Nonchalant neighbours: Space use and overlap of the critically endangered elongated tortoise

To prevent population extirpations we need to understand species’ requirements, especially for critically endangered species inhabiting biodiversity hotspots. Studying animal movement provides insights into such requirements and gauges protected area effectiveness. Southeast Asian protected areas are becoming isolated; thus, we must ensure existing areas can sustain populations. We used multi-year radio-telemetry with the critically endangered Elongated Tortoise (Indotestudo elongata) to assess: movements, space-use, and conspecific overlap in a small protected area –Sakaerat Biosphere Reserve, Thailand. Movements were weakly seasonal, increasing in hot and wet seasons compared to the dry season. Individuals annual space-use varied (4.24–55.57 ha), while frequently overlapping with conspecifics. Conspecific comparisons revealed males (n = 5) moved similarly to females (n = 12) but used larger areas. Explorations of temporal avoidance versus attraction reveal more instances of conspecific attraction than avoidance (20:8). Avoidance/attraction behaviour appeared disconnected from carapace length or mass; therefore, that conspecific interaction patterns may potentially be a result of resources (mates or food) rather than competition (i.e., no apparent evidence of smaller individuals avoiding larger individuals). Female-female attraction suggests an absence of resource exclusion tactics at the temporal resolution of our data. Male-female attraction may indicate reproductive movements coinciding with hot season, but we failed to detect significant interactive effects linking conspecific attraction or step length to proximity to breeding activity. Our observations of annual space-use and space overlap present critical components when designing robust population assessments; assessments that will underline any successful I. elongata conservation effort. When considered in the context of previous work connecting space overlap with population viability, our results suggest the biosphere population of I. elongata to be reproductive, with enough resources to be potentially viable; the findings help emphasise the importance of even relatively small protected natural areas.

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Space fit for a king: spatial ecology of king cobras (Ophiophagus hannah) in Sakaerat Biosphere Reserve, Northeastern Thailand

Amphibia-Reptilia ◽

10.1163/15685381-18000008 ◽

2019 ◽

Vol 40 (2) ◽

pp. 163-178 ◽

Cited By ~ 7

Author(s):

Benjamin Michael Marshall ◽

Colin Thomas Strine ◽

Max Dolton Jones ◽

Taksin Artchawakom ◽

Ines Silva ◽

...

Keyword(s):

Habitat Use ◽

Breeding Season ◽

Protected Area ◽

Spatial Ecology ◽

Radio Telemetry ◽

Biosphere Reserve ◽

Adult Males ◽

Anthropogenic Pressures ◽

Anthropogenic Landscapes ◽

Ophiophagus Hannah

Abstract A species’ spatial ecology has direct implications for that species’ conservation. Far-ranging species may be more difficult to conserve because their movements increase their chances of encountering humans. The movements can take them out of protected areas, which is especially risky for species that are routinely persecuted. The king cobra (Ophiophagus hannah), a large venomous elapid, is subject to anthropogenic pressures, such as persecution and habitat loss. Here we present results from a study using radio telemetry to quantify movements and habitat use of nine king cobras in and around a protected area in Northeast Thailand. This study is the first investigation into the movements and habitat use of king cobras outside of the Western Ghats, India. On average, the tracked king cobra’s use areas of 493.42 ± 335.60 ha (95% fixed kernel), moving 183.24 ± 82.63 m per day. King cobras did not remain in intact forested area. Five of the individuals frequently used the human-dominated agricultural areas surrounding the protected area, appearing to make regular use of irrigation canals. Two adult males showed increases in movements during the breeding season. One male’s increased breeding season range caused him to venture beyond the protected area, shifting his habitat use from intact forests to scrub in human-dominated areas. King cobras’ large home range and willingness to use anthropogenic landscapes merits special consideration from conservation planners.

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Restricted constrictors: Space use and habitat selection of native Burmese pythons in Northeast Thailand

10.1101/2020.09.17.302661 ◽

2020 ◽

Author(s):

Samantha Nicole Smith ◽

Max Dolton Jones ◽

Benjamin Michael Marshall ◽

Surachit Waengsothorn ◽

George A. Gale ◽

...

Keyword(s):

