Distribution and habitat description of Junín Rail Laterallus tuerosi, Andean Peru

2017 ◽  
Vol 27 (3) ◽  
pp. 388-397 ◽  
Author(s):  
LARS DINESEN ◽  
ALAN CHAMORRO ◽  
JON FJELDSÅ ◽  
CONSTANTINO AUCCA
Keyword(s):  
Vegetation Structure ◽  
Water Levels ◽  
Suitable Habitat ◽  
Hydroelectric Power ◽  
Habitat Types ◽  
Open Spaces ◽  
Marsh Vegetation ◽  
Point Count ◽  
Point Counts ◽  
Juncus Balticus

SummaryDistribution and habitat description of the endangered Junín Rail Laterallus tuerosi were assessed during a field study between 6 and 20 February 2014 in the marshes surrounding Lake Junín in the high Andes of Peru, which is the only known locality for the species. By using point counts and playback, we found the species to be present in the marshland all around the lake, with preference for two clearly defined habitat types: one comprising extensively grazed tussocks of Festuca dolichophylla and the other of rather uniform stands of Juncus balticus with undergrowth, or smaller open spaces, with various low herbs. We estimate the suitable habitat of the species to be a minimum of 100 km2 and based upon our point count data we provide indicative population figures of 6,200 individuals, which is higher than previous estimates. No records were obtained without playback, although five minutes of silent listening prior to playback were used at each point. All records were in vegetation of at least 0.5 m tall and in the marshy edge on muddy ground with less than 20 cm of water depth. Grazing especially by sheep or cattle is a serious threat to the marsh vegetation structure essential for Junín Rail and the rail is also under pressure from fluctuations in water levels accentuated by regulation for hydroelectric power.

scholarly journals Study of the Milky Stork Bird (Mycteria cinerea) Population in Rawa Pacing, Kibang Pacing Village, Menggala Timur Sub-District, Menggala Timur Regency, Lampung Province

2018 ◽  
Vol 6 (2) ◽  
pp. 1
Author(s):  
Faizal Mahdi Syamal ◽  
Sugeng Prayitno Harianto
Keyword(s):  
Data Collection ◽  
Vegetation Structure ◽  
Natural Habitat ◽  
Bird Species ◽  
Distribution Patterns ◽  
Daily Activities ◽  
Point Count ◽  
Illegal Hunting ◽  
Point Counts ◽  
Point Count Method

Kibang Pacing Village with an area of 83.55 km2 had converted that lead to a change of the vegetation structure from multistrata into monostrata that could threaten the wildlife such as the milky stork bird (Mycteria cinerea) that classified as a threatened species. The objectives of this study were to determine the number of individual and distribution patterns of milky stork in Rawa Pacing at Kibang Pacing Village, Menggala Timur Sub-District, Tulang Bawang Regency. Data collection was conducted through direct observation using point count method at 3 (three) point counts. The results observed 513 encounters of the milky stork, showing the most encounter at Point Count 3. The higher encounter occurred in the morning than in the afternoon which because diurnal bird species generally started their daily activities to find foods in the morning. The abundance of milky stork population in Kibang Pacing Village was 126 individuals, showing the highest number at Point Count 3. Illegal hunting and other human activities in Rawa Pacing could potentially cause disruption on natural habitat that may threaten the existence and sustainability of the milky stork bird.  Keywords: milky stork, Mycteria cinerea, pacing swamp, population.

scholarly journals On the use of 10-minute point counts and 10-species lists for surveying birds in lowland Atlantic Forests in southeastern Brazil

2012 ◽  
Vol 52 (28) ◽  
pp. 333-340 ◽  
Author(s):  
Vagner Cavarzere ◽  
Thiago Vernaschi Vieira da Costa ◽  
Luís Fábio Silveira
Keyword(s):  
Rapid Assessment ◽  
Southeastern Brazil ◽  
Point Counting ◽  
Point Count ◽  
Point Counts ◽  
Time Period ◽  
Minute Point ◽  
Species Lists ◽  
Point Count Method ◽  
Breeding Seasons

