Kenneth G. Boykin

Piñon–Juniper Woodland Use by Cattle in Relation to Weather and Animal Reproductive State

Abstract We conducted a study to determine the role of piñon–juniper (PJ) woodland in providing shelter for cattle at a site in central New Mexico. Positions of 16 cows, 8 pregnant or nursing (PN) and 8 nonpregnant–nonlactating (NPNL), grazing a PJ woodland–grass steppe mosaic were recorded every 5 min by Global Positioning System during late winter and early spring in 2004 and 2005 (eight different cows in each year). Hourly weather variables were also recorded at a weather station located at our research site. Weekly fecal samples were collected from all collared cattle (n = 16) to determine botanical composition of diets. Decreasing air temperatures, increasing relative humidity, winds out of the northwest (all of which are associated with heat loss), and increasing short-term thermal stress were associated with a detectable (P ≤ 0.05) increase in PJ-woodland preference of PN and NPNL cows. Days to/from calving date was a significant predictor of PJ-woodland preference of PN cows (P ≤ 0.05), which showed highest PJ-woodland preference on the day before or immediately after calving date. Preference for PJ woodland by all cows, averaged across the study period, increased with the increasing proportion of days with cold short-term thermal stress (P < 0.01) and decreasing availability of open shortgrass forage (P < 0.01). PN and NPNL cows exhibited detectably different grazing patterns (P = 0.01). PN cows explored smaller areas (P < 0.01) and traveled shorter distances (P = 0.053) than NPNL counterparts in any given day. Winterfat (Krascheninnikova lanata [Pursh] A. Meeuse & Smit) was the only plant species analyzed that was detectably more abundant (P = 0.05) in NPNL vs. PN diets, particularly during the week surrounding calving in 2005. Our data suggest that PJ woodland with abundant understory can play an important role in providing shelter for nursing or dry cattle during winter, particularly in years when forage availability is scarce.

Multispectral and Texture Feature Application in Image-Object Analysis of Summer Vegetation in Eastern Tajikistan Pamirs

We tested the Moment Distance Index (MDI) in combination with texture features for the summer vegetation mapping in the eastern Pamir Mountains, Tajikistan using the 2014 Landsat OLI (Operational Land Imager) image. The five major classes identified were sparse vegetation, medium-dense vegetation, dense vegetation, barren land, and water bodies. By utilizing object features in a random forest (RF) classifier, the overall classification accuracy of the land cover maps were 92% using a set of variables including texture features and MDI, and 84% using a set of variables including texture but without MDI. A decrease of the Kappa statistics, from 0.89 to 0.79, was observed when MDI was removed from the set of predictor variables. McNemar’s test showed that the increase in the classification accuracy due to the addition of MDI was statistically significant (p < 0.05). The proposed method provides an effective way of discriminating sparse vegetation from barren land in an arid environment, such as the Pamir Mountains.

Biodiversity losses and conservation trade-offs: assessing future urban growth scenarios for a North American trade corridor

The Sonoran Desert and Apache Highlands ecoregions of North America are areas of exceptionally high plant and vertebrate biodiversity. However, much of the vertebrate biodiversity is supported by only a few vegetation types with limited distributions, some of which are increasingly threatened by changing land uses. We assessed the impacts of two future urban growth scenarios on biodiversity in a binational watershed in Arizona, USA and Sonora, Mexico. We quantified and mapped terrestrial vertebrate species richness using Wildlife Habitat Relation models and validated the results with data from National Park Service (NPS) biological inventories. Future urban growth, based on historical trends, was projected to the year 2050 for (1) a ‘Current Trends’ (CT) scenario and (2) a ‘Megalopolis’ (MEGA) scenario that represented a transnational growth corridor with open-space conservation attributes. Based on CT, 45% of existing riparian woodland (267 of 451species) and 34% of semi-desert grasslands (215 of 451 species) will be lost, whereas in the MEGA scenario, these types would decline by 44% and 24%, respectively. Outcomes of the two models suggest a trade-off at the taxonomic class level: CT would reduce and fragment mammal and herpetofauna habitat, while MEGA would result in loss of avian-rich riparian habitat.

