Effects of Land Use and Wildfires on the Habitat Selection of Great Bustard (Otis tarda l.)-Implications for Species Conservation

2016 ◽  
Vol 27 (4) ◽  
pp. 910-918 ◽  
Author(s):  
Zsolt Végvári ◽  
Orsolya Valkó ◽  
Balázs Deák ◽  
Péter Török ◽  
Sándor Konyhás ◽  
...  
2012 ◽  
Vol 23 (3) ◽  
pp. 323-336 ◽  
Author(s):  
PEDRO ROCHA ◽  
MANUEL B. MORALES ◽  
FRANCISCO MOREIRA

SummaryWe present results on breeding parameters, nesting performance and nest habitat selection of the globally threatened Great Bustard Otis tarda, gathered during a 3-year study in Castro Verde (southern Portugal). A total of 107 nests were located. The estimated average onset of laying was 22 April (SD = 12 days, n = 8). The incubation period ranged from 25 March to 15 June. Nearly 95% of females incubated between 1 April and 31 May. Mean clutch size was 2.12 (SD = 0.69, n = 86), showing no significant inter-annual differences. There was no significant relationship between clutch size and average nest finding date, although, on average, nests were found later each year. Hatching occurred between 21 April and 26 June. The estimated proportion of eggs hatched per nest (hatching percentage) was 87.5% in 2002 (n = 8), 64.0% in 2003 (n = 33) and 75.8% in 2004 (n = 33). Overall nesting success for the three years was 71% (n = 107). The main causes of nesting failure were agricultural activities, mainly ploughing and harvesting, followed by corvid predation. Nests were spatially aggregated up to 800–1,500 m. At larger scales, the spatial distribution of nests can be considered random or uniform. Females showed a clear preference for nesting in cereal fields, followed by young fallows, old fallows, ploughed fields and then other habitats, although the intensity of selection of particular habitats varied between years. Nests were associated with both cereals and fallows, thus aggregating where those habitat types occurred within the study area. These results provide the first complete description of the nesting process in a Great Bustard population, as well as important cues to the assessment of conservation measures implemented in Castro Verde, an area holding around 80% of the Portuguese population of this species (application of EU agri-environmental schemes, power line signalling, water-point provision in dry years).


2001 ◽  
Vol 12 (1) ◽  
pp. 19-33 ◽  
Author(s):  
Joachim Hellmich ◽  
Youssef Idaghdour

The Moroccan population of Great Bustard Otis tarda was surveyed in the four years 1998–2001. Highest numbers were counted in December 1998 (21 males, 62–65 females, four first-year males: total c. 90) and March 2001 (15 males, 60–66 females, four first-year males: total 75–81). Combining enquiry results from local people with these data, the population size for spring is estimated at 92–111 individuals, and 117–133 for winter. Reproduction is confirmed. Threats to the population include illegal hunting, habitat loss through agricultural intensification (irrigation, use of pesticides) and infrastructural changes (construction of a motorway and a powerplant), disturbance, and accidents at powerlines and antennas. Several conservation measures are suggested: cease hunting; maximize the attention given to display sites; encourage villagers to carry out “Great Bustard-friendly” land use and adapt animal stocks to the carrying capacity of their regions; clarify the situation of genetic exchange between Spanish and Moroccan populations; study movements between the Moroccan sites; monitor the size and trends of the most important subpopulations; and conduct education campaigns in schools and increase public awareness among adults.


2021 ◽  
Vol 107 (3) ◽  
pp. 147-172
Author(s):  
David C. Stoner ◽  
Mark A. Ditmer ◽  
Dustin L. Mitchell ◽  
Julie K. Young ◽  
Michael L. Wolfe

Western North America is experiencing remarkable human population growth and land-use change. Irrigation and associated cultivation have led to colonization of urban-wildland interface (UWI) environments by mule deer (Odocoileus hemionus), and consequently, cougars (Puma concolor). In the wake of these changes, human-wildlife conflicts have increased in tandem with questions about long-term species conservation. To address these concerns, we fit 79 cougars with radio-telemetry collars in the Oquirrh Mountains near Salt Lake City, Utah (2002–2010). Our goal was to evaluate variation in cougar habitat selection, diet, and cause-specific mortality in a landscape dominated by urban, military, and industrial activities. We used radio-telemetry data in concert with Resource Selection Functions to address three hypotheses: (1) that cougars would select wildland over UWI land-uses; (2) prey composition would reflect differences in land-use; and (3) mortality would be predominantly human-caused. Cougars largely selected wildland habitats associated with seasonal mule deer presence, but contrary to expectation, they also selected habitats closer to urban and mined areas. Prey composition in the UWI did not differ from wildland habitats. Domestic ungulates represented only 2% of 540 recovered prey items and were found primarily in wildlands. Native ungulates comprised > 90% of the total kill, irrespective of season or land-use, suggesting that use of UWI habitats was linked to mule deer presence. Cougar mortality was disproportionately due to natural causes in wildlands, but individuals that died of human causes in UWI habitats were more likely to be inexperienced hunters, supporting young kittens, or compromised by physical handicaps. In general, presence of mule deer was the key predictor of cougar habitat use, even in this highly disturbed, anthropogenically altered landscape. As such, management designed to reduce conflict and ensure conservation will need to focus on urban deer, land-use planning, and targeted education campaigns to reduce food subsidies.


2004 ◽  
Vol 10 (1) ◽  
pp. 251-260 ◽  
Author(s):  
Francisco Moreira ◽  
Rui Morgado ◽  
Stephen Arthur

2013 ◽  
Vol 24 (1) ◽  
pp. 32-44 ◽  
Author(s):  
ROBERT J. BURNSIDE ◽  
ZSOLT VÉGVÁRI ◽  
RICHARD JAMES ◽  
SANDOR KONYHÁS ◽  
GÁBOR KOVÁCS ◽  
...  

SummaryUnderstanding habitat selection and assessing habitat quality have an important role in habitat management and prioritisation of areas for protection. However, interpretations of habitat selection and habitat quality can be confounded by social effects such as conspecific attraction. Using 7 years’ data from a well monitored Great Bustard Otis tarda population in Central Europe, we investigated the roles of human disturbance and social cues in display site selection of male Great Bustards Otis tarda. The spatial distribution of displaying males was best predicted by human disturbance. In addition, the number of males attending display sites was strongly correlated to the number of females present and not with disturbance. This suggests that abundance could be a misleading metric for habitat quality in social species. Our results highlight the roles of disturbance and social cues in male habitat choice, and suggest that social factors need to be taken into consideration for management of endangered populations.


2013 ◽  
Vol 60 (1) ◽  
pp. 69-76 ◽  
Author(s):  
Unni Støbet Lande ◽  
Leif Egil Loe ◽  
Ole Johan Skjærli ◽  
Erling L. Meisingset ◽  
Atle Mysterud

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