Vulture restaurants and their role in reducing diclofenac exposure in Asian vultures

The provision of supplementary food at vulture restaurants is a well-established tool in the conservation of vulture species. Among their many applications, vulture restaurants are used to provide a safe food source in areas where carcasses are commonly baited with poisons. Rapid and extensive declines of vultures in the Indian subcontinent have been attributed to the toxic effects of diclofenac, a pharmaceutical used in the treatment of livestock, to which vultures are exposed while feeding on the carcasses of treated animals. A vulture restaurant was established at the Oriental White-backed Vulture Gyps bengalensis colony at Toawala, in Punjab province Pakistan, to test the effectiveness of the technique in modifying ranging behaviour and mortality at the colony. Six male vultures were fitted with satellite transmitters to describe variation in movement and home-range during periods when safe food was alternately available and withheld at the vulture restaurant. There was considerable variation in individual home-range size (minimum convex polygons, MCP, of 1,824 km2 to 68,930 km2), with birds occupying smaller home-ranges centred closer to the restaurant being more successful in locating the reliable source of food. Fixes showed that 3 of the tagged vultures fed at the vulture restaurant and the home-range of each bird declined following their initial visit, with a 23–59% reduction in MCP. Mean daily mortality during provisioning was 0.072 birds per day (8 birds in 111 days), compared with 0.387 birds per day (41 birds in 106 days) during non-provisioning control periods. Vultures tended to occupy greater home-ranges, cover greater distances each day and spend proportionately more time in the air during the late brooding and post-breeding seasons. Attendance at the vulture restaurant also declined during this period with fewer birds visiting less often and no tagged vultures visiting the vulture restaurant at all. These findings indicate that vulture restaurants can reduce, but not eliminate, vulture mortality through diclofenac exposure and represent a valuable interim measure in slowing vulture population decline locally until diclofenac can be withdrawn from veterinary use.

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Selection of foraging habitat and diet of the Hoopoe Upupa epops in the mosaic-like cultural landscape of Goričko (NE Slovenia)

Acrocephalus ◽

10.1515/acro-2015-0008 ◽

2015 ◽

Vol 36 (166-167) ◽

pp. 109-132

Author(s):

Mojca Podletnik ◽

Damijan Denac

Keyword(s):

Home Range ◽

Agricultural Landscape ◽

Population Decline ◽

Home Range Size ◽

Range Size ◽

Foraging Habitat ◽

Convex Polygons ◽

Upupa Epops ◽

Mole Crickets ◽

Selection Of

In 2012 and 2013, the selection of foraging habitats and the diet of the Hoopoe Upupa epops were studied in the Goričko area, where a significant population decline of the species has been recorded in the past 15 years. Goričko is an area with a well-preserved traditional mosaic-like agricultural landscape very rich in biodiversity which, however, is disappearing. The diet was determined using automatic camera recordings of prey brought to chicks by parents. Mole crickets Gryllotalpa gryllotalpa were the most dominant prey (35.4% frequency and 81.3% biomass of prey), followed by Scarab beetles larvae Scarabaeidae, caterpillars Lepidoptera larvae and True flies Diptera. Feeding frequency was highest in the period of most intensive chick growth (between 8 and 21 days of age). Selection of foraging habitat was researched by observation of birds during foraging. Hoopoes foraged mostly in mown meadows and grassy courtyards and, to a lesser extent, on sandy cart tracks and road edges. These habitats were characterized by low vegetation and patches of bare ground that enabled Hoopoes to forage efficiently. Home range size was determined using minimum convex polygons. The maximum home range size was between 42.9 and 57.7 ha, while the percentage of foraging habitats within the home range did not exceed 18%. Based on our results, we propose the following measures for effective Hoopoe conservation in the area: maintaining the present range of existing unimproved meadows, stopping the conversion of meadows into fields, restoring fields to meadows, prohibiting the use of pesticides targeting Mole crickets.

