Within-Patch Structures Influence Small Mammal Abundance in Managed Forests of Northern California, USA

2019 ◽  
Vol 65 (6) ◽  
pp. 796-804 ◽  
Author(s):  
Steven M Gray ◽  
Gary J Roloff ◽  
Andrew J Dennhardt ◽  
Brian P Dotters ◽  
Thomas T Engstrom

Abstract We evaluated how forest type, vegetation structure in trapping webs, and proximate forest types influenced localized (~6.35 hectares) abundances for commonly captured small mammals in northern California, USA. We trapped from May to August of 2011–13 in 69 forest patches that represented: (1) clearcuts (3–5 years postharvest), (2) 10–20 year-old conifer plantations, (3) rotation-aged conifer stands, and (4) Watercourse and Lake Protection Zones. We captured 11 species; four in sufficient numbers for regression modeling. Our average abundance estimates for the study were 4.57 (standard error [SE] = 0.43), 0.32 (SE = 0.11), 0.90 (SE = 0.30), and 0.25 (SE = 0.09) individuals per web location (~0.75 hectares) for Peromyscus spp., Neotoma spp., California ground squirrels, and Allen’s chipmunks. We found that web-level ground cover (shrubs and grass), downed wood, and types of forests containing our trapping webs best described small mammal abundances, whereas proximate forest types were not important. Our results indicated that retaining localized structures in the form of understory shrub cover and downed wood positively influences small mammal abundance in intensively managed forests of northern California.

1992 ◽  
Vol 8 (01) ◽  
pp. 57-71 ◽  
Author(s):  
Susan Walker ◽  
Alan Rabinowitz

ABSTRACTSmall mammal live-trapping was carried out in a dry tropical forest mosaic in Huai Kha Khaeng Wildlife Sanctuary, central Thailand. Trapping was done in two forest types in three seasons.Maxomys surijerwas the dominant species in both plots. The three most abundant species in each plot accounted for > 90% of all captures. Community structure, density, relative abundance, biomass, age structure of populations, and habitat usage of some small mammal species varied by forest type and season. The dry evergreen/mixed deciduous forest type supported a greater abundance and biomass of small mammals than the mixed deciduous/dry dipterocarp forest type in all seasons, although species richness was the same. The greatest density, biomass, and home-range size forMaxomys surijeroccurred in the rainy season in both forest types. Seasonal changes in ratios of adults and subadulls of several species suggested a breeding peak at the end of the dry season or beginning of the rainy season. The mixed deciduous/dry dipterocarp forest showed a drastic drop in numbers, density, and biomass of small mammals six weeks after a fire burned through it.


2003 ◽  
Vol 81 (1) ◽  
pp. 163-167 ◽  
Author(s):  
Jörn Theuerkauf ◽  
Sophie Rouys ◽  
Wlodzimierz Jedrzejewski

We studied wolf (Canis lupus) selection of 19 den, 10 rendezvous, and 31 resting sites found between 1986 and 2000 in the Bialowieza Forest (Poland). Our objective was to determine whether wolves selected sites far from villages, forest edges, and roads, and whether these sites had dense ground cover for concealment. We also tested whether wolves selected a particular forest type for their den sites. Den and rendezvous sites were located at greater distances from villages, forest edges, and intensively used roads than random points. Locations of resting sites were not affected by these manmade structures. Wolves selected dry coniferous forests for den sites but also used other forest types. We concluded that the suitability of an area for pup raising depended mainly on the spatial distribution of forest, human settlements, and public roads, and to a lesser extent on habitat characteristics.


Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1542
Author(s):  
Nadezhda V. Genikova ◽  
Viktor N. Mamontov ◽  
Alexander M. Kryshen ◽  
Vladimir A. Kharitonov ◽  
Sergey A. Moshnikov ◽  
...  

Bilberry spruce forests are the most widespread forest type in the European boreal zone. Limiting the clear-cuttings size leads to fragmentation of forest cover and the appearance of large areas of ecotone complexes, composed of forest (F), a transition from forest to the cut-over site under tree canopy (FE), a transition from forest to the cut-over site beyond tree canopy (CE), and the actual clear-cut site (C). Natural regeneration of woody species (spruce, birch, rowan) in the bilberry spruce stand—clear-cut ecotone complex was studied during the first decade after logging. The effects produced by the time since cutting, forest edge aspect, and the ground cover on the emergence and growth of trees and shrubs under forest canopy and openly in the clear-cut were investigated. Estimating the amount and size of different species in the regeneration showed FE and CE width to be 8 m—roughly half the height of first-story trees. Typical forest conditions (F) feature a relatively small amount of regenerating spruce and birch. The most favorable conditions for natural regeneration of spruce in the clear-cut—mature bilberry spruce stand ecotone are at the forest edge in areas of transition both towards the forest and towards the clear-cut (FE and CE). Clear-cut areas farther from the forest edge (C) offer an advantage to regenerating birch, which grows densely and actively in this area.


