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1.
The hispid pocket mouse ( Chaetodipus hispidus ) occurs throughout the Great Plains, mainly west of the Missouri River. In Nebraska, this species likely occurs throughout the state, but records of occurrence were lacking for east-central and northeastern counties. During a survey in 2008 for the plains pocket mouse ( Perognathus flavescens ) in eastern Nebraska, we documented C. hispidus in 10 new counties, including a modest range expansion into northeastern Nebraska. Many individuals were captured on moderately compact soils consisting of silt, but some also were captured on sandy and other friable soils. Most individuals were captured in areas containing some exposed ground, but this may reflect our trap placement for P. flavescens. Individuals from northeastern and east-central Nebraska best resembled C. h. spilotus from southeastern Nebraska, with black coloration suffused on the dorsum, head, and dorsal side of the tail; however, our individuals generally lacked the characteristic bright ochraceous coloration along lateral lines and on the dorsum. Limited evidence supports a recent expansion in distribution within the region.  相似文献   

2.
Thirteen species of bats occur in Nebraska, but limited information is available on those inhabiting southwestern parts of the state. We investigated the distribution, abundance, and reproductive activity of bats in 5 counties in extreme southwestern Nebraska (Chase, Hays, Dundy, Hitchcock, and Red Willow). From April 2007 to April 2008, we deployed mist nets on 15 occasions at 8 localities over the Republican River and its tributaries. We captured 100 individuals representing 5 species, including the evening bat ( Nycticeius humeralis ), eastern red bat ( Lasiurus borealis ), hoary bat ( Lasiurus cinereus ), big brown bat ( Eptesicus fuscus ), and silver-haired bat ( Lasionycteris noctivagans ). All species raised young in this region of Nebraska, except L. noctivagans , which was documented only during migration. Lactating females of N. humeralis captured on 15 June and volant young captured on 23 June extend known dates of reproductive activity for this species in the state, and an adult female captured on 30 April represents the earliest seasonal record of this species from Nebraska. Our records of evening bats also extend the known distribution of this species farther west in Nebraska than previously reported. Changes in land use throughout the Great Plains during the last century have altered many habitats, such as gallery forests associated with rivers, and distributions of mammals, including bats, have shifted to reflect those ecological changes.  相似文献   

3.
Silver-haired bats ( Lasionycteris noctivagans ) were thought only to migrate through Nebraska; however, recent surveys in eastern Nebraska report summer records of females and their young. Our study in western Nebraska also shows that silver-haired bats are summer residents. We discovered the 1st reproductively active L. noctivagans in this part of the state. We caught lactating females and volant young in riparian forests along the North Platte River and in forested areas of the Pine Ridge. Previously, adult males were not known from Nebraska in summer, and only 4 records of L. noctivagans were known from western Nebraska during migration. On 28 July we captured an adult male in a coniferous forest of the Wildcat Hills, and we have more than 100 records of migrating individuals. Lastly, an obese L. noctivagans captured on 4 November may represent an individual preparing to hibernate in the state.  相似文献   

4.
We report the collection of 8 additional specimens of Sorex merriami from northwestern Nebraska; previously only 2 specimens had been collected in the state. The new specimens were captured in pitfall traps and Sherman live-traps from 1979 through 1996 in Dawes, Sheridan, and Sioux counties. These individuals were caught together with Sorex cinereus and several rodent species in a variety of grassland habitats, including disturbed roadsides dominated by native and introduced grasses and forbs, grassland openings in forests of ponderosa pine, and an open, dry grassland. Seven of the new specimens, captured in late May, early June, and December, were young-of-the-year, and 4 of these were not in reproductive condition; reproductive status of the other 3 was not assessed. One individual, captured in late May, was an old male in reproductive condition.  相似文献   

