One of the principal goals of the Iberian lynx LIFE conservation project is to initiate the first... more One of the principal goals of the Iberian lynx LIFE conservation project is to initiate the first reintroduction of the species in recently extinct nuclei. The previous work to select the best area for the reintroduction of the Iberian lynx in Andalusia began in 2005. The two selected areas to perform the reintroduction into are :Guadalmellato and Guarrizas valleys, both areas showing optimal habitat structure and resources abundance. A brief abstract of the previous works and a planning of the future steps in the Iberian lynx reintroduction are presented in this communication.
Hystrix-italian Journal of Mammalogy, Dec 20, 2002
Information regarding spatio-temporal relationships and encounters of sympatric domestic sheep, A... more Information regarding spatio-temporal relationships and encounters of sympatric domestic sheep, Alpine ibex (Cupru ibex ibex) and Alpine chamois (Rupicupru rupicupru rupicupru) in the Swiss Alps were systematically registered to evaluate the possibility of an interspecific transmission of infectious agents on pastures. Observations were performed in alpine regions of four Swiss cantons during the 1997 and 1998 mountain summer grazing season. In the main study area, Val Chamuera (canton of Grisons), a consistent reduction in the number of ibexes was observed after the arrival of sheep on the pasture. Some ibexes remained for a longer time in the area, but in general, ibexes and sheep did not use the same compartments of the area simultaneously. However, a salt lick for sheep attracted the ibexes, and several encounters were recorded in the compartments close to this salt lick. Several encounters registered in other areas of the Swiss Alps also occurred in the neighbourhood of a salt lick; however, in other cases different species were attracted by rich pastures. The study indicates that encounters (0-50 m) between free-ranging individuals of different Caprinae species, domestic and wild, are not uncommon events in the Alps. Therefore, encounters can be considered to be a predisposing factor for interspecific transmission of infectious agents such as Mycoplusrnu conjunctivae, causing keratoconjunctivitis in chamois, ibex, domestic sheep and goats.
This table contains the predations risk values (based on a lynx resource selection function) of t... more This table contains the predations risk values (based on a lynx resource selection function) of the 5487 lynx locations that occurred during the night (sun angle <=0) used in Gehr et al. 2018 (Behavioral Ecology). For information on the raw data or for R-code used to calculate the predation risk please contact the data owner
This table contains the predations risk values (based on a lynx resource selection function) of t... more This table contains the predations risk values (based on a lynx resource selection function) of the 41569 random locations drawn within lynx home ranges used in Gehr et al. 2018 (Behavioral Ecology). Predation risk was calculated for midnight. For information on the raw data or for R-code used to calculate the predation risk please contact the data owner
This table contains the mortality data of 65 collared deer used to build the cox proportional haz... more This table contains the mortality data of 65 collared deer used to build the cox proportional hazard model in Gehr et al. 2018 (Behavioral Ecology). The column nr_days refers to the number of days a deer was monitored whereas entry_day and exit_day refer to the day the animal entered or left the study relative to the starting date of the study (30 November 2011). Fate refers to the fate of the animal (1 indicates died of non-lynx related causes, 0 indicates either alive at the end of monitoring or killed by lynx). Mort_cause refers to the cause of mortality. The code for mortalities: 2=disease/starvation, 3=road kill, 6=lynx kill, 7=dog kill, 10=hunting, 11=unknown. Human_risk refers to the mean human disturbance index value for all locations for each deer (composite of house density and distance to the closes road). Mean alti refers to the mean altitude of all locations for each deer. Mean_pr refers to the mean predation risk value (based on a lynx resource selection function) of all locations of each deer. Human_risk, mean_alti and mean_pr need to be scaled (mean=0 and SD=1) for the survival model
Data from: Evidence for nonconsumptive effects from a large predator in an ungulate prey?
