scholarly journals Edge-habitat Use by Northwestern Gartersnakes (Thamnophis ordinoides) in Saanich, British Columbia

2017 ◽  
Vol 131 (1) ◽  
pp. 37-45
Author(s):  
Graham P. Dixon-MacCallum ◽  
Katie A.H. Bell ◽  
Patrick T. Gregory

Understanding habitat requirements of species is fundamental for their conservation and urban parks can provide key habitat for species in otherwise disturbed settings. Northwestern Gartersnakes (Thamnophis ordinoides) are common in parks in Saanich, British Columbia, but their specific habitat requirements are poorly understood. Based on previous studies and thermoregulatory needs of snakes, we predicted that edges, particularly field margins, would be heavily used by active snakes. We therefore used surveys that focused on edges to find snakes and measured edge-habitat use by comparing habitat variables at locations where snakes were found to the same variables at nearby random locations. Habitat variables included composition and structure of vegetation, substrate temperature, aspect, and slope. Overall, litter depth, canopy cover, a lack of bare ground and woody vegetation were the most important habitat variables for determining where snakes were found. our results provide a preliminary assessment to improve our understanding of habitat use for this species. The abundance of snakes found while surveying edges supports our initial assumption that edges are important habitat features but more work is required using multiple survey methods to further test this hypothesis.

2007 ◽  
Vol 121 (2) ◽  
pp. 155 ◽  
Author(s):  
Astrid Vik Stronen ◽  
Paul Paquet ◽  
Stephen Herrero ◽  
Seán Sharpe ◽  
Nigel Waters

During 1997–1999, 32 Woodland Caribou (Rangifer tarandus caribou) were translocated from the Sustut Herd to the Telkwa Mountains in westcentral British Columbia to augment recovery of the Telkwa Caribou Herd. The animals were fitted with radiocollars and located during 1997–2000 to determine selection of habitat features and terrain variables. Six Caribou calves were also collared to determine causes and timing of calf mortality during summer 1999. Defining available habitat for newly translocated animals is often arbitrary and subjective, and we based the analyses on ranks for habitat use and availability as this is less sensitive to the inclusion or exclusion of a questionable resource. This method represents some loss of information but provides indications of the relative importance of various habitat types without classifying any as avoided. High elevation habitat (> 1700 masl) on moderate slopes (16 – 45°) received the highest ranks, as did “warm” (136 – 315°) aspects and forests > 250 years old. Three calves died shortly after birth. One calf appeared to have been killed by predation, likely by a Golden Eagle (Aquila chrysaetos), and one calf was abandoned by the cow. Cause of death for the third calf is unknown. To assess habitat use associated with calving we compared summer locations with data obtained throughout the rest of 1999 for eight cows with calves and eight without calves. We found significant difference in use of elevation during calving time, when cows with calves remained at high elevations and barren cows generally descended to lower elevation habitat. Surveys conducted in 2005, five years after the completion of the initial study, produced a count of approximately 90 Caribou. This suggests that in the short term, the translocation was successful in re-establishing a self-sustaining Caribou population in the Telkwa Mountains.


PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9439
Author(s):  
Bing Zhang ◽  
Bingxian Wu ◽  
Daode Yang ◽  
Xiaqiu Tao ◽  
Mu Zhang ◽  
...  

Habitat directly affects the population size and geographical distribution of wildlife species, including the Mangshan pit viper (Protobothrops mangshanensis), a critically endangered snake species endemic to China. We searched for Mangshan pit viper using randomly arranged transects in their area of distribution and assessed their habitat association using plots, with the goals of gaining a better understanding of the habitat features associated with P. mangshanensis detection and determining if the association with these features varies across season. We conducted transect surveys, found 48 individual snakes, and measured 11 habitat variables seasonally in used and random plots in Hunan Mangshan National Nature Reserve over a period of 5 years (2012–2016). The important habitat variables for predicting Mangshan pit viper detection were fallen log density, shrub density, leaf litter cover, herb cover and distance to water. In spring, summer and autumn, Mangshan pit viper detection was always positively associated with fallen log density. In summer, Mangshan pit viper detection was related to such habitats with high canopy cover, high shrub density and high herb cover. In autumn, snakes generally occurred in habitats near water in areas with high fallen log density and tall shrubs height. Our study is the first to demonstrate the relationship between Mangshan pit viper detection and specific habitat components. Mangshan pit viper detection was associated with habitat features such as with a relatively high fallen log density and shrub density, moderately high leaf litter cover, sites near stream, and with lower herb cover. The pattern of the relationship between snakes and habitats was not consistent across the seasons. Identifying the habitat features associated with Mangshan pit viper detection can better inform the forestry department on managing natural reserves to meet the habitat requirements for this critically endangered snake species.


