scholarly journals An annotated vascular flora and floristic analysis of the southern half of the Nature Conservancy Davis Mountains Preserve, Jeff Davis County, Texas, U.S.A.

2017 ◽  
Vol 11 (2) ◽  
pp. 563-618
Author(s):  
Jeffrey James Keeling

The Nature Conservancy Davis Mountains Preserve (DMP) is located 40 km northwest of Fort Davis, Texas, in the northeastern region of the Chihuahuan Desert and consists of some of the most complex topography of the Davis Mountains, including their summit, Mount Livermore, at 8378 ft (2554 m). The cool, temperate, "sky island" ecosystem caters to the requirements that are needed to accommodate a wide range of unique diversity, endemism, and vegetation patterns, including desert grasslands and montane savannahs. The current study began in May of 2011 and aimed to catalogue the entire vascular flora of the 18,360 acres of Nature Conservancy property south of Highway 118 and directly surrounding Mount Livermore. Previous botanical investigations are presented, as well as biogeographic relationships of the flora. The numbers from herbaria searches and from the recent field collections combine to a total of 2,153 voucher specimens, representing 483 species and infraspecies, 287 genera, and 87 families. The best-represented families are Asteraceae (89 species, 18.4% of the total flora), Poaceae (76 species, 15.7% of the total flora), and Fabaceae (21 species, 4.3% of the total flora). The current study represents a 25.44% increase in vouchered specimens and a 9.7% increase in known species from the study area’s 18,360 acres and describes four endemic and fourteen non-native species (four invasive) on the property. The subsequent analysis of the results, compared to those of previous regional-flora catalogues, presents the flora of the DMP as one that is unique to the higher elevations and igneous substrates of western Texas and the northern Chihuahuan Desert. Multiple influences from overlapping and neighboring ecoregions, including the Great Plains, Madrean, and Sonoran provinces, are all seen to have varying degrees of authority in regards to the shaping of the modern-day vegetation.

Zootaxa ◽  
2017 ◽  
Vol 4352 (1) ◽  
pp. 1 ◽  
Author(s):  
JASON GIBBS ◽  
JOHN S. ASCHER ◽  
MOLLY G. RIGHTMYER ◽  
RUFUS ISAACS

The state of Michigan occupies an area between the Great Plains and the northeastern United States, bordering four Great Lakes, with diverse biogeographical regions. Michigan also has the second most diverse agriculture in the country, with many crops that depend on bees for pollination. This unique combination provides a wide range of opportunities for bees to persist, yet there is no current published checklist of these important insects. This study was conducted to provide the first annotated checklist of the bee (Apoidea: Anthophila) fauna of Michigan, summarizing aspects of their taxonomy and behavior and to provide provisional conservation assessment. The list was compiled from a critical review of published literature, museum specimens, and database records, supplemented by new collections. In total, 465 species are included in the checklist, including 38 new records, however evidence for 13 species is poor, several more species require taxonomic revision, and the presence of additional species is expected. The exotic megachilid species Megachile apicalis Spinola, M. pusilla Pérez (=concinna Smith, auct.) and Osmia taurus Smith are reported from Michigan for the first time. New state records of native species include Anthidium tenuiflorae Cockerell and Nomada alpha alpha Cockerell, both previously undocumented from eastern North America, and Nomada sphaerogaster Cockerell, which has rarely been recognized. The taxonomy of some bee species is clarified by the formal publication of 11 new synonymies (some previously reported online or in manuscripts). The following list cites junior synonyms first followed by the valid name: Andrena chippewaensis Mitchell 1960 = A. (Simandrena) wheeleri Graenicher 1904; Osmia hendersoni Cockerell 1907 = O. (Melanosmia) tarsata Provancher 1888; Osmia michiganensis Mitchell 1962 = O. (M.) subarctica Cockerell 1912 (new status, removed from synonymy with O. (M.) tersula Cockerell 1912); Sphecodes persimilis Lovell and Cockerell 1907 = S. davisii Robertson 1897; Sphecodes knetschi Cockerell 1898 = S. dichrous Smith 1853; Sphecodes carolinus Mitchell 1956 = S. coronus Mitchell 1956; Sphecodes stygius Robertson 1893 = S. mandibularis Cresson 1872; Sphecodes prostygius Mitchell 1960 = S. fattigi Mitchell 1956; Stelis vernalis Mitchell 1962 = S. coarctatus Crawford 1916; and Stelis michiganensis Mitchell 1962 = S. foederalis Smith 1854. Poorly known Andrena (Cnemidandrena) are discussed, including A. parnassiae Cockerell, a new state record, A. robervalensis Mitchell, and the extralimital A. runcinatae Cockerell. Of these, only A. robervalensis was considered in the subgeneric revision, but we recognize all three as valid species pending further study. Nomada binotata (Robertson 1903) and N. quadrimaculata (Robertson 1903) are removed from synonymy with N. ovata (Robertson 1903), based on examination of the lectotypes. A new species, Triepeolus eliseae Rightmyer, the eastern representative of the verbesinae species group, is described. A putative undescribed species, Osmia aff. trevoris, is documented, but requires additional study for its status to be fully resolved. A rich bee fauna is documented that includes geographically-restricted species, rare and regionally-declining species, and economically-important species, providing information for ongoing conservation planning and future analysis of trends in bee populations. 


