Food habits of the western whiptail lizard ( Cnemidophorus tigris ) in southeastern New Mexico

This study presents the first food habit assessment for the western whiptail lizard ( Cnemidophorus tigris ) in the shinnery oak – mesquite habitat ( Quercus havardii – Prosopis glandulosa ) of southeastern New Mexico. Short-horned grasshoppers, termites, antlions, beetles, and spiders formed the major portion of the diet during the four-year study. Discriminant analyses were used to evaluate annual, seasonal (monthly), and sexual variation. Incidental food categories were responsible for most of the annual and seasonal variation. Dominant foods varied little between months and years. Sexual variation was more evident; it may act to reduce intraspecific competition for food resources and may be associated with secondary sexual size dimorphism.         

Spring and winter records of the eastern pipistrelle ( Perimyotis subflavus ) in southeastern New Mexico

Eastern pipistrelles ( Perimyotis subflavus ) were first documented from South Dakota, western Texas, and New Mexico during recent years, suggesting that the distribution of this species is expanding westward across central parts of North America. In New Mexico, only 2 records of P. subflavus previously were known—one from summer and one from autumn. Here we report on 3 new records of P. subflavus from southeastern New Mexico, including the first 2 records from winter and the first record from spring. One individual in winter was observed hibernating in a cave in Chaves County. Our records and previous ones from autumn and summer suggest that this species is resident throughout the year in New Mexico.     

Lesser prairie-chicken nest site selection and vegetation characteristics in tebuthiuron-treated and untreated sand shinnery oak in Texas

Radiotelemetry was used to evaluate lesser prairie-chicken ( Tympanuchus pallidicinctus ) nesting response to herbicidal conversion of sand shinnery oak ( Quercus havardii ) rangeland to grassland. Hens selected nest sites in residual grasses within lightly grazed sand shinnery oak habitat with > 75% vertical screening in the first 0.33 m and 50% overhead cover.     

New synonymy and new species of American bark beetles (Coleoptera: Scolytidae), Part VII

New synonymy of American Scolytidae is proposed as follows: Coccotrypes cyperi (Beeson) ( = Thamnurgides indicus Eggers), Pityophthorus attenuatus Blackman ( = Pityophthorus pusillus Wood), Pityophthorus digestus LeConte ( = Pityophthorus aplanatus Schedl), Pseudohylesinus sericeus (Mannerheim) ( = Pseudohylesinus yasamatsui Nobuchi), Xyleborus mutabilis Schedl ( = Xyleborus meridensis Wood). New names are proposed to replace junior homonyms as follows: Pityophthorus indigus for Pityophthorus indigens Wood, 1977 (nec Wood 1976), and Xyloborus devexulus for Xyleborus devexus Wood, 1977 (nec Schedl, 1977). The following species are named as new to science: Conophthorus echinatae (Missouri), Lymantor alaskanus (Alaska), Pityophthorus delicatus (Mexico), P. rubidus (Arizona and Mexico), P. vesculus (Panama), Scolytodes comitabilis, S. crinalis, S. crinitus, S. decorus, S. genialis, S. habilis, S. libidus, S. perpussilus, S. semipunctatus (Venezuela).     

Feeding ecology of Gila boraxobius (Osteichthyes: Cyprinidae) endemic to a thermal lake in southeastern Oregon

Gila boraxobius is a dwarf species of cyprinid endemic to a thermal lake in southeastern Oregon. Despite a relatively depauperate fauna and flora in the lake, 24 food items were found in intestines of G. boraxobius. Ten of the 24 foods, including six insects, were of terrestrial origin. The relative importance of food items fluctuated seasonally. Diatoms, chironomid larvae, microcrustaceans, and dipteran adults were the primary foods during spring. In summer, diatoms decreased and terrestrial insects increased in importance. During autumn important foods were terrestrial insects, chironomid larvae, and diatoms. Diatoms and microcrustaceans increased in importance during winter. Chironomid larvae were of importance in winter, when the importance of terrestrial food items decreased substantially. Similar food habits were observed between juveniles and adults, except that adults consumed more gastropods and diatoms and juveniles consumed more copepods and terrestrial insects. Gila boraxobius feeds opportunistically with individuals commonly containing mostly one food item. Fish typically feed by picking foods from soft bottom sediments or from rocks. However, fish will feed throughout the water column or on the surface if food is abundant there. Gila boraxobius feeds throughout the day, with a peak in feeding activity just after sunset. A daily ration of 11.1 percent body weight was calculated for the species during June. A comparison of food habits among G. boraxobius and populations of G. alvordensis during the summer shows that all are opportunistic in feeding, but that G. boraxobius relies more heavily on terrestrial foods.     

