Growth of juvenile American lobsters in semiopen and closed culture systems using formulated diets

Growth of juvenile American lobsters, Homarus americanus , raised in four semiopen culture systems, with daily water exchange rates ranging from 29 percent to 3.3 percent, was compared with growth in a completely closed system. Animals were fed a formulated pelleted ration, water quality factors were measured daily, and changes in concentration of nitrate, orthophosphate, and total organic carbon were monitored. Results of two 90-day trials indicate that growth increased in the system with the lower water exchange rates. Maximum growth occurred in the closed system.     

An addition to the amphibian fauna of California

A population of salamanders of the genus Ambystoma has been found at Grass Lake, Siskiyou County, in Northern California. A five - year study has established that the salamanders are reproducing successfully and may represent a relictual population of native amphibians. The Grass Lake area has a sparse human population, which may help to explain how this secretive amphibian could have escaped notice. Attempts to determine the taxonomic position of the Grass Lake salamander, through comparisons of body measurements and coloration with those of other western ambystomatids, were inconclusive. These comparisons suggest, however, a close relationship with the geographically most proximate subspecies, A.t. californiense Gray and A.t. melanostictum Baird. Grass Lake is near the midpoint of a gap area of approximately 800 km that separates these subspecies. Regardless of the origin of the population, it must now be listed as an established addition to the amphibian fauna of California.     

A new monotypic genus of chiggers and four new species of Quadraseta from Venezuela (Acari: Trombiculidae)

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;} Carebareia, n. gen., and its type - species, C. johnstoni, n. sp., are described. The genus Quadraseta Brennan, 1970, is redefined and a key to the 11 included species given. Four new species, Quadraseta tachirensis, holotype ex Akodon sp., Q. rotstieri, ex Proechimys guyannensis, Q. mirandae, holotype ex Oryzomys albigularis, and Q. falconensis, ex Sylvilagus floridanus, are described.     

Basidiomycetes that decay junipers in Arizona. II

Five additional species of wood rotting basidiomycetes on Arizona junipers are described and illustrated.   All cause a white rot of dead, fallen trees. Leptosporomyces juniperinus is proposed as a new species. Vararia fibra is reported from the United States for the first time.     

Water balance and fluid consumption in the southern grasshopper mouse, Onychomys torridus

Weight loss was rapid and fluid consumption decreased sharply when Onychomys torridus were exposed to salinities greater than 0.3 Molar. The southern grasshopper mouse is physiologically unspecialized for maintaining water balance in its xeric habitat. The southern grasshopper mouse is capable of weight maintenance on smaller daily water rations than is the northern grasshopper mouse ( Onychomys leucogaster ) . Differences in the water balance of O. torridus and O. leucogaster may influence their local distributions in areas of sympatry.     

Mushroom consumption (mycophagy) by North American cervids

Native mushrooms play an important, though often underestimated, role in deer, elk, and caribou diets in North America. Mushrooms are often noted as an unusual or anomalous food in the diets of cervids; yet they often dominate diets in the late summer and fall in forested areas of western North America and throughout the year in the southeastern U.S. Mushrooms are particularly high in protein (16-19%), phosphorus (average 0.75%), and potassium (average 2%). Also, mushroom production is generally greatest in fall. Therefore, they are a highly nutritious food in late season when other native forages may marginally meet basal nutrient requirements of ungulates.     

The anatomy and taxonomy of Vanclevea (Asteraceae)

Wood, leaf, and floral anatomy of Vanclevea stylosa is compared with that of several possibly related species in the genera Acamptopappus, Eastwoodia, Grindelia, Haplopappus, and Petradoria. Although V. stylosa was originally described as a Grindelia, it is clearly distinct from that genus. Of the taxa studied, it is most closely allied to Haplopappus salincinus and H. scopulorum. The taxonomy, morphology, and distribution of the monotypic Vanclevea are detailed, and known exsiccatae are listed.     

Habitat manipulation for reestablishment of Utah prairie dogs in Capitol Reef National Park

Utah prairie dogs were transplanted onto the site of a former colony, located in Capitol Reef National Park, Utah. Shrubs on the site were significantly taller than those found on active colonies in similar habitat located on the Awapa Plateau. Therefore, the transplant site afforded a test of the hypothesis that shrub height is a major inhibitory factor affecting occupation of sites by prairie dogs. Four sites of 5 ha each were used. Vegetation treatments — rotobeating, railing, and 2,4 - D herbicide — were carried out on three of the sites and the fourth was used as a control. Shrub height and percent cover were significantly reduced on all three treatment sites. Posttreatment effects on the vegetation showed that the greatest percent moisture of the herbage was found on the railed site, followed by the herbicide, rotobeaten, and control sites. Measurements of the visual obstructions to prairie dogs showed that the rotobeaten site had the greatest visibility, followed by the railed, herbicide, and control sites. Prior to release of prairie dogs on the study area, 200 artificial burrows per treatment were dug, using a power auger. In early summer, 1979, 200 Utah prairie dogs were live - trapped near Loa, Utah. An equal number by sex and age class were released on each treatment. In 1979 a significantly higher number of animals reestablished on the rotobeaten site. In 1980 and 1981 the rotobeaten and railed sites had significantly higher prairie dog numbers than the other sites. Reproduction occurred on both the rotobeaten and railed sites in 1980 and 1981. Results indicated that, when transplanting animals onto sites of former colonies presently overgrown with shrubs, the chances of a successful transplant could be increased by first reducing shrub height and density.