scholarly journals Structural Characteristics of Forest Stands Within Home Ranges of Mexican Spotted Owls in Arizona and New Mexico

2003 ◽  
Vol 18 (3) ◽  
pp. 189-198 ◽  
Author(s):  
Joseph L. Ganey ◽  
William M. Block ◽  
Steven H. Ackers
Keyword(s):  
New Mexico ◽  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Structural Characteristics ◽  
Home Range Size ◽  
Home Ranges ◽  
Conifer Forest ◽  
Forest Stands ◽  
Spotted Owls ◽  
Mexican Spotted Owls

Abstract As part of a set of studies evaluating home-range size and habitat use of radio-marked Mexican spotted owls (Strix occidentalis lucida), we sampled structural characteristics of forest stands within owl home ranges on two study areas in Arizona and New Mexico. Study areas were dominated by ponderosa pine (Pinus ponderosa)–Gambel oak (Quercus gambelii) forest (Arizona) or mixed-conifer forest (New Mexico). We describe structural characteristics of forest stands used by spotted owls for both foraging and roosting, in terms of central tendencies and variability in structural characteristics among stands. Our results indicated that stands used for foraging were more variable than stands used for roosting. Observed distributions of structural variables were consistent with recommendations in the recovery plan governing management of owl habitat with a few potentially important exceptions. We also provide additional recommendations for application in forest management, based both on observed data and on extensive collective experience with the owl and its habitat. West. J. Appl. For. 18(3):189–198.

Seasonal changes in home ranges of Abert's squirrels: impact of mating season

2006 ◽  
Vol 84 (3) ◽  
pp. 404-411 ◽  
Author(s):  
A J Edelman ◽  
J L Koprowski
Keyword(s):  
Home Range ◽  
Ponderosa Pine ◽  
Home Range Size ◽  
Range Size ◽  
Home Ranges ◽  
Conifer Forest ◽  
Mating Season ◽  
Mixed Conifer ◽  
Mixed Conifer Forest ◽  
Range Overlap

We compared home ranges of introduced Abert's squirrels (Sciurus aberti Woodhouse, 1853) in mixed-conifer forests of Arizona during non-mating and mating seasons. Because Abert's squirrels are reported to depend on ponderosa pine (Pinus ponderosa P. & C. Lawson) forests, the mixed-conifer forest in our study represented a novel habitat. Home-range size, home-range overlap with females, and movement distances increased for males from non-mating to mating seasons. Home-range size and overlap characteristics of females remained consistent between seasons, but movement distances were reduced during the mating season. Males probably increased home-range size, home-range overlap with females, and movement distances during the mating season to maximize contact with scarce females. Home-range size and overlap characteristics of female Abert's squirrels likely remained stable between seasons because females do not search for mates. Restricted movements by females during the mating season may be due to changes in resource use in preparation for reproduction. Non-mating season home ranges in our study were smaller than home ranges observed in ponderosa pine forest. Abert's squirrels in mixed-conifer forest may have small home ranges because resource quality is higher than in ponderosa pine forest or competition for space with co-occurring Mount Graham red squirrels (Tamiasciurus hudsonicus grahamensis (J.A. Allen, 1894)).

Development of the mixed conifer forest in northern New Mexico and its relationship to Holocene environmental change

2008 ◽  
Vol 69 (2) ◽  
pp. 263-275 ◽  
Author(s):  
R. Scott Anderson ◽  
Renata B. Jass ◽  
Jaime L. Toney ◽  
Craig D. Allen ◽  
Luz M. Cisneros-Dozal ◽  
...  
Keyword(s):  
New Mexico ◽  
Pinus Ponderosa ◽  
Late Glacial ◽  
Conifer Forest ◽  
Lake Levels ◽  
Mixed Conifer ◽  
The Holocene ◽  
Groundwater Levels ◽  
Mixed Conifer Forest ◽  
Jemez Mountains

Chihuahueños Bog (2925 m) in the Jemez Mountains of northern New Mexico contains one of the few records of late-glacial and postglacial development of the mixed conifer forest in southwestern North America. The Chihuahueños Bog record extends to over 15,000 cal yr BP. AnArtemisiasteppe, then an openPiceawoodland grew around a small pond until ca. 11,700 cal yr BP whenPinus ponderosabecame established. C/N ratios,δ13C andδ15N values indicate both terrestrial and aquatic organic matter was incorporated into the sediment. Higher percentages of aquatic algae and elevated C/N ratios indicate higher lake levels at the opening of the Holocene, but a wetland developed subsequently as climate warmed. From ca. 8500 to 6400 cal yr BP the pond desiccated in what must have been the driest period of the Holocene there. C/N ratios declined to their lowest Holocene levels, indicating intense decomposition in the sediment. Wetter conditions returned after 6400 cal yr BP, with conversion of the site to a sedge bog as groundwater levels rose. Higher charcoal influx rates after 6400 cal yr BP probably result from greater biomass production rates. Only minor shifts in the overstory species occurred during the Holocene, suggesting that mixed conifer forest dominated throughout the record.

scholarly journals Trends in Snag Populations in Drought-Stressed Mixed-Conifer and Ponderosa Pine Forests (1997–2007)

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Joseph L. Ganey ◽  
Scott C. Vojta
Keyword(s):  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Tree Mortality ◽  
Management Practices ◽  
Pine Forests ◽  
Conifer Forest ◽  
Mixed Conifer ◽  
Ecological Processes ◽  
Ponderosa Pine Forests ◽  
Class Composition