Large-scale effects on bird assemblages in desert grasslands

During winter 1996–1997 and summer 1997, we surveyed birds at 26 study sites in desert grasslands of Arizona and New Mexico to determine tolerance of birds to variability in plant composition and structure. The relationship between bird abundance and vegetative characteristics might be an important consideration in the development of management and restoration plans. Of the 49 bird species we observed, we examined 13 and 16 species in detail for winter and summer seasons, respectively. A noticeable shift in species composition occurred between 3% and 10% woody plant cover. During winter, Chestnut-collared Longspurs ( Calcarius ornatus ) and Horned Larks ( Eremophila alpestris ) showed significant positive relationships with grass cover and negative relationships with woody plant cover, occurring in greatest numbers where woody cover was <1%. The richness of sparrow species during winter was highest among sites with 6% to 15% woody plant cover. In addition to showing significant positive relationships with woody cover, Vesper Sparrows ( Pooecetes gramineus ), Black-throated Sparrows ( Amphispiza bilineata ), Brewer’s Sparrows ( Spizella breweri ), and Chipping Sparrows ( S. passerina ) showed significant positive relationships with shrub species richness. Our results showed that reductions of woody plant cover below 3% in combination with the presence of native grasses could substantially enhance the presence of several bird species. Maintenance of woody cover between 6% and 15% could increase use by a suite of other species, especially wintering sparrows.     

New synonymy and new species of American bark beetles (Coleoptera: Scolytidae), Part IV

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} New synonymy is proposed as follows: Pityophthorus Eichhoff ( = Pityophthoroides Blackman), Scolytodes Ferrari ( = Ctenophorus Chapuis), Araptus pallidus (Blackman), n. comb. (? = Neodryocoetes portoricensis Schedl, Neodryocoetes devius Schedl), Corthylus letzneri (Ferrari) ( = Corthylus strigilatus Eggers, Corthylus columbianus Schedl, Corthylus ater Schedl), Corthylus spinifer Schwarz ( = Corthylus guayanensis Eggers), Hypothenemus brunneus (Hopkins) ( = Hypothenemus cryphalomorphus Schedl, Stephanoderes bituberculatus Eggers), Monarthrum parvum (Eggers) ( = Monarthrum praeclarum Wood), Phloeoborus punctatorugosus Chapuis ( = Phloeoborus breviusculus Chapuis), Phloeotribus pilula Erichson ( = Phloeotribus australis Schedl), Phloeotribus setulosus Eichhoff ( Phloeotribus dubius Eichhoff, Phloeotribus spinipennis Eggers), Pityophthorus, pulicarius (Zimmermann) ( = Pityophthorus cubensis Schedl), Pityophthorus subsimilis Schedl ( = Pityophthorus subimpressus Bright), Premnobius cavipennis Eichhoff ( = Premnobius latior Eggers), Scolytus propiguus Blandford ( = Scolytus penicillus Schedl), Xyleborus dryographus (Ratzeburg) ( = Xyleborus linearis Schedl), Xyleborus horridus Eichhoff ( = Xyleborus flohri Schedl). Xyleborus tonsus (Hagedom), n. comb., was transferred to Xyleborus from Dryocoetes. Pityophthorus aquilus Blackman and Pityophthorus cascoensis Blackman, n. status, were removed from synonymy. Scolytodes chapuisi, n. n., is proposed for Scolytodes ( = Ctenophorus ) laevigatus Chapuis, 1869 (nec Ferrari 1867). The following species are named as new to science: Araptus crassus (Panama), A. obesus (Brazil), Cnesinus prominulus (Mexico), Conophthorus conicolens (Mexico), Microcorthylus vicinus (Mexico), Pityophthorus alnicolens (Mexico), P. assitus (Mexico), P. concinnus (Mexico), P. indigens (Colorado), P. leechi (California), P. solatus (Mexico), P. speciosus (Mexico), Pseudopityophthorus denticulus (Texas), Pseudothysanoes securus (Mexico), P. turnbowi (Texas), Pycnarthrum fulgidum (Colombia), Scolytodes fulmineus (Venezuela), S. radiatus (Costa Rica), Xyleborinus tribuloides (Mexico), Xyleborus devexus (Florida, Puerto Rico), and X. laticeps (Venezuela).     

