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.     

New species of oribatids from western Colorado (Acarina: Cryptostigmata, Suctobelbidae)

A new species of Suctobelba, S. tumulata, and a new genus and species, Parisuctobelba septenia, are described from collections of oribatids taken in coal strip-mining spoil banks near Hayden, Colorado. The new species are compared with members of the family from North America and Europe. The new genus is differentiated by a smooth, narrowed sensillum and seven pairs of genital setae. Taxonomic and ecological data are also discussed.     

There is no valid record of cliff chipmunk ( Tamias dorsalis ) in the Sandia Mountains, New Mexico

In the American Southwest, the red squirrel ( Tamiasciurus hudsonicus ) occurs as disjunct populations in coniferous forests on mountaintops. There is a paucity of information concerning the species’ distribution and habitat in western New Mexico. I report new records that document and verify the occurrence of red squirrels in additional montane areas in west central New Mexico, including the Mangas Mountains, Canovas Rim, Turner Mountain, Tularosa Mountains, Elk Mountains, Bearwallow Mountain, and Pinos Altos Mountains. I also report observations of red squirrels from an atypical habitat—low-elevation riparian forests. These new records suggest that the geographic distribution of the species in west central New Mexico is broader than indicated by existing records. However, I also document the apparent extirpation of red squirrels from the Zuni Mountains in northwestern New Mexico. The red squirrel is one of several avian and mammalian species associated with mixed coniferous forests that have become extirpated in this mountain range.     

First record of a range extension of the cliff chipmunk ( Tamias dorsalis ) into the Huachuca Mountains

Chipmunks are widely distributed throughout the mountain ranges of Arizona. However, no living chipmunks are known from the Huachuca Mountains despite the availability of favorable habitat. Based upon pelage characteristics of captured individuals, we provide the first report of a breeding population of cliff chipmunks ( Tamias dorsalis ) in the Huachuca Mountains and discuss possible mechanisms of their arrival.     

Variation in the incidence of botfly larvae ( Cuterebra ) in two sympatric species of Peromyscus in northern Colorado

Differences in botfly parasitism were observed in the sympatric species Peromyscus maniculatus and P. difficilis in northern Colorado. The overall incidence of infection was 13.7 percent in P. maniculatus and only 0.6 percent in P. difficilis. The incidence of parasitism was affected markedly by trapping locality and by month of capture.     

Habitat features and predictive habitat modeling for the Colorado chipmunk in southern New Mexico

Two subspecies of Colorado chipmunk (state threatened and federal species of concern) occur in southern New MeXico: Tamias quadrivittatus australis in the Organ Mountains and T. q. oscuraensis in the Oscura Mountains. We developed a GIS model of potentially suitable habitat based on vegetation and elevation features, evaluated site classifications of the GIS model, and determined vegetation and terrain features associated with chipmunk occurrence. We compared GIS model classifications with actual vegetation and elevation features measured at 37 sites. At 60 sites we measured 18 habitat variables regarding slope, aspect, tree species, shrub species, and ground cover. We used logistic regression to analyze habitat variables associated with chipmunk presence/absence. All (100%) 37 sample sites (28 predicted suitable, 9 predicted unsuitable) were classified correctly by the GIS model regarding elevation and vegetation. For 28 sites predicted suitable by the GIS model, 18 sites (64%) appeared visually suitable based on habitat variables selected from logistic regression analyses, of which 10 sites (36%) were specifically predicted as suitable habitat via logistic regression. We detected chipmunks at 70% of sites deemed suitable via the logistic regression models. Shrub cover, tree density, plant proximity, presence of logs, and presence of rock outcrop were retained in the logistic model for the Oscura Mountains; litter, shrub cover, and grass cover were retained in the logistic model for the Organ Mountains. Evaluation of predictive models illustrates the need for multi-stage analyses to best judge performance. Microhabitat analyses indicate prospective needs for different management strategies between the subspecies. Sensitivities of each population of the Colorado chipmunk to natural and prescribed fire suggest that partial burnings of areas inhabited by Colorado chipmunks in southern New Mexico may be beneficial. These partial burnings may later help avoid a fire that could substantially reduce habitat of chipmunks over a mountain range.     

New species of Astragalus (Leguminosae) from Mesa County, Colorado

Named and described is Astragalus debequaeus Welsh from Mesa County, Colorado.         

New records and range extensions of species of Dipogon (Hymenoptera, Pompilidae) in Colorado

Four species of Dipogon are recorded from Colorado for the first time. These are hurdi Evans, pulchripennis (Cresson), graenicheri Banks, and brevis (Cresson). All are inhabitants of wooded areas and are believed to nest in cavities in trees. Notes are presented on habitat and prey of these 4 species and of the recently described species kiowa Evans.     

A new species of Penstemon (Scrophulariaceae) from the Uinta Basin of Utah and Colorado

Named as a new species is Penstemon albifluvis J. L. England. The species is known from the Uinta Basin of Utah and Colorado.     

