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1.
2.
《Journal of Natural History》2012,46(17-20):1227-1235
In this study we analysed the acoustic activity of Hylodes heyeri in areas of Atlantic Forest, in southern Brazil. Observations were made in November 2001 and from January to April 2002, at Estação II Instituto Agronômico do Paraná, municipality of Morretes, State of Paraná. Males displayed three different vocalizations: advertisement calls, territorial calls, and courtship calls. Temporal and spectral parameters of advertisement and territorial calls were analysed, along with call intensity. The duration of the advertisement call showed a negative correlation with air temperature, with males decreasing the duration of advertisement calls at higher temperatures. Male body size was not correlated with any of the acoustic parameters. Details on habitat use, distances to nearest vocalizing neighbour, and daily calling activity are also included.  相似文献   

3.
A four-year study of five populations has revealed influences on seed production and seedling establishment of the Southwest riparian tree Juglans major . Germination is abundant after production of large seed crops (masts), but masts are produced infrequently. Within years, germination is stimulated by summer rains, enabling seedlings to establish on riparian terraces as well as streambanks. Traits such as capacity for dormancy during summer drought allow some seedlings to survive on terraces, but abundant rainfall is essential for high rates of seedling success. Ranges of moisture tolerance vary among seeds collected from different populations, suggesting that ecotypes may exist between riparian sites with dissimilar moisture regimes. Population-based differences are associated, in part, with differences in seed size.  相似文献   

4.
《Journal of Natural History》2012,46(15):1899-1911
The advertisement calls of the following Neotropical poison frog species (Dendrobatidae) are described: Colostethus brunneus, Dendrobates imitator yurimaguensis, D. leucomelas and two populations referable to Epipedobates boulengeri. Oscillograms, audiospectrograms and measurements of vocalizations are provided. Advertisement calls of C. brunneus are similar to possible related species, while D. leucomelas vocalizations deviate from suggested phylogenetic relatives. Advertisement calls of D. imitator yurimaguensis do not differ from those of D. i. imitator ; the validity of the former is doubted. Bioacoustics provide evidence that E. boulengeri could probably comprise a complex of at least two species. Five formerly suggested call types are re-defined using measurable characters. As far as possible, the 71 dendrobatid frog species for which advertisement calls have been described are allocated.  相似文献   

5.
Mortality of spruce in mixed conifer stands moderately to heavily infested with western spruce dwarf mistletoe was two to five times greater than in healthy stands in the White Mountains, Arizona. Ten-year volume growth loss for heavily infected spruce trees ranged from 25% to 40%. Estimates of growth loss for spruce on a stand basis ranged from 10% to 20% in heavily infested stands. Because western spruce dwarf mistletoe is prevalent in the White Mountains and causes increased mortality and reduced growth, its control should be included in management of mixed conifer stands there.  相似文献   

6.
An investigation of the avifauna of Mt. Dellenbaugh, Arizona, and nearby areas on the Shivwits Plateau was conducted during fall 1974 and during spring and summer 1975. A total of 92 species of birds was recorded, of which 56 were considered resident. Species composition is discussed in relation to habitat.  相似文献   

7.
《Journal of Natural History》2012,46(47-48):2929-2940
Breeding behaviour of the Omei tree frog, Rhacophorus omeimontis, was studied during the egg-laying period (mid-April to late June) in south-west China. The operational sex ratio of the breeding population was male-biased at 3.0?±?0.8 (mean?±?SD) on a nightly basis in Pond A and 4.3?±?1.1 in Pond B. Pairs with a male clasping a female occurred in ponds first; the amplectant pairs moved to a neighbouring plant and then released foam in leaves 14–370 cm above the pond's water surface. Immediately, other males came to join the pair, forming an amplexing group of 2 to 7 males (for all 45 breeding units observed). Among the males no direct physical competition for possession of the females was observed. Females produced foam which surrounded the subsequently-laid eggs. The whole process of oviposition lasted 45–65 minutes. After ovipositing, males left the female, the female folded and lined neighbouring leaves with more foam produced to surround the eggs further. This process took 15–45 minutes. The numbers of eggs in a clutch ranged from 457 to 837 and eggs were between 2.9 and 3.4 mm in diameter; those two measures were negatively correlated with each other. Eggs hatched after 12–17 days; the larval period lasted 63–78 days. Fertilization success was positively related to the number of males participating in matings.  相似文献   

