scholarly journals Habitat characteristics assessmen of the wetlands with breeding Ferruginous Duck Aythya nyroca and Pochard A. ferina in Bulgaria / Ocena habitatnih značilnosti mokrišč z gnezdečimi kostanjevkami Aythya nyroca in sivkami A. ferina v Bolgariji

Acrocephalus ◽  
2012 ◽  
Vol 32 (150-151) ◽  
pp. 127-134 ◽  
Author(s):  
Nikolai Petkov
Keyword(s):  
Conservation Status ◽  
Habitat Preferences ◽  
Open Water ◽  
Breeding Habitat ◽  
Habitat Characteristics ◽  
Artificial Wetlands ◽  
Breeding Range ◽  
Preferred Habitat ◽  
Floating Vegetation ◽  
Mosaic Vegetation

Abstract The Ferruginous Duck Aythya nyroca and Pochard A. ferina are both regular breeders in Bulgaria. In the 19th and early 20th centuries, the Ferruginous Duck was a widely distributed and abundant breeding species in Bulgaria, while Pochard was first confirmed to breed in the country only in the 1950s. Breeding habitat characteristics of Ferruginous Duck and Pochard were assessed in 2002 during a national census of the former species in 30 and 23 wetlands, respectively, where the species were present. Preferred habitat characteristics were determined based on vegetation cover, water depth, and the presence of mosaic vegetation, bank side vegetation, floating vegetation, shallow or steep banks, shallow mudflats, shallow vegetated areas and woodland along the banks. In 2002, the Ferruginous Duck population in Bulgaria was restricted more to artificial wetlands, like fishponds and micro-reservoirs, while Pochard preferred more natural wetlands, predominantly natural marshes. The altitude of wetlands with Ferruginous Ducks varied markedly, with breeding recorded up to 880 m a.s.l., while Pochard bred at lower altitudes, mostly below 300 m a.s.l. Analysis revealed that Ferruginous Ducks preferred well-vegetated, comparatively shallow wetlands with well-structured mosaic vegetation and a diversity of microhabitats, like shallow mudflats and floating vegetation. The Pochard was found to be more of a generalist in wetland selection, significantly correlated with fewer wetland parameters, and showed preference only for larger, open-water bodies. These results could help explain and give some insight into the reasons for the differences in range size, numbers and distribution of the two species and their respective conservation status in Europe and worldwide. The Pochard, whilst close to the limits of the breeding range in Bulgaria, expands its range in Europe, occupying a variety of wetlands and thus having a favourable status. The Ferruginous Duck is more of a habitat specialist, which limits its distribution and makes it more susceptible to habitat changes. These habitat preferences and the deterioration of the wetland habitats in many parts of its range could probably explain the Ferruginous Duck decreasing population and shrinking breeding range, and thus its current unfavourable conservation status.

scholarly journals Abundance and Habitat Preferences of Gray Vireos (Vireo Vicinior) on the Colorado Plateau

The Auk ◽  
2006 ◽  
Vol 123 (1) ◽  
pp. 33-44
Author(s):  
Scott Schlossberg
Keyword(s):  
Additional Data ◽  
Colorado Plateau ◽  
Conservation Status ◽  
Habitat Preferences ◽  
Breeding Habitat ◽  
Short Term ◽  
Northern Arizona ◽  
Pinyon Pine ◽  
Primary Habitat

Abstract The Gray Vireo (Vireo vicinior; hereafter “vireo”) is a little-studied songbird with small breeding and wintering ranges. Because of uncertainty about vireo populations, conservationists are concerned about the future of this species. The goal of the present study was to provide new data on the ecology of the vireo to help determine its conservation status. During May and June 2001, I studied breeding habitat selection by vireos on the Colorado Plateau in northern Arizona and southern Utah. I surveyed for vireos and collected vegetation data on 31 transects in pinyon-juniper (Pinus edulis-Juniperus spp.) woodlands throughout this region. Estimated density of vireos was 0.064 ± 0.011 (mean ± SE) birds ha−1. Analysis at two scales showed that the vireo’s primary habitat preference was for areas where junipers predominate over pinyon pine. Vireos also preferred areas with some shrub cover, and they increased with the prevalence of sagebrush (Artemisia tridentata) among shrubs. Additionally, vireos were more common at lower elevations, an effect that was largely independent of vegetation characters. Habitats preferred by vireos are widespread in the southwestern United States and may be increasing in extent as woodlands expand into grasslands and shrublands. On the basis of these results, I suggest that vireo populations are relatively safe, at least for the short term. Additional data on vireo demography are needed to ensure the long-term conservation of this species. Abundancia y Preferencias de Hábitat de Vireo vicinior en la Planicie de Colorado