2021 ◽  
Vol 23 (5) ◽  
pp. 1563-1576 ◽  
Author(s):  
Phillip J. Haubrock ◽  
Gordon H. Copp ◽  
Iva Johović ◽  
Paride Balzani ◽  
Alberto F. Inghilesi ◽  
...  

AbstractThe North American channel catfish Ictalurus punctatus has been introduced to several locations in Europe but has received little or no scientific study despite its invasive attributes, including prolific reproduction, tolerance to a wide range of conditions, opportunistic feeding, at least partial ‘predator release’, and some evidence of environmental impacts (e.g. disease transmission). To assess the species’ potential invasiveness and the likely risks to native species and ecosystems in Europe, available literature from both North America and Europe was reviewed and used to carry out risk screenings of the species for the risk assessment areas, North and South Italy, using the Aquatic Invasiveness Screening Kit (AS-ISK), which was followed by a more detailed evaluation (for both North America and Europe) of the species’ potential impacts using the Environmental Impact Classification of Alien Taxa (EICAT) assessment protocol. The AS-ISK score indicated that channel catfish is likely to pose a high risk of being invasive in both North and South Italy, with EICAT scores indicating “Major” impacts for both North America and Europe, at high and medium confidence levels, respectively. The present results emphasise the urgent need to carry out in-depth studies on introduced populations of this species to understand better its invasive potential so as to inform management decisions on the appropriate control or eradication measures for invaded water bodies.


2014 ◽  
Vol 67 ◽  
pp. 326-326
Author(s):  
C.A. Rowe ◽  
M.G. Hill ◽  
D.P. Logan

Nysius huttoni is a native species of wheat bug which is an occasional quarantine pest on export kiwifruit Wheat bug has a wide range of host plants including wheat and brassica crops as well as many weed species The kiwifruit harvest of 2013 had a high incidence of wheat bug finds on fruit in packhouses In response an orchard survey was undertaken to identify orchard habitats used by wheat bug Twentyfive orchards where wheat bug was found during packing in 2013 were surveyed from the Te Puke area from February to March At each orchard four habitats were searched (1) ground vegetation under the kiwifruit canopy (2) the loadout zone (3) edge of the loadout zone and (4) grassland surrounding the was found in and around the loadout zone associated with weed species notably Polygonum aviculare the dominant weed species in loadout zones No wheat bug was found under the kiwifruit canopy and the remaining 4 were found in grassland This preliminary survey suggests that the risk of wheat bug infestation can be reduced considerably by keeping loadout zones free of weeds during spring and summer


Author(s):  
Robert Al-Chokhachy ◽  
Mike Lien ◽  
Bradley B. Shepard ◽  
Brett High

Climate change and non-native species are considered two of the biggest threats to native salmonids in North America. We evaluated how non-native salmonids and stream temperature and discharge were associated with Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri) distribution, abundance, and body size, to gain a more complete understanding of the existing threats to native populations. Allopatric Yellowstone cutthroat trout were distributed across a wide range of average August temperatures (3.2 to 17.7ºC), but occurrence significantly declined at colder temperatures (<10 ºC) with increasing numbers of non-natives. At warmer temperatures occurrence remained high, despite sympatry with non-natives. Yellowstone cutthroat trout relative abundance was significantly reduced with increasing abundance of non-natives, with the greatest impacts at colder temperatures. Body sizes of large Yellowstone cutthroat trout (90th percentile) significantly increased with warming temperatures and larger stream size, highlighting the importance of access to these more productive stream segments. Considering multiple population-level attributes demonstrates the complexities of how native salmonids (such as Yellowstone cutthroat trout) are likely to be affected by shifting climates.