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Sexual and environmental variation in the space requirements of the Critically Endangered geometric tortoise, Psammobates geometricus

Amphibia-Reptilia ◽

10.1163/156853812x634071 ◽

2012 ◽

Vol 33 (2) ◽

pp. 185-197 ◽

Cited By ~ 9

Author(s):

Margaretha Hofmeyr ◽

Ulric van Bloemestein ◽

Brian Henen ◽

Craig Weatherby

Keyword(s):

Home Range ◽

Habitat Degradation ◽

Space Use ◽

Home Range Size ◽

Home Ranges ◽

Convex Polygons ◽

Wet Season ◽

Mating Opportunities ◽

Space Requirements ◽

Nesting Season

Psammobates geometricus has a limited distribution in the southwestern Cape, South Africa, where it occurs in small habitat fragments separated by agricultural and urban developments. Space use and its determining factors thus represent critical information for the effective conservation of this species. We used radiotelemetry and thread-trailing to study the movement patterns and space use of geometric tortoises over an annual cycle, and estimated home ranges with minimum convex polygons and fixed-kernel methods. Home range size of geometric tortoises showed large inter-individual variation, and for females, a positive relationship to body size. Females, the larger sex, had larger home ranges and mean daily displacements than males had. Female space use was high through most of the year, except in the wet season, when food was abundant, temperatures relatively low, and soft soils allowed easy nesting. Males used more space and displaced further in the non-nesting than nesting season, perhaps to optimise mating opportunities in the non-nesting season before females ovulate. Home ranges were more elongate and overlapped more in fallow fields than in natural vegetation, suggesting that habitat degradation alters home range structure. The space geometric tortoises used for their annual activities ranged from 1.02 to 44.85 ha. The large home ranges and effects of habitat degradation should influence the size of reserves, and the destiny of geometric tortoises in small habitat fragments.

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Annual vs. Multiple-Year Home Range Sizes of Individual Blanding's Turtles, Emydoidea blandingii, in Central Wisconsin

The Canadian Field-Naturalist ◽

10.22621/cfn.v122i1.545 ◽

2008 ◽

Vol 122 (1) ◽

pp. 61 ◽

Cited By ~ 9

Author(s):

Matthew Schuler ◽

Richard P. Thiel

Keyword(s):

Home Range ◽

Space Use ◽

Home Range Size ◽

Range Size ◽

Home Ranges ◽

Convex Polygons ◽

Short Term ◽

Emydoidea Blandingii ◽

Significant Difference ◽

Short Time

Most studies of home ranges occur over short time periods and may not represent the spacial requirements of long-lived organisms such as turtles. Home ranges of 18 individual Blanding’s Turtles (Emydoidea blandingii) were measured using minimum convex polygons. Annual space use was compared to multi-year space use by individual turtles. We found a significant difference between annual home range size (25.5 hectares) and multi-year (two to six years) home range size (65.7 hectares; n = 18, P = 0.016). Caution should be employed when making management decisions based on short-term studies of long lived species.

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Female tiger Panthera tigris home range size and prey abundance: important metrics for management

Oryx ◽

10.1017/s0030605312001408 ◽

2014 ◽

Vol 48 (3) ◽

pp. 370-377 ◽

Cited By ~ 40

Author(s):

Achara Simcharoen ◽

Tommaso Savini ◽

George A. Gale ◽

Saksit Simcharoen ◽

Somphot Duangchantrasiri ◽

...

Keyword(s):