Breeding habitat preference and nest success of Red-necked Phalaropes on Niglintgak Island, Northwest Territories

2008 ◽  
Vol 86 (12) ◽  
pp. 1346-1357 ◽  
Author(s):  
Bree Walpole ◽  
Erica Nol ◽  
Vicky Johnston
Keyword(s):  
Habitat Preference ◽  
Nest Site ◽  
Multiple Scales ◽  
Open Water ◽  
Nest Site Selection ◽  
Habitat Model ◽  
Breeding Habitat ◽  
Habitat Characteristics ◽  
Using Data ◽  
Summer Storm

Red-necked Phalaropes ( Phalaropus lobatus (L., 1758)) breed throughout arctic and subarctic wetlands. These wetlands provide Red-necked Phalaropes dense graminoid habitat that shelters and conceals nests, and freshwater ponds where phalaropes engage in social interactions and feed on small aquatic invertebrates. We studied breeding habitat preference of Red-necked Phalaropes at multiple scales and determined which, if any, nest-site characteristics influenced hatching success. Red-necked Phalaropes avoided habitat at the meso (home range) scale containing large areas of mud and shrub cover, and selected sites with greater cover of graminoids, aquatic emergents, and open water than that available in the environment. At the micro (nest) scale, phalaropes chose sites dominated by graminoids and water. In 2005, concealed nests experienced higher daily nest survival than exposed nests. In 2006, 40% of nests were destroyed during a summer storm surge and we detected no differences in habitat characteristics between the remaining successful and unsuccessful nests. We suggest that annual differences in the adaptive value of nest-site selection depend on the relative abundance of mammalian and avian predators. A habitat model using data at the meso scale correctly identified phalarope habitat and has the potential to be used broadly across the western Arctic.

Dietary composition of endangered seahorses determined by stable isotope analysis

2017 ◽  
Vol 68 (5) ◽  
pp. 831 ◽  
Author(s):  
S. Valladares ◽  
D. X. Soto ◽  
M. Planas
Keyword(s):  
Stable Isotope ◽  
Environmental Changes ◽  
Conservation Status ◽  
Management Strategies ◽  
Isotope Analysis ◽  
Primary Source ◽  
Habitat Characteristics ◽  
Conservation Actions ◽  
Isotope Mixing Models ◽  
North Western

The lack of integrated measures for assessing the feeding ecology of seahorses may restrict the effectiveness of conservation actions on wild populations of worldwide threatened seahorse species. Identifying dietary sources will allow researchers to determine their degree of vulnerability to environmental changes, redefine their conservation status and apply appropriate management strategies. The resource use of the seahorse Hippocampus guttulatus inhabiting coastal waters of Galicia (north-western Iberian Peninsula) was assessed for three populations and 2 years using stable isotope mixing models. The Bayesian mixing model (MixSIAR) estimated the relative contributions of the dietary sources to the seahorse diet and revealed that Caprellidea were the primary source, followed by Gammaridea and Caridea. Mysidae and Annelida represented the less dominant prey. This prey preference can be explained by the foraging behaviour of seahorses. Different contributions of Gammaridea and Caridea to the diet were found among sites, indicating different habitat characteristics and hence different habitat use by seahorses within each site. In addition, differences were encountered among sexes. Caprellidea was the dominant prey for females, whereas Gammaridea was the dominant prey for males. The findings of the present study will contribute to the knowledge of feeding patterns of H. guttulatus, providing relevant data for conservation of this endangered species.

scholarly journals Habitat selection of Himalayan Musk Deer Moschus leucogaster (Mammalia: Artiodactyla: Moschidae) with respect to biophysical attributes in Annapurna Conservation Area of Nepal

2021 ◽  
Vol 13 (7) ◽  
pp. 18703-18712
Author(s):  
Bijaya Neupane ◽  
Nar Bahadur Chhetri ◽  
Bijaya Dhami
Keyword(s):  
Endangered Species ◽  
Management Strategies ◽  
Mixed Forest ◽  
Habitat Characteristics ◽  
Musk Deer ◽  
Importance Value Index ◽  
Importance Value ◽  
Conservation Area ◽  
Preferred Habitat ◽  
Annapurna Conservation Area

