scholarly journals Preliminary assessment of habitat characteristics of woodland caribou calving areas in the Claybelt region of Québec and Ontario, Canada

Rangifer ◽  
2003 ◽  
Vol 23 (5) ◽  
pp. 247 ◽  
Author(s):  
Émilie Lantin ◽  
Pierre Drapeau ◽  
Marcel Paré ◽  
Yves Bergeron

Woodland caribou (Rangifer tarandus caribou) require a diversity of forested habitats over large areas and may thus be particularly affected by the large-scale changes in the composition and age-class distribution of forest landscapes induced by the northern expansion of forest management. In this study we examine habitat characteristics associated to the use of calving areas by woodland caribou females and calves at different spatial scales. Thirty females were captured and collared with Argos satellite transmitters that allowed to locate 14 calving areas. Field surveys were conducted at each of these areas to measure the landscape composition of forest cover types and local vegetation characteristics that are used for both forage conditions and protection cover. At the scale of the calving area, univariate comparisons of the amount of forest cover types between sites with and without calves showed that the presence of calves was associated to mature black spruce forest with a high percent cover of terrestrial lichens. Within calving grounds, univariate comparisons showed that vegetation features like ericaceans and terrestrial lichens, that are important food resources for lactating females, were more abundant in calving areas where females were seen with a calf in mid-July than in areas where females were seen alone. The protection of the vegetation cover against predators was however similar between calving areas with or with¬out a calf. Logistic regression results also indicated that vegetation characteristics associated to forage conditions were positively associated to calf presence on calving grounds. Our results suggest that foraging conditions should be given more attention in analyses on habitat requirements of woodland caribou.

Insects ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 201
Author(s):  
Wade B. Worthen ◽  
R. Kile Fravel ◽  
Connor P. Horne

The community structure of lotic odonates (Insecta: Odonata) changes downstream, but it is difficult to untangle natural and anthropogenic causes. We surveyed larvae and adults at 15 sites along the Reedy River in Greenville Co., SC, USA, from sites in forested suburban landscapes through the urban core of the city of Greenville. We used principal component analyses and Akaike information criteria models to describe the relationships between larval and adult community descriptors (abundance, richness, and diversity) and habitat characteristics at several spatial scales, including water chemistry, sediment and detritus, aquatic and streamside vegetation, and the percent cover of landforms in the surrounding landscape. At all scales, larval abundance, richness, and diversity correlated with the amount of detritus. At a small scale, adult indices correlated with the amount of sunlight and streamside vegetation. Zygopteran community composition was nested at a large scale; richness and diversity did not correlate with changes in the landscape but increased downstream. Anisopteran composition was also nested, but richness correlated with the percent cover of field, wetland, and open water in the habitat and was unrelated to downstream site position. Landscape transformation affected anisopterans more than zygopterans by opening habitats that facilitate these generalist heliotherms.


2011 ◽  
Vol 87 (05) ◽  
pp. 612-624 ◽  
Author(s):  
Eric Alvarez ◽  
Louis Bélanger ◽  
Louis Archambault ◽  
Frédéric Raulier

Pre-industrial forest cover portrait is a recognized method for establishing the bases of sustainable forest management. However, it is a spatially and temporally dependant concept that should be used with caution in presence of big fires. The objective of the study was to portray the pre-industrial landscape in a mixedwood temperate forest in central Quebec at different spatial scales. The study was based on archival records from a forest company. The pre-industrial forest cover landscape of our study area was mainly composed of mature or old-growth (>100 years) stands and dominated by mixedwood forest stands with intolerant hardwoods. The main tree species were white birch, black spruce and jack pine, three species associated to forest succession after fire in the boreal forest. Considering the great variability caused by the fires and partial knowledge of this variability, for each spatial scale considered, we propose some management targets based on the main pre-industrial characteristics of this forest. To respect the pre-industrial variability, our study suggested that silviculture should be adapted at different landscape scales. Cover types and age class targets should be based on main preindustrial characteristics at each landscape scale analyzed.


2020 ◽  
Author(s):  
Heiko Wittmer ◽  
B McLellan ◽  
R Serrouya ◽  
C Apps

Large-scale habitat loss is frequently identified with loss of biodiversity, but examples of the direct effect of habitat alterations on changes in vital rates remain rare. Quantifying and understanding the relationship between habitat composition and changes in vital rates, however, is essential for the development of effective conservation strategies. It has been suggested that the decline of woodland caribou Rangifer tarandus caribou populations in North America is precipitated by timber harvesting that creates landscapes of early seral forests. Such habitat changes have altered the predator-prey system resulting in asymmetric predation, where predators are maintained by alternative prey (i.e. apparent competition). However, a direct link between habitat condition and caribou population declines has not been documented. We estimated survival probabilities for the threatened arboreal lichen-feeding ecotype of woodland caribou in British Columbia, Canada, at two different spatial scales. At the broader scale, observed variation in adult female survival rates among 10 distinct populations (range = 0.67-0.93) was best explained by variation in the amount of early seral stands within population ranges and population density. At the finer scale, home ranges of caribou killed by predators had lower proportions of old forest and more mid-aged forest as compared with multi-annual home ranges where caribou were alive. These results are consistent with predictions from the apparent competition hypothesis and quantify direct fitness consequences for caribou following habitat alterations. We conclude that apparent competition can cause rapid population declines and even extinction where changes in species composition occur following large scale habitat change. © 2007 The Authors. Journal compilation © 2007 British Ecological Society.