Home Range ◽

Significant Negative Correlation ◽

Home Range Size ◽

Range Size ◽

Prey Abundance ◽

Published Data ◽

Home Ranges ◽

Panthera Tigris ◽

Convex Polygons ◽

The Mean

AbstractTigers Panthera tigris are highly threatened and continue to decline across their entire range. Actions to restore and conserve populations need to be based on science but, in South-east Asia, information on ecology and behaviour of tigers is lacking. This study reports the relationship between the home range size of female tigers and prey abundance, using data from radio-collared tigers in Huai Kha Khaeng Wildlife Sanctuary, Thailand, and published data from other studies. A total of 11 tigers, four males and seven females, were fitted with global positioning system collars, to estimate home ranges using 95 and 100% minimum convex polygons (MCP). Prey abundance was estimated by faecal accumulation rates. The mean home range size of male tigers was 267 and 294 km2 based on 95 and 100% MCPs, respectively; the mean female home range size was 70 and 84 km2, respectively. Territories of male and female tigers had little overlap, which indicated both sexes were territorial. Mean densities of the prey species sambar Rusa unicolor, barking deer Muntiacus muntjac and large bovids were 7.5, 3.5 and 3.0 km−2, respectively. When female home range size and prey abundance were compared at six locations in Thailand, and at other sites in India, Nepal, Bangladesh and Russia, a significant negative correlation was found between prey abundance and home range size. Monitoring this relationship can provide managers with metrics for setting conservation goals.

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Home range of the swamp wallaby, Wallabia bicolor

Wildlife Research ◽

10.1071/wr9930571 ◽

1993 ◽

Vol 20 (5) ◽

pp. 571 ◽

Cited By ~ 16

Author(s):

S Troy ◽

G Coulson

Keyword(s):

Home Range ◽

Home Range Size ◽

Range Size ◽

Home Ranges ◽

Convex Polygons ◽

Minimum Convex Polygon ◽

Eucalypt Forest ◽

Significant Difference ◽

Wallabia Bicolor ◽

Swamp Wallaby

Home range in the swamp wallaby, Wallabia bicolor (Marsupialia : Macropodoidea) was examined using radio-tracking in a 150-ha remnant of mixed eucalypt forest at Healesville, Victoria. Three methods were used to calculate home-range size: minimum convex polygons, fourier transform MAP(O.95) and MAP(0.50) estimation, and harmonic mean 50% isopleths and 95% isopleths. The minimum convex polygon method produced the largest estimate of home-range area (16.01 +/-.45 ha). Each method required a different number of fixes before home-range area estimates reached an asymptote. These data showed that W. bicolor have small, overlapping home ranges and that the shape of the home range varied between individuals. Home-range area was larger than previously reported for this species, and there was no significant difference between the sexes in home-range size.

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Home range of stoats (Mustela erminea) in podocarp forest, south Westland, New Zealand: implications for a control strategy

Wildlife Research ◽

10.1071/wr00001 ◽

2001 ◽

Vol 28 (2) ◽

pp. 165 ◽

Cited By ~ 6

Author(s):

Craig Miller ◽

Mike Elliot ◽

Nic Alterio

Keyword(s):

New Zealand ◽

Home Range ◽

Breeding Season ◽

Convex Polygon ◽

Home Ranges ◽

Convex Polygons ◽

Minimum Convex Polygon ◽

Mustela Erminea ◽

The Mean ◽

Breeding Seasons

The home range of stoats (Mustela erminea) was determined as part of a programme to protect Okarito brown kiwi chicks (Apteryx australis) ‘Okarito’, from predation. Twenty-seven stoats were fitted with radio-transmitters and tracked in two podocarp (Podocarpaceae) forests, in south Westland, New Zealand, from July 1997 to May 1998. Home-range area was determined for 19 animals by minimum convex polygons and restricted-edge polygons, and core areas were determined by hierarchical cluster analysis. The mean home ranges of males across all seasons calculated by minimum convex polygon (210 28 ha ( s.e.)) and restricted-edge polygon (176 29 ha) were significantly larger than those of females across all seasons (89 14 ha and 82 12 ha). The mean home range of males calculated by minimum convex polygon during the breeding season (256 38 ha) was significantly larger than the mean home range pooled across the non-breeding seasons (149 16 ha), whereas that calculated by restricted-edge polygon was not significantly different. The mean home range of females during the breeding season was not significantly different from that in the non-breeding seasons when estimated by either method. Overlap of home ranges was observed within and between sexes in all seasons, with the greatest proportion of home range overlap being male–female. The mean home range of females in spring and summer is used to guide the spacing of control stations.

