects of two habitat management practices: (1) summer prescribed fire [SF], (2) a combined treatment of roller chopper, summer prescribed fire, and chemical application [CT], and (3) an open grassland [C] as “control” on wintering grassland-shrub bird community composition and abundance. Line transects of variable lengths were used to assess the bird community structure. Grassland bird species richness during first season was 31 and 15...

Overwinter Survival of Northern Bobwhites on Non-hunted Areas in Texas

As part of an ongoing investigation of sustainable harvest strategies for northern bobwhite (Colinus virginianus) populations, we are estimating overwinter survival in two Texas ecoregions that have stable bobwhite population trends, the Rolling Plains and the Rio Grande Plains. Estimating overwinter survival in the absence of hunting is an important variable in developing a sustained-yield harvest strategy for bobwhites. Overwinter bobwhite survival was estimated using radio-marked bobwhites from 16 November 2007 to 29 February 2008. Overwinter survival estimates were calculated using...

Microhabitat Structure of Winter Turkey Roosts in South Texas

We located 18 Rio Grande wild turkey (Meleagris gallopavo intermedia; RGWT) winter roost sites and 18 random sites at three study areas in Brooks and Kennedy Counties from December 2006 to February 2008. Our objective was to determine microhabitat structural characteristics of RGWT winter roosts that distinguished them from random locations in south Texas. At each roost, we measured tree height, diameter at breast height (dbh), canopy cover, and tree density. Variables were tested for normality using a Kolmogorov-Smirnov test. A t-test was used to examine differences between roost and...

Detectability of Rio Grande Wild Turkeys in South Texas

Detection estimates of Rio Grande wild turkey (Meleagris gallopavo intermedia, RGWT) are lacking and little research has focused on the development and evaluation of survey techniques for estimating RGWT populations. The objective of this study was to compare RGWT detection rates using aerial (Cessna 152) and roadside surveys in different vegetation communities in south Texas. Decoy flocks were randomly set 0-100 m from roads prior to surveys. Detection rate was estimated as (n decoys observed/n decoys available) x 100. Surveys were conducted in February and March 2007 and in November and...

Density Dependence, Harvest, and Population Dynamics in New World Quail: Implications for Harvest Theory in Upland Gamebird Management

Long-term population declines and conservation concerns resulting from large scale habitat loss have brought into question the biological justification of fixed, liberal harvest regulations as they apply to new world quail (Odontophoridae). As available quail habitat declines, biologically justifiable and sustainable methods of harvest will become essential components of quail management. Two hypotheses, the doomed-surplus hypothesis and the additive mortality hypothesis, attempt to provide a conceptual framework regarding the nature of mortality in hunted populations (i.e., compensatory...

Cover Selection by Northern Bobwhites and Hunters on a Public-hunting Area

Strength of the correlation between cover selection indices for hunters and quarry may provide information for improving hunter satisfaction and managing hunting pressure. Using radiotelemetry, we studied northern bobwhite (Colinus virginianus) cover selection on the Packsaddle Wildlife Management Area in western Oklahoma, during Oct-Feb periods beginning in 1991-92 and extending through 2001-02. Hunter locations were recorded by Global Position System (GPS) units for the 2004-05 and 2005-06 hunting seasons to determine hunter cover selection. Avoidance, neutral use, or selection of cover...

Evaluation of Survey Techniques for Wild Turkey in the Southern Great Plains

Few studies have assessed methods of estimating abundance, density, and trends of wild turkey (Meleagris gallopavo) populations and most wild turkey survey efforts have been unstandardized, unsuccessful, or limited to small scales. However, successful large-scale monitoring programs are important to management decisions and evaluating management activities. Our objectives were to evaluate survey techniques for wild turkey. We used inflatable turkey decoys, radio-tagged wild turkeys, and computer simulations to evaluate road surveys and aerial surveys from fixed-wing aircraft (Cessna 172)...

Cause-specific Mortality of Northern Bobwhites on an Area with Quail Feeders in Western Oklahoma

We investigated the effect of quail feeders on cause-specific mortality of 910 radio-marked northern bobwhites (Colinus virginianus). Research was conducted from 1 October 1991 through 1 October 1996 on the Packsaddle Wildlife Management Area (WMA) in western Oklahoma. Thirty-two feeders filled with milo were located near the center of every 8.1 haonthe283.3-ha(1.6km X 1.8 km) treatment area. The unfed area was 283.3 ha (1.6 km X 1.8 km). Treatments were separated by a 194.3-ha (1.2 km X 1.8 km) buffer area. Four-hundred-seventy-seven mortalities occurred on the control treatment and 433...

Recovery Rates of Banded vs. Radiomarked Northern Bobwhites in Western Oklahoma

We estimated interval (Dec-Feb) recovery and survival rates of marked northern bobwhites (Colinus virginianus) to determine effects of radiomarking and supplemental feeding on the Packsaddle Wildlife Management Area (WMA) in western Oklahoma from 1991 to 1996. We also estimated unretrieved harvest (crippling loss) reported by hunters and compared it to unretrieved harvest of radiomarked bobwhites to determined accuracy of hunter information. We banded 308 and radiomarked 296 bobwhites. Interval survival and recovery rates were estimated using the computer program MARK. Recovery rates of...