Movement patterns within an urban population of fire salamanders highlight the importance of conserving small habitat patches

2021 ◽  
Author(s):  
I. Kiss ◽  
J. Vörös ◽  
A.J. Hamer
2008 ◽  
Vol 35 (1) ◽  
pp. 50 ◽  
Author(s):  
Skye Wassens ◽  
Robyn J. Watts ◽  
Amy Jansen ◽  
David Roshier

Within the semiarid regions of New South Wales, Australia, the endangered southern bell frog (Litoria raniformis) occupies a landscape that is characterised by unpredictable rainfall and periodic flooding. Limited knowledge of the movement and habitat-occupancy patterns of this species in response to flood events has hampered conservation efforts. We used radio-tracking to assess changes in movement patterns and habitat occupancy of L. raniformis (n = 40) over three different periods (November, January and April/May) that coincided with the flooding, full capacity and subsequent drying of waterbodies within an irrigation landscape. We assessed (1) the use of permanent and ephemeral habitats in response to flooding and drying and (2) distances moved, turning angles and dispersion of frogs during wetland flooding, full capacity and drying. Individuals remained in permanent waterbodies in November but had abandoned these areas in favour of flooded ephemeral waterbodies by January. As the ephemeral waterbodies dried, radio-tracked individuals moved back into permanent waterbodies. The movement patterns of radio-tracked individuals were significantly different in the three radio-tracking periods, but did not differ significantly between sexes. Individuals moved significantly greater distances over 24 h, in straighter lines and movements were more dispersed while they occupied ephemeral waterbodies during January than when they occupied permanent waterbodies during November and April/May. Local weather conditions did not influence movement patterns when all three tracking periods were modelled together using a single linear stepwise regression. The dynamic distribution of habitat patches over space and time, combined with changing patterns of resource utilisation and movement of L. raniformis, highlights the importance of incorporating both permanent and ephemeral habitat patches into conservation plans. Reductions in flood frequency and extent of ephemeral wetlands due to modified flooding regimes have the capacity to limit dispersal of this species, even when permanent waterbodies remain unchanged.


2021 ◽  
Vol 11 (13) ◽  
pp. 5987
Author(s):  
Fatema Rahimi ◽  
Abolghasem Sadeghi-Niaraki ◽  
Mostafa Ghodousi ◽  
Soo-Mi Choi

GPS-equipped vehicles are an effective approach for acquiring urban population movement patterns. Attempts have been made in the present study in order to identify the population displacement pattern of the study region using taxis’ origin and destination data, and then model the parameters affecting the population displacement pattern and provide an ultimate model in order to predict pick-up and drop-off locations. In this way, the passenger pick-up and drop-off locations have been identified in order to obtain the population movement pattern. In this study, Moran’s I index was used to measure the spatial autocorrelation, and hot spot analysis was used to analyze spatial patterns of pick-up and drop-off locations. Effective parameters modeling was performed using the Poisson regression. The results of the spatiotemporal distribution map for pick-up and drop-off locations indicated a similarity in patterns and equal results for some locations. Results also indicated different features of spatial distribution during different hours of the day. Spatial autocorrelation analysis results indicated a low probability of randomness in the general spatial distribution of the locations. The result of modeling the parameters shows the positive effect of the parameters on the pattern of population movement, and according to the p-value of 0.000, Poisson regression is significant for the pick-up and drop-off locations. The modeling results also highlighted the importance of movement patterns in recognizing urban hot spots, which is valuable for policymakers and urban planners.


2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Damber Bista ◽  
Greg S. Baxter ◽  
Nicholas J. Hudson ◽  
Sonam Tashi Lama ◽  
Janno Weerman ◽  
...  

Abstract Background Habitat specialists living in human-dominated landscapes are likely to be affected by habitat fragmentation and human disturbances more than generalists. But there is a paucity of information on their response to such factors. We examined the effect of these factors on movement patterns of red pandas Ailurus fulgens, a habitat and diet specialist that inhabits the eastern Himalaya. Methods We equipped 10 red pandas (six females, four males) with GPS collars and monitored them from September 2019 to March 2020 in Ilam, eastern Nepal. We collected habitat and disturbance data over four seasons. We considered geophysical covariates, anthropogenic factors and habitat fragmentation metrics, and employed linear -mixed models and logistic regression to evaluate the effect of those variables on movement patterns. Results The median daily distance travelled by red pandas was 756 m. Males travelled nearly 1.5 times further than females (605 m). Males and sub-adults travelled more in the mating season while females showed no seasonal variation for their daily distance coverage. Red pandas were relatively more active during dawn and morning than the rest of the day, and they exhibited seasonal variation in distance coverage on the diel cycle. Both males and females appeared to be more active in the cub-rearing season, yet males were more active in the dawn in the birthing season. Two sub-adult females dispersed an average of 21 km starting their dispersal with the onset of the new moon following the winter solstice. The single subadult male did not disperse. Red pandas avoided roads, small-habitat patches and large unsuitable areas between habitat patches. Where connected habitat with high forest cover was scarce the animals moved more directly than when habitat was abundant. Conclusions Our study indicates that this habitat specialist is vulnerable to human disturbances and habitat fragmentation. Habitat restoration through improving functional connectivity may be necessary to secure the long-term conservation of specialist species in a human-dominated landscape. Regulation of human activities should go in parallel to minimize disturbances during biologically crucial life phases. We recommend habitat zonation to limit human activities and avoid disturbances, especially livestock herding and road construction in core areas.


2020 ◽  
Vol 42 (1) ◽  
pp. 38
Author(s):  
Karlene Bain ◽  
Adrian Francis Wayne ◽  
Roberta Bencini

We used radio-telemetry to investigate the home-range size and movement patterns of the quokka (Setonix brachyurus) in the southern forests of Western Australia to assess the ability of animals to move between increasingly segregated habitat patches and to identify implications for metapopulation function. We found that quokkas in this region have a much larger home range (71 ± 5.8 ha) and move larger distances (up to 10 km per night) than previously reported for this species in other regions. Temporal and sex variations in home-range size, overlap and movement patterns provided insights into the social structure, reproductive strategies and resource availability for the species in this part of its range. Quokkas moved up to 14 km between habitat patches, where these patches were connected by dense riparian vegetation. While riparian vegetation was used exclusively for movement between habitat patches, quokkas spent only 40% of their time in this ecotype. The current management paradigm of protecting linear riparian vegetation as habitat for quokkas is important for maintaining habitat connectivity, but is unlikely to meet broader habitat and spatial requirements. Management of preferred habitat as well as riparian corridors is necessary for the maintenance of a functional metapopulation.


2020 ◽  
Vol 17 (2) ◽  
pp. 66-73
Author(s):  
R. D. Oktyabrskiy

The article is devoted to the justification of the need to reduce the population density in the residential development of cities. The analysis of vulnerability of the urban population from threats of emergency situations of peace and war time, and also an assessment of provision of the city by a road network is given. Proposals have been formulated to reduce the vulnerability of the urban population in the long term and to eliminate traffic congestion and congestion — jams.


Sign in / Sign up

Export Citation Format

Share Document