5.
In North America, Nebraska represents part of the northwestern edge of the distribution for the evening bat ( Nycticeius humeralis ). To date, little information on this bat's natural history has been published from the state or from other parts of the Great Plains. Here we report on aspects of its natural history in Nebraska from 2 localities. In late summer and early autumn of 2006, we documented individuals farther west in Nebraska (Harlan County) than previously reported and determined that individuals fed mainly on Coleoptera and Hymenoptera. In 2006, evening bats appeared to migrate from Nebraska during late September–early October, and individuals were extremely fat, about 15 g, prior to migration. Evening bats likely are more widespread and common in south central Nebraska than previously documented. On 6 October 2005, we reported on an individual from eastern Nebraska (Douglas County), which represents the latest seasonal record of N. humeralis from the state.  相似文献   

6.
Occurrences of mountain lions ( Puma concolor ) in Nebraska have been steadily increasing; however, reproductive activity in mountain lions has not been documented in the state. We present the first evidence of mountain lion reproduction in Nebraska since mountain lions recolonized the state in the early 1990s. On 28 February 2007, a spotted kitten was hit by a vehicle in northwestern Nebraska; and based on body length and weight, we estimate its age at 3.9 months. On 20 December 2008, a female mountain lion and spotted kitten were photographed in the northwestern part of the state. On 9 May 2009, a female mountain lion with a juvenile was also photographed. All records were from the Pine Ridge region of Dawes County, Nebraska. Our records suggest that mountain lions are establishing a permanent population in at least one region of Nebraska.  相似文献   

7.
The milliped genus Narceus Rafinesque, 1820 (Spirobolida: Spirobolidae) occupies parts or all of 2 Canadian provinces, Québec and Ontario; every U.S. state east of the Mississippi River; and 9 states to the west including Minnesota, Iowa, Missouri, Arkansas, Louisiana, Nebraska, Kansas, Oklahoma, and Texas. Records are detailed for the "western" states and New England and include the first from Minnesota, Connecticut, Delaware, and Maine; occurrence is projected for southeastern Minnesota and the Delmarva Peninsula. The genus presently comprises 2 valid species that are endemic to Florida— N. gordanus (Chamberlin, 1943) and N. woodruffi Causey, 1959—and 2 of uncertain status that occur throughout the generic range and are referenced as the " N. americanus/annularis complex"; geographic evidence suggests greater diversity, particularly in the south, and a 2nd generic revision is in order to update the existing one by Keeton (1960). Records cluster within a large, semicontinuous area whose northern, southern, and western range extremes, respectively, are Saint-Nicolas, Lévis Census Division, Québec; Key West, Monroe County, Florida, and northeastern Duval County and Rockport, Aransas County, Texas; and Garner State Park, Uvalde County, Texas. The eastern limit is the Atlantic Ocean, and records are available from Cape Cod and Tuckernuck Island, Massachusetts; Long Island, New York; Cape Hatteras, North Carolina; and James Island, South Carolina. The projected western boundary, based on peripheral localities, angles southwestward from Omaha, Nebraska, to Uvalde County; and the northern boundary passes through central Iowa and Wisconsin (encompassing the Door Peninsula) and the southern periphery of the Upper Peninsula of Michigan. The lone Minnesota locality, from Lyon County in the southwest, lies substantially north of the projected border in Iowa and well west of the expected area of occurrence in southeastern Minnesota. The northernmost record west of the Mississippi River, it may represent an allopatric population that extends westward into eastern South Dakota.  相似文献   

8.
New geographic, reproductive, and seasonal records are presented for 11 of 13 bats inhabiting Nebraska. New geographic records are presented for 10 species, most notably Myotis lucifugus (120 miles west of nearest known record), M. septentrionalis (42 miles west of nearest record), Nycticeius humeralis (72 miles west of nearest record), and Pipistrellus subflavus (258 miles northwest of nearest record). New reproductive localities are recorded for 9 species, particularly the 1st records of breeding by Pipistrellus subflavus in Nebraska (Cherry and Dixon Counties) and the 2nd record of breeding by Lasionycteris noctivagans in Nebraska (Lancaster County). New records of timing of lactation and appearance of flying-young are reported for 7 species, and new records of seasonal activity are reported for 3 species. Lastly, captures of adult males of Lasiurus borealis and L. cinereus in summer are reported from sites across the state; summer populations of these species previously were thought to consist entirely or primarily of adult females and young in some regions. Records presented here are the result of geographic range expansion of several species and of fieldwork conducted in previously unsampled areas.  相似文献   