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Movement patterns of feral predators in an arid environment – implications for control through poison baiting

Wildlife Research ◽

10.1071/wr08098 ◽

2009 ◽

Vol 36 (5) ◽

pp. 422 ◽

Cited By ~ 64

Author(s):

K. E. Moseby ◽

J. Stott ◽

H. Crisp

Keyword(s):

Home Range ◽

Sand Dunes ◽

Activity Patterns ◽

Movement Patterns ◽

Home Range Size ◽

Range Size ◽

Home Ranges ◽

Feral Cats ◽

Poison Baiting ◽

Specific Variation

Control of introduced predators is critical to both protection and successful reintroduction of threatened prey species. Efficiency of control is improved if it takes into account habitat use, home range and the activity patterns of the predator. These characteristics were studied in feral cats (Felis catus) and red foxes (Vulpes vulpes) in arid South Australia, and results are used to suggest improvements in control methods. In addition, mortality and movement patterns of cats before and after a poison-baiting event were compared. Thirteen cats and four foxes were successfully fitted with GPS data-logger radio-collars and tracked 4-hourly for several months. High intra-specific variation in cat home-range size was recorded, with 95% minimum convex polygon (MCP) home ranges varying from 0.5 km2 to 132 km2. Cat home-range size was not significantly different from that of foxes, nor was there a significant difference related to sex or age. Cats preferred habitat types that support thicker vegetation cover, including creeklines and sand dunes, whereas foxes preferred sand dunes. Cats used temporary focal points (areas used intensively over short time periods and then vacated) for periods of up to 2 weeks and continually moved throughout their home range. Aerial baiting at a density of 10 baits per km2 was ineffective for cats because similar high mortality rates were recorded for cats in both baited and unbaited areas. Mortality was highest in young male cats. Long-range movements of up to 45 km in 2 days were recorded in male feral cats and movement into the baited zone occurred within 2 days of baiting. Movement patterns of radio-collared animals and inferred bait detection distances were used to suggest optimum baiting densities of ~30 baits per km2 for feral cats and 5 per km2 for foxes. Feral cats exhibited much higher intra-specific variation in activity patterns and home-range size than did foxes, rendering them a potentially difficult species to control by a single method. Control of cats and foxes in arid Australia should target habitats with thick vegetation cover and aerial baiting should ideally occur over areas of several thousand square kilometres because of large home ranges and long-range movements increasing the chance of fast reinvasion. The use of temporary focal points suggested that it may take several days or even weeks for a cat to encounter a fixed trap site within their home range, whereas foxes should encounter them more quickly as they move further each day although they have a similar home-range size. Because of high intra-specific variability in activity patterns and home-range size, control of feral cats in inland Australia may be best achieved through a combination of control techniques.

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Ecological Correlates of Fecal Corticosterone Metabolites in Female Greater Sage-Grouse (Centrococercus urophasianus)

Canadian Journal of Zoology ◽

10.1139/cjz-2020-0258 ◽

2021 ◽

Author(s):

Jordan Clark Rabon ◽

Cassandra M. V. Nuñez ◽

Peter Coates ◽

Mark Ricca ◽

Tracey N. Johnson

Keyword(s):

Home Range ◽

Stress Responses ◽

Habitat Degradation ◽

Home Range Size ◽

Range Size ◽

Home Ranges ◽

Remotely Sensed Data ◽

Sage Grouse ◽

Ecological Conditions ◽

Annual Grasses

Measurement of physiological responses can reveal effects of ecological conditions on an animal and correlate with demographic parameters. Ecological conditions for many animal species have deteriorated as a function of invasive plants and habitat fragmentation. Expansion of juniper (Juniperus spp.) trees and invasion of annual grasses into sagebrush (Artemisia spp.) ecosystems have contributed to habitat degradation for Greater Sage-Grouse (Centrococercus urophasianus (Bonaparte, 1827); hereafter, “Sage-Grouse”), a species of conservation concern throughout its range. We evaluated relationships between habitat use in a landscape modified by juniper expansion and annual grasses and corticosterone metabolite levels (stress responses) in feces (FCORTm) of female Sage-Grouse. We used remotely sensed data to estimate vegetation cover within hens’ home ranges and accounted for factors that influence FCORTm in other vertebrates, such as age and weather. We collected 36 fecal samples from 22 radio-collared hens during the brood-rearing season (24 May–26 July) in southwestern Idaho 2017–18. Concentrations of corticosterone increased with home range size but decreased with reproductive effort and temperature. The importance of home range size suggests that maintaining or improving habitats that promote smaller home ranges would likely facilitate a lower stress response by hens, which should benefit Sage-Grouse survival and reproduction.