8.
Late Quaternary-age arthropods were recovered from dry cave deposits and packrat middens located in the Grand Canyon, Canyonlands, and Glen Canyon region of the Colorado Plateau. This Quaternary data resource has not been analyzed before from the Colorado Plateau national parks. Radiocarbon dates on the various deposits containing arthropods range from 1510 to 30,660 yr B.P. The fossil assemblages yielded 57 identified taxa of insects, arachnids, and millipedes, including 15 taxa taken to the species level. The information from the fossil insect record of the Colorado Plateau is not yet sufficiently detailed to permit precise paleoenvironmental reconstructions. However, preliminary conclusions suggest a cooler, moister climatic regime during the late Wisconsin glacial and a mosaic of vegetation types, such as grassland and shrubby communities, unlike the present vegetation at the localities.  相似文献   

9.
《Journal of Natural History》2012,46(27-28):1729-1741
We describe the spatial pattern of variation in body size and sexual size dimorphism in the giant spiny frog, Paa spinosa (David, 1875). The study also aims to identify potential factors responsible for geographic morphological variation in the frog. The results indicate that primary production, which positively correlates with precipitation and summer temperature in China, had an important effect on body size of P. spinosa, whereas Bergmann's rule was more efficient to explain the influence of average minimum temperature in January. The species was sexually dimorphic for body size and body shape: the body size, jaw length and forelimb length of males were significantly larger than those of females. Furthermore, the degree of sexual size dimorphism varied geographically, but the relationship between the geographic variation of sexual size dimorphism and the climate was complex. Specifically, absolute sexual size dimorphism was positively correlated with the increased ambient temperature and decreased precipitation.  相似文献   

10.
The relative incidence of mistletoes found in pinyon-juniper woodlands is estimated for the Coconino National Forest, Arizona, using a roadside survey. Approximately 50% of the pinyon-juniper woodlands surveyed were infested with juniper mistletoes ( Phoradendron juniperinum or P. capitellatum ). In contrast, only about 12% of the areas surveyed were infested with pinyon dwarf mistletoe ( Arceuthobium divaricatum ). In these infested woodlands, 70% with juniper mistletoes and 44% with pinyon dwarf mistletoe were lightly infested. Most areas where pinyon dwarf mistletoe populations were observed (90%) also had juniper mistletoe ( P. juniperinum ) present, but many juniper mistletoe populations observed had no pinyon dwarf mistletoe (50%), although pinyon pine was common at those locations. Therefore, pinyon dwarf mistletoe is frequently co-distributed with juniper mistletoe as has been suggested by other investigators, but juniper mistletoe frequently occurs where there is no pinyon dwarf mistletoe present.  相似文献   

11.
We investigated ecology of flannelmouth sucker ( Catostomus latipinnis ) from 1992 to 1997 in the 26-km Lee's Ferry reach of the Colorado River immediately below Glen Canyon Dam, Arizona. We captured by electrofishing a total of 212 fish and recaptured 52 previously tagged by others. Flannelmouth sucker were captured throughout the tailwater but tended to aggregate about 5 km of the dam, possibly reflecting blockage of historic migration routes. Catch per hour of electrofishing did not differ among years but was greater from November to February than other periods, suggesting seasonal movements of flannelmouth sucker into the tailwater: Mean lengths and weights of fish did not differ among years or seasons. Length frequency analyses also indicated there were no significantly yearly trends in proportion of catch within size classes of fish. Mean condition differed only among seasons and was greatest in February, lowest in August, coinciding respectively with pre- and post-spawning periods of flannelmouth sucker in tributary just down from Lee's Ferry. Recaptured fish migrated from initial tagging locations 1.4-23.1 km downstream from Lee's Ferry. Fifty-nine percent of recaptured fish with known initial tagging locations increased in length, and fish tagged initially as subadults or adults, respectively, grew an average of 45.9 mm and 5.5 mm per year.  相似文献   

12.
The grass spider ( Agelena naevia ), commonly found in Organ Pipe Cactus National Monument, Arizona, uses rodent burrows located under a shrub canopy more frequently for web construction than burrows located in the open. The average number of prey available in canopy microhabitat was greater than in open microhabitat, and unequal prey abundance may explain spider microhabitat use.     相似文献   

