Wintering Behaviour and Spatial Ecology of Eurasian Wigeon Anas Penelope in a Coastal Mediterranean Wetland Complex (Guerbes-Sanhadja) of Northeastern Algeria

2017 ◽  
Vol 10 (2) ◽  
pp. 84-91 ◽  
Author(s):  
Laid Bouchaala ◽  
Ali Elafri ◽  
Nabil Charchar ◽  
Mohamed Boukhemza ◽  
Moussa Houhamdi
Keyword(s):  
Spatial Ecology ◽  
Wetland Management ◽  
Common Species ◽  
Sensitive Species ◽  
Bird Abundance ◽  
Wetland Complex ◽  
Anas Penelope ◽  
Migration Phenology ◽  
Northeastern Algeria

As rare and threatened species, ecological information about common waterbirds is needed to assess priorities for wetland management. In this study, we attempt to provide information about the spatial ecology and wintering behaviour of one of the most common species of the coastal Mediterranean wetland complex of northeastern Algeria, the Eurasian Wigeon Anas penelope. Over the three winters of the study the maximum number of recorded Eurasian Wigeon across all sites rose from 1,096 in 2010/11 to 1,397 in 2012/13. This represents a 27% increase over three years in the Guerbes-Sanhadja region. Among these wetland complex sites abundance varied markedly during the three wintering periods of study, being highest in Garaet Hadj-Tahar and Garaet Beni Mhamed (ranging from 300–700 individuals), and lowest in the remaining sites, which never exceeded 150 individuals. Bird abundance often peaked in January of each year and decreased as winter progressed. Wigeon have similar patterns of migration phenology among years at Garaet Hadj-Tahar and Garaet Beni Mhamed. At the remaining sites, they exhibited a different pattern. The multiple regression analysis for all seasons showed a marginally significant correlation between Wigeon abundance changes and three environmental variables of the wetland complex exclusively in the spring seasons (depth, vegetation and temporariness). A roosting area is identified as a functional role of the Guerbes-Sanhadja wetland complex for this anatid, since they spent all of the daytime sleeping, swimming (ranged from 30 to 40%), and resting (from 15 to 25%) in all winters. Despite their semi-permanent and unprotected status (apart from only three sites), these patched wetlands provide suitable conditions for this sensitive species, and therefore should receive the attention of wetland management.

scholarly journals Distribution of seed dormancy classes across a fire-prone continent: effects of rainfall seasonality and temperature

2020 ◽  
Author(s):  
Justin C Collette ◽  
Mark K J Ooi
Keyword(s):  
Seed Dormancy ◽  
Critical Role ◽  
Fire Regimes ◽  
Common Species ◽  
Functional Responses ◽  
Stochastic Disturbance ◽  
Climate Gradients ◽  
Selective Pressures ◽  
Rainfall Seasonality

Abstract Background and Aims Different seed dormancy classes control the timing of germination via different cues. The ecological dissimilarities between classes therefore suggest that they are likely to be subject to different selective pressures, and that species within each class will have diverse functional responses. We aimed to investigate this by assessing how variation in the distribution of dormancy classes is correlated with regional environmental factors, in particular rainfall seasonality and temperature. Additionally, we compare the relative proportions of species with physiological (PD) or physical (PY) dormancy to assess whether dormancy class influences their ability to persist under different rainfall seasonality regimes. Methods Dormancy class was assigned for 3990 species from 281 genera occurring across two climate regions, with either winter or aseasonal rainfall, across temperate fire-prone Australia. All regions have similar vegetation and fire regimes. Using a Bayesian framework, we compared the distribution of dormancy classes across temperature and rainfall climate gradients, for threatened and common species. Key Results A high dormant:non-dormant species ratio highlighted the critical role of dormancy across our study regions. Critically, species showing PD were more likely to be threatened in aseasonal rainfall climate regions. Conclusions Our results support the assumption that dormancy is favoured in environments with stochastic disturbance

scholarly journals Experimental evidence of spatial memory and home range affinity in White-tailed Deer (Odocoileus virginianus)

2015 ◽  
Vol 129 (1) ◽  
pp. 1 ◽  
Author(s):  
Michael E. Nelson
Keyword(s):  
Home Range ◽  
Spatial Memory ◽  
Experimental Evidence ◽  
Odocoileus Virginianus ◽  
Spatial Ecology ◽  
Home Ranges ◽  
Directional Movement ◽  
Before And After