Due to rapid and continuous deforestation, recent bird surveys in the Atlantic Forest are following rapid assessment programs to accumulate significant amounts of data during short periods of time. During this study, two surveying methods were used to evaluate which technique rapidly accumulated most species (> 90% of the estimated empirical value) at lowland Atlantic Forests in the state of São Paulo, southeastern Brazil. Birds were counted during the 2008-2010 breeding seasons using 10-minute point counts and 10-species lists. Overall, point counting detected as many species as lists (79 vs. 83, respectively), and 88 points (14.7 h) detected 90% of the estimated species richness. Forty-one lists were insufficient to detect 90% of all species. However, lists accumulated species faster in a shorter time period, probably due to the nature of the point count method in which species detected while moving between points are not considered. Rapid assessment programs in these forests will rapidly detect more species using 10-species lists. Both methods shared 63% of all forest species, but this may be due to spatial and temporal mismatch between samplings of each method.

scholarly journals Effect of Climate and Habitat on Morphological Characteristics and Fruit Production of Picralima Nitida (Stapf) in West Africa

2021 ◽  
Author(s):  
Ghislain Comlan AKABASSI ◽  
Elie Antoine Padonou ◽  
Achille Ephrem Assogbadjo ◽  
Noël Zirihi Guede
Keyword(s):  
Pearson Correlation ◽  
Habitat Type ◽  
Morphological Characteristics ◽  
Botanical Garden ◽  
Fruit Production ◽  
Natural Forest ◽  
Home Gardens ◽  
Suitable Habitat ◽  
Habitat Types ◽  
Pharmaceutical Industries

Abstract Picralima nitida is an important African medicinal plant species used in pharmaceutical industries and traditional medicine to treat several diseases. Despite its importance, the species faces conservation problem. This study evaluated the effect of climate and habitat on morphological characteristics and fruit production of P. nitida. A total of 132 fruiting trees was randomly sampled from three habitat types (home gardens, botanical garden and natural forest) and three soils (Nitisols, Arenosols and Acrisols) in Dahomey Gap and Guineo-Congolese zone. A total of 5 morphological traits and fruit production were recorded per tree to describe the relationship between morphological determinism of the species and climate. Pearson correlation was performed to identify the suitable habitat type in each climatic zone. Harmonized World Soil Database was used to determine physicochemical characteristics of the soil types on which the species occurred. Results revealed that the climatic zones (p < 0.001) and habitat types (p < 0.0001) influenced significantly the morphological characteristics and fruit production of P. nitida. High trees with more number of fruits were observed in home gardens on acid soils (Nitisols (pH: 5) and Arenosols (pH: 5.3)) in Dahomey Gap. In Guineo-Congolese zone, the species was more present in natural forest on acid Acrisols (pH: 5).

scholarly journals Dispersal across habitat boundaries: uncovering the demographic fates of populations in unsuitable habitat

2021 ◽  
Author(s):  
Megan C. Szojka ◽  
Rachel M. Germain
Keyword(s):  
Temporal Variability ◽  
Adult Life ◽  
Adult Plant ◽  
Suitable Habitat ◽  
Life Stages ◽  
Habitat Types ◽  
The Matrix ◽  
Probabilistic Process ◽  
Habitat Boundaries ◽  
Matrix Patch