13.
Nonnative rainbow trout ( Oncorhynchus mykiss ) are stocked into several reservoirs in the range of federally threatened Little Colorado spinedace ( Lepidomeda vittata ), and so have the opportunity to negatively impact Little Colorado spinedace populations. We examined rainbow trout escapement from Nelson Reservior into Nutrioso Creek, critical habitat for L. vittata . We also examined movements of L. vittata and incidence of predation by rainbow trout on L. vittata . We detected no movement of rainbow trout out of Nelson Reservoir over 4 years of study. Lepidomeda vittata marked in 3 streams did not move much; but sample sizes were too small to make any meaningful conclusions regarding movement. Most L. vittata we captured during surveys subsequent to marking were unmarked, suggesting movement out of the study area, low tag retention, mortality, or failure to capture marked fish. Lepidomeda vittata co-occurred with O. mykiss , Salmo trutta , and Salvelinus fontinalis and were typically less than half the size of the sympatric nonnative salmonids. Consequently, they are potential prey fish for these species. We found fish remains in stomachs of 33% of S. trutta , 6% of O. mykiss and 25% of S. fontinalis examined, but remains of L. vittata were found only in a single S. trutta . Because S. fontinalis are rare in the streams examined, they probably do not pose a great threat to L. vittata . Salmo trutta , which are no longer stocked, had the highest piscivory level and may thus pose more of a threat to L. vittata than O. mykiss .  相似文献   

14.
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;} A substantially complete compilation of producer-consumer biomass was achieved for two montane forest reference stands on the Arizona Mogollon Plateau. This compilation, containing published and previously unpublished data, shows these ponderosa-pine-dominated stands to be near the lower end of the biomass range of commercial forest types. The two stands averaged approximately 75 metric tons/ha of plant biomass. Consumers made up less than 0.01 percent of the forest biomass. About 9/10 of the measured consumer biomass consisted of domestic and native ruminants.  相似文献   

15.
《Journal of Natural History》2012,46(9):1023-1046
Six new species of Nematoplana are described from eastern Australia. They are distinguished on the basis of the morphology of sclerotized structures, chromosome number and morphology, and pigmentation. Six further unguiphorid species were only found immature, and cannot be formally described. They none the less have distinct morphological and/or karyological features. The Unguiphora as a whole, and the genus Nematoplana in particular, are species-rich in eastern Australia. The high diversity of the group appears due both to narrow-range endemics, and to the narrow ecological niche of many of the species.  相似文献   

16.
Small mammals play key ecological roles in grassland ecosystems, yet little is known regarding small mammal communities in large (>50 km 2 ), high-elevation prairies embedded in ponderosa pine ( Pinus ponderosa ) forests in north central Arizona. To provide information on community composition and habitat relationships, we live-trapped small mammals on 6 transects in 2 prairies in 2008. We captured 78 individuals in 5501 trap occasions. Capture rates were low and varied widely among transects. Community composition was simple, with only 3 species of small mammals captured. In order of relative abundance, these species were deer mouse ( Peromyscus maniculatus, n = 44 individuals), Mogollon vole ( Microtus mogollonensis, n = 22), and spotted ground squirrel ( Spermophilus spilosoma, n = 12). Deer mice were captured on all transects and voles on all but one transect. In contrast, spotted ground squirrels were captured on only 2 transects and were relatively common on only one transect. There were no previous records of spotted ground squirrels in these prairies. Deer mice were positively associated with rock cover and vegetation height. Voles were positively associated with shrub cover and combined cover of live and dead vegetation and were negatively associated with bare ground. Spotted ground squirrels were positively associated with forb cover. This study provides baseline data on small mammal communities in these prairies and documents the presence of a previously unknown species. Further studies would be desirable to better understand spatial and temporal variation in these communities, habitat relationships, and effects of land-use practices on small mammals and their habitats. Los mamíferos pequeños desempeñan papeles clave en los ecosistemas de pradera; sin embargo, se conoce poco con respecto a las comunidades de pequeños mamíferos en las grandes (>50 km 2 ) praderas altas, rodeadas por bosques de pino ponderosa ( Pinus ponderosa ) en la parte norte central de Arizona. Para proporcionar información sobre la composición de las comunidades y sus relaciones con el hábitat, colocamos trampas para pequeños mamíferos vivos en 2008 en 6 transectos en 2 praderas. Capturamos 78 individuos en 5501 ocasiones de trampeo. Las tasas de captura fueron generalmente bajas y variaron ampliamente entre transectos. La composición de las comunidades fue simple, con tan solo 3 especies de mamíferos pequeños capturados. Éstas fueron, en orden de abundancia relativa, el ratón ciervo ( Peromyscus maniculatus, n = 44), el metorito Mogollon ( Microtus mogollonensis, n = 22) y la ardilla moteada de tierra ( Spermophilus spilosoma, n = 12). Los ratones ciervo fueron capturados en todos los transectos y los metoritos en todos, menos uno. En contraste, las ardillas moteadas de tierra fueron capturadas sólo en 2 transectos y fueron relativamente comunes en sólo uno. No había registros anteriores de ardillas moteadas de tierra en estas praderas. Los ratones ciervo estuvieron asociados positivamente con la rocosidad y la altura de vegetación. Los metoritos estuvieron asociados positivamente con la cobertura de arbustos y la cobertura combinada de vegetación viva y muerta, y asociados negativamente con el suelo desnudo. Las ardillas moteadas de tierra estuvieron asociadas positivamente con la cobertura de maleza. Este estudio proporciona datos de referencia sobre las comunidades de pequeños mamíferos en estas praderas, y documenta la presencia de una especie previamente desconocida. Sería conveniente llevar a cabo estudios adicionales para entender mejor la variación espacial y temporal en estas comunidades, sus relaciones con el hábitat y los efectos de prácticas del uso del suelo en equeños mamíferos y sus hábitats.  相似文献   