Author(s):  
Paul Stapp ◽  
Beatrice Van Horne

At first glance, the shortgrass steppe seems to offer little in the way of habitat for mammals. The expansive rolling plains, with little topographic relief or vegetative cover, provide minimal protection from predators or the harsh weather typical of the region. The short stature of the dominant native grasses prevents the development of any significant litter layer, and although snowfall can often be significant, too little accumulates to form the subnivean habitats that support small mammal populations in forests and more productive grasslands in winter. As a consequence, ecologists have typically considered the vertebrate fauna of the shortgrass steppe to be depauperate compared with other Great Plains grasslands, a hardy collection of generalists living in sparse populations. Although this characterization may generally be accurate, it has led mammalian ecologists to overlook the fauna of the shortgrass steppe in favor of that of other grasslands. It is precisely these circumstances, however, that suggest that a long-term approach may be necessary to understand the dynamics of mammal populations here. Relatively few such studies have been completed to date, but we can use the comparative and experimental results that are available to begin to determine what factors might be important. Here we review research on mammals in the shortgrass steppe, with the goal of identifying the general patterns and processes that contribute to them. Our review is roughly divided into four parts. We begin by describing the mammal communities and their broad habitat associations in shortgrass steppe environments. We then review the history of mammal research in the region to synthesize what these studies (many unpublished) have taught us about the most important determinants of the distribution and abundance of native species. Studies of mammal\ populations in the northern shortgrass steppe have spanned nearly 40 years, and we next describe some major patterns that have emerged from studies during this period. Much of this past research focused on the role of mammals in the structure and function of shortgrass steppe ecosystems, and we revisit this issue in some detail, with special emphasis on the important and sometimes controversial role of prairie dogs and other burrowing rodents. Finally, we end by considering how humans, and especially agriculture and its related activities, affect the diversity, abundance, and persistence of resident mammal populations.


Agronomy ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 699 ◽  
Author(s):  
Steiner ◽  
Starks ◽  
Neel ◽  
Northup ◽  
Turner ◽  
...  

The Great Plains of the USA is one of largest expanses of prairie ecosystems in the world. Prairies have been extensively converted to other land uses. The remaining prairie ecosystems are important for livestock grazing and provide benefits including habitat for avian, terrestrial, and aquatic species, carbon regulation, and hydrologic function. While producers, land management agencies, and some researchers have promoted livestock management using rotational stocking for increased production efficiency and enhanced ecosystem function, scientific literature has not provided a consensus on whether rotational stocking results in increased plant biomass or animal productivity. To address this research need, we established long-term grazing research using an adaptive management framework to encompass a wide range of production and ecological interactions on native grassland pastures. This paper describes objectives, design, and implementation of the long-term study to evaluate productivity and ecological effects of beef cow–calf management and production under continuous system (CS) or rotational system (RS) on native tallgrass prairie. Findings from 2009 to 2015 indicate that plant biomass and animal productivity were similar in the two grazing management systems. There were some indicators that forage nutritive value of standing biomass and soil nutrient content were enhanced in the RS system compared with the CS, yet individual calf body weight (BW) at weaning was greater in the CS. This prepares us to engage with producers to help determine the focus for the next phase of the research.


2012 ◽  
Vol 13 (1) ◽  
pp. 47 ◽  
Author(s):  
Benny D. Bruton ◽  
Wayne W. Fish

In 2010, a foliar and stem-lesion disease was observed for the first time in Oklahoma causing moderate to severe defoliation. Using microscopic examination, the physical features of the fungus were consistent with Myrothecium roridum. There was a wide range of susceptibility among watermelon cultivars in the field indicating a moderately high level of resistance to Myrothecium leaf spot in some cultivars. In greenhouse inoculation experiments, cantaloupe, honeydew, cucumber, squash, and watermelon were all susceptible to the fungus with cantaloupe and honeydew being the most susceptible and watermelon the most resistant. Furthermore, greenhouse inoculations supported the field observations as differential resistance was exhibited among the watermelon cultivars as well as the cucurbit types. Although cantaloupe was most susceptible to the foliar phase of this disease, watermelon was most susceptible to the fruit-rot phase. Natural infection of watermelon fruit has never been reported. Accepted for publication 15 December 2011. Published 30 January 2012.