Himalayan or White-bellied Musk Deer Moschus leucogaster, an IUCN indexed endangered species, is distributed in isolated pockets in the Himalaya. The deer population is decreasing owing to several pressures that include habitat loss and fragmentation, and poaching. It is essential to identify preferred habitat characteristics to support appropriate management strategies for conserving this endangered species. This study was carried out in the Nysheang basin of Annapurna Conservation Area of Nepal to identify habitats preferred by the musk deer. Habitat field parameters were collected using transect surveys. To analyze vegetation use and availability, nested quadrate plots size 20 m2 were established. Ivlev’s electivity index (IV) (-1 to +1) was employed to determine habitat preference, and one-way ANOVA (F) and chi-square tests (χ2) were used to examine different habitat parameters. Similarly, the importance value index (IVI) of the vegetation was calculated. Our results showed that the Himalayan Musk Deer strongly preferred habitats at 3601–3800 m altitude (IV= 0.3, F= 4.58, P <0.05), with 21–30º slope (IV= 0.2, F= 4.14, P <0.05), 26–50 % crown cover (IV= 0.25, F= 4.45, P <0.05), 26–50 % ground cover (IV= 0.15, F= 4.13, P <0.05), and mixed forest (IV= 0.29, χ2= 28.82, df= 3, p <0.001). Among the trees, Abies spectabilis (IVI= 74.87, IV= 0.035) and Rhododendron arboretum (IVI= 55.41, IV= 0.02) were the most preferred, while Rhododendron lepidotum, Cassiope fastigiata (IV= 0.35) and Berberis aristata (IV= 0.25) were the most preferred shrubs, and Primula denticulata (IV= 0.87) and Primula rotundifolia (IV= 0.31) were the most preferred herbs. These preferred habitat conditions should be maintained and conserved to sustain a viable population of deer in the study area. Further studies will be required to assess the effects of climate change on habitat suitability. 

scholarly journals Keanekaragaman Pari Hasil Tangkapan Nelayan di TPI Karangantu Banten

2021 ◽  
Vol 9 (3) ◽  
pp. 257-266
Author(s):  
Erreull Isyhadu Putri ◽  
◽  
Dinda Rizqi ◽  
Fenia Alya ◽  
Tia Azizah
Keyword(s):  
Species Diversity ◽  
Literature Review ◽  
Diversity Index ◽  
Conservation Status ◽  
Habitat Characteristics ◽  
Species Diversity Index ◽  
Interview Method

This study aims to determine the diversity of rays caught by fishermen in TPI Karangantu Banten. This research uses interview method and literature review. The discussion of the observations includes classification, habitat, characteristics, and conservation status. The results of this study indicate that there is a diversity of rays, namely the results of the families obtained from the observations are Rhinopteridae, Dasyatidae, and Gymnuridae). From the results of the calculation of the species diversity index using the Shannon Wiener formula, it is included in the medium category. This diversity can be used as knowledge and inventory for biodiversity, especially the chondrichthyes class in TPI Karangantu, Serang, Banten.

A new species of frog in the Litoria ewingii species group (Anura: Pelodryadidae) from south-eastern Australia

Zootaxa ◽  
2020 ◽  
Vol 4858 (2) ◽  
pp. 201-230
Author(s):  
MICHAEL MAHONY ◽  
BEDE MOSES ◽  
STEPHEN V. MAHONY ◽  
FRANK L. LEMCKERT ◽  
STEPHEN DONNELLAN
Keyword(s):  
New Species ◽  
Conservation Status ◽  
Habitat Preferences ◽  
Nuclear Genome ◽  
Species Group ◽  
Nucleotide Polymorphisms ◽  
Population Declines ◽  
Genetic Groups ◽  
Eastern Australia ◽  
A New Species