9.
The milliped genus Apheloria occupies a broad area in Québec and Ontario, Canada, and the United States east of the Central Plains, lying generally north of the Gulf Coastal states. It is reported for the 1st time from New Jersey, District of Columbia, Illinois, and Kansas; and the 1st localities are recorded for Massachusetts, Connecticut, South Carolina, Georgia, Alabama, and Wisconsin. The projected distribution encompasses all or parts of the District of Columbia and 27 states, including Vermont and Delaware, where the genus has not been taken; New Hampshire and Mississippi lie outside the range. Chesapeake Bay and the Connecticut River form apparent eastern boundaries in Maryland–Virginia and New England, respectively; the Tennessee River does likewise on the south in northern Alabama. Aside from Arkansas, comparatively few records exist from the 6 projected states of occurrence west of the Mississippi River. Only 1 each is available from Iowa and Kansas, and there are no definite localities in Nebraska, where occurrence is postulated at Omaha, the type locality of Fontaria luminosa Kenyon, 1893. Confirmation with fresh material is necessary, but this name seems referrable to Apheloria and may be senior to either A. virginiensis iowa or A. v. reducta , both by Chamberlin, 1939, if 2 distinct races occur west of the Mississippi River.  相似文献   

10.
Summary

Monthly samples of the burrowing mud crab, Macrophthalmus hirtipes (Jacquinot 1853) were collected from February 1978 to April 1979 from a marine inlet, Governors Bay (43°38′S, 172°39′E) and from the Avon-Heathcote Estuary (43°33′S, 172°44′E), New Zealand. The estuarine population was generally unimodal and had an annual cycle of population change sustained by a concentrated summer recruitment. In contrast, the bay population was unimodal and bimodal at different times, and recruitment occurred thoughout the year with no clear peak. Both populations had equal sex ratios and were dominated by immature individuals (crabs?10·0 mm carapace width). Estuarine crabs were generally smaller than marine crabs.

At both sites, ovigerous females were found from late May to early March; the smallest egg-bearing female measured CW 10·0 mm at the estuary and CW 10·5 mm at the bay. Cycles of ovarian and embryological development were similar at the two localities. Three peaks of egg oviposition occurred within one breeding season and mature females were capable of producing successive broods. Fecundity was related exponentially to female carapace width and did not alter during the breeding season. Estuarine females carried more eggs than marine females of similar size. Egg volume was related to time of oviposition and eggs laid at the start of the breeding season were significantly larger than those deposited during the second half; however, estuarine eggs showed less reduction in size at this time than did marine eggs.

Estuarine sediments had higher levels of chlorophyll ‘a’, ATP, and microorganism activity and productivity than marine sediments. As M. hirtipes is a detritus feeder, the differences in food resources are believed to account for the elevated fecundity of estuarine crabs. At the bay, salinities were high with little tidal and seasonal variation, whereas in the estuary sea water was diluted significantly both daily and seasonally. The differences in salinity characteristics between the sites may be affecting larval distribution; recruitment in the estuary was concentrated to the summer and in the bay it was almost continuous.  相似文献   

11.
The eastern woodrat ( Neotoma floridana ) occurs throughout eastern and central parts of the United States. In Nebraska, 3 of 9 subspecies inhabit the state, including N. f. campestris , N. f. attwateri , and N. f. baileyi . We determined distributional limits of N. f. campestris along 2 river systems in southern Nebraska. As observed with other mammalian species in the Great Plains, we suspected that the distribution of woodrats likely had expanded, reflecting continued regulation of rivers and the concomitant increase in forests along them. We documented N. f. campestris at 7 sites in 5 counties, including a recent (since the 1960s) eastward expansion along the Republican River. We observed little movement along the Platte River. The greatest concentration of houses constructed by woodrats occurred in a shelterbelt near the Republican River; otherwise, abundances of houses tended to be greater along the Platte River. We suspect that the distribution of woodrats will continue to change in Nebraska unless breaks exist or are established in riparian forests along the Platte and Republican rivers.  相似文献   

