Greater sage‐grouse respond positively to intensive post‐fire restoration treatments

Habitat loss is the most prevalent threat to biodiversity in North America. One of the most threatened landscapes in the United States is the sagebrush (Artemisia spp.) ecosystem, much of which has been fragmented or converted to non‐native grasslands via the cheatgrass‐fire cycle. Like many sagebrush obligates, greater sage‐grouse (Centrocercus urophasianus) depend upon sagebrush for food and cover and are affected by changes to this ecosystem. We investigated habitat selection by 28 male greater sage‐grouse during each of 3 years after a 113,000‐ha wildfire in a sagebrush steppe ecosystem in Idaho and Oregon. During the study period, seeding and herbicide treatments were applied for habitat restoration. We evaluated sage‐grouse responses to vegetation and post‐fire restoration treatments. Throughout the 3 years post‐fire, sage‐grouse avoided areas with high exotic annual grass cover but selected strongly for recovering sagebrush and moderately strongly for perennial grasses. By the third year post‐fire, they preferred high‐density sagebrush, especially in winter when sagebrush is the primary component of the sage‐grouse diet. Sage‐grouse preferred forb habitat immediately post‐fire, especially in summer, but this selection preference was less strong in later years. They also selected areas that were intensively treated with herbicide and seeded with sagebrush, grasses, and forbs, although these responses varied with time since treatment. Wildfire can have severe consequences for sagebrush‐obligate species due to loss of large sagebrush plants used for food and for protection from predators and thermal extremes. Our results show that management efforts, including herbicide application and seeding of plants, directed at controlling exotic annual grasses after a wildfire can positively affect habitat selection by sage‐grouse.     

Movements and landscape use of Eastern Imperial Eagles Aquila heliaca in Central Asia

Capsule: We describe ecological factors associated with movements of a globally declining raptor species, the Eastern Imperial Eagle Aquila heliaca.

Aims: To describe the movements, habitat associations and resource selection of Eastern Imperial Eagles marked in Central Asia.

Methods: We used global positioning system (GPS) data sent via satellite telemetry devices deployed on Eastern Imperial Eagles captured in Kazakhstan to calculate distances travelled and to associate habitat and weather variables with eagle locations collected throughout the annual cycle. We also used resource selection models to evaluate habitat use of tracked birds during autumn migration. Separately, we used wing-tagging recovery data to broaden our understanding of wintering locations of eagles.

Results: Eagles tagged in Kazakhstan wintered in most countries on the Arabian Peninsula, as well as Iran and India. The adult eagle we tracked travelled more efficiently than did the four pre-adults. During autumn migration, telemetered eagles used a mixture of vegetation types, but during winter and summer, they primarily used bare and sparsely vegetated areas. Finally, telemetered birds used orographic updrafts to subsidize their autumn migration flight, but they relied on thermal updrafts during spring migration.

Conclusion: Our study is the first to use GPS telemetry to describe year-round movements and habitat associations of Eastern Imperial Eagles in Central Asia. Our findings provide insight into the ecology of this vulnerable raptor species that can contribute to conservation efforts on its behalf.     

Marker-assisted selection for the wide-spectrum resistance to root-knot nematodes conferred by the Ma gene from Myrobalan plum (Prunus cerasifera) in interspecific Prunus material

Prunus species express a more or less wide spectrum of resistance to root-knot nematodes (RKN) of the genus Meloidogyne. Among them, sources from Myrobalan plum (P. cerasifera) control all major and minor RKN species tested. In this outbreeding species, the clones P.2175 and P.2980 are heterozygous for the Ma single dominant gene and carry the alleles Ma1 and Ma3, respectively. Each allele confers a high-level resistance to the predominant RKN, M. arenaria, M. incognita and M. javanica and to the Florida isolate of an unknown Meloidogyne sp. which overcomes the resistance from peach and almond sources. The polymorphism of two coupling-phase SCAR markers tightly linked to Ma, SCAL19₆₉₀ and SCAFLP2₂₀₂, was evaluated within diverse diploid Prunus accessions. This material belongs to the subgenera Prunophora (Myrobalan and apricot) or Amygdalus (peach, almond and almond-peach) and includes the RKN resistance sources Nemared, Alnem 1 and GF.557. The alleles SCAL19₆₉₀ and SCAFLP2₂₀₂ were not present in three apricot cultivars (Moniqui, Luizet and Stark Early Orange) representative of the genetic diversity of this species and they segregated in an interspecific cross between P.2980 and apricot. These results suggest that apricot, reported as resistant to M. arenaria, M. incognita and M. javanica, and the Myrobalan plum might possess two different resistance systems. SCAL19₆₉₀ and SCAFLP2₂₀₂ were also absent from all tested Amygdalus material, whatever its resistance to RKN. Eight Myrobalan×Amygdalus segregating progenies including bispecific (P.2175 or P.2980×peach or almond) and trispecific (P.2175 or P.2980×almond-peach) hybrids were tested with the Florida isolate to identify individuals carrying the Ma resistance alleles. Both SCARs were then evaluated for segregation in these progenies to develop marker-assisted selection of Prunus interspecific rootstocks. SCAL19₆₉₀ and SCAFLP2₂₀₂ could be clearly detected and their tight linkage to Ma1 and Ma3 was confirmed. Consequently these SCARs appear to be powerful tools to screen for RKN resistance conferred by the Ma gene. They should also facilitate marker-assisted pyramiding of Ma with other resistance genes from the Amygdalus subgenus or from the botanically-related Armeniaca section.     

