David A. Haukos

Survival and Recovery Rates of Mottled Ducks Banded in Texas and Louisiana

SEAFWA Journal Volume 2, March 2015

The Western Gulf Coast population of the mottled duck (Anas fulvigula) is dependent on the Gulf coastal marsh to complete its entire life cycle. Band recovery data can be used to monitor mottled duck populations by estimating annual survival, indexing harvest rate, and assessing movements. Band returns from hunting seasons 1997 - 2013 were used to evaluate factors influencing annual survival, recovery rates, and movements of mottled ducks in Texas and Louisiana. For banding years of 1997 - 2013, 58,349 normal, wild mottled ducks were banded and released in Texas and Louisiana. Since 2002,...

Year
2015

Mottled Duck (Anas fulvigula) Movements in the Texas Chenier Plain Region

SEAFWA Journal Volume 2, March 2015

As a surrogate species for Strategic Habitat Conservation, the mottled duck (Anas fulgivula) is an indicator species to coastal marsh health and function. Currently, biologists have a relatively poor understanding of regional mottled duck movements. We outfitted adult female mottled ducks with solar satellite transmitters during summer 2009-2011. Movement patterns were measured among years and phenology, in relation to available habitat at the landscape level, and in association to potential disturbance. Movement distances were measured in ArcGIS and then evaluated using analysis of...

Year
2015

Duckling Survival, Fecundity, and Habitat Selection of Mottled Duck Broods on the Upper Texas Gulf Coast

SEAFWA Journal Volume 2, March 2015

Mottled ducks (Anas fulvigula) on the western Gulf Coast have exhibited a steep population decline since the mid 1990s. Low rates of breeding incidence and nest success have been implicated in this decline, but duckling survival and the habitat needs of broods have not been previously investigated in this region. We fitted mottled duck ducklings and adult females with radio transmitters and tracked broods to estimate duckling survival and brood habitat selection on the upper Texas Gulf Coast. Duckling survival to 30 days was high (range among models 0.354-0.567) compared to other dabbling...

Year
2015

Blood Lead Exposure Concentrations in Mottled Ducks (Anas fulvigula) on the Upper Texas Coast

SEAFWA Journal Volume 2, March 2015

The mottled duck (Anas fulvigula) is a non-migratory waterfowl species dependent upon coastal marsh systems, including those on the Texas Chenier Plain National Wildlife Refuge (NWR) Complex, and considered a regional indicator species of marsh habitat quality. Research from the early 1970s, 1990s, and early - 2000s indicated that mottled ducks continued to exhibit elevated wing-bone lead (Pb) concentrations, decades after implementation of non-toxic shot regulations. However, wing-bone concentrations reflect lifetime accumulation of Pb, whereas blood Pb concentrations reflect more recent...

Year
2015

Habitat Use of Female Northern Pintails in the Playa Lakes Region of Texas

Playas and other wetlands of the High Plains provide important winter and migration habitats for the continental population of northern pintail (Anas acuta). Factors hypothesized to influence habitat use by pintails in the Playa Lakes Region of Texas (PLR) include wetland type, annual rainfall, and natural and anthropogenic disturbance. We assessed patterns of habitat use for 133 and 164 radio-tagged female pintails 23 October 2002-18 February 2003 and 10 October 2003-18 February 2004, respectively, in the PLR. Birds were continuously monitored for a 24-hour period at least three times a...

Year
2008

Aerial Surveys for Prairie Grouse Leks: Detectability, Disturbance Response, and

Prairie grouse (Tympanuchus and Centrocercus spp.) once occupied wide expanses of North American grass and shrub habitats. In the last three decades, prairie grouse populations have exhibited precipitous declines, often because of altered land use practices. There is a need to develop new research and management techniques to facilitate prairie grouse conservation efforts. We evaluated aerial survey capabilities to assist in the management of lesser prairie-chickens (Tympanuchus pallidicinctus; [LPC]). Our objectives were to determine the most efficient aircraft type and flight parameters...

Year
2008

Population Characteristics of American Woodcock Wintering in Texas

Despite recent stabilization in measured indices, American woodcock (Scolopax minor) populations have demonstrated long-term population declines since 1968 as measured by the Federal Singing-Ground and Wing-Collection surveys. We quantified long-trends in annual sex and age ratios, recruitment index, and changes in body mass of 3,022 woodcock harvested in eastern Texas during winters of 1977-78 through 2002-03. The mean juvenile:adult ratio was 0.58 and none of the annual values exceeded 1.0. This ratio declined significantly over time for females. The male:female ratio for all birds also...

Year
2007

Nutrient Reserve Models for Post-breeding Lesser Prairie-chicken

We developed and evaluated 7 least-squares regression models to estimate body fat and protein reserves from external measurements of post-breeding male and female lesser prairie-chickens (Tympanuchus pallidicinctus). For males, protein was adequately modeled (R2 = 0.60), but attempts to model body fat were unsuccessful. For females useful fat (R2 = 0.92), log fat (R2 = 0.74), condition index (R2 = 0.58), and protein (R2 = 0.74) models were derived. These models can be used to compare post-breeding lesser prairie-chicken nutrient reserves among populations and habitats, without sacrificing...

Year
1989