2010 ◽  
Vol 86 (3) ◽  
pp. 354-364 ◽  
Author(s):  
Henrik Hartmann ◽  
Gaëtan Daoust ◽  
Brigitte Bigué

Terrestrial biodiversity is closely linked to forest ecosystems but anthropogenic reductions in forest cover and changes in forest structure and composition jeopardize their biodiversity. Several forest species are threatened because of reduced habitat quality and fragmentation or even habitat loss as a result of forest management activities. In response to this threat, integrated forest management (IFM) was developed in the early 1990s and has been applied over large spatial scales ever since. While IFM seeks to satisfy both human resource demands and ecosystem integrity, the whole forest matrix is affected and this may also have negative impacts on biodiversity. The concept of forest zoning (e.g., Triad) avoids these issues by physically separating land uses from each other. The zoning approach has been developed in the same period as IFM, but there are still very few examples of large-scale applications. This may be because its distinctiveness from IFM may not always seem clear and because forest zoning is not easily implemented. Here we explain these differences and show that IFM and the zoning approach are indeed different management paradigms. We advocate the use of high-yield plantations within the zoning paradigm as a means for biodiversity conservation and review the literature (with an emphasis on the northern hemisphere and on plantation forestry within a land-zoning approach) on impacts of forest management activities on biodiversity. Furthermore, we give advice on issues that require consideration when implementing forest zoning at both the stand and the landscape levels. We recommend several small changes in design and management of forest plantations as a means to significantly increase their biodiversity value. We conclude that while forest zoning seems an adequate strategy for the Canadian forestry sector, a shift in paradigm must carry over to policy-makers and legislation if this approach is to succeed. Key words: biodiversity, landbase zoning, forest management, intensive silviculture, plantation forests


Rangifer ◽  
2000 ◽  
Vol 20 (5) ◽  
pp. 158 ◽  
Author(s):  
Chris J. Johnson ◽  
Katherine L. Parker ◽  
Douglas C. Heard

We examined the foraging habits of the northern woodland caribou ecotype {Rangifer tarandus caribou) at the scale of the individual feeding site. Field data were collected in north-central British Columbia over two winters (Dec 1996-Apr 1998). We trailed caribou and measured vegetation characteristics (species composition and percent cover), snow conditions (depth, density, and hardness), and canopy closure at terrestrial and arboreal feeding sites, and at random sites where feeding had not occurred. Logistic regression was used to determine the attributes of feeding sites that were important to predicting fine scale habitat selection in forested and alpine areas. In the forest, caribou selected feeding sites that had a greater percent cover of Cladina mitis and Cladonia spp, lower snow depths, and a lower percentage of debris and moss. Biomass of Bryoria spp. at the 1-2 m stratum above the snow significantly contributed to predicting what trees caribou chose as arboreal feeding sites. In the alpine, caribou selected feeding sites with a greater percent cover of Cladina mitis, Cladina rangiferina, Cetraria cucullata, Cetraria nivalis, Thamnolia spp., and Stereocaulon alpinum as well as lower snow depths.


2011 ◽  
Vol 366 (1582) ◽  
pp. 3292-3302 ◽  
Author(s):  
Robert M. Ewers ◽  
Raphael K. Didham ◽  
Lenore Fahrig ◽  
Gonçalo Ferraz ◽  
Andy Hector ◽  
...  

Opportunities to conduct large-scale field experiments are rare, but provide a unique opportunity to reveal the complex processes that operate within natural ecosystems. Here, we review the design of existing, large-scale forest fragmentation experiments. Based on this review, we develop a design for the Stability of Altered Forest Ecosystems (SAFE) Project, a new forest fragmentation experiment to be located in the lowland tropical forests of Borneo (Sabah, Malaysia). The SAFE Project represents an advance on existing experiments in that it: (i) allows discrimination of the effects of landscape-level forest cover from patch-level processes; (ii) is designed to facilitate the unification of a wide range of data types on ecological patterns and processes that operate over a wide range of spatial scales; (iii) has greater replication than existing experiments; (iv) incorporates an experimental manipulation of riparian corridors; and (v) embeds the experimentally fragmented landscape within a wider gradient of land-use intensity than do existing projects. The SAFE Project represents an opportunity for ecologists across disciplines to participate in a large initiative designed to generate a broad understanding of the ecological impacts of tropical forest modification.