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Home Ranges and Movements of Elk (Cervus canadensis) Restored to Southern Ontario, Canada

The Canadian Field-Naturalist ◽

10.22621/cfn.v130i4.1926 ◽

2017 ◽

Vol 130 (4) ◽

pp. 320 ◽

Cited By ~ 2

Author(s):

Rick Rosatte

Keyword(s):

Home Range ◽

Home Range Size ◽

Home Ranges ◽

Winter Range ◽

The Social ◽

Cervus Canadensis ◽

Summer Range ◽

Seasonal Basis ◽

Social Units ◽

Winter Feeding

During 2000 and 2001, Elk (Cervus canadensis) were restored to the Bancroft, Ontario area. The objective of this study was to determine the home range and movements of six social units of Elk, 5–12 years after restoration, in an area of about 2500 km2 near Bancroft. Home range and movements were calculated from 40 221 Global Positioning System locations acquired from 56 collared Elk (16 bulls and 40 cows) between 2006 and 2013. Annual home ranges were found to be significantly greater (mean 110.3 km2, standard error [SE] 11.2) for Elk in areas where winter feeding by humans did not occur compared with those (mean 51.0 km2, SE 9.0) where winter feeding was prevalent. Elk in winter feeding areas had smaller ranges in winter than other seasons. On a seasonal basis, home range size was larger for Elk in areas where winter feeding did not occur; mean winter home range for Elk in non-feeding areas was 73.4 km2 (SE34.0) compared with 8.3 km2 (SE 2.6) for Elk in areas where winter feeding occurred. The 20 Elk that were monitored for multiple years exhibited home range fidelity among years. The entire range of all radio-collared Elk within the social groups studied covered 1716.4 km2 during 2006–2013. Average daily movements of Elk in the study arearanged from 1.0 to 2.1 km/day with greatest movements occurring during spring and summer. However, some Elk were capable of moving an average of 5–7km in a 12-h interval. Movements (about 5 km) to winter range occurred during October to December each year. Cows moved to calving areas in May with mean movements of Elk to spring/summer range about 6 km. Cow/calf groups moved to fall ranges by early September with mean movements of about 4 km. During the rut, mean bull movements of 16.0 km to cow groups over 1–5 days occurred in early September. Hunting of Elk during the fall of 2011 and 2012 did not appear to significantly affect the movements and dispersion of Elk in the study area.

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Allometry of home range size in lake and river fishes

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f95-144 ◽

1995 ◽

Vol 52 (7) ◽

pp. 1499-1508 ◽

Cited By ~ 159

Author(s):

Charles K. Minns

Keyword(s):

Body Size ◽

Home Range ◽

Freshwater Fish ◽

Fish Population ◽

Home Range Size ◽

Range Size ◽

Territory Size ◽

Home Ranges ◽

Data Set ◽

Terrestrial Mammals

A data set assembled from published literature supported the hypotheses that (i) home range size increases allometrically with body size in temperate freshwater fishes, and (ii) fish home ranges are larger in lakes than rivers. The allometric model fitted was home range = A∙(body size)B. Home ranges in lakes were 19–23 times larger than those in rivers. Additional analyses showed that membership in different taxonomic groupings of fish, the presence–absence of piscivory, the method of measuring home range, and the latitude position of the water bodies were not significant predictive factors. Home ranges of freshwater fish were smaller than those of terrestrial mammals, birds, and lizards. Home ranges were larger than area per fish values derived by inverting fish population and assemblage density–size relationships from lakes and rivers and territory–size relationships in stream salmonids. The weight exponent (B) of fish home range was lower than values reported for other vertebrates, 0.58 versus a range of 0.96–1.14. Lake–river home range differences were consistent with differences reported in allometric models of freshwater fish density and production.

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