The role of spatial memory in the movement of animals through landscapes remains elusive. To examine spatial memory and home range affinity of White-tailed Deer (Odocoileus virginianus) in northeastern Minnesota during 1995–2007, I translocated 17 adult does with known home ranges to unfamiliar sites and radio-tracked them after their release. Twelve does wearing transmitting radio-collars returned to their home ranges. Death and collar expiration precluded determination of whether the remaining five does would have returned to home ranges. Three of five does wearing global positioning system collars traveled throughout hundreds of square kilometres, circling, backtracking, and returning to release sites, while two others exhibited directional movement for tens of kilometres. Four does that survived to parturition stopped traveling and moved at hourly rates similar to those of control does during the first three weeks of the typical fawn-rearing period, but continued traveling later. Their aberrant extensive travel before and after interruption by parturition suggests that they recognized they were in unfamiliar areas, demonstrating both their capacity and propensity to search for and occupy the familiar space of their individual home ranges. Their successful return to home ranges provided experimental evidence of spatial memory and further elucidated its pervasive role in White-tailed Deer spatial ecology.

scholarly journals A Fixed-radius Point Count Method for Nonbreeding and Breeding Season Use

The Auk ◽  
1986 ◽  
Vol 103 (3) ◽  
pp. 593-602 ◽  
Author(s):  
Richard L. Hutto ◽  
Sandra M. Pletschet ◽  
Paul Hendricks
Keyword(s):  
Bird Species ◽  
Common Species ◽  
Bird Abundance ◽  
Point Count ◽  
Bird Density ◽  
Count Method ◽  
Species Abundances ◽  
Fixed Radius ◽  
Point Count Method ◽  
A Site

Abstract We provide a detailed description of a fixed-radius point count method that carries fewer assumptions than most of the currently popular methods of estimating bird density and that can be used during both the nonbreeding and breeding seasons. The method results in three indices of bird abundance, any of which can be used to test for differences in community composition among sites, or for differences in the abundance of a given bird species among sites. These indices are (1) the mean number of detections within 25 m of the observer, (2) the frequency of detections within 25 m of the observer, and (3) the frequency of detections regardless of distance from the observer. The overall ranking of species abundances from a site is similar among the three indices, but discrepancies occur with either rare species that are highly detectable at great distances or common species that are repulsed by, or inconspicuous when near, the observer. We argue that differences in the behavior among species will preclude an accurate ranking of species by abundance through use of this or any other counting method in current use.

scholarly journals Spatial Ecology of Small Mammals in North-central Chile: Role of Precipitation and Refuges

2007 ◽  
Vol 88 (6) ◽  
pp. 1532-1538 ◽  
Author(s):  
W. Bryan Milstead ◽  
Peter L. Meserve ◽  
Andrea Campanella ◽  
M. Andrea Previtali ◽  
Douglas A. Kelt ◽  
...  
Keyword(s):  
Small Mammals ◽  
Spatial Ecology ◽  
North Central ◽  
Central Chile

scholarly journals The revision of specimens of the Cladonia pyxidata-chlorophaea group (lichenized Ascomycota) from northeastern Poland deposited in the herbarium collections of University in Bialystok

2017 ◽  
Vol 51 (2) ◽  
Author(s):  
Anna Matwiejuk
Keyword(s):  
Great Part ◽  
Common Species ◽  
Chemical Variation ◽  
Secondary Chemistry ◽  
Ne Poland ◽  
Northeastern Poland ◽  
Herbarium Collections ◽  
Shed Light

In northeastern Poland, the chemical variation of the <em>Cladonia chlorophaea-pyxidata</em> group was much neglected, as TLC has not been used in delimitation of species differing in the chemistry. As a great part of herbal material of University in Bialystok from NE Poland was misidentified, I found my studies to be necessary. Based on the collection of 123 specimens deposited in Herbarium of University in Bialystok, nine species of the <em>C. pyxidata-chlorophaea</em> group are reported from NE Poland. The morphology, secondary chemistry, and ecology of examined lichens are presented and the list of localities is provided. The results revealed that <em>C. fimbriata</em> is the most common species in the northeastern Poland, comprising around 33% of the studied specimens. <em>Cladonia conista</em>, <em>C. cryptochlorophaea</em>, and <em>C. merochlorophaea</em> are known only from very few locations. This study shed light on the role of the lichens substances to diagnosis of the species of <em>C. pyxidata-chlorophaea</em> group.

scholarly journals The role of wetland management agencies within the local community in the conservation of wetlands in Uganda

2019 ◽  
Vol 7 (1) ◽  
pp. 59-74
Author(s):  
Alex Barakagira ◽  
Anton H. de Wit
Keyword(s):  
Natural Resources ◽  
Local Community ◽  
Wetland Management ◽  
Fish Farming ◽  
Wetland Degradation ◽  
Cross Sectional ◽  
Environment Management ◽  
Political Interference ◽  
National Environment