2014 ◽  
Author(s):  
Max Lambert

Suburban neighborhoods are rapidly spreading globally. As such, there is an increasing need to study the environmental and ecological effects of suburbanization. At large spatial extents, from county-level to global, remote sensing-derived land cover data, such as the National Land Cover Dataset (NLCD), have yielded insight into patterns of urbanization and concomitant large-scale ecological patterns in response. However, the components of suburban land cover (houses, yards, etc.) are dispersed throughout the landscape at a finer scale than the relatively coarse grain size (30m pixels) of NLCD may be able to detect. Our understanding of ecological processes in heterogeneous landscapes is reliant upon the accuracy and resolution of our measurements as well as the scale at which we measure the landscape. Analyses of ecological processes along suburban gradients are restricted by the currently available data. As ecologists are becoming increasingly interested in describing phenomena at spatial extents as small as individual households, we need higher-resolution landscape measurements. Here, I describe a simple method of translating the components of suburban landscapes into finer-grain, local land cover (LLC) data in GIS. Using both LLC and NLCD, I compare the suburban matrix surrounding ponds occupied by two different frog species. I illustrate large discrepancies in Forest, Yard, and Developed land cover estimates between LLC and NLCD, leading to markedly different interpretations of suburban landscape composition. NLCD, relative to LLC, estimates lower proportions of forest cover and higher proportions of anthropogenic land covers in general. These two land cover datasets provide surprisingly different descriptions of the suburban landscapes, potentially affecting our understanding of how organisms respond to an increasingly suburban world. LLC provides a free and detailed fine-grain depiction of the components of suburban neighborhoods and will allow ecologists to better explore heterogeneous suburban landscapes at multiple spatial scales.


1988 ◽  
Vol 64 (2) ◽  
pp. 116-120 ◽  
Author(s):  
René Doucet

The type and abundance of advance growth has been evaluated in 421 areas representing the major forest cover types in Quebec. Advance growth has been found to be abundant in mature stands of every cover type, except jack pine, and in all ecological zones. However its composition varied with cover types: balsam fir was the main species of advance growth in fir and mixedwood stands, while black spruce dominated advance growth in black spruce and jack pine stands. Most of the black spruce advance growth was from layer origin, especially in the black spruce ecological zone. Key words: Québec, regeneration.


2017 ◽  
Vol 95 (12) ◽  
pp. 975-984 ◽  
Author(s):  
H.G. Skatter ◽  
M.L. Charlebois ◽  
S. Eftestøl ◽  
D. Tsegaye ◽  
J.E. Colman ◽  
...  

Environment and Climate Change Canada (ECCC) calculated that 55% of Saskatchewan’s Boreal Shield has been disturbed by wildfire in the last 40 years. The 2012 Canadian Federal Recovery Strategy for woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)) states that these large-scale natural disturbances can cause caribou to cease use of portions of their range. This assumption neglects the potential habitat value of postfire residuals. We tested this assumption using 2 years of GPS data obtained from 56 female caribou to identify calving site selection. Seventy-nine calving events were identified from 91 individual calving seasons. For both calving and postcalving periods, woodland caribou preferred nonburned (>40 years) over burned habitats (≤40 years). Within burned areas, residual patches dominated by bogs–fens were preferred, indicating that burns with residuals are important woodland caribou calving habitat. The residuals may act as island refuges providing food–security, while surrounding burns provide reduced visual obstruction from which caribou can detect approaching predators. Although more data are necessary to make robust conclusions, this study provides novel insight into the ecological interactions of forest fires with woodland caribou in northern Saskatchewan, and offers important considerations regarding critical habitat identification and range-level planning to ensure all suitable caribou habitats are identified.


1993 ◽  
Vol 71 (3) ◽  
pp. 487-493 ◽  
Author(s):  
Tony E. Chubbs ◽  
Lloyd B. Keith ◽  
Shane P. Mahoney ◽  
Michael J. McGrath

Movements, sex and age structure, and habitat selection of adult woodland caribou (Rangifer tarandus caribou) were examined in relation to clear-cutting on summer range in east-central Newfoundland during 1987 – 1990. We obtained 2473 locations of 35 radio-collared caribou during at least two consecutive summers. Locations relative to clearcuts were determined for eight males and 27 females. Distances to existing clearcuts were compared with distances to those same geographic points prior to and following the summer in which clear-cutting occurred. Four males and 10 females maintained similar mean distances from clearcuts, 3 males and 12 females were farther away, and 2 females were closer. Three other females and one male were assumed to be too distant to be affected by clear-cutting. Of those found farther away from clearcuts, females were 2 – 3 times farther away than males. Among female caribou that maintained similar mean distances to clearcuts, habitat use during clear-cutting was similar to that before and afterwards. Females displaced by clear-cutting avoided open burns and hardwoods and selected mature black-spruce forest, whereas prior to cutting they used habitats in proportion to their availability. Sex and age ratios indicated that significantly fewer females and calves were present near clearcuts than elsewhere in the study area. Our results demonstrate that clear-cutting mature forests on summer range may affect the movements and distribution of woodland caribou.


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