Homing in eastern fence lizards ( Sceloporus undulatus ) following short-distance translocation

We conducted an experiment on eastern fence lizards ( Sceloporus undulatus ) during August-September 1995 near Los Alamos, New Mexico, (1) to ascertain if lizards that were relocated short distances exhibited homing, (2) to investigate a possible barrier to movement, and (3) to determine the effect of translocating individuals from a transplant area on lizards in a recipient area. We relocated 15 of an estimated population of 39 (95% CI 36-45) lizards an average distance of 46 m. Fourteen of 15 translocated lizards returned to within 6.81 ( s ￣x = 1.43) m of the original capture location. Movement distances did not vary ( F = 0.76; 1,53 df; P = 0.381) between resident and translocated lizards during the pretreatment period and did not vary for resident ( F = 2.86; 1,12 df; P = 0.1166), but varied between pretreatment and posttreatment periods for translocated ( F = 14.65, 1,7 df, P 0.0065) lizards. Translocated lizards did not affect the resighting probability of resident lizards ( F = 0.96; 1,14 df; P = 0.34), but this may be related to low power (1 — β = 0.15) and translocated lizards moving out of the area quickly.     

New synonymy, new species, and taxonomic notes of North American Pityophthorus (Coleoptera: Scolytidae), Part III

New synonymies and new data affecting North American Pityophthorus are proposed as follows: chalcoensis Hopkins ( = herrerai Hopkins) and nigricans Blandford ( = chiapensi s Bright). Neotypes are designated for the following species described by Eichhoff: concentralis, cribripennis, infans, puchellus, and tuberculatus. New species are: carinatus (Canada), cavatus (Manitoba, Saskatchewan), euterpes (Mexico), hesperius (British Columbia), impexus (Mexico), intentus (Arizona), laticeps (Mexico), malleatus (Arizona), mesembria (Guatemala), montezumae (Mexico), scalptus (British Columbia, Colorado), trepidus (California), and vespertinus (Mexico).     

Food habits of clouded salamanders ( Aneides ferreus ) in Curry County, Oregon (Amphibia: Caudata: Plethodontidae)

Stomach contents of 650 clouded salamanders ( Aneides ferreus ), collected monthly throughout the year from Curry County, Oregon, were examined. Samples from three age classes were involved: (1) 489 adults, (2) 131 juveniles, and (3) 30 hatchlings. Foods did not vary by sex, but did vary by age and by season. Hatchlings ate small items, particularly mites, springtails, flies, and small beetles. Juveniles fed mainly on flies, isopods (sowbugs), beetles, mites, and centipedes in winter; beetles, ants, and isopods in spring; ants and beetles in summer; and isopods, beetles, and ants in fall. Adults ate isopods and beetles as their major foods in winter, spring, and fall and isopods, ants, beetles, and earwigs in summer. Four species were exceedingly important as foods for these salamanders: an unidentified isopod, the snout beetle ( Trachyphloeus bifoveatus ), the European earwig ( Forficula auricularia ), and an ant ( Lasius alienus ).       

Status of Thamnophis sirtalis in Chihuahua, Mexico (Reptilia: Colubridae)

This is a study of the populations of Thamnophis sirtalis that occur in Chihuahua, Mexico, and the adjoining U.S. state of New Mexico. Reference is made to previous studies dealing with geographical and systematic relationships. Additional data are provided for the New Mexico subspecies ( dorsalis ), and the relationship of T. s. parietalis to the New Mexico population is discussed. The Chihuahua population is described as a new subspecies.     