Habitat Selection ◽

Animal Movement ◽

Brownian Bridge ◽

Radio Telemetry ◽

Space Use ◽

Population Level ◽

Human Settlements ◽

Small Areas ◽

Agricultural Conversion ◽

Selection Of

AbstractAnimal movement and resource use are tightly linked. Investigating these links to understand how animals utilize space and select habitats is especially relevant in areas that have been affected by habitat fragmentation and agricultural conversion. We set out to explore the space use and habitat selection of Burmese pythons (Python bivittatus) in a patchy land use matrix dominated by agricultural crops and human settlements. We used radio telemetry to record daily locations of seven Burmese pythons over the course of our study period of approximately 22 months. We created dynamic Brownian Bridge Movement Models (dBBMMs) for all individuals, using occurrence distributions to estimate extent of movements and motion variance to reveal temporal patterns. Then we used integrated step selection functions to determine whether individual movements were associated with particular landscape features (aquatic agriculture, forest, roads, settlements, terrestrial agriculture, water), and whether there were consistent associations at the population level. Our dBBMM estimates suggested that Burmese pythons made use of small areas (98.97 ± 35.42 ha), with low mean individual motion variance characterized by infrequent moves and long periods at a single location. At both the individual and population level, Burmese pythons in the agricultural matrix were associated with aquatic environments. Only one individual showed a strong avoidance for human settlements which is troublesome from a human-wildlife conflict angle, especially as Burmese pythons have been observed entering human settlements and consuming livestock in our study site. Our study is one of the first to contribute to the knowledge of Burmese python ecology in their native range as the majority of studies have focused on invasive populations.

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Movement syndromes of a Neotropical frugivorous bat inhabiting heterogeneous landscapes in Brazil

Movement Ecology ◽

10.1186/s40462-021-00266-6 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Patricia Kerches-Rogeri ◽

Danielle Leal Ramos ◽

Jukka Siren ◽

Beatriz de Oliveira Teles ◽

Rafael Souza Cruz Alves ◽

...

Keyword(s):

Site Fidelity ◽

Animal Movement ◽

Radio Telemetry ◽

Food Resource ◽

Movement Behavior ◽

Movement Activity ◽

Landscape Features ◽

Heterogeneous Landscapes ◽

Movement Data ◽

High Site

Abstract Background There is growing evidence that individuals within populations can vary in both habitat use and movement behavior, but it is still not clear how these two relate to each other. The aim of this study was to test if and how individual bats in a Stunira lilium population differ in their movement activity and preferences for landscape features in a correlated manner. Methods We collected data on movements of 27 individuals using radio telemetry. We fitted a heterogeneous-space diffusion model to the movement data in order to evaluate signals of movement variation among individuals. Results S. lilium individuals generally preferred open habitat with Solanum fruits, regularly switched between forest and open areas, and showed high site fidelity. Movement variation among individuals could be summarized in four movement syndromes: (1) average individuals, (2) forest specialists, (3) explorers which prefer Piper, and (4) open area specialists which prefer Solanum and Cecropia. Conclusions Individual preferences for landscape features plus food resource and movement activity were correlated, resulting in different movement syndromes. Individual variation in preferences for landscape elements and food resources highlight the importance of incorporating explicitly the interaction between landscape structure and individual heterogeneity in descriptions of animal movement.

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The home-range concept: are traditional estimators still relevant with modern telemetry technology?

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2010.0093 ◽

2010 ◽

Vol 365 (1550) ◽

pp. 2221-2231 ◽

Cited By ~ 268

Author(s):

John G. Kie ◽

Jason Matthiopoulos ◽

John Fieberg ◽

Roger A. Powell ◽

Francesca Cagnacci ◽

...

Keyword(s):

Home Range ◽

New Technologies ◽

Animal Movement ◽

Space Use ◽

Ease Of Use ◽

Home Ranges ◽

Data Intensive ◽

Use Patterns ◽

Location Data ◽

Utilization Distributions

Recent advances in animal tracking and telemetry technology have allowed the collection of location data at an ever-increasing rate and accuracy, and these advances have been accompanied by the development of new methods of data analysis for portraying space use, home ranges and utilization distributions. New statistical approaches include data-intensive techniques such as kriging and nonlinear generalized regression models for habitat use. In addition, mechanistic home-range models, derived from models of animal movement behaviour, promise to offer new insights into how home ranges emerge as the result of specific patterns of movements by individuals in response to their environment. Traditional methods such as kernel density estimators are likely to remain popular because of their ease of use. Large datasets make it possible to apply these methods over relatively short periods of time such as weeks or months, and these estimates may be analysed using mixed effects models, offering another approach to studying temporal variation in space-use patterns. Although new technologies open new avenues in ecological research, our knowledge of why animals use space in the ways we observe will only advance by researchers using these new technologies and asking new and innovative questions about the empirical patterns they observe.

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Altitudinal movements and conservation of Bare-necked Umbrellabird Cephalopterus glabricollis of the Tilarán Mountains, Costa Rica

Bird Conservation International ◽

10.1017/s0959270903003046 ◽

2003 ◽

Vol 13 (1) ◽

pp. 45-58 ◽

Cited By ~ 25

Author(s):

Johel Chaves-Campos ◽

J. Edgardo Arévalo ◽

Mariamalia Araya

Keyword(s):