AbstractPatchy landscapes are characterized by abrupt transitions among distinct habitat types, forcing species to cross habitat boundaries in order to spread. Since seed dispersal is a probabilistic process, with a kernel that decays with distance, most individuals will fail to reach new, suitable habitat. Although failed dispersers are presumed dead in population models, their demographic fates may not be so simple. If transient survival is possible within unsuitable habitat, then through time, individuals may be able to reach distant, suitable habitat, forming new populations and buffering species from extinction. In a fragmented Californian grassland, we explored the fates of individuals that crossed habitat boundaries, and if those fates differed among specialists dispersing from two habitat types: serpentine habitat patches and the invaded non-serpentine matrix. We surveyed the diversity of seedbank and adult life stages along transects that crossed boundaries between patches and the matrix. First, we considered how patch specialists might transiently survive in the matrix via seed dormancy or stepping-stone populations. Second, we investigated the dispersal of an invasive matrix specialist (Avena fatua) into patches, to assess if sink populations existed across the habitat boundary. We found that dormancy maintained populations of patch specialists deep into the matrix, as abundances of seedbanks and of adult plant communities differed with distance into the matrix. We found evidence that these dormant seeds disperse secondarily with vectors of material flows in the landscape, suggesting that they could eventually reach suitable patches even if they first land in the matrix. We found that A. fatua were largely absent deep in patches, where reproductive outputs plummeted and there was no evidence of a dormant seedbank. Our results not only reveal the demographic fates of individuals that land in unsuitable habitat, but that their ecological consequences differ depending on the direction by which the boundary is crossed (patch → matrix ≠ matrix → patch). Dormancy is often understood as a mechanism for persisting in face of temporal variability, but it may serve as a means of traversing unsuitable habitat in patchy systems, warranting its consideration in estimates of habitat connectivity.

scholarly journals The effects of grazing and mowing on large marsh grasshopper, Stethophyma grossum (Orthoptera: Acrididae), populations in Western Europe: a review

2018 ◽  
Vol 27 (1) ◽  
pp. 91-96 ◽  
Author(s):  
Jacqui Miller ◽  
Tim Gardiner
Keyword(s):  
Vegetation Structure ◽  
Western Europe ◽  
Conservation Management ◽  
Life Stages ◽  
Negative Effects ◽  
Habitat Types ◽  
The Uk ◽  
Grassland Habitats ◽  
Intensity Grazing ◽  
Refuge Areas

The large marsh grasshopper, Stethophymagrossum L. (Orthoptera: Acrididae), has undergone a significant range contraction in the UK and is now restricted to the bogs and mires of the New Forest and Dorset Heaths. In other parts of Western Europe, the species makes use of a wider range of wetland habitat types. Traditionally, many of these habitats would be managed through low intensity grazing, mowing, or both, and these measures are now often employed in the conservation management of wet grassland habitats. This paper reviews the effects of mowing and grazing on S.grossum populations, through looking at the potential impacts (both positive and negative) on different life stages of the grasshopper. Both techniques are valuable in the maintenance of an open and varied vegetation structure which is known to benefit S.grossum in all its life stages. However, grazing on very wet sites or at high intensity can result in trampling of vegetation and S.grossum eggs, and mowing which is too frequent may negatively affect populations through repeated losses of nymphs. Recommendations are given regarding the suitability of mowing and grazing for different habitats and intensity of management to generate the required vegetation structure. Measures are also outlined, such as the provision of unmown or ungrazed refuge areas, which can help reduce negative effects.

Problems with Avian Point Counts for Estimating Density of Northern Bobwhite—A Case Study

2011 ◽  
Vol 2 (1) ◽  
pp. 117-121 ◽  
Author(s):  
Roger D. Applegate ◽  
Robert E. Kissell ◽  
E. Daniel Moss ◽  
Edward L. Warr ◽  
Michael L. Kennedy
Keyword(s):  
Count Data ◽  
Distance Sampling ◽  
Bird Species ◽  
Northern Bobwhite ◽  
Model Fit ◽  
Point Count ◽  
Point Counts ◽  
Occupancy Estimation ◽  
Detection Probabilities