12.
Changes in land use continue to alter habitats throughout Nebraska, and few studies have examined how such changes affect distributional limits of mammals. The distribution of Ord’s kangaroo rat ( Dipodomys ordii ) was last examined in eastern Nebraska about 4 decades ago. We examined the current eastern distributional limits of D. ordii to see whether its range had expanded, contracted, or remained constant in the state since the 1960s. Based on our study, kangaroo rats have experienced little change in distribution during recent decades. Herein, we report on data for 8 counties without prior records and a marginal range extension, as well as comment on habitat, reproduction, and taxonomic status of kangaroo rats in eastern Nebraska. Los cambios en el uso del suelo siguen modificando los hábitats a lo largo del estado de Nebraska, y pocos estudios han examinado cómo estos cambios afectan los límites de distribución de los mamíferos. La última evaluación de la distribución de la rata canguro de Ord ( Dipodomys ordii ) en el este de Nebraska se llevó a cabo hace 4 décadas. Examinamos los límites orientales actuales de la distribución de D. ordii para ver si su área de distribución se ha expandido, contraído o permanecido igual en el estado desde los años 1960. Con base en nuestra investigación, es posible decir que la distribución de las ratas canguro ha cambiado poco en décadas recientes. Aquí reportamos datos para 8 condados para los cuales no existían registros anteriores e informamos sobre una pequeña expansión de su área de distribución. También comentamos sobre el hábitat, la reproducción y la situación taxonómica de las ratas canguro en el este de Nebraska.  相似文献   

13.
In Iowa, the northern grasshopper mouse ( Onychomys leucogaster ) previously was known only from the northwestern part of the state. Herein, we report records of O. leucogaster from the 1970s and 1980s that extend its distribution into west-central and southwestern Iowa. These records may represent dispersal movements into these parts of Iowa by southward movements from populations in northwestern Iowa or they may represent eastward movements of individuals from Nebraska prior to channelization of the Missouri River.  相似文献   

14.
Emergents of Pteronarcys californica, Calineuria californica , and Hesperoperla pacifica were captured with replicated emergence traps at 3 sites along the banks of Rock Creek, Montana. Pteronarcys emergence in early June was short (88% of individuals in 6 d) and attained rates of 5 m -1 d -1 (shoreline distance) and cumulative densities up to 19 m -1 yr -1 . Calineuria emerged synchronously (89% in 9 d) 2 wk later at densities up to 7 m -1 d -1 and 40 m -1 yr -1 . The less numerous Hesperoperla (5 individual m -1 yr -1 ) had a longer emergence period partially coinciding with Calineuria Median males of Pteronarcys and Calineuria emerged 2-3 d before median females; protandry was not significant Hesperoperla . Sex ratios were female-biased in Pteronarcys and Hesperoperla but male-biased in Calineuria . Size trends through emergence were very weak although females showed a greater tendency towered larger size early in emergence.  相似文献   

15.
Scytonotus granulatus (Say, 1821) (Polydesmida: Polydesmidae), the most widely ranging polydesmid species in North America and the 4th most widely distributed indigenous continental milliped, is recorded from LeFlore and Latimer Counties, Oklahoma, and Jackson County, Alabama, the 1st records from these states. It also occurs in Logan and Independence Counties, Arkansas. The Latimer County record corresponds approximately to the terminus of the eastern forested biome and extends the distributions of the species and the genus some 255 miles (408 km) westward; along with literature records from Shawnee County, Kansas, and Cass County, Nebraska, it constitutes the western range limits. The projected overall distribution extends around 1100 miles (1760 km) east-west and 985 miles (1576 km) north-south and encompasses parts of Ontario, Québec, and 19 states, including all of Pennsylvania, West Virginia, Ohio, Indiana, and Illinois. New localities are detailed as are those from Missouri and that from Dare County, on the Outer Banks of North Carolina.  相似文献   