Snags provide important biological legacies, resources for numerous species of native wildlife, and contribute to decay dynamics and ecological processes in forested ecosystems. We monitored trends in snag populations from 1997 to 2007 in drought-stressed mixed-conifer and ponderosa pine (Pinus ponderosaDougl.exLaws) forests, northern Arizona. Median snag density increased by 75 and 90% in mixed-conifer and ponderosa pine forests, respectively, over this time period. Increased snag density was driven primarily by a large pulse in drought-mediated tree mortality from 2002 to 2007, following a smaller pulse from 1997 to 2002. Decay-class composition and size-class composition of snag populations changed in both forest types, and species composition changed in mixed-conifer forest. Increases in snag abundance may benefit some species of native wildlife in the short-term by providing increased foraging and nesting resources, but these increases may be unsustainable in the long term. Observed changes in snag recruitment and fall rates during the study illustrate the difficulty involved in modeling dynamics of those populations in an era of climate change and changing land management practices.

scholarly journals Home Range Attributes and Habitat Selection of Barred Owls and Spotted Owls in an Area of Sympatry

The Condor ◽  
2007 ◽  
Vol 109 (4) ◽  
pp. 750-768 ◽  
Author(s):  
Thomas E. Hamer ◽  
Eric D. Forsman ◽  
Elizabeth M. Glenn
Keyword(s):  
Habitat Selection ◽  
Home Range ◽  
Breeding Season ◽  
Home Range Size ◽  
Negative Slope ◽  
Home Ranges ◽  
Strix Varia ◽  
Spotted Owls ◽  
Barred Owls ◽  
Selection Of

Abstract We compared home range areas and habitat selection of radio-marked Spotted Owls (Strix occidentalis) and Barred Owls (Strix varia) in an area of sympatry in the northern Cascade Range of Washington in 1986–1989. On average, home ranges of Spotted Owls were 3–4 times larger than ranges of Barred Owls, and there was little overlap of home ranges during the breeding season. Ranges of both species tended to expand during winter. Home range size of both species was negatively correlated with the amount of old forest, but the negative slope of the regression was much steeper for Spotted Owls than for Barred Owls. For both species, home ranges of individual owls typically had high overlap among seasons and years, indicating high site fidelity. Barred Owls generally occupied home ranges at lower elevations than Spotted Owls (mean  =  386 ± 27 m vs. 750 ± 68 m). Both species tended to use old forests more than expected, but Spotted Owls tended to use other cover types less than expected, whereas Barred Owls used most other cover types in proportion to their availability. We suggest that Spotted Owls may use larger ranges than Barred Owls because they prey selectively on a few species of nocturnal mammals, whereas Barred Owls forage more evenly across a broad range of prey types, including diurnal and aquatic species. The low overlap of Barred Owl and Spotted Owl home ranges suggests that territorial Barred Owls exclude Spotted Owls from their territories, at least during the breeding season, thus reducing the amount of habitat available to Spotted Owls.

Seasonal fire effects on mixed-conifer forest structure and ponderosa pine resin properties

2006 ◽  
Vol 36 (1) ◽  
pp. 238-254 ◽  
Author(s):  
Daniel DB Perrakis ◽  
James K Agee
Keyword(s):  
Pinus Ponderosa ◽  
Forest Structure ◽  
Ponderosa Pine ◽  
Bark Beetles ◽  
Conifer Forest ◽  
Mixed Conifer ◽  
Pine Resin ◽  
Ponderosa Pine Forests ◽  
Fuel Loads ◽  
Resin Defenses

This study examined the effects of spring and fall restoration burning in an old-growth mixed-conifer – ponderosa pine (Pinus ponderosa Dougl. ex P. & C. Laws.) forest in southern Oregon. Variables measured include fuel loads, forest structure indices, mortality of large ponderosa pines, and pine resin defenses. One year after treatment, reductions in surface fuel loads and changes to forest structure parameters suggested that burning treatments could meet restoration objectives, with fall burns being somewhat more effective than spring burns. However, mortality of pre settlement pines was significantly higher in fall burns than in spring burns, and both were higher than in unburned controls. Bark beetles (Coleoptera: Scolytidae) were important mortality agents within 2 years after burning. Resin defenses (pressure and flow) were variable over the 2 years of postburn study but showed no evidence of decrease in burned trees; rather, resin defenses were significantly higher in burned trees than in controls at several measurement dates. While increased beetle attacks have previously been documented following burning, there has been much less research on resin responses to fire. These findings suggest that current models of beetle–host interactions do not properly explain the effects of prescribed fire in ponderosa pine forests.

Nesting habitat of Mexican spotted owls in the Sacramento Mountains, New Mexico

2013 ◽  
Vol 77 (7) ◽  
pp. 1426-1435 ◽  
Author(s):  
Joseph L. Ganey ◽  
Darrell L. Apprill ◽  
Todd A. Rawlinson ◽  
Sean C. Kyle ◽  
Ryan S. Jonnes ◽  
...  
Keyword(s):  
New Mexico ◽  
Nesting Habitat ◽  
Sacramento Mountains ◽  
Spotted Owls ◽  
Mexican Spotted Owls
Sign in / Sign up

Export Citation Format

Share Document