Abstract Point count data are used increasingly to provide density estimates of bird species. A favored approach to analyze point count data uses distance sampling theory where model selection and model fit are important considerations. We used uniform and half normal models and assessed model fit using χ2 analysis. We were unsuccessful in fitting models to 635 northern bobwhite Colinus virginianus observations from 85 avian point locations spanning 6 y (P ≤ 0.05). Most observations (74%) occurred in the outermost (&gt;100-m) distance radius. Our results violated the assumptions that all observations at the point are detected. The assumption that birds were assigned to the correct distance interval also was probably violated. We caution managers in implementing avian point counts with distance sampling when estimating northern bobwhite population density. We recommend exploring other approaches such as occupancy-estimation and modeling for estimating detection probabilities.

scholarly journals Singing in the suburbs: point count surveys efficiently reveal habitat associations for nocturnal Orthoptera across an urban-to-rural gradient

2020 ◽  
Vol 24 (6) ◽  
pp. 1031-1043
Author(s):  
Darin J. McNeil ◽  
Christina M. Grozinger
Keyword(s):  
Site Occupancy ◽  
Habitat Associations ◽  
Survey Method ◽  
Population Declines ◽  
Detection Rates ◽  
Point Count ◽  
Point Counts ◽  
Focal Species ◽  
Habitat Gradient ◽  
Count Surveys

Abstract As evidence for global insect population declines continues to amass, several studies have indicated that Orthoptera (grasshoppers, crickets, and katydids) are among the most threatened insect groups. Understanding Orthoptera populations across large spatial extents requires efficient survey protocols, however, many previously established methods are expensive and/or labor-intensive. One survey method widely employed in wildlife biology, the aural point count, may work well for crickets and katydids (suborder: Ensifera) because males produce conspicuous, species-specific mating calls. We conducted repeated point count surveys across an urban-to-rural gradient in central Pennsylvania. Occupancy analyses of ten focal species indicated that, although detection probability rates varied by species from 0.43 to 0.98, detection rates compounded over five visits such that all focal species achieved cumulative > 0.90. Factors associated with site occupancy varied among species with some positively associated with urbanization (e.g., Greater Anglewing, Microcentrum rhombifolium), some negatively associated with urbanization (e.g., Sword-bearing Conehead, Neoconocephalus ensiger), and others exhibiting constant occupancy across a habitat gradient (e.g., Common True Katydid, Pterophylla camellifolia). Our community-level analysis revealed that different species’ habitat associations interacted such that intermediate levels of urbanization (i.e., suburbs) hosted the highest number of species. Implications for insect conservation Ultimately, our analyses clearly support the concept that aural point counts paired with static occupancy modeling can serve as an important tool for monitoring night-singing Orthoptera populations. Applications of point count surveys by both researchers and citizen scientists may improve our understanding Ensifera populations and help in the global conservation of these threatened insects.

scholarly journals Movements of the Eastern Ribbonsnake (Thamnophis sauritus) in Nova Scotia

2016 ◽  
Vol 129 (4) ◽  
pp. 379
Author(s):  
T. L. Imlay ◽  
J. Saroli ◽  
T. B. Herman ◽  
S. W. Mockford
Keyword(s):  
Nova Scotia ◽  
Annual Variation ◽  
Prey Availability ◽  
Home Range Size ◽  
Water Levels ◽  
Suitable Habitat ◽  
Home Ranges ◽  
Daily Movement ◽  
The Status ◽  
Best Fit

The disjunct Eastern Ribbonsnake (Thamnophis sauritus) population in southwest Nova Scotia is listed as “threatened” by the committee on the Status of Endangered Wildlife in Canada. A study of the movements of the species at two lakeshore locations known to support a high density of Eastern Ribbonsnakes was undertaken in 2007 and 2008. Average seasonal movements at both sites ranged from 17 m to 84 m for juvenile snakes and 21 m to 130 m for adults; one neonate was recaptured during the study after travelling 32 m. The maximum distance travelled by an individual snake was 391 m in one season. The best-fit model to explain differences in daily movement patterns included year (P = 0.041), indicating that there is annual variation in the movements of this species. Low recapture rates precluded accurate estimates of home-range size, which varied roughly from 0.16 ha to 0.78 ha. Both movements and home ranges were larger than previously documented in Nova Scotia, but maximum distances travelled were consistent with a previous study in Michigan. Most documented movements were along the lakeshore within contiguous, suitable habitat. More work is needed to understand the frequency of large movements and triggers that initiate movements, e.g., changes in water levels, habitat suitability, or prey availability.