17.
Examination of gastrointestinal tracts of native cyprinids from the Little Colorado River (LCR) in Grand Canyon, Arizona, 1990-1994, revealed varying rates of prevalence and infrapopulation levels of Asian tapeworm ( Bothriocephalus acheilognathi ). Mean prevalence was 28% (range 0-78%) in humpback chub ( Gila cypha ) and 8% (range 0-46%) in speckled dace ( Rhinichthys osculus ), with infrapopulations as high as 46 and 28, respectively. We also note Asian tapeworm infection of nonnatives common carp ( Cyprinus carpio ), fathead minnow ( Pimephales promelas ), and plains killifish ( Fundulus zebrinus ) from the LCR. Reported pathogenic and chronic effects of this cestode to its definitive hosts add concern for the status of the Grand Canyon population of the federally endangered humpback chub. The rapidity which Asian tapeworm has spread to different drainages of the Colorado River Basin likely portends an eventual cosmopolitan basin distribution in lower elevations suitable to the parasite's thermophilic life history. Such biotic changes must be considered among the most serious threats to conservation and recovery of native fish populations.  相似文献   

18.
I quantified seed production and ovule losses for Ceanothus fendleri Gray (Fendler ceanothus) plants protected from large ungulate herbivores in a ponderosa pine ( Pinus ponderosa [Laws]) forest of northern Arizona. I also tested seed germination responses to cold stratification and heat treatments in the laboratory. Fruit production on fecund stems ranged from 7.4 to 38.2 fruits per stem, which equated to 22.2-118.2 potential seeds based on 3 ovules per fruit. Stems that produced fruit were significantly large relative to their expected sizes. Predispersal ovule losses ranged from 70.7% to 91.4% across the 2 years studied. A chalcidoid seed parasite ( Eurytoma squamosa Bugbee) consumed 11%-28% of the total number of seeds produced. Postdispersal seed predation varied from 0% to 24% and was significantly affected by forest floor substrate in 1 study year. Cumulative ovule losses were estimated to be 71%-92%. Cold stratification did not significantly affect seed germination, and exposure to 90°C resulted in the highest germination percentage. Both dormant and nondormant seeds suggested a bet-hedging life history strategy. This study provides basic ecological information important for management of ponderosa pine forest and nursery production of C. fendleri .  相似文献   

19.
Discovery of a small isolated population of the white fir dwarf mistletoe, Arceuthobium abietinum f. sp. concoloris, in the Chiricahua Mountains of southeastern Arizona extends the southern distribution of this mistletoe 300 miles. The rare occurrence of the mistletoe in the southwest suggests that it once had a more southerly distribution but only survived past climatic changes in a few locations.  相似文献   

20.
Vegetation patterns in Navajo National Monument, Arizona, were studied over a five-year period from 1977 to 1981. Twelve distinct plant community types occur within the boundaries of the park. These communities are characterized and the dominant plant species of each are recorded. The relationships of parent material, soils, and moisture to plant communities are also discussed. It appears that discrete communities occupy soils of different characteristics, particularly with respect to amount of weathering of parent material.      相似文献   

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