Meteorological and environmental variables affect flight behaviour and decision‐making of an obligate soaring bird,the California Condor Gymnogyps californianus

The movements of animals are limited by evolutionary constraints and ecological processes and are strongly influenced by the medium through which they travel. For flying animals, variation in atmospheric conditions is critically influential in movement. Obligate soaring birds depend on external sources of updraft more than do other flying species, as without that updraft they are unable to sustain flight for extended periods. These species are therefore good models for understanding how the environment can influence decisions about movement. We used meteorological and topographic variables to understand the environmental influences on the decision to engage in flight by obligate soaring and critically endangered California Condors Gymnogyps californianus. Condors were more likely to fly, soared at higher altitudes and flew over smoother terrain when weather conditions promoted either thermal or orographic updrafts, for example when turbulence and solar radiation were higher and when winds from the east and north were stronger. However, increased atmospheric stability, which is inconsistent with thermal development but may be associated with orographic updrafts, was correlated with a somewhat higher probability of being in flight at lower altitudes and over rougher terrain. The close and previously undescribed linkages between Condor flight and conditions that support development of thermal and orographic updrafts provide important insight into the behaviour of obligate soaring birds and into the environmental parameters that may define the currently expanding distribution of Condors within and outside the state of California.     

Patterns of human–coyote conflicts in the Denver Metropolitan Area

In many cities throughout North America, human–coyote conflicts are an emerging problem. Little research has described temporal and spatial patterns of human–coyote conflicts, although such information can be an important step in developing and optimizing management efforts. We used reports from 22 entities within the Denver Metropolitan Area (DMA) in Colorado that provided information on coyote observations (signs, sightings, and encounters) and conflicts (incidents, pet-attacks, and human-attacks). Our objectives were to 1) define, quantify, and map categories of coyote observations and conflicts, and 2) investigate temporal and spatial patterns of conflicts, particularly related to land cover types and housing density classes. We compiled 4,006 coyote reports, including 78 signs (1.9%), 3,023 sightings (75.5%), 395 encounters (9.9%), 26 incidents (0.6%), 471 pet-attacks (11.8%), and 13 human-attacks (0.3%). We found a strong seasonal pattern with reports of both observations and conflicts highest during December–March and lowest during July–September. Numbers of coyote conflicts were disproportionately greater in open space and development land cover types (in contrast to natural and agricultural land cover) and in suburban housing areas (in contrast to urban, exurban, and rural areas). Hotspots of coyote conflicts were apparent in the southern region of the DMA, possibly because coyotes had better access to development, and hence interaction with residents, via natural areas bordering urban areas; reporting bias may have also influenced this outcome. Our results will help target management efforts, particularly those focused on people (e.g., education), but also highlight the critical need for improved methods of collecting conflict information via a standardized reporting mechanism to help reduce bias. © 2012 The Wildlife Society.     

Den attendance patterns in swift foxes during pup rearing: varying degrees of parental investment within the breeding pair

Parental investment varies in mammalian species, with male care of young being more common in social and monogamous species. Monogamy is commonly observed in canid species, with both males and females, and often “helper” individuals, providing some degree of care for the young. Social units of the swift fox (Vulpes velox), a small North American canid species, usually consist of a male–female pair and occasionally helpers. The role of parental investment and behavior in swift fox society is currently poorly understood. We observed swift fox dens during the pup-rearing season in each of 2 years to evaluate attendance and frequency of visits to natal dens by adult males and females. Female foxes remained at dens longer and visited them more frequently than did male foxes. Female attendance and visitation decreased throughout the pup-rearing season as pups became older and more independent. Environmental factors, including climate and its effect on prey, appeared to contribute to differences in fox behavior between the 2 years. We observed only one fox outside of the breeding pair attending a den in each of the 2 years, both of which were males. We concluded that each of these two foxes were living within the social unit of the male–female pair as a trio, but not serving as a helper and contributing to the care of the pups. Our results increased knowledge of the ecology and behavior of the swift fox, a species of conservation concern in the Great Plains of North America.