Experimental manipulations of precipitation seasonality: effects on oak ( Quercus ) seedling demography and physiology

Predicted changes in regional precipitation patterns and soil moisture caused by anthropogenic trace gas emissions may affect the distribution and abundance of woody plants in arid and semiarid regions. To test the response of woody plants to potential changes in precipitation regimes, we manipulated summer and winter precipitation on plots that contained seedlings of Quercus emoryi Torr. (Emory oak), the dominant tree in oak savannas of the southwestern United States. Throughout the growing season, we monitored seedling survival and physiology (predawn leaf water potential, midday instantaneous gas exchange, and leaf carbon isotope discrimination). Seedling survival and physiological performance differed little between treatments, which embodied 50% changes to quantities of summer and winter precipitation, and encompassed a continuum of precipitation from 359 mm · year -1 to 846 mm · year -1 . However, survival and physiological performance of seedlings were negatively impacted by seasonal environmental conditions common to all treatments, especially during the annual pre-'monsoon' drought. Seedling predawn leaf water potentials, net CO 2 assimilation, and stomatal conductance indicate that growing conditions for Q. emoryi seedlings at this site are generally restricted to periods with adequate soil moisture (i.e., April and August). Results contrast with an assumption implicit to the ""two-layer"" soil water resource partitioning hypothesis that woody plants in all life history stages are more dependent upon winter than summer precipitation. In fact, summer precipitation appears more important than winter precipitation for Q. emoryi seedling recruitment and growth.     

Black bears ( Ursus americanus ) harvest Jeffrey pine ( Pinus jeffreyi ) seeds from tree canopies

Despite much attention to the foraging habits and hibernation patterns of food-storing mammals, little is known about the contents of winter larders under natural conditions or how animals prepare a winter larder. Here we describe the contents of 15 yellow-pine chipmunk ( Tamias amoenus ) winter larders from 3 different years and describe the movement of scatter-hoarded seeds into larders. We found larders by locating 14 radio-collared chipmunks in their winter dens. One additional larder was found by tracking the movement of seeds labeled with radioactive scandium-46 from scattered caches into the larder. Chipmunks formed winter dens and rapidly provisioned winter larders in the fall, just before the onset of winter. Surface caches were dynamic, with seeds residing in 1–6 cache sites (mean = 2.6, SD = 1.1) before being found in the larder. Distances from scattered caches to the winter larder were 34.5 m (SD = 17.1). Contents of winter larders consisted of pine and shrub seeds. In 14 of the 15 larders, pine seeds contributed most to the size and caloric content of larders. Pine seeds and other seeds found in winter larders were produced by plants 2–4 months before the onset of winter. We conclude that if yellow-pine chipmunks did not scatter-hoard seeds during summer and autumn, seeds would not have been available for use in winter larders.     

Ruffed grouse ( Bonasa umbellus ) foraging in aspen stands during winter in northern Utah

Ruffed Grouse ( Bonasa umbellus ) population densities are lower in the Intermountain West than elsewhere in the species' range. Throughout much of its range, the Ruffed Grouse is closely associated with quaking aspen ( Populus tremuloides ), in part because aspen buds are an important winter food. Because population fluctuations of Ruffed Grouse have been associated with changes in aspen abundance or chemical composition, we studied winter foraging of the species in the Intermountain West where it has received little attention. Aspen buds were the most prominent forage in the bird's diet, although in contrast to other Ruffed Grouse food habits studies, reproductive buds were not eaten more than vegetative buds, and buds of other deciduous plants were also important (>20% of the diet). Excretion of high concentrations of ammonium nitrogen suggests that grouse in northern Utah are ingesting higher levels of secondary plant compounds than reported elsewhere. Our results show aspen is important in the winter ecology of Ruffed Grouse in northern Utah and suggest that continued loss of aspen may impact grouse populations.     

Factors affecting selection of winter food and roosting resources by porcupines in Utah

Ecological and phytochemical factors potentially affecting winter dietary discrimination by porcupines ( Erethizon dorsatum ) in the mountain brush zone of Utah were studied. Porcupines utilized gambel oak ( Quercus gambelii ) as their primary winter food and roosting resource. Big-tooth maple ( Acer grandidentatum ) was the most common tree species in the study area but was rarely utilized by porcupines. Conifer species were used as a food and roosting resource significantly less often than they occurred in the study area, despite thermal advantages provided by their relatively dense canopies. Oak feed trees were successfully separated from conifer feed trees by discriminant analysis 100% of the time. Oak trees were correctly classified as feed and nonfeed trees 71% of the time. Gambel oak contained higher amounts of crude protein, fiber, and tannins, but was lower in either extract fractions and fatty acid content than conifers. A layer of adipose tissue used as an energy reserve by porcupines may have relaxed energy intake demands sufficiently to permit them to concentrate on a diet of oak tissue, which is high in protein, rather than a high-fat conifer diet. A diet relatively high in protein may have facilitated digestion of food material high in fiber. Temperature did not affect selection of tree species for roosting. Rock and snow caves were utilized infrequently and the study population ranged widely. Three of 15 study animals were eaten by predators.     

