scholarly journals Macro-habitat preferences by the African manatee and crocodiles – ecological and conservation implications

Web Ecology ◽  
2012 ◽  
Vol 12 (1) ◽  
pp. 39-48 ◽  
Author(s):  
L. Luiselli ◽  
G. C. Akani ◽  
N. Ebere ◽  
F. M. Angelici ◽  
G. Amori ◽  
...  
Keyword(s):  
Habitat Selection ◽  
Coastal Lagoons ◽  
Habitat Preferences ◽  
Habitat Type ◽  
Null Model ◽  
Niche Overlap ◽  
West African ◽  
Conservation Implications ◽  
Type Selection ◽  
Selection Of

Abstract. African manatees (Trichechus senegalensis) and crocodiles are threatened species in parts of their range. In West Africa, crocodiles may constitute the main predators for manatees apart from humans. Here, we explore the macro-habitat selection of manatees and two species of crocodiles (West African crocodiles Crocodylus suchus and dwarf crocodile Osteolaemus tetraspis) in the Niger Delta (Nigeria), testing the hypotheses that (i) manatees may avoid crocodiles in order to minimize risks of predation, and (ii) the two crocodile species do compete. The study was carried out between 1994 and 2010 with a suite of different field techniques. We observed that the main macro-habitat types were freshwater rivers and coastal lagoons for manatees, mangroves for West African crocodiles, and rivers and creeks for dwarf crocodiles, with (i) the three species differing significantly in terms of their macro-habitat type selection, and (ii) significant seasonal influence on habitat selection of each species. Null models for niche overlap showed a significantly lower overlap in macro-habitat type use between manatee and crocodiles, whereas the two crocodiles were relatively similar. Null model analyses did not indicate any competitive interactions between crocodiles. On the other hand, manatees avoided macro-habitats where crocodiles, and especially West African crocodiles, are abundant.

Conservation of a rare arboreal mammal: habitat preferences of the Lumholtz's tree-kangaroo, Dendrolagus lumholtzi

2011 ◽  
Vol 33 (1) ◽  
pp. 5 ◽  
Author(s):  
Sigrid R. Heise-Pavlov ◽  
Sara L. Jackrel ◽  
Spenser Meeks
Keyword(s):  
Habitat Selection ◽  
Function Analysis ◽  
Habitat Preferences ◽  
Structural Features ◽  
Main Trunk ◽  
Faecal Pellets ◽  
Eastern Australia ◽  
North Eastern ◽  
Dendrolagus Lumholtzi ◽  
Selection Of

Success of conservation efforts of large and cryptic mammals is often limited due to a lack of knowledge of their habitat preferences. This study investigates factors that affect the habitat selection of the rare Lumholtz’s tree-kangaroo, Dendrolagus lumholtzi, using signs of its activity. The presence and absence of scratch marks on tree trunks and faecal pellets within a 100-cm radius around them were surveyed on 23 ha within a 65-ha large fragment of rainforest on the Atherton Tablelands, north-eastern Australia in order to classify trees as ‘actively used’ or ‘inactive’. Structural features of the 315 surveyed tree trunks were also recorded. Using discriminant function analysis, ‘actively used’ trees were found to have no epiphytes on the main trunk, less obstruction by neighbouring trees, shrubs or lianas within a 0.5-m radius of the trunk (particularly in the eastern direction), and a smaller diameter at breast height than ‘inactive’ trees. Smaller tree trunks and less obstruction may facilitate a more rapid movement into the canopy as well as provide potential escape routes from predators. More specific knowledge on factors that affect habitat selection of the Lumholtz’ tree-kangaroo will help in a reclassification of the threatened status of this species and assist in more effective conservation efforts.

scholarly journals Conservation implications of past and present nesting habitat selection of the endangered OspreyPandion haliaetuspopulation of the Canary Islands

Ibis ◽  
2013 ◽  
Vol 155 (4) ◽  
pp. 891-897 ◽  
Author(s):  
Beneharo Rodríguez ◽  
Airam Rodríguez ◽  
Manuel Siverio ◽  
Felipe Siverio
Keyword(s):  
Habitat Selection ◽  
Canary Islands ◽  
Nesting Habitat ◽  
Conservation Implications ◽  
Selection Of

Habitat use by female western roe deer (Capreolus capreolus): influence of resource availability on habitat selection in two contrasting years

2010 ◽  
Vol 88 (11) ◽  
pp. 1052-1062 ◽  
Author(s):  
M. Pellerin ◽  
C. Calenge ◽  
S. Saïd ◽  
J.- M. Gaillard ◽  
H. Fritz ◽  
...  
Keyword(s):  
Habitat Selection ◽  
Habitat Use ◽  
Resource Availability ◽  
Roe Deer ◽  
Habitat Type ◽  
Capreolus Capreolus ◽  
Home Ranges ◽  
Distribution Of Resources ◽  
The Relationship ◽  
Selection Of