Monitoring Heifer Grazing Distribution at the Valles Caldera National Preserve

Monitoring Heifer Grazing Distribution at the Valles Caldera National Preserve DOI:10.2458/azu_rangelands_v30i6_cibils

Isolation and characterization of eight novel microsatellite loci in endangered Wyoming toad, Bufo baxteri

Wyoming toad (Bufo baxteri) is an endangered amphibian native to the Laramie Basin, Wyoming, USA. A captive breeding program propagates B. baxteri, and the monitoring of genetic diversity in captive stock can assist in guiding restoration and recovery efforts. We developed eight species-specific polymorphic loci from an enriched microsatellite library. For 281 samples, B. baxteri exhibited 2–11 alleles per locus, and observed and expected heterozygosities per locus ranged from 0.411 to 0.943 and from 0.400 to 0.691, respectively. Four loci deviated significantly from Hardy–Weinberg equilibrium. The eight microsatellite markers may be useful for conservation, population, and quantitative genetics for B. baxteri and closely related species.

Evaluating Biodiversity Metric Response to Forecasted Land Use Change in the Northern Rio Grande Basin

The effects of future land use change on arid and semi-arid watersheds in the American Southwest have important management implications. Seamless, national-scale land-use-change scenarios for developed land were acquired from the US Environmental Protection Agency Integrated Climate and Land Use Scenarios (lCLUS) project and extracted to fit the Northern Rio Grande River Basin, New Mexico relative to projections of housing density for the period from 2000 through 2100. Habitat models developed from the Southwest Regional Gap Analysis Project were invoked to examine changes in wildlife habitat and biodiversity metrics using five ICLUS scenarios. The scenarios represent a US Census base-case and four modifications that were consistent with the different assumptions underlying the A1, A2, B1, and B2 Intergovernmental Panel on Climate Change global greenhouse gas emission storylines. Habitat models for terrestrial vertebrate species were used to derive metrics reflecting ecosystem services or biodiversity aspects valued by humans that could be quantified and mapped. Example metrics included total terrestrial vertebrate species richness, bird species richness, threatened and endangered species, and harvestable species (e.g., waterfowl, big game). Overall, the defined scenarios indicated that the housing density and extent of developed lands will increase throughout the century with a resultant decrease in area for all species richness categories. The A2 Scenario, in general, showed greatest effect on area by species richness category. The integration of the land use scenarios with biodiversity metrics derived from deductive habitat models may prove to be an important tool for decision makers involved in impact assessments and adaptive planning processes.

Habitat assessment of Marco Polo sheep (Ovis ammon polii) in Eastern Tajikistan: Modeling the effects of climate change

Abstract Identifying the factors predicting the high‐elevation suitable habitats of Central Asian argali wild sheep and how these suitable habitats are affected by the changing climate regimes could help address conservation and management efforts and identify future critical habitat for the species in eastern Tajikistan. This study used environmental niche models (ENMs) to map and compare potential present and future distributions of suitable environmental conditions for Marco Polo argali. Argali occurrence points were collected during field surveys conducted from 2009 to 2016. Our models showed that terrain ruggedness and annual mean temperature had strong correlations on argali distribution. We then used two greenhouse gas concentration trajectories (RCP 4.5 and RCP 8.5) for two future time periods (2050 and 2070) to model the impacts of climate change on Marco Polo argali habitat. Results indicated a decline of suitable habitat with majority of losses observed at lower elevations (3,300–4,300 m). Models that considered all variables (climatic and nonclimatic) predicted losses of present suitable areas of 60.6% (6,928 km2) and 63.2% (7,219 km2) by 2050 and 2070, respectively. Results also showed averaged habitat gains of 46.2% (6,106 km2) at much higher elevations (4,500–6,900 m) and that elevational shifts of habitat use could occur in the future. Our results could provide information for conservation planning for this near threatened species in the region.