2021 ◽  
Vol 13 (13) ◽  
pp. 20033-20055
Author(s):  
Naveen Babu Kanda ◽  
Kurian Ayushi ◽  
Vincy K. Wilson ◽  
Narayanan Ayyappan ◽  
Narayanaswamy Parthasarathy

Documenting the biodiversity of protected areas and reserve forests is important to researchers, academicians and forest departments in their efforts to establish policies to protect regional biodiversity. Shettihalli Wildlife Sanctuary (SWS) is an important protected area located in the central Western Ghats of Karnataka state known for its diverse flora and fauna with distinct ecological features. For the last four decades the sanctuary has witnessed the loss of forest cover, yet the vegetation in few locations is relatively undisturbed. The current inventory was undertaken during 2019–2020 to provide a checklist of woody species from SWS under-researched earlier. The list comprises 269 species of trees, lianas and shrubs distributed in 207 genera and 68 families. The most diverse families are Fabaceae, Moraceae, Rubiaceae, Rutaceae, Lauraceae, Apocynaceae, Meliaceae, Malvaceae, Phyllanthaceae, and Anacardiaceae, representing 48% of total woody flora. The sanctuary shelters 263 native and six exotic plant species. Thirty-nine species were endemic to the Western Ghats, five species to peninsular India and one species to the Western Ghats and Andaman & Nicobar Islands. Four forest types, i.e., dry deciduous, moist deciduous, semi-evergreen, and evergreen forests, are represented in the sanctuary. Of the total species, only seven occurred in all forest types, while 111 species are exclusive to a single forest type. One-hundred-and-four taxa were assessed for the International Union for Conservation of Nature & Natural Resources (IUCN) Red List. Ten species that fall under Near Threatened, Vulnerable, and Endangered categories were encountered occasionally. The baseline data generated on plant diversity will be useful in highlighting the importance of these forests for species conservation and forest management. Such data form a cornerstone for further research. For instance, to understand the effect of invasive species and human impacts on the diversity of the region. 


1991 ◽  
Vol 18 (2) ◽  
pp. 125 ◽  
Author(s):  
AF Bennett ◽  
LF Lumsden ◽  
JSA Alexander ◽  
PE Duncan ◽  
PG Johnson ◽  
...  

A total of 1487 observations of nine species of arboreal mammal, Acrobates pygmaeus, Phascolarctos cinereus, Petauroides volans, Petaurus australis, P. breviceps, P. norfolcensis, Pseudocheirusperegrinus, Trichosurus caninus and T. vulpecula, were made during surveys of the vertebrate fauna of northeastern Victoria. Habitat use by each species was examined in relation to eight forest types that occur along an environmental gradient ranging from sites at high elevation with a high annual rainfall, to sites on the dry inland and riverine plains. Arboreal mammals were not evenly distributed between forest types. Three species (P. australis, P. volans and T. caninus) were mainly associated with moist tall forests; two species (P. norfolcensis and T. vulpecula) were primarily associated with drier forests and woodlands of the foothills; the remaining three species (A. pygmaeus, P. breviceps and P. peregrinus) occurred widely throughout the forests. The composition of the arboreal mammal assemblage changed along the environmental gradient, but species displayed gradual changes in abundance with forest type rather than marked discontinuities in distributional pattern. The highest overall frequencies of occurrence of arboreal mammals were in forests typically dominated by a mixture of eucalypt species. The position at first sighting of an animal, and the relative height in the forest stratum, were used to describe the micro-habitats utilised. In general, the microhabitats occupied by each species are consistent with the distribution of their known food resources.


2021 ◽  
Author(s):  
Katie L Beeles ◽  
Jordon C Tourville ◽  
Martin Dovciak

Abstract Canopy openness is an important forest characteristic related to understory light environment and productivity. Although many methods exist to estimate canopy openness, comparisons of their performance tend to focus on relatively narrow ranges of canopy conditions and forest types. To address this gap, we compared two popular approaches for estimating canopy openness, traditional spherical densiometer and modern smartphone hemispherical photography, across a large range of canopy conditions (from closed canopy to large gaps) and forest types (from low-elevation broadleaf to high-elevation conifer forests) across four states in the northeastern United States. We took 988 field canopy openness measurements (494 per instrument) and compared them across canopy conditions using linear regression and t-tests. The extensive replication allowed us to quantify differences between the methods that may otherwise go unnoticed. Relative to the densiometer, smartphone photography overestimated low canopy openness (<10%) but it underestimated higher canopy openness (>10%), regardless of forest type. Study Implications We compared two popular ways of measuring canopy openness (smartphone hemispherical photography and spherical densiometer) across a large range of forest structures encountered in the northeastern United States. We found that, when carefully applied, the traditional spherical densiometer can characterize canopy openness across diverse canopy conditions (including closed canopies) as effectively as modern smartphone canopy photography. Although smartphone photography reduced field measurement time and complexity, it was more susceptible to weather than the densiometer. Although selection of the right method depends on study objectives, we provide a calibration for these two popular methods across diverse canopies.


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