New species and a new combination of Mentzelia section Bartonia (Loasaceae) from the Colorado Plateau

A new species, Mentzelia (sect. Bartonia ) cronquistii , subfamily Mentzelioideae, is described and a new combination, M. (sect. Bartonia ) marginata (Osterhout) is made. These two species of the Colorado Plateau are closely related to each other, but their relationships to other species in section Bartonia are obscure.     

Chironomidae (Diptera) species distribution related to environmental characteristics of the metal-polluted Arkasas River, Colorado

Mining in the Upper Arkansas catchment has polluted the river with heavy metals for 140 yr. Pupal and adult chironomid species distribution and sedimentary metal concentrations are provided for 22 stations along 259 km of main river during 1984-85. Complete species identification was achieved only recently. This has produced an unprecedented record of chironomid species distribution for a comparable length of river in the USA. Chemically or physically perturbed sites had poor species richness compared with the next site downstream, suggesting that larvae may drift through unfavorable habitats to benign ones. Using canonical correspondence analysis, we found species composition to be most strongly related to variables expressing the longitudinal axis of the river (distance/altitude, temperature, latitude), while toxicity to zinc was a significant secondary correlate. These river-related environmental variables accounted for a greater proportion of pupal species variation than for adults. This was considered to result from a proportion of adults emerging from habitats beyond the main river. Multivariate analysis identified metal-tolerant and -intolerant species. Generic data revealed the same major trends but indicator taxa were lost. The study provides a disturbed-state reference for monitoring effects of remedial actions begun in 1991, and for comparisons with other Colorado rivers.     

Two new species of Xironogiton (Clitellata: Branchiobdellida) from western North America

Xironogiton, a genus of crayfish worm (order Branchiobdellida), is historically endemic to North America. To date, six species of Xironogiton have been described, including five and one from areas west and east of the Continental Divide, respectively. Recent collections of the crayfishes Pacifastacus connectens and Pacifastacus leniusculus from the endorheic Harney Basin in south-eastern Oregon, USA, revealed the presence of two previously unknown Xironogiton species, which we describe herein. Discovery and characterisation of Xironogiton bibendumi sp. nov. and Xironogiton malheurensis sp. nov. suggests that much work remains to understand branchiobdellidan diversity in western North America, and additional targeted sampling is needed to determine intra- and interspecific variation, and thus define species limits.http://www.zoobank.org/urn:lsid:zoobank.org:pub:B24AA844-4A73-48F2-B269-7CD08DC8389A http://www.zoobank.org/urn:lsid:zoobank.org:pub:F1787846-BF04-44A6-949B-551EE3453F26     

Intraspecific larval aggression in two species of Hyperini (Coleoptera: Curculionidae)

Two unusual types of behaviour (wandering and intraspecific aggressive behaviour) have been observed when rearing larvae of two species of the tribe Hyperini. Wandering of Hypera postica in search for food was observed in L1, L2 and L3 larvae, as well as in young L4 larvae. L1 larvae also disperse in response to crowding. Wandering of L2 to young L4 instars was a response to food shortage. Wandering of late L4 larva (‘prepupa’) occurs because of searching for a place to spin the cocoon and pupate. Encounters between the larvae may result in agonistic behaviour, and some larvae may die as a consequence of fighting. This aggression increases with food limitation. Agonistic intraspecific behaviour has not been described to date in weevil’s larvae and it probably may not occur under natural conditions when there is a plenty of food and larval densities are decreased by pathogens or parasitoids.     

An Irvingtonian species of Brachylagus (Mammalia: Lagomorpha) from Porcupine Cave, Park County, Colorado

Brachylagus is currently a monotypic genus of uncertain origins and known only from Holocene and late Rancholabrean. A new species of leporid is described from the early and middle Pleistocene (Irvingtonian) deposits of Porcupine Cave, Park County, Colorado. Stratified deposits of the Pit and the Velvet Room, 2 localities within Porcupine Cave, have been dated biochronologically and paleomagnetically fro the middle Irvingtonian and early to middle Irvingtonian, respectively. Brachylagus coloradoensis sp. nov., is characterized by its conserved p3 enamel patterns which are intermediate between B. idahoensis and Hypolagus, and its size which is slightly larger than that of B. idahoensis . This suggest a possible ancestral relationship between Hypolagus and Brachylagus .     

Consumption of diffuse knapweed by two species of polyphagous grasshoppers (Orthoptera: Acrididae) in southern Idaho

Consumption of diffuse knapweed ( Centaurea diffusa Lam.) by 2 polyphagous grasshopper species, Melanoplus sanguinipes (F.) and Oedaleonotus enigma (Scudder), was studied using microhistological analysis of grasshopper crop contents. Grasshoppers were confined to cages containing C. diffusa and Sisymbrium altissimum L., a member of the mustard family known to be readily eaten by these 2 grasshopper species. Preference indices for knapweed were lower than for S. altissimum in 4 of 5 trials. An uncaged population of M. sanguinipes on a knapweed-infested site consumed only small amounts of knapweed until late summer when most other plants were senescent. Results suggested that diffuse knapweed s low palatability to generalist herbivores may confer to it a competitive advantage over other rangeland plants.     