16.
A review of the distribution of Rhinocheilus l. lecontei, in Utah, with a northward extension of its range in the Upper Colorado River Basin.  相似文献   

17.
The Wood River sculpin Cottus leiopomus is endemic to the Wood River Basin in central Idaho and is a nongame species of concern because of its limited distribution. However, status and genetic population structure, 2 factors often central to the conservation and management of species of concern, have not been assessed for this species. We used backpack electrofishers to survey streams that were small enough (i.e., a priori to contain, possibly contain, or not contain the sculpin, respectively. Native redband trout Oncorhynchus mykiss gairdneri were present at 21 study sites, including 18 of the 20 sites that contained Wood River sculpin. Sixty-one study sites (60%) were dry or had too little water to contain any fish. We estimated that a minimum of 1.36 million Wood River sculpin (≥20 mm total length) currently reside in the basin. The presence of Wood River sculpin was positively associated with stream width:depth ratio and percent cobble/boulder substrate and negatively associated with stream gradient. Mitochondrial DNA haplotype differences were observed between and within the 3 major river subbasins supporting sculpin, with the most striking differences observed between populations in the Camas Creek subbasin and the other 2 subbasins, among which no haplotypes were shared, suggesting relatively long-term isolation. Our results suggest that the Wood River sculpin remains relatively widespread and abundant within its endemic range, despite obvious changes in historical stream connectivity caused by irrigation diversions and other chronic habitat alterations.  相似文献   

18.
Distribution, status, habitat, elevational range, original literature citations, synonymy, and specimens deposited at Brigham Young University (BRY), University of Colorado (COLO), Colorado State University (CS),Denver Botanical Garden (KHD), Kansas State University (KSC), University of Kansas (KANU), Missouri Botanical Garden (MO), and the Rocky Mountain Herbarium (RM) are given for 79 species of rare Colorado plants. Species federally listed by the U.S. Fish and Wildlife Service under the Endangered Species Act, candidates for listing, and species that qualify as federal candidates because of limited range, small populations, or known threats are included. Suggested changes in status are offered where appropriate. Maps and tables indicating the Colorado range of these species are provided.  相似文献   

19.
We determined the distribution and estimated population number of Preston White River springfish ( Crenichthys baileyi albivallis ) in summer 1998 and winter 1999. The total population was < 5000 fish persisting in only 4 of 6 spring systems from which it had been previously captured. To improve its status, we recommend conservation measures.  相似文献   

20.
In most populations of mountain goats ( Oreamnos americanus ), mineral lick use is an essential part of the ecology of the species. In many areas, the distribution and use of licks in the landscape is poorly known, rendering planning for resource development difficult. We examined lick use by 28 GPS radio-collared mountain goats in 2 study areas in southeastern British Columbia during 2004&ndash;2005. Viewing collar-location movements on digital orthophotos, we assumed goat use of 6 previously known and 10 suspected mineral licks. Field visits verified that 9 of the 10 suspected sites were mineral licks. Thirteen of the 15 licks used by collared goats were within forests with commercial harvesting potential. All but 3 of the licks were &le;600 m from the closest logging block, and 5 licks were &#60;100 m away. Number of annual visits to licks by individual goats ranged from 0 to 9. Goats often moved considerable distances (up to 17.3 km) to visit licks. Most visits by males occurred between early May and late June (median 9 June), and most visits by females occurred between early June and mid-July (median 21 June). Mean time spent at licks on each visit was 1.5 days for females and 1.6 days for males. Most of the licks were characterized by numerous cavities dug under trees (which we term &ldquo;lick trees&rdquo;). Using GPS collars, we were able to collect data on lower-elevation mineral licks not previously known to researchers.  相似文献   

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