In most previous studies of habitat selection, the use of a given habitat type is assumed to be directly proportional to its availability. However, the use and (or) the selection of a given habitat may be conditional on the availability of that habitat. We aim here to (i) identify the environmental variables involved in habitat selection, (ii) identify classes of individuals with similar patterns of habitat selection, and (iii) assess whether habitat use changes with changing availability of habitat types, within monthly home ranges of female western roe deer ( Capreolus capreolus (L., 1758)). We found that some females adjust their habitat use according to the distribution of resources within habitats. Females with similar home ranges in terms of resource quantity and quality showed similar patterns of habitat selection. Differences in habitat use between 2 years with contrasting resource availability showed that temporal changes of environmental conditions influenced the pattern of habitat selection by female roe deer. Habitat selection also differed between periods of the life cycle likely because of contrasted energy requirements. This study shows that the relationship between habitat use by herbivores and habitat availability is nonproportional, and that the availability of resources influences use mostly at intermediate values.

scholarly journals The Role of Subnivean Access in Winter Habitat Selection of Marten in Yellowstone National Park

1989 ◽  
Vol 13 ◽  
pp. 215-216
Author(s):  
Stuart Sherburne ◽  
John Bissonette
Keyword(s):  
Factor Analysis ◽  
Habitat Selection ◽  
National Park ◽  
Spatial Dynamics ◽  
Habitat Type ◽  
Winter Habitat ◽  
Proximate Factor ◽  
Selection Of ◽  
Habitat Variables

This research project has two primary goals. The first is to determine home range spatial dynamics of marten (Maxes americana) in Yellowstone relative to habitat type. Results of this analysis will aid in the understanding of marten habitat selection. The study's second goal is aimed at identifying the habitat variables that influence subnivean access. A proximate factor analysis of subnivean access behavior will be conducted to determine the components that make old growth suitable for marten. Results from both objectives will allow assessment of the effects of the 1988 fires in Yellowstone on marten habitat.

Habitat selection in the Pampa de Achala toad, Bufo achalensis

2007 ◽  
Vol 28 (1) ◽  
pp. 129-138 ◽  
Author(s):  
Gabriela Jofré ◽  
Christopher Reading ◽  
Ismael di Tada
Keyword(s):  
Habitat Selection ◽  
Habitat Preferences ◽  
Habitat Type ◽  
Breeding Site ◽  
Breeding Sites ◽  
Larval Survivorship ◽  
Stream Bank ◽  
Granite Outcrops ◽  
Tussock Grassland ◽  
Management Plans

AbstractHabitat selection in adult and juvenile Bufo achalensis was studied at La Ciénaga Stream, Pampa de Achala, Central Argentina from December 1998 to October 2001. Habitat preference was evaluated by comparing the observed use of each habitat type with its availability. Juveniles were surveyed on 32 occasions between January 1999 and March 2001 using 13 permanent transects. The effect of cattle on larval survivorship was also evaluated. Most adult and juvenile B. achalensis occurred within 300 m of each side of the breeding site stream. No correlation was found between body size and distances moved. Juveniles and adults selected granite outcrops after the breeding season and avoided the heavily grazed areas. Adults also selected the stream and used tall tussock grassland in proportion to its availability. Juveniles used loose, flat, relatively small stones as shelters whilst adults used larger rocks. The presence of cattle at the breeding sites directly reduced larval survivorship by trampling, and indirectly through sediment deposition at the breeding sites resulting from increased stream bank erosion. The habitat preferences of B. achalensis suggest that long term cattle grazing also affects them adversely through deterioration of their transition habitat from tall tussock grassland to short sward. Future conservation management plans for B. achalensis must include the protection of the breeding sites and the surrounding terrestrial area if they are to be effective.

scholarly journals Status, conservation and habitat selection of the Houbara Bustard Chlamydotis undulata fuertaventurae on Lanzarote (Canary Islands)

1996 ◽  
Vol 6 (3) ◽  
pp. 229-239 ◽  
Author(s):  
Aurelio Martín ◽  
Manuel Nogales ◽  
Miguel A. Hernández ◽  
Juan Antonio Lorenzo ◽  
Félix M. Medina ◽  
...  
Keyword(s):  
Habitat Selection ◽  
Canary Islands ◽  
Total Population ◽  
Habitat Preferences ◽  
Total Count ◽  
Small Island ◽  
Houbara Bustard ◽  
Selection Of

SummaryA Houbara survey of Lanzarote and the small island of Graciosa, during December 1993, resulted in a total count of 146 birds and an estimated total population of about 400 Houbaras. These numbers are higher than found on most previous surveys of Fuerteventura, considered as the main stronghold of this subspecies, and indicate that the Houbara population on Lanzarote is much more important than was formerly supposed. A study of habitat preferences showed that the species tended to select zones with greater height of shrubs.

scholarly journals Behaviour-specific habitat selection patterns of breeding barn owls