1989 ◽  
Vol 67 (9) ◽  
pp. 2212-2219 ◽  
Author(s):  
M. O. Hammill ◽  
T. G. Smith

The relationship between the distribution of ringed seals, Phoca hispida, and habitat was examined in Barrow Strait, Northwest Territories. Density of seal breathing holes was used as an index of seal abundance. Birth lairs were associated with the largest snowdrifts. Lair formation can occur within 24 h after a snowdrift forms over the top of a breathing hole. Seal structures were associated with ridges consisting of ice pieces 15–25 cm thick projecting upwards to a height of 80–150 cm. In 1975 and 1986, the combination of date of ice consolidation and snow depth were the most important habitat features affecting the distribution of ringed seals structures. This was also true with respect to distribution of birth lairs and undefined haul-out lairs, but no relationship was identified between density of structures used by males and habitat. Snow cover and date of ice consolidation were not identified as important habitat variables in 1984 and 1985 when overall distribution of ice in Barrow Strait was very different. Birth lairs were not seen before 4 April, but were found in increasing frequency as the season progressed. Male structures were evident in late March, but were not found after mid-May.


2012 ◽  
Vol 90 (7) ◽  
pp. 875-884 ◽  
Author(s):  
A.B. Edworthy ◽  
K.M.M. Steensma ◽  
H.M. Zandberg ◽  
P.L. Lilley

Terrestrial molluscs have declined globally, often as a result of habitat loss and fragmentation. Many land snails are poor dispersers and exist in isolated habitat patches. The Oregon forestsnail ( Allogona townsendiana (I. Lea, 1838)) coincides with the most densely populated region of British Columbia and is listed as endangered in Canada. To investigate the dispersal distances and habitat-use patterns of Oregon forestsnails, we tagged and tracked 21 adult snails at Langley, British Columbia, for up to 3 years (2005–2008). The maximum daily dispersal distance for a snail was 4.5 m and the maximum displacement that we observed for a snail was 32.2 m during 3 years. Snails occupied home-range areas of 18.4–404.4 m2, often overlapping both forest and meadow habitat. Their home-range sizes were smaller in habitats with high availability of stinging nettle ( Urtica dioica L.), which may be an indicator of high-quality habitat. Our results suggest that the Oregon forestsnail is a relatively sedentary species with limited dispersal ability in its adult stage. Although Oregon forestsnails are likely unable to colonize suitable habitat independently, remnant forest–meadow mosaic patches such as our study site provide valuable habitat for Oregon forestsnail, which are supplementary to large tracts of intact forest where most of their populations are found.


1998 ◽  
Vol 85 (1-2) ◽  
pp. 47-53 ◽  
Author(s):  
Ralph Grundel ◽  
Noel B. Pavlovic ◽  
Christina L. Sulzman

2019 ◽  
Vol 11 (6) ◽  
pp. 13667-13679 ◽  
Author(s):  
Mahfut Sodik ◽  
Satyawan Pudyatmoko ◽  
Pujo Semedi Hargo Yuwono ◽  
Muhammad Ali Imron

Habitat loss and forest fragmentation have negative impacts on Javan Slow Loris Nycticebus javanicus, a Critically Endangered nocturnal primate endemic to Java.  Reports confirmed that less than 9% of forest area remains on Java Island.  One of the remaining natural habitats of the Javan Slow Loris is the fragment of Kemuning Forest in Temanggung Regency, Central Java.  The purpose of this study was to determine resource selection and habitat variables that determine the presence of Javan Slow Loris.  Habitat variables measured were basal area, tree connectivity, crown coverage on tree stage, slope, elevation, and distance to river.  Data analysis performed was logistic regression, likelihood ratio test, and Akaike’s Information Criterion with a backward elimination procedure.  We also used direct observation and interviews with locals to collect data on environment and anthropogenic features of this forest.  The results showed that the Javan Slow Loris uses resources selectively on a microhabitat scale.  The habitat factors that influence the probability of resource selection by the species are canopy cover and slope.  Habitat characteristics preferred by the Javan Slow Loris in Kemuning Forest are secondary lowland tropical rainforest with dense canopy cover located on a steep slope with low level of habitat disturbances.  Although this study uses a small sample size, the expectation is that the results can be used as preliminary information for the habitat and population management of Javan Slow Loris in Kemuning Forest to guide conservation efforts and design management strategies.