Population declines and range contractions among Australian frogs that commenced in the early 1980s continue in some species that were once widespread. The generality of this pattern has been difficult to discern, especially for those species that are encountered rarely because they have restricted periods of calling activity with poorly defined habitat preferences, and are not common. Several lines of evidence indicate that Litoria littlejohni is such a species. This frog was once known from mid-eastern New South Wales to eastern Victoria, and evidence from wildlife atlas databases and targeted searches indicate that it has declined in large portions of its former range, leaving several populations that are isolated, in some cases restricted in distribution, and of small size. We investigated the relationships among populations using mitochondrial ND4 nucleotide sequences and single nucleotide polymorphisms (SNPs) from the nuclear genome. We found that northern and southern populations form two highly divergent genetic groups whose distributions abut at the southern margin of the Sydney Basin Bioregion and these genetic groups also show divergence in morphology and male advertisement calls. Here we describe the populations to the south of the Sydney Basin Bioregion as a new species and provide information on its distribution and ecology. In light of the apparent isolation and small size of known populations of the new species and the consequent restriction of the range of L. littlejohni, we assessed the conservation status of both species. 

scholarly journals Do Some Northern Goshawk Nest Areas Consistently Fledge More Young Than Others?

The Condor ◽  
2002 ◽  
Vol 104 (2) ◽  
pp. 343-352
Author(s):  
Erica L. McClaren ◽  
Patricia L. Kennedy ◽  
Sarah R. Dewey
Keyword(s):  
British Columbia ◽  
New Mexico ◽  
Spatial Patterns ◽  
Vancouver Island ◽  
Breeding Habitat ◽  
Habitat Characteristics ◽  
Accipiter Gentilis ◽  
Uinta Mountains ◽  
Northern Goshawk ◽  
Jemez Mountains

Abstract In long-lived raptors, research suggests that some nest areas consistently fledge more young than others, with the majority of young in the population being produced by a few females. If this claim were true for Northern Goshawk (Accipiter gentilis) populations, it would benefit land managers to identify high-quality goshawk breeding habitat. We examined whether the number of young fledged varied spatially among Northern Goshawk nest areas within three study areas where long-term reproductive data from goshawks were available: (1) Vancouver Island, British Columbia; (2) Jemez Mountains, New Mexico; and (3) Uinta Mountains, Utah. A mixed-model ANOVA indicated there was minimal spatial variation in nest productivity among nest areas within the three study locations. Rather, nest areas exhibited high temporal variability in nest productivity within each study area. These results suggest that temporal patterns such as local weather and fluctuating prey populations influenced Northern Goshawk reproduction more than spatial patterns such as habitat characteristics. Nest productivity may inadequately reflect spatial patterns in goshawk reproduction and so it would be premature to assume that habitat quality for Northern Goshawks was equal among nest areas within these study areas. Future research should examine spatial variability among nest areas in adult and juvenile survival rates to gain a complete picture of population responses to habitat change. ¿Se Producen Consistentemente Más Volantones de Accipiter gentilis en Algunos Sitios de Anidación que en Otros? Resumen. Investigaciones en aves rapaces longevas sugieren que consistentemente más polluelos empluman en algunos sitios de anidación que en otros y que la mayoría de los juveniles en la población son producidos por unas pocas hembras. Si esto fuera cierto para poblaciones de Accipiter gentilis, ayudaría a las autoridades ambientales a identificar hábitat reproductivo de alta calidad para la especie. Evaluamos si el número de polluelos emplumados varió espacialmente entre sitios de anidación de A. gentilis dentro de tres áreas de estudio para las cuales había datos reproductivos de largo plazo disponibles: (1) Vancouver Island, British Columbia; (2) Jemez Mountains, New Mexico; y (3) Uinta Mountains, Utah. Un modelo mixto de análisis de varianza indicó que la variación espacial en la productividad de los nidos entre sitios de anidación dentro de las tres áreas de estudio fue mínima. En cambio, los sitios de anidación presentaron una alta variabilidad temporal en la productividad de los nidos dentro de cada área de estudio. Estos resultados sugieren que los patrones temporales como el clima y las fluctuaciones de las poblaciones de presas influencian la reproducción de A. gentilis más que los patrones espaciales como las características del hábitat. La productividad de los nidos puede reflejar inadecuadamente los patrones espaciales de la reproducción de A. gentilis, de modo que sería prematuro suponer que la calidad de hábitat fue igual entre los sitios de anidación dentro de las áreas de estudio. Para tener una perspectiva completa de la respuesta de las poblaciones a cambios en el ambiente, investigaciones futuras deberían examinar la variabilidad espacial entre sitios de anidación en las tasas de supervivencia de aves adultas y juveniles.

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