Abstract Wetlands in Uganda are believed to be socio-economically important for providing water for drinking, irrigation, fisheries, recreation, transport and agriculture among others. Bearing in mind the host of benefits wetlands provide to local communities, if they are harnessed without the mind, they could end up being over utilized and ultimately degraded and not continue to provide a stream of functions, attributes and services. This could be one of the primary reasons why special Departments and Institutions like the National Environment Management Authority and Wetlands Management Department were created to manage the country’s natural resources including wetlands. The study was initiated to explore how wetland management agencies influence members of the local community on matters concerning the conservation of wetlands in Uganda. A cross-sectional research design was used to collect qualitative and quantitative data. A questionnaire survey was conducted amongst four hundred households to collect information concerning the role of wetland management agencies among members of the local community for the conservation of wetlands in Uganda. More information was obtained from senior officials from the National Environment Management Authority, Wetland Management Department, and District Natural Resources Officers from the study area using a non-structured questionnaire. Key informant interviews and direct observations were also used to collect data. The study revealed that gathering materials for building and for making crafts, agricultural activities, unsustainable mining of clay and sand for building contributed to wetland degradation. Some circumstances like high population growth, unclear wetland ownership, unawareness of the indirect functions of wetlands also contributed to wetland degradation. It was found that the wetland management agencies have been ineffective towards the conservation of wetlands mainly due to inadequate funding, political interference, and lack of specific judges for wetland related court cases among others. For wetland management agencies to effectively perform their duties leading to the protection and conservation of wetlands in Uganda, the study recommends that members of the local community should be allowed to practice wetland edge farming, fish farming in ponds constructed in wetlands, and to leave some parts of these vital wetlands that have been reclaimed to regenerate, in addition to addressing the main reported hindrances that are stifling the smooth running of the activities of the agencies.

scholarly journals Understory bat roosts, availability and occupation patterns in a Neotropical rainforest of Costa Rica

2016 ◽  
Vol 64 (3) ◽  
Author(s):  
David Villalobos-Chaves ◽  
Jendry Vargas-Murillo ◽  
Emmanuel Rojas-Valerio ◽  
Brian W. Keeley ◽  
Bernal Rodríguez-Herrera
Keyword(s):  
Costa Rica ◽  
Selection Process ◽  
Common Species ◽  
Sensitive Species ◽  
Anthropogenic Pressures ◽  
Roosting Ecology ◽  
Neotropical Rainforest ◽  
Traveled Distances ◽  
Occupation Rate ◽  
Biological Reserve

The strong link between bats and their roosts is widely recognized as being particularly significant. Despite this, roosting ecology of bats is poorly understood and much of the basic information is still unknown. In this study, we investigated the availability and occupation patterns of four roost types (trees, caves, termite nests and tents) used by bats at Tirimbina Biological Reserve (TBR), Costa Rica. To accomplish our aim, we systematically surveyed both sides of established trails and transects, looking for understory roosts. Potential roosts were examined for bat presence in order to establish occupation. Roost availability and density were estimated using traveled distances (km) and inspected area (10 m for trees/caves and 15 m for tents/termite nests) of each trail or transect sampled. For the tent roosts, data on taxonomic information of plant modified, type of architecture, condition and construction achievement were also recorded. The area surveyed represented 45.4 % of the total area of the TBR (345 ha). Tents were the most common roost (56.6 % of all roosts, N = 223), followed by trees (24.4 %, N = 96), termite nests (18.8 %, N = 74) and caves (0.2 %, N = 1). We detected only 27 roosts occupied by bats (6.8 % of all roosts, 0.17 occupied roosts/ha). Caves showed the highest occupation rate (100 %, N = 1), followed by trees (17.7 %, N = 17), tents (3.6 %, N = 8) and termite nests (1.3 %, N = 1). We found the roosts for 10 species, representing 33.9 % of the bat fauna documented at the reserve (62 species). Density of roosts per bat species varied between 0.017-0.138 roosts/ha. Phyllostomidae was the best-represented family with Micronycteris microtis representing the most common species encountered. Four distinct tent architectures were documented. Bifid architecture was the most common (133 tents), followed by Conical (47 tents), Apical (27 tents) and Inverted Boat (16 tents). Most of the tents found were healthy (76.7 %, N = 171) and totally constructed (88.8 %, N = 198). Our study demonstrated that occupied bat roosts are difficult to find in the forest. When compared to the roost availability, the low occupation rates suggested that, at least in our study area, roosts might not be a limiting resource. Nevertheless, to confirm this hypothesis, information about fidelity and selection process of the species is fundamental for understanding to what extent these roosts meet the requirements to be inhabited or modified. Worldwide conservation efforts on bats should focus on understanding roosting ecology, especially due to anthropogenic pressures that are continuously reducing the availability of roosts, which undoubtedly contributes to the risk of extinction for specialized and sensitive species.

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