1998 ◽  
Vol 25 (5) ◽  
pp. 489 ◽  
Author(s):  
Chris R. Pavey

I examined habitat use by eastern horseshoe bats, Rhinolophus megaphyllus, in a fragmented woodland mosaic in south-east Queensland, Australia. I predicted that the species would forage within the remaining woodland remnants in the mosaic, because its flight pattern and auditory system are adapted for locating and capturing prey in cluttered habitat (i.e. close to and within vegetation). I studied habitat use by light-tagging and radio-tagging bats that roosted in a disused mine in a large woodland fragment. I observed bats within an area of 95 ha, which was composed of grassland (71% of area), woodland (14%), and edge habitat (boundary of woodland and grassland, and isolated trees in grassland – 15%). Bats foraged in woodland and edge habitat but not over grassland, and used woodland significantly more often than expected by its availability. Commuting bats left the woodland fragment in which the roost was located by one of two routes, both of which led into riparian woodland. One route was entirely within woodland, whereas the other route crossed 250 m of open ground. The study indicates that R. megaphyllus should respond negatively to the fragmentation of woodland and forest because this process will reduce the availability of its preferred foraging habitat.


2016 ◽  
Vol 130 (3) ◽  
pp. 224
Author(s):  
Louise Porto ◽  
Crystal Lawrence

Umatilla Dace (Rhinichthys umatilla, Cyprinidae) are endemic to the Columbia River Basin. In Canada, this species is assessed as “threatened”. Little is known about its life history, especially with respect to spawning in the wild. A total of 688 specimens were captured, including 39 mature males and females displaying spawning colouration and tubercles, during minnow trapping and electrofishing surveys conducted on the Slocan River in southern British Columbia, Canada. Fertilized eggs were not observed, but eggs and milt were expressed from ripe individuals. Spawning was estimated to occur from mid-July to mid-September. Aquatic macrophytes and flooded terrestrial vegetation were important habitat features for mature Umatilla Dace leading up to the spawning period on the Slocan River. To our knowledge this is the first time that Umatilla Dace have been captured in spawning condition and observed with spawning colouration and tubercles in the wild in Canada. Results of this study will aid the development of recovery plans and management for this species in British Columbia.


2003 ◽  
Vol 117 (4) ◽  
pp. 565 ◽  
Author(s):  
Kim G. Poole ◽  
Douglas C. Heard

To identify the potential for adverse effects of forest development on Mountain Goats (Oreamnos americanus), we documented the patterns of forest use by goats and the factors influencing goat habitat use. We used a combination of 15 very high frequency (VHF) and six global positioning system (GPS) radiocollars to document the distribution and movements of 21 (15 female, 6 male) goats from 1997 to 1999 in the mountains surrounding the Robson Valley in east-central British Columbia. Because canopy closure reduces the likelihood that a GPS receiver will obtain a location fix, we estimated that GPS collars underrepresented forest use by about 23%. Three goats used separate winter and summer ranges separated by 8–13 km, while most simply exhibited seasonal shifts in elevation. In winter, goats were more often at lower elevations, in commercial forest stands, on southerly aspects, and moved less each hour and over the course of the winter. Goat use declined in areas >500 m from escape terrain and goats were found lower in elevation from evening to dawn compared to daylight hours. Collared goats used high elevation licks, which were either within their home range, or in two cases, 6 and 14 km from their typical home range. We documented use of known mid-elevation mineral licks by three collared goats, but no use of known low elevation (valley bottom and lower slopes) mineral licks. Robson Valley goats appeared to be at relatively low risk from disturbances related to logging, because although forest use was documented during winter, it occurred primarily on high elevation, steep slopes where trees are currently of low commercial value, and goats made little use of low elevation mineral licks. We recommend that in this area a forested buffer of 500 m around cliffs be left to reduce the possibility of adverse effects on goats especially, on southerly aspects above 1300 m.


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