scholarly journals Using GPS tracking and stable multi-isotopes for estimating habitat use and winter range in Palearctic ospreys

Oecologia ◽  
2021 ◽  
Author(s):  
Flavio Monti ◽  
Aloїs Robert ◽  
Jean-Marie Dominici ◽  
Andrea Sforzi ◽  
Rafel Triay Bagur ◽  
...  

AbstractWe used both satellite tracking and carbon, nitrogen and sulphur stable isotopic analysis (SIA) to infer wintering ecology and habitat use of the Corsican osprey Pandion haliaetus population. A control sample of feathers from 75 individuals was collected within the osprey’s northern hemisphere breeding range, to assess the SIA variability across habitat types. An experimental set of SIA on feathers of 18 Corsican adults was examined to infer wintering ground locations and habitat types used during the non-breeding period. We calibrated the SIA using GPS/GSM tracks of 12 Mediterranean adults’ movements as wintering site references. We found 50% of individuals were resident and the other half migrated. Ospreys spent the winter at temperate latitudes and showed a high plasticity in habitat selection spread over the Mediterranean basin (marine bays, coastal lagoons/marshland, inland freshwater sites). Complementary to GPS tracking, SIA is, at a broad geographical scale, a reliable method to determine whether ospreys overwinter in a habitat different from that of their breeding area. This study proved that the integration of SIA and GPS/GSM tracking techniques was effective at overcoming the intrinsic limits of each method and achieving greater information for basic ecological studies of migratory birds in aquatic environments.

2020 ◽  
Vol 89 (2) ◽  
Author(s):  
Bruno Santucci ◽  
Andrea Pulvirenti ◽  
Samuele Ramellini ◽  
Marinella Miglio

Most studies focusing on Rock Sparrow populations concern their breeding biology. With this study, we aim to investigate the wintering habitat and social behaviour outside the breeding period. In the study area the species is present all year long, and, outside the breeding period, birds frequently gather together on flocks of different size (3-150 individuals), which are larger in the coldest months. The habitat types most used by the species were cereal fields with crops in their first stage of development (17.71% ± 4.72 Standard Deviation) and arable stubbles, both of them with bushes and trees on their boundaries (82.4%), which likely provide shelters from predators. The bird species most frequently associated with Rock Sparrow flocks were Tree Sparrow, Starling and Crested Lark. Holes in the roof tiles of the same abandoned buildings used for breeding were also used as night shelters. The average hours of leaving and returning to the shelters was strictly related to the photoperiod (rs = -0.9405; 0.8810).


2014 ◽  
Vol 128 (3) ◽  
pp. 272 ◽  
Author(s):  
Gilbert Proulx

Late-winter habitat use by the Fisher, Pekania pennanti (Erxleben, 1777) in northwestern Saskatchewan was assessed in February 2009, 2011, and 2012. A total of 78 Fisher tracks were recorded over 60 300 m of snowshoe surveys. Fisher tracks were significantly less frequent than expected in Tamarack (Larix laricina [Du Roi] K. Koch) stands with > 40% crown closure and mainly 0–10 m trees (P < 0.05) and in open areas. Fishers used other habitat types equal to availability, including muskeg and coniferous, mixed, and deciduous forest stands. Maintaining mosaics of forest stands of different seral stages interspersed with muskeg would meet the late-winter habitat needs of Fishers in the Boreal Plains Ecozone of northwestern Saskatchewan.


Author(s):  
Véronique Dubos ◽  
André St-Hilaire ◽  
Normand E Bergeron

Arctic char is a fish species known to occupy diverse habitats within the Arctic region. However, summer habitat use during the juvenile stage of the anadromous form is largely unknown. The present study aims to characterize fry and parr summer habitat preferences. Surveys were conducted by electrofishing, associated with physical habitat characterization on several rivers of the Ungava Bay, Nunavik, Canada. At the microhabitat and station scales, fry showed significant habitat preferences for shallow water and slow velocity. At the mesohabitat scale, fry showed a significant habitat selectivity for riffles. This habitat selectivity implies that habitat models can be built to evaluate the potential of habitat suitability for Arctic char fry. However, no significant habitat selectivity was found for parr. Parr size was nonetheless positively correlated with velocity, which was found to be a limitative factor for juvenile habitat use. This first attempt at modeling juvenile anadromous Arctic char habitat in rivers emphasizes the importance of selecting an appropriate spatial scale and reiterates the fact that parr showed relatively high plasticity in stream habitat selection.