Pedators can indirectly affect prey survival and reproduction by evoking costly anti-predator res... more Pedators can indirectly affect prey survival and reproduction by evoking costly anti-predator responses. Such non-consumptive effects may be as strong or stronger than consumptive predator effects. However, evidence for this in large terrestrial vertebrate systems is equivocal and few studies quantify the actual fitness costs of non-consumptive effects. Here we investigated whether non-consumptive effects elicited by Eurasian lynx (Lynx lynx), a large terrestrial predator, reduced survival in an ungulate prey, the European roe deer (Capreolus capreolus). To reveal the behavioral processes underlying non-consumptive effects, we distinguished between proactive risk avoidance of areas with high lynx encounter probability, and reactive risk avoidance in response to actual lynx encounters and analyzed these responses using step selection functions. We also quantified the consequences of these behaviors for deer survival. Deer reacted differently at day and at night, but avoided high-risk areas proactively during the day and at night in the summer. During a predator encounter, deer increased avoidance of high-risk areas at night but not during the day. Thus, roe deer exhibited a behavioral response race that involved temporally and spatially varying tradeoffs with environmental constraints. We found evidence that non-consumptive effects of lynx predation risk reduced deer survival and that survival was more sensitive to variation in non-consumptive effects of lynx than to variation in human proximity. Our findings highlight that non-consumptive effects may depend on the spatiotemporal distribution of risks and the environmental context, and we discuss how human factors contribute to predator-prey dynamics in human dominated landscapes
This table contains the GPS locations of roe deer associated with habitat variables and temporal ... more This table contains the GPS locations of roe deer associated with habitat variables and temporal variables that were used to build a habitat model (RSF) for roe deer. The table is divided into used (actual) deer locations and random locations (loc_id=NA) in a ratio of 1:10 (column "use"). The table also includes an animal id. Swisstopo in the column headers refers to the source of the environmental variables. Cover swisstopo is a dummy variable for open/cover. Slope_sq and altitude_sq are the squared slope and altitude variables. Aspect swisstopoS is the southern exposition. Hum_indx is a composite of road_dist and house density. The 8 temporal variables are time harmonics of a Fourier transform for time of day (tsin, tcos, tsin2, tcos2; period of 24) and day of year(ytsin, ytcos, ytsin2, ytcos2; period of 365) All continuous variables in this table are mean centered and standardized to a SD=1. For information on the raw data or for R-code used to run the models please contact the data owner
This table contains the GPS locations of lynx associated with habitat variables and temporal vari... more This table contains the GPS locations of lynx associated with habitat variables and temporal variables that were used to build a logistic regression modelling the proportion of time lynx spend active. The data in this table refers to the no hunting model in Gehr et al. 2017 (Ecology and Evolution). This table differs from the all data table in that all locations during the 10 week hunting season were removed. The data was restricted to locations between the beginning of astronomical twilight in the morning (sun angle < 18 degrees below the horizon) and the end of astronomical twilight in the evening (sun angle > 18 degrees below the horizon). Hence, to repeat the model in Gehr et al. 2017 (Ecology and Evolution) the data with sun angle <= -18 degrees have to be removed. For the model used to create Figure S4 in the Appendix S1 the complementary dataset has to be used. The table is divided into locations assigned to an active or inactive behavioral state (column “active” is a dummy variable - 1=active/0=inactive). Swisstopo in the column headers refers to the source of the environmental variables. Cover swisstopo is a dummy variable for open/cover. Edge_dist_swisstopo refers to the distance to the closest forest edge. Slope_sq and altitude_sq are the squared slope and altitude variables. Aspect_swisstopoS is the southern exposition. Cover_edge refers to an interaction term between cover_swisstopo and edge_dist_swisstopo. House_road_dist_small refers to an interaction between house_density and road_dist_small. The 6 temporal variables are time harmonics of a Fourier transform for time of day (tsin, tcos; period of 24) and day of year (ytsin, ytcos, ytsin2, ytcos2; period of 365). All habitat variables were measured at the end of a step. All continuous variables in this table are mean centered and standardized to a SD=1. For information on the raw data or for R-code used to run the models please contact the data owner
Human related mortality is a major threat for large carnivores all over the world and there is in... more Human related mortality is a major threat for large carnivores all over the world and there is increasing evidence that large predators respond to human related risks in a similar way as prey respond to predation risk. This insight recently led to the conceptual development of a landscape of coexistence that can be used to identify areas which can sustain large predator populations in human dominated landscapes. In this study we applied the landscape of coexistence concept to a large predator in Europe. We investigated to what extent Eurasian lynx Lynx lynx habitat selection is affected by human disturbance in a human dominated landscape. More specifically, we were interested in the existence of a tradeoff between the availability of roe deer, one of their main prey and avoidance of human disturbance and how this affects the spatiotemporal space use patterns of lynx. We found that lynx face a tradeoff between high prey availability and avoidance of human disturbance and that they respond to this by using areas of high prey availability (but also high human disturbance) during the night when human activity is low. Furthermore our analysis showed that lynx increase their travelling speed and remain more in cover when they are close to areas of high human disturbance. Despite clear behavioral adjustments in response to human presence, prey availability still proved to be the most important predictor of lynx occurrence at small spatial scale, whereas human disturbance was considerably less important. The results of our study demonstrate how spatio-temporal adaptations in habitat selection enable large carnivores to persist in human dominated landscapes and demonstrate the usefulness of the concept of a landscape of coexistence to develop adaptive management plans for endangered populations of large carnivores.