1964 ◽  
Vol 42 (5) ◽  
pp. 547-601 ◽  
Author(s):  
Wray M. Bowden

A cytotaxonomic treatment is given for 12 native species, 2 introduced species, and 3 natural interspecific hybrids of the genus Elymus L. that occur in Canada. Five of the native Elymus species and an additional natural interspecific hybrid are found in Alaska. Eleven of the native species, one introduced species, and two of the natural interspecific hybrids are present in the mainland United States. Some additional native species and natural interspecific hybrids of Elymus from the mainland United States are treated briefly.Nomenclatural proposals include: Elymusglaucus Buckl. var. virescens (Piper) Bowden; E. ×uclueletensis Bowden (E. mollis Trin. f. mollis × E. glaucus Buckl. var. glaucus); E. × aleuticus Hultén (pro sp.) (E. mollis Trin. f. mollis × E. hirsutus Presl); E. canadensis L. var. wiegandii (Fern.) Bowden f. wiegandii and f. calvescens (Fern.) Bowden; E. ×maltei Bowden nm. maltei, nm. simulans Bowden, nm. churchii Bowden, and nm. brownii Bowden (E. virginicus L. × E. canadensis L.); E. virginicus L. var. jenkinsii Bowden; E. hystrix L. var. bigelovianus (Fern.) Bowden; E.piperi Bowden; E. innovatus Beal subsp. innovatus var. glabratus Bowden; and E. triticoides Buckl. var. pacificus (Gould) Bowden. Hystrixpatula Moench is here treated as Elymushystrix L.Voucher specimens are cited for the following chromosome number determinations:(1) diploid, 2n = 14: Elymusjunceus.(2) tetraploid, 2n = 28: Elymus canadensis var. canadensis, E. canadensis var. wiegandii f. wiegandii, E. diversiglumis, E. glaucus var. glaucus, E. glaucus var. virescens, E. hirsutus, E, hystrix var. hystrix, E. hystrix var. bigelovianus, E. innovatus subsp. innovatus var. innovatus, E. × maltei nm. maltei, E. riparius, E. sibiricus, E. villosus f. villosus, E. virginicus var. virginicus f. virginicus, and E. virginicus var. submuticus.Earlier literature reports (based on voucher specimens) are given for the following:(1) tetraploid, 2n = 28: Elymus mollis (two subsp. and three forms), E. piperi, and E. × vancouverensis nm. crescentianus.(2) hexaploid, 2n = 42: Elymus × vancouverensis nm. vancouverensis, and E. × vancouverensis nm. californicus.(3) octoploid, 2n = 56: Elymus arenarius, E. innovatus subsp. velutinus, and E. piperi.


1996 ◽  
Vol 23 (3) ◽  
pp. 305 ◽  
Author(s):  
M Lampo ◽  
P Bayliss

The cane toad (Bufo marinus) has received considerable attention because of its rapid spread in Australia and the potential threat it may represent to native species. Although the introduction of pathogens from native populations is now being considered to control this species, population estimates based on comparable methods that demonstrate that native populations are in fact less dense than the introduced ones are not available. Accurate population estimates are necessary to evaluate potential techniques for the control of the cane toad. We estimated population densities of cane toads over a wide range of habitat types and climate conditions by means of mark-recapture data. The capture history and location of toads each night were analysed to explore the validity of some of the assumptions of mark-recapture models. Because migrations, deaths and recruitment over three nights appear to be unimportant, populations may be legitimately regarded as closed for that period. However, cane toads seem highly sensitive to disturbance effects due to trapping andlor handling. Consequently, density estimates based on removal methods seem the most reliable because they are not sensitive to handling and trapping effects. Similarly, analyses of residuals of regressions between 1-night counts and density estimates suggested that toad nightly activity is affected by the air temperature during sampling. However, only 60% of the variation in estimated densities can be predicted by 1-night counts and air temperature. Estimates of population density over a wide range of habitats in South America were one order of magnitude lower than estimates in Australia. We speculate on the possible factors that may account for the lower densities in populations in the native range of the species.


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