2021 ◽  
Author(s):  
yang teng ◽  
Shupei TANG ◽  
lai heda meng ◽  
Liji Wu ◽  
Zhiqing HAN ◽  
...  

Abstract Home range size estimation is a crucial basis for developing effective conservation strategies and provides important insights into animal behavior and ecology. This study aimed at analyzing the home range variations, the influence of altitude in habitat selection, and comparing three methods in home range estimation of Chinese gorals (Naemorhedus griseus) living at a cliff landscape. The results indicated that there were significant differences between the annual home range sizes of individual animals but there was no difference in their seasonal home range sizes based on GPS tracking data of five female Chinese gorals from February 2015 to September 2018. The monthly home ranges decreased dramatically in May, June and July due to birth-giving. Notable seasonal variations were found in the micro-habitats of the Chinese gorals, as reflected by the altitude they inhabit, with higher altitude habitats used in spring and lower altitude habitats used in winter. Additionally, the altitude of monthly habitats was lowest in January, which may indicate an adaptation to low air temperature. We also found differences between estimation methods, namely minimum convex polygon (MCP), kernel density estimation (KDE) and α-local convex hull (α-LoCoH), with seasonal home range sizes derived from α-LoCoH being substantially smaller than those derived from MCP and KDE. In conclusion, our findings filled the gaps in home range study for this endangered species and contributed to effective conservation strategies. Considerations shall have to be given to the variations in home range estimation caused by different methods when dealing with rugged habitats, so as to make sure that any interpretation concerning the habitat use of the targeted species made on basis of such results would be meaningful and valid.


2021 ◽  
Author(s):  
Yang Teng ◽  
Shupei TANG ◽  
Dalai Menghe ◽  
Liji Wu ◽  
Zhiqing HAN ◽  
...  

Abstract Home range size estimation is a crucial basis for developing effective conservation strategies and provides important insights into animal behavior and ecology. This study aimed at analyzing the home range variations, the influence of altitude in habitat selection, and comparing three methods in home range estimation of Chinese gorals (Naemorhedus griseus) living at a cliff landscape. The results indicated that there were significant differences between the annual home range sizes of individual animals but there was no difference in their seasonal home range sizes based on GPS tracking data of five female Chinese gorals from February 2015 to September 2018. The monthly home ranges decreased dramatically in May, June and July due to birth-giving. Notable seasonal variations were found in the micro-habitats of the Chinese gorals, as reflected by the altitude they inhabit, with higher altitude habitats used in spring and lower altitude habitats used in winter. Additionally, the altitude of monthly habitats was lowest in January, which may indicate an adaptation to low air temperature. We also found differences between estimation methods, namely minimum convex polygon (MCP), kernel density estimation (KDE) and α-local convex hull (α-LoCoH), with seasonal home range sizes derived from α-LoCoH being substantially smaller than those derived from MCP and KDE. In conclusion, our findings filled the gaps in home range study for this endangered species and contributed to effective conservation strategies. Considerations shall have to be given to the variations in home range estimation caused by different methods when dealing with rugged habitats, so as to make sure that any interpretation concerning the habitat use of the targeted species made on basis of such results would be meaningful and valid.


2011 ◽  
Vol 278 (1723) ◽  
pp. 3437-3443 ◽  
Author(s):  
Colin E. Studds ◽  
Peter P. Marra

Climatic warming has intensified selection for earlier reproduction in many organisms, but potential constraints imposed by climate change outside the breeding period have received little attention. Migratory birds provide an ideal model for exploring such constraints because they face warming temperatures on temperate breeding grounds and declining rainfall on many tropical non-breeding areas. Here, we use longitudinal data on spring departure dates of American redstarts ( Setophaga ruticilla ) to show that annual variation in tropical rainfall and food resources are associated with marked change in the timing of spring departure of the same individuals among years. This finding challenges the idea that photoperiod alone regulates the onset of migration, providing evidence that intensifying drought in the tropical winter could hinder adaptive responses to climatic warming in the temperate zone.