Home-range fidelity and use of historic habitat by adult Colorado pikeminnow ( Ptychocheilus lucius ) in the White River, Colorado and Utah

Twelve wild adult Colorado pikeminnow ( Ptychocheilus lucius ), captured in the tailwaters of Taylor Draw Dam on the White River, Colorado, were implanted with radio transmitters and their movement patterns monitored from 1992 to 1994. The spawning migration of these fish was extensive. In 1993, the only full year of the study, the fish migrated an average of 658 km from the White River to spawning sites in the Yampa or Green rivers and back to the White River. Eight of these fish were translocated in the river upstream of the dam in April 1993. These fish and the 4 others below the dam remained in the river until May 1993. All 12 had migrated down the White River to spawning sites in the Green and Yampa rivers by July 1993. The fish that were located above the dam successfully passed over the dam during their downstream migration. Seven fish migrated upstream toward the Yampa River Canyon spawning site and 5 migrated downstream toward the Green River Desolation/Gray Canyon spawning site. Five of 7 Yampa River fish were found at the spawning site. The other 2 were found 5-8 km downstream of the site. One of 5 Green River fish was found at the spawning site, the other 4 between 16 and 62 km upstream of the site. All fish migrated back to the White River by August 1993 and were found near the dam by October 1993. Two fish were recaptured and translocated above the dam in September 1993. Five fish were located below the dam and 2 above the dam in April 1994. By July 1994 seven of the same fish that had migrated toward the Yampa River in 1993 were found at the Yampa Canyon spawning site. At the same time, 3 of 5 fish that migrated toward the Green River in 1993 were found at the Desolation/Gray Canyon spawning site. This included 2 fish that had been found upstream of the site in 1993. The 12 fish traveled an average of 6 km d -1 (range: 4-10 km d -1 ) during the migration period from May through October 1993. Generally, fish moved faster to the spawning site than back from the site to the White River. These fish moved very little within their home ranges in the White River. Six fish tagged in 1992 moved only 0.1-2.3 km in the tailwater reach below Taylor Draw Dam from September 1992 through April 1993. All fish, after their spawning runs, had moved up to or near the dam by October 1993. These fish were not tracked again until April 1994. Their movement patterns in April 1994 were similar to those observed in April 1993. The greatest amount of fish movement in the White River was displayed by the 8 fish placed above Taylor Draw Dam in April 1993 and the 2 placed in Kenney Reservoir in September 1993. They moved 1.1-40.6 km in the river before and after their spawning migration in spring and autumn 1993. These spawning migrations suggest that adult Colorado pikeminnow in the White River were recruited from both Green and Yampa river spawning populations and were presumably imprinted to these respective spawning sites. Those fish placed above Taylor Draw Dam established home ranges in habitats previously occupied by Colorado pikeminnow before the dam was completed. They remained there until they migrated downstream during the spawning period. Although we did not study fish passage, our study demonstrates that adult Colorado pikeminnow will use habitat if access is provided. Translocation of wild adult fish into historic but unoccupied habitats may be a valuable recovery option.     

Parasites from two species of suckers (Catostomidae) from southern Utah

Twenty Catostomus latipinnis and 50 Catostomus discobolis from La Verkin Creek and the Fremont River in southern Utah were collected and surveyed for parasites. Data from the survey indicated that 83 percent of the fish were infected with at least one parasite, with the fish from La Verkin Creek harboring more parasites. Twelve genera and 12 species of parasites were identified from these fish. A monogenetic trematode, Gyrodactylus elegans, which was found in 90 percent of the fish, was the most common parasite. Comments are included on habitat and host variations for the parasitofauna from suckers taken from the two locations.     

Sperm ultrastructure in two species of Gyraulus (Gastropoda: Pulmonata: Planorbidae)

Sperm morphology offers a rich source of potentially informative characters for gastropod taxonomy and in this study it was used to provide additional information for Gyraulus (Armiger) crista (Linnaeus, 1758), whose taxonomic position within the Planorbidae Rafinesque, 1815 remains uncertain. Sperm morphology in G. (A.) crista and G. (Gyraulus) albus (Müller, 1774), the type species of the genus, was examined using light microscopy, scanning electron microscopy and transmission electron microscopy. The ultrastructure of spermatozoa in the two species was found to conform to the general pattern characteristic of the Hygrophila Férussac, 1822: the spermatozoa had an anterior head containing an acrosomal complex (apical vesicle and acrosomal pedestal) and cone-shaped nucleus, followed by a very long midpiece with glycogen spirals, and then by a glycogen piece and tail. Although the spermatozoa of the two species shared some common features (one nuclear keel and four glycogen spirals), they differed significantly in length, morphology of the annulus and structure of the spiral surface ridges. There were also some differences in the size and structure of the acrosomal pedestal and the shape of the nucleus. The spermatozoa of the two Gyraulus species are compared with those of other Hygrophila and the possible importance of sperm morphology for the taxonomic status of G. (A.) crista is discussed.