scholarly journals Variations in the abundance of three Parulidae species in the southern portion of the Brazilian Atlantic Forest, state of Paraná

2012 ◽  
Vol 84 (3) ◽  
pp. 721-726
Author(s):  
Cássius R. Santana ◽  
Gabriela M. Bochio ◽  
Luiz dos Anjos
Keyword(s):  
Atlantic Forest ◽  
Vegetation Structure ◽  
Rain Forest ◽  
Deciduous Forest ◽  
Brazilian Atlantic Forest ◽  
Forest Types ◽  
Point Counts ◽  
Significant Difference ◽  
Forest Strata ◽  
The Difference

We evaluated the distribution of abundance of three species of warblers in the southern portion of the Brazilian Atlantic Forest (BAF): Tropical Parula (Parula pitiayumi), the Golden-Crowned Warbler (Basileuterus culicivorus) and the White-Rimmed Warbler (Basileuterus leucoblepharus). Three types of forests comprise this region of the Atlantic Forest: seasonal semi-deciduous forest (SF), mixed rain forest (MF) and dense rain forest (DF). These forest types occur at different elevations: SF ranging from 200 to 800 m, MF ranging from 800 to 1,200 m and DF ranging from sea level up to 2,000 m. We used point counts in fifteen study areas distributed in the three forest types. The White-Rimmed Warbler and the Tropical Parula had higher abundances in MF, and their abundance was positively correlated with the elevation. The Golden-Crowned Warbler did not present a significant difference in abundance among the forest types, and no correlation between abundance and elevation was found. We suggest that the difference in the occupancy of the forest strata by the Golden-Crowned Warbler is because this species is more generalist and thus less sensitive to variations in the vegetation structure among the forests types when compared to the other two warbler species.

scholarly journals Does habitat structure influence capture probabilities? A study of reptiles in a eucalypt forest

2009 ◽  
Vol 36 (6) ◽  
pp. 509 ◽  
Author(s):  
Michael D. Craig ◽  
Andrew H. Grigg ◽  
Mark J. Garkaklis ◽  
Richard J. Hobbs ◽  
Carl D. Grant ◽  
...  
Keyword(s):  
Relative Abundance ◽  
Vegetation Structure ◽  
Habitat Structure ◽  
Pitfall Traps ◽  
Total Removal ◽  
Habitat Types ◽  
Jarrah Forest ◽  
Future Studies ◽  
Eucalypt Forest ◽  
Structural Variables

Pitfall traps are commonly used to examine differences in reptile communities among habitat types and disturbance regimes that differ in structure. However, capture rates and probabilities may be influenced by habitat structure, which invalidates comparisons of relative abundance among habitat types. To assess whether pitfall traps provide accurate reflections of density and whether habitat structure affects capture probabilities, we trapped at six sites in various jarrah-forest habitat types in south-western Australia, then intensively searched 150-m2 total-removal plots around each pitfall grid to obtain absolute densities of reptiles. Pitfall captures were significantly correlated with numbers on total-removal plots for Hemiergis initialis and Lerista distinguenda, indicating that pitfall traps provided accurate reflections of density for these species. Capture probabilities of H. initialis and L. distinguenda and all reptiles combined showed no significant correlations with any structural variables, indicating that capture probabilities were consistent across sites. We conclude that trapping provided accurate estimates of relative abundance for some species and that capture probabilities were not influenced by vegetation structure. Because many studies use trapping to estimate abundances among habitat types, we encourage researchers to investigate how vegetation structure influences capture probabilities, so that general patterns can be determined; we also suggest improvements for any future studies.

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