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Robin Séchaud ◽  
Kim Schalcher ◽  
Ana Paula Machado ◽  
Bettina Almasi ◽  
Carolina Massa ◽  
...  
Keyword(s):  
Habitat Selection ◽  
Habitat Use ◽  
Habitat Preferences ◽  
Habitat Type ◽  
Agricultural Practices ◽  
Barn Owl ◽  
Path Selection ◽  
Tyto Alba ◽  
Beneficial Effects ◽  
Barn Owls

Abstract Background The intensification of agricultural practices over the twentieth century led to a cascade of detrimental effects on ecosystems. In Europe, agri-environment schemes (AES) have since been adopted to counter the decrease in farmland biodiversity, with the promotion of extensive habitats such as wildflower strips and extensive meadows. Despite having beneficial effects documented for multiple taxa, their profitability for top farmland predators, like raptors, is still debated. Such species with high movement capabilities have large home ranges with fluctuation in habitat use depending on specific needs. Methods Using GPS devices, we recorded positions for 134 barn owls (Tyto alba) breeding in Swiss farmland and distinguished three main behavioural modes with the Expectation-Maximization binary Clustering (EMbC) method: perching, hunting and commuting. We described barn owl habitat use at different levels during the breeding season by combining step and path selection functions. In particular, we examined the association between behavioural modes and habitat type, with special consideration for AES habitat structures. Results Despite a preference for the most common habitats at the home range level, behaviour-specific analyses revealed more specific habitat use depending on the behavioural mode. During the day, owls roosted almost exclusively in buildings, while pastures, meadows and forest edges were preferred as nocturnal perching sites. For hunting, barn owls preferentially used AES habitat structures though without neglecting more intensively exploited areas. For commuting, open habitats were preferred over wooded areas. Conclusions The behaviour-specific approach used here provides a comprehensive breakdown of barn owl habitat selection during the reproductive season and highlights its importance to understand complex animal habitat preferences. Our results highlight the importance of AES in restoring and maintaining functional trophic chains in farmland.

scholarly journals Habitat selection of the Common Quail (Coturnix coturnix) in an intensively managed agricultural environment

2019 ◽  
Vol 27 (1) ◽  
pp. 99-109
Author(s):  
Tamás Márton Németh ◽  
Petra Kelemen ◽  
Ágnes Csiszár ◽  
Gyula Kovács ◽  
Sándor Faragó ◽  
...  
Keyword(s):  
Habitat Selection ◽  
Breeding Season ◽  
Habitat Preferences ◽  
Agricultural Environment ◽  
North West ◽  
Coturnix Coturnix ◽  
The Common ◽  
Intensively Managed ◽  
Common Quail ◽  
Selection Of

Abstract This study investigated the habitat selection of the Common Quail (Coturnix coturnix) during the breeding season of 2014 in an intensively managed agricultural environment (LAJTA Project, North-West Hungary). In order to assess the habitat preferences of the Common Quail, habitat composition around occupied plots were compared with unoccupied control plots. To characterize the habitat, a total of 11 variables related to vegetation structure and diversity, food availability and landscape were quantified. Multivariate methods (PCA and GLMs) were used to distinguish the main factors influencing habitat selection and to model the presence of the Common Quail. Based on our results, in the LAJTA Project, high probability of Common Quail presence can be predicted in plots with higher herbaceous cover and more abundant arthropod communities. The network of ecotone habitats, particularly the proximity to woody habitats, also appeared to have significant importance during the breeding season.

scholarly journals Non-random seasonal variation in the structure of a Mediterranean snake community

Web Ecology ◽  
2007 ◽  
Vol 7 (1) ◽  
pp. 40-46
Author(s):  
E. Filippi ◽  
L. Luiselli
Keyword(s):  
Monte Carlo ◽  
Community Structure ◽  
Seasonal Variation ◽  
Central Italy ◽  
Habitat Type ◽  
Null Model ◽  
Niche Overlap ◽  
Null Models ◽  
Habitat Niche ◽  
Mediterranean Community

Abstract. The community structure in relation to habitat type was studied in a Mediterranean community of snakes from Canale Monterano, central Italy. Habitat data for snakes were analysed both overall and divided by season, i.e. spring (April–June) and summer (July–September). Community analyses were performed using null models (RA2 and RA3 algorithms) and Monte Carlo simulations on habitat niche overlap estimates. Null models suggested that the community was assembled non-randomly (according to RA2 but not RA3), indicating that the generalist-specialist nature (the number of resource states, but not necessarily the types) used by each species in the assemblage reduced ecological similarity. Similar results were reached also performing the same null model procedures on the spring datasets, whereas no structure emerged during summer either by RA2 or RA3 algorithms. In general, this study suggests that the community structure of snakes during spring may be shaped by the different eco-physiological needs of the various species (probably, the differential tolerance to cold and the consequent needs of finding suitable hibernacula), whereas the lack of structure during summer may be caused by the between-species similar foraging needs.

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