Costa Rica ◽

Breeding Season ◽

Protected Area ◽

Radio Telemetry ◽

Fruit Breeding ◽

Potential Threat ◽

Fruit Abundance ◽

Transect Counts ◽

Using Data ◽

High Elevations

Bare-necked Umbrellabird Cephalopterus glabricollis is endemic to Costa Rica and western Panama. It eats fruit, breeding at high elevations (≥ 800 m) and migrating to lower elevations during the non-breeding season. Using data from transect counts and radio-telemetry, we monitored bird movements in a protected area (Monteverde–Arenal–San Ramón reserves) in the Tilarán Mountains, Costa Rica. We also monitored fruit abundance along an altitudinal gradient to explore the potential relationship between bird movements and the abundance of the fruits this species consumed. The presence and abundance of umbrellabirds at high elevations (1,400 m) during the breeding season (March–June) coincided with the highest peak of fruit abundance. The presence of umbrellabirds in the lowlands (400 m) during the non-breeding season overlapped with the period of highest fruit abundance at these elevations. At middle elevations, bird presence and abundance did not correlate with fruit abundance. Radio-tagged birds left the protected area during the non-breeding season and there were no umbrellabirds inside the protected area during this period. Habitats where this species bred were well represented in the protected area but the habitat where they spent the non-breeding season was poorly represented, and was not adequately protected. This represents a potential threat to this species in the Tilarán Mountains.

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Multi-taxonomic survey in the Sierra del Abra Tanchipa Biosphere Reserve

Biota Neotropica ◽

10.1590/1676-0611-bn-2020-1050 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Francisco Javier Sahagún-Sánchez ◽

José Arturo De-Nova

Keyword(s):

Protected Area ◽

Biological Diversity ◽

Biosphere Reserve ◽

Natural Protected Areas ◽

Ecological Corridor ◽

Sierra Madre ◽

Baseline Information ◽

Taxonomic Groups ◽

Management And Conservation ◽

Conservation Of Biodiversity

Abstract: Studies on biological diversity are essential to generate baseline information in natural protected areas. In the present study, we developed a multi-taxonomic inventory in the Sierra del Abra Tanchipa Biosphere Reserve, located northeast of San Luis Potosí, Mexico. Systematic samplings were performed between January 2017 to May 2018, for the taxonomic groups of flora, amphibians, reptiles, birds, and mammals. A total of 3 730 records of 683 species were obtained, corresponding to 427 species of flora, 10 of amphibians, 20 of reptiles, 192 of birds, and 34 of mammals, from which 47 species are threatened. The results obtained represent the critical biodiversity that can be found in this natural protected area. The information will be useful for decision-making on the management and conservation of biodiversity in the Sierra Madre Oriental’s ecological corridor.

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Arboreal aperitifs: Space use and activity of a major songbird nest predator in a tropical Thailand forest

10.1101/2021.02.09.430242 ◽

2021 ◽

Author(s):

Anji D’souza ◽

George Gale ◽

Benjamin Michael Marshall ◽

Daphawan Khamcha ◽

Surachit Waengsothorn ◽

...

Keyword(s):

Brownian Bridge ◽

Radio Telemetry ◽

Space Use ◽

Evergreen Forest ◽

Boiga Irregularis ◽

Forest Fragment ◽

Predator Species ◽

Avian Nest ◽

Nest Predator ◽

Nesting Season

ABSTRACTPredator-prey interactions are fundamental drivers of population dynamics, yet rarely are both predator and prey species simultaneously studied. Despite being significant, widespread avian nest predators, research on the ecology of Southeast Asian snakes in relation to birds remains scarce. The green cat snake (Boiga cyanea) is a primary nest predator, responsible for ≈24% of forest songbird depredation in Northeast Thailand. We explored both diurnal and nocturnal movements of 14 (5 male, 9 female) adult B. cyanea with radio-telemetry for an average of 68 ± 16 days per individual, between 21 October 2017 and 8 June 2019 in the dry evergreen forest of the Sakaerat Biosphere Reserve (SBR). We quantified area of space use (ha) and activity through motion variance (Ϭm2) during the study period using dynamic Brownian bridge movement models, and linked our findings to a simultaneously-run avian nest monitoring study, initiated in 2013 within the same forest fragment. On average, movements, space use and activity differed between males and females, and between the avian nesting and non-nesting seasons. Males moved 51.37 m/day farther than females. They used areas 15.09 ha larger than females, and their activity was 3.91 Ϭm2 higher than that of females. In general, individuals moved 50.30 m/day farther during the nesting season than the non-nesting season. The snakes used areas 9.84 ha larger during the nesting season than the non-nesting season, and their activity during the nesting season was 3.24 Ϭm2 higher than that during the non-nesting season. All individuals were exclusively nocturnal, moving throughout the night, and often descending from higher diurnal refugia (>2 m) to forage closer to the ground after sunset. Boiga cyanea activity followed a similar trend to that of the recorded nest depredations at SBR. Our study links snake activity to nest depredations in SBR. Our openly-available data may yield further insight when combined with other major avian nest predator species like the congeneric invasive brown tree snake (Boiga irregularis) on the island of Guam.

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