Length of western tent caterpillar egg masses and diameter of their associated stems

Stems bearing egg masses of the western tent caterpillar ( Malacosoma californicum ), collected in Arizona and northern New Mexico during 1977–1980, had mean diameters between 2.9 and 4 mm. Mean lengths of the egg masses were consistently between 11 and 14 mm.     

Records of the yellow-nosed cotton rat ( Sigmodon ochrognathus ) in southwestern New Mexico

The yellow-nosed cotton rat ( Sigmodon ochrognathus ) previously was known only from extreme southwestern New Mexico in the Peloncillo and Animas mountains. Here I document S. ochrognathus at 3 localities from the Big Burro and Mogollon mountains in southwestern New Mexico. My northernmost capture represents an extra-limital record of 160 km north of prior records in southern New Mexico and represents the northernmost occurrence in North America. Lack of intensive mammalian surveys in the region render it difficult to interpret my recent captures, but the most parsimonious explanation is that captures likely represent overlooked populations. I captured S. ochrognathus in grassy areas ungrazed by domestic livestock along the Gila River. Understanding the use of limited grassland habitats along arid rivers by terrestrial vertebrates in the region is important because many of these grasslands have been converted to agricultural lands or are grazed by livestock.     

Formation and contents of yellow-pine chipmunk ( Tamias amoenus ) winter larders

Despite much attention to the foraging habits and hibernation patterns of food-storing mammals, little is known about the contents of winter larders under natural conditions or how animals prepare a winter larder. Here we describe the contents of 15 yellow-pine chipmunk ( Tamias amoenus ) winter larders from 3 different years and describe the movement of scatter-hoarded seeds into larders. We found larders by locating 14 radio-collared chipmunks in their winter dens. One additional larder was found by tracking the movement of seeds labeled with radioactive scandium-46 from scattered caches into the larder. Chipmunks formed winter dens and rapidly provisioned winter larders in the fall, just before the onset of winter. Surface caches were dynamic, with seeds residing in 1–6 cache sites (mean = 2.6, SD = 1.1) before being found in the larder. Distances from scattered caches to the winter larder were 34.5 m (SD = 17.1). Contents of winter larders consisted of pine and shrub seeds. In 14 of the 15 larders, pine seeds contributed most to the size and caloric content of larders. Pine seeds and other seeds found in winter larders were produced by plants 2–4 months before the onset of winter. We conclude that if yellow-pine chipmunks did not scatter-hoard seeds during summer and autumn, seeds would not have been available for use in winter larders.     

Mourning dove numbers on different seral communities in the Chihuahuan Desert

Mourning Doves are the most commonly hunted game bird in New Mexico based on hunter harvest data collected by New Mexico Department of Game and Fish. Research is limited on the influence of rangeland ecological condition on Mourning Dove ( Zenaida macroura ) populations in the Chihuahuan Desert of New Mexico. Mourning Dove numbers were evaluated periodically (1988-1989) on ranges in late- and mid-seral conditions in south central New Mexico based on the Dyksterhuis quantitative climax procedure. Strip transect procedures were used to estimate Mourning Dove populations. Concurrently, vegetation canopy cover was determined by line intercept. On the basis of percent cover, grasses were the most abundant group on late-seral range while shrubs dominated mid-seral range. Mourning Dove sightings did not differ ( P > 0.05) between late- and mid-seral ranges, nor did they differ ( P > 0.05) among grassland, shrubland, and shrub-grass mosaic communities. Mourning Dove populations showed seasonal differences ( P < 0.05), with numbers highest in summer and fall and lowest in winter and spring. Data from our study indicate that Chihuahuan Desert ranges in either mid- or late-seral stages provide equally suitable habitat for Mourning Doves.