2015 ◽  
Vol 28 ◽  
pp. 9-17
Author(s):  
Dinesh Ghimire ◽  
Tej Bahadur Thapa

Effective conservation of Sloth bear requires detailed information regarding their distribution and habitat use. This study attempted to generate baseline data on distribution and habitat preference of Sloth Bear in Chitwan National Park, Nepal during March–May 2012. The study area was divided into 74 grids each measuring 16 Km2. Of the total grids, 35 were randomly selected for occupancy sampling. A total of 288 spatial replicates were sampled in 35 different grids recording 87 direct or indirect evidences of Sloth bear. Among them, 50 diggings, 25 scats, four scrapes with live animals in eight points were detected in four different habitat types of the Park. The variance to mean ratio showed clumped distribution of Sloth bear. The RPI values revealed that the mixed forest was found to be most preferred (RPI = 0.42) by Sloth Bear followed by grassland (RPI = 0.21). Riverine forest and Sal forest were less preferred (RPI = -0.25 and -0.11 respectively) but not avoided. Distribution of Sloth bear was influenced by distance to nearest water sources, distance to road and altitude. Similarly, disturbances like human activities, presence of cattle and fi re were found to affect the distribution of Sloth bear.J. Nat. Hist. Mus. Vol. 28, 2014: 9-17


The Condor ◽  
2001 ◽  
Vol 103 (1) ◽  
pp. 38-44 ◽  
Author(s):  
Katia Lombardini ◽  
Robert E. Bennetts ◽  
Christophe Tourenq

Abstract We examined habitat use by Little Egrets (Egretta garzetta) and Cattle Egrets (Bubulcus ibis) that nest together in mixed-species colonies in the Camargue of southern France. We explored the relative use of seven habitat types in relation to their availability and tested the hypothesis that selection of habitat types was related to foraging success, with the prediction that increased foraging success in a given habitat corresponded with increased use of that habitat type. Ricefields and other agricultural habitats were used more than expected by Cattle Egrets, an invasive species in southern Europe; whereas Little Egrets, which are native to the Camargue, tended to select natural freshwater marshes and lagoons. Results were consistent with the hypothesis that increasing use of habitats corresponded with higher foraging success for both species. However, when this analysis was restricted to habitats with sufficient numbers of birds to enable estimates of biomass intake, the association was no longer apparent for Little Egrets.


2005 ◽  
Vol 32 (7) ◽  
pp. 587 ◽  
Author(s):  
Robyn Molsher ◽  
Chris Dickman ◽  
Alan Newsome ◽  
Warren Müller

Twenty-one feral cats were radio-tracked using direct sighting and triangulation techniques (amassing 730 location fixes) during winter in an agricultural landscape in central-western New South Wales. Factors affecting home-range size, home-range overlap and habitat use were assessed. Mean home-range size was 248 ha (s.e. = 34.9, n = 15 cats, 598 location fixes). Home-range size and habitat use were not influenced by sex or age of adult cats, prey abundance or time of day. However, cat weight significantly influenced range size, with heavier cats having larger ranges than smaller cats. Although the cats are apparently solitary, their home ranges overlapped considerably, particularly between young adults and old adult cats. Cats were active both by day and night and did not occupy permanent dens. Home ranges encompassed mixed habitat types that provided both shelter and prey. Open woodland and open forest were the main habitat types covered by home ranges, but within these areas cats showed a preference for grassland, where rabbits were more abundant. The results recorded in this study indicate that cat-control programs should concentrate in mixed habitat areas, where both shelter and food are available, and over widely dispersed areas. The absence of group living suggests that the effectiveness of virally vectored fertility or biological control agents would be limited.


2013 ◽  
Vol 23 (4) ◽  
pp. 487-494 ◽  
Author(s):  
UGO MELLONE ◽  
PASCUAL LÓPEZ-LÓPEZ ◽  
RUBÉN LIMIÑANA ◽  
VICENTE URIOS

SummaryRecent advances in bird tracking technologies are revealing that migratory birds use temporal staging sites other than breeding and wintering areas, and these areas deserve conservation efforts. Eleonora’s Falcon Falco eleonorae is a long-distance migratory raptor that breeds colonially on islands and is considered a priority species for conservation. Anecdotal observations indicate that during the pre-breeding period, Eleonora’s Falcons stay in inland areas far away from the colonies, but, to date there are no detailed data concerning the connectivity between these areas and breeding colonies. Using satellite telemetry, we analysed data from four summering events belonging to three individuals breeding in two colonies in the Western Mediterranean (Spain). All of them made inland movements in areas up to c.400 km distant from the respective breeding colonies, visiting several habitats, from forests to arable lands, probably taking advantage of high densities of insects. Perturbations occurring in these areas could threaten Eleonora’s Falcons with serious consequences at the population level. We suggest that conservation measures implemented at breeding and wintering grounds may not suffice and that temporary staging areas should be identified at a larger scale and deserve protection as well.


Sign in / Sign up

Export Citation Format

Share Document