Predator diet composition and kill rates have to be known in order to quantify predation pressure... more Predator diet composition and kill rates have to be known in order to quantify predation pressure on prey populations. While ground-truthing of GPS location clusters (GLCs) is a reliable method for finding large-and medium-sized prey items, finding the remains of small prey is still considered a major difficulty. In this study, we searched GLCs of Eurasian lynx Lynx lynx in the Northwestern Swiss Alps in order to determine if GLC analysis is a suitable method for detecting kill sites of newborn ungulates and other small prey animals. Juvenile ungulates made up 26% of the prey spectrum and 17% total consumed biomass (TCB), while hares, marmots, and red foxes accounted for 25% of all found prey items (8% TCB). Lynx spent significantly more time in GLCs containing large prey, but no clear transition in GLC duration for distinguishing between large (≥ 10 kg; mean duration = 46.9 h, SD = 30.1 h) and small prey (< 10 kg; mean duration = 26.7 h, SD = 21.1 h) could be defined. We explored the influence of different cutoff values for GLC duration on lynx diet composition. GLCs with a duration of < 9 h had less than 25% detection success, but still contained 13% of all small prey items. We conclude that GLC analysis is a promising tool for exploring predation on newborn ungulates, mesopredators, and other smaller prey animals weighing between 2 and 10 kg. However, substantial field effort is mandatory to sufficiently detect prey remains in short-lasting GLCs.
Between March and December 1999, five free-ranging lynx (Lynx lynx) affected by mange were found ... more Between March and December 1999, five free-ranging lynx (Lynx lynx) affected by mange were found dead or shot by game wardens in the Swiss Alps. In the first two cases, Notoedres cati was isolated from the skin; in the third and fourth case, Sarcoptes scabiei was the cause of the infection; and in the fifth case, a mixed infection was diagnosed. Red foxes (Vulpes vulpes) affected with sarcoptic mange and domestic cats infested with N. cati are likely to be the sources of infection. It seems improbable that mange will occur as an epidemic in lynx in Switzerland, but losses due to infections with N. cati and/or S. scabiei may have an impact on this small, geographically limited lynx population. This is the first report of notoedric mange in a free-ranging lynx and the first report of mange in lynx from Switzerland.
. Characterisation of Eurasian lynx Lynx lynx den sites and kitten survival. Wildlife Biology 13,... more . Characterisation of Eurasian lynx Lynx lynx den sites and kitten survival. Wildlife Biology 13, 417-429. Keywords: 8CH/Alps/den site/Jura/lynx/Lynx lynx/survival We retrospectively investigated characteristics of den structures and den sites used by female Eurasian lynx Lynx lynx in the Jura Mountains and the northwestern Alps of Switzerland. During 1983-2000, we discovered 30 natal and 40 maternal dens belonging to 26 females. Important den structures were closed, i.e. provided good shelter, had few entrances, and measured 1 m2. Dens were found in rocky places, caves and wooden surroundings. Most dens were located in mixed forests with relatively open vegetation allowing for a visibility of 10-20 m. Contrary to our expectations, natal and maternal dens were equally exposed to human disturbance and were found in terrain which could be dangerous for the kittens. Overall, the two den types barely differed. While concealment did not seem to play a very important part at natal dens and while natal dens were almost never open structures, maternal dens were surrounded by a large number of hiding places and the dens and surroundings were rich in visual contrasts providing good camouflage options. Dens in the Alps and in the Jura Mountains were located in steeper terrain than available on average. The quality of the den sites did not seem to affect the survival of young lynx. Well-suited den sites are so abundant in the Alps and the Jura Mountains that females obviously have no problems finding good den sites. Breitenmoser, U. 2007: Characterisation of Eurasian lynx Lynx lynx den sites and kitten survival. -Wildl. Biol. 13: 417-429. We retrospectively investigated characteristics of den structures and den sites used by female Eurasian lynx Lynx lynx in the Jura Mountains and the northwestern Alps of Switzerland. During 1983-2000, we discovered 30 natal and 40 maternal dens belonging to 26 females. Important den structures were closed, i.e. provided good shelter, had few entrances, and measured 1 m 2 . Dens were found in rocky places, caves and wooden surroundings. Most dens were located in mixed forests with relatively open vegetation allowing for a visibility of 10-20 m. Contrary to our expectations, natal and maternal dens were equally exposed to human disturbance and were found in terrain which could be dangerous for the kittens. Overall, the two den types barely differed. While concealment did not seem to play a very important part at natal dens and while natal dens were almost never open structures, maternal dens were surrounded by a large number of hiding places and the dens and surroundings were rich in visual contrasts providing good camouflage options. Dens in the Alps and in the Jura Mountains were located in steeper terrain than available on average. The quality of the den sites did not seem to affect the survival of young lynx. Well-suited den sites are so abundant in the Alps and the Jura Mountains that females obviously have no problems finding good den sites.
Variation in diet, prey selectivity and home-range size of Eurasian lynx Lynx lynx in Switzerland... more Variation in diet, prey selectivity and home-range size of Eurasian lynx Lynx lynx in Switzerland. Wildlife Biology 13, 393-405.
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