Energetics of the American Kestrel (Falco Sparverius) During Three Seasons in Northern Utah

Behavioral activiti es and predatory behavior of 18 American Kestrels (Falco sparverius, 9 males and 9 females) were observed for 350+ hours during 3 seasons (nonbreeding = Jan-Feb , breeding = mid-~lar-Apr, and postbreeding = late-Aug-Sept) in northern Utah. Daily energy expenditure (DEE) of male and female kestrels was estimated with a model that incorporated flight activity data from free-living birds and laboratory measurements on daytime and nighttime metabolic rates and energy costs of tissue production derived from captive kestrels. Production costs were included in the DEE for breeding and postbreeding kestrels. The energy cost of gonadal growth for males (0.02 kcal/day) and females (0.20 kcal/day) was added to the DEE of breeding kestrels. Breeding females expended an estimated 10.13 kcal/day for producing an average clutch of 4.5 eggs. The energy costs of fat deposition (2.27 and 4.39 kcal / day for males and females, respectively) and molt (2.38 and 2.72 kcal/day for males and females , respectively) were added to the DEE of postbreeding kestrels. In addition to the DEE , the model predicted nonflight energy expenditure (NFEE) and flight energy expenditure (FEE) during the day, and energy expenditure during the night (NEE). DEE of nonbreeding birds is generally higher (47.71 kcal/day) than those from the breeding (44.89 kcal / day) and postbreeding (42.42 kcal / day) seasons. DEE of females (48.69 kcal/day) is higher than males (41.31 kcal/day) primarily because females averaged 15.5% heavier than males during all 3 seasons, and females have higher costs of production. Kestrels are heaviest during the nonbreeding season and the amount of metabolizable energy available is highest. DEE is lower during the breeding and postbreeding seasons because thermoregulatory demands have decreased which may allow energy to be metabolized for production. NFEE accounts for most (48.5%) of the DEE. Flight costs are relatively small because kestrels allocate an average 3% of the photoperiod (25.6 min/day) to flight activities. Egg production accounts for 20% of the DEE of breeding females. The energy cost of fat deposition and molt accounts for 11.6 and 15.9% of the DEE for postbreeding males and females, respectively. These reproductive and tissue production costs may also elevate the DEE of breeding and postbreeding females to that of nonbreeding females

Depth-shifting cores incompletely recovered from the upper oceanic crust, IODP Hole 1256D

Author Posting. © American Geophysical Union, 2008. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry Geophysics Geosystems 9 (2008): Q08O11, doi:10.1029/2008GC002010.Seafloor drilling operations, especially those in crustal rocks, yield incomplete recovery of drilled sections, and depths of the recovered core pieces are assigned with some uncertainty. Here we present a new depth-shifting method that is simple and rapid, requires little subjective input, and is applicable to any core-log integration problem where sufficient comparable data have been collected in both the open hole and from the recovered core. Over the depth range for which both core and log data have been collected, an automatic algorithm selected the best new depth for each piece. The criteria for determining the best depth were as follows: (1) find new depths for as many pieces as possible, and (2) minimize the difference between core density and log density. In this study, depth-shifting is applied at Integrated Ocean Drilling Program (IODP) Hole 1256D, which is our first opportunity to study a section of intact, in situ upper ocean crust drilled down to gabbro. The new depths significantly improve the agreement between an independent data set and the logging record.Funding for this research was provided by a JOI/USSSP Post-Expedition Award to L.A.G. Mick Spillane of the NOAA Center for Tsunami Research provided tide calculations using OSU TPXO6.2

Stable isotopic composition of upper oceanic crust formed at a fast spreading ridge, ODP Site 801

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94808/1/ggge303.pd

A long in situ section of the lower ocean crust: results of {ODP} Leg 176 drilling at the Southwest Indian Ridge

Ocean Drilling Program Leg 176 deepened Hole 735B in gabbroic lower ocean crust by 1 km to 1.5 km. The section has the physical properties of seismic layer 3, and a total magnetization sufficient by itself to account for the overlying lineated sea-surface magnetic anomaly. The rocks from Hole 735B are principally olivine gabbro, with evidence for two principal and many secondary intrusive events. There are innumerable late small ferrogabbro intrusions, often associated with shear zones that cross-cut the olivine gabbros. The ferrogabbros dramatically increase upward in the section. Whereas there are many small patches of ferrogabbro representing late iron- and titanium-rich melt trapped intragranularly in olivine gabbro, most late melt was redistributed prior to complete solidification by compaction and deformation. This, rather than in situ upward differentiation of a large magma body, produced the principal igneous stratigraphy. The computed bulk composition of the hole is too evolved to mass balance mid-ocean ridge basalt back to a primary magma, and there must be a significant mass of missing primitive cumulates. These could lie either below the hole or out of the section. Possibly the gabbros were emplaced by along-axis intrusion of moderately differentiated melts into the near-transform environment. Alteration occurred in three stages. High-temperature granulite- to amphibolite-facies alteration is most important, coinciding with brittle-ductile deformation beneath the ridge. Minor greenschist-facies alteration occurred under largely static conditions, likely during block uplift at the ridge transform intersection. Late post-uplift low-temperature alteration produced locally abundant smectite, often in previously unaltered areas. The most important features of the high- and low-temperature alteration are their respective associations with ductile and cataclastic deformation, and an overall decrease downhole with hydrothermal alteration generally =<5% in the bottom kilometer. Hole 735B provides evidence for a strongly heterogeneous lower ocean crust, and for the inherent interplay of deformation, alteration and igneous processes at slow-spreading ridges. It is strikingly different from gabbros sampled from fast-spreading ridges and at most well-described ophiolite complexes. We attribute this to the remarkable diversity of tectonic environments where crustal accretion occurs in the oceans and to the low probability of a section of old slow-spread crust formed near a major large-offset transform being emplaced on-land compared to sections of young crust from small ocean basins

Oceanic crust evolution : constraints from integrated core-log studies

Abstract not available

Light Requirement for Seed Germination of Payson Sedge

Payson sedge (Carex paysonis Clokey) is a dominant component of many alpine floras in the western United States. This species appears to be a highly adapted colonizer (early invader) on disturbances such as acidic mine spoils at high elevations, and its rhizomatous growth habit offers promise for revegetation of these sites. The few natural seedlings observed in the field suggest that seed germination of Payson sedge is low compared with that of other alpine colonizers, and seeding trials with this species have met with poor success. Therefore, studies were designed to determine the germination requirements of this species. The effects of 2 levels each of light (visible vs. complete darkness), temperature (constant 25 degrees C vs. variable 25/3 degrees C day/night), and seed position in soil (surface vs. buried) on germination were investigated under controlled conditions in the laboratory. The highest germination percentage (mean = 28.8%) was attained under conditions of complete darkness followed by exposure to light at variable temperatures. There were no significant differences (p<0.05) in germination levels under conditions of light coupled with variable temperature (mean = 21.3%), and complete darkness followed by light at constant temperature (mean = 22.8%). Germination levels were low (mean = 10.0%) under light at constant temperature and seeds subjected to complete darkness alone germinated poorly (mean is lesser than or equal to 1.2%). We recorded low levels of germination (mean is lesser than or equal to 2.8%) from treatments of buried seeds exposed to both light conditions and both temperature levels. A requirement for light coupled with low germination levels of buried seeds suggests that standard revegetation techniques, where seeds are buried beneath the soil surface, may be inappropriate for Payson sedge. We recommend surface seeding in the fall so that extended periods of natural snow cover will promote germination the following spring.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202