Population assessment and habitat associations of the Visayan Hornbill (Penelopides panini) in Northwest Panay, Philippines

Abstract Background Seven out of ten hornbill species in the Philippines are threatened with extinction. Among these is the endangered Visayan Hornbill (Penelopides panini), found on the islands of Panay and Negros. Threatened by habitat loss and hunting, its population size is thought to have declined from 1800 individuals 20 years ago to less than 1000. However, a recent study on Negros estimated 3564 individuals across three core forest blocks. This study aims to quantify the Visayan Hornbill population size in and around the Northwest Panay Peninsula Natural Park (NWPPNP) on Panay, the largest contiguous low-elevation forest landscape remaining across its range, and its broad habitat associations across a gradient of environmental degradation. Methods Hornbills were surveyed using 10-min distance sampling point counts (n = 367) along transects (average length 1.1 km). Environmental variables were recorded along transects, while habitat was classified into primary forest, secondary forest, plantation, or open habitat. Distance software was used to estimate population densities stratified by habitat, with the overall population estimate taken as a mean of habitat density estimates weighted by habitat area. Using generalized linear mixed models, hornbill occurrence was modelled using combinations of nine environmental variables as main and two-way fixed effects. Results Surveys covered 204.4 km2 of the 374.8 km2 Northwest Panay Peninsula. Hornbills were not recorded in plantations or open habitats. Hornbill density was significantly higher in primary forest (17.8 individuals/km2 ± 26.9% CV) than in secondary forest (3.7 individuals/km2 ± 33.2% CV; z = 15.212, P < 0.001). The overall population estimate for the NWPPNP and environs is 2109 individuals, and 2673 individuals for the entire Northwest Panay Peninsula. Hornbill presence was best explained by a model including distance from the Park boundary alongside five interaction effects and transect as a random effect. Distance, and the interaction between distance and medium-sized trees were significant predictors of hornbill presence. Conclusions Our study evidences the habitat preference of the Visayan Hornbill, highlights the importance of the NWPPNP for the species’ conservation, and provides strong evidence for re-assessing the global population size.

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Abundance and habitat associations of parrots at a hillforest site in Papua New Guinea

Pacific Conservation Biology ◽

10.1071/pc060015 ◽

2006 ◽

Vol 12 (1) ◽

pp. 15 ◽

Cited By ~ 6

Author(s):

Stuart J. Marsden ◽

Craig T. Symes

Keyword(s):

Papua New Guinea ◽

Secondary Forest ◽

New Guinea ◽

Abundant Species ◽

Habitat Associations ◽

Primary Forest ◽

Lower Altitude ◽

Management Area ◽

Total Lack ◽

Parrot Species

Despite New Guinea's importance for parrot species, there is an almost total lack of quantitative data on abundances or habitat associations of parrots on the island. We present such data for 15 parrot species within the species-rich (21 species) Crater Mountain Wildlife Management Area, Papua New Guinea. The four most abundant parrot species made up 70% of all parrots recorded in primary forest and 76% in old gardens. Several species had estimated densities of 10?60 birds per km2 and we suggest that the most abundant species on New Guinea are at least as common as those on the surrounding islands. Two species of particular conservation importance, Palm Cockatoo Probosciger aterrimus and Pesquefs Parrot Psittrichas fulgidus had estimated densities of just one bird per km2, while several other notably rare species included Dusky Lory Pseudeos fuscata and the fig-parrots Cyclopsitta diopthalma and Psittaculirostris desmarestii. Most parrot species were strongly associated with the lower and flatter areas of the site, where mature secondary forest dominated. Again, this is a pattern shared with parrots on nearby islands, and the finding emphasizes the importance of protecting lower-altitude mature forests within the region.

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Inventarisasi Jenis Pohon Pada Cagar Alam Gunung Ambang, Sulawesi Utara

Jurnal MIPA ◽

10.35799/jm.4.2.2015.8528 ◽

2015 ◽

Vol 4 (2) ◽

pp. 115

Author(s):

Akbar Arafah Embo ◽

Roni Koneri ◽

Saroyo . ◽

Adelfia Papu

Keyword(s):

Life Support ◽

Secondary Forest ◽

Primary Forest ◽

Line Transect ◽

Sampling Point ◽

Secondary Forests ◽

North Sulawesi ◽

The People ◽

Family Types

Pohon sebagai penyusun utama kawasan hutan berperan penting dalam pengaturan tata air, cadangan plasma nutfah, penyangga kehidupan, sumber daya pembangunan dan sumber devisa Negara. Peranan pohon-pohon dalam komunitas hutan semakin sulit dipertahankan mengingat tekanan masyarakat terhadap kelompok tumbuhan dari waktu ke waktu terus meningkat.Penelitian ini bertujuan untuk mengkaji jenis-jenis pohon yang berada di kawasan Cagar Alam Gunung Ambang, Sulawesi Utara. Metode penelitian yang digunakan yaitu metode garis berpetak yang merupakan modifiksi dari metode petak atau plot ganda dan metode jalur. Tipe habitat yang dijadikan titik pengambilan sampel adalah hutan primer dan hutan sekunder. Hasil pengamatan diperoleh sebanyak 38 jenis pohon penyusun hutan di Gunung Ambang yang termasuk dalam 22 suku. Pada hutan primer disusun oleh 37 jenis dan 22 suku, sedangkan pada hutan sekunder terdiri dari 28 jenis yang termasuk dalam 18 suku. Jenis pohon yang mendominasi setiap lokasi penelitian yaitu suku Magnoliaceae dan Arecaceae.Tree as the main constituent of forests play an important role in water regulation, germplasm reserves, life support, development resources and the country's foreign exchange resources. The role of trees in the forest communities are difficult to be sustained because the people pressure increase on the trees day by day. This study aims to assess the types of trees that are in the nature reserve area of Gunung Ambang, North Sulawesi. The method used is the line transect plots that is modified from the plot method or a double plot and track method. The type of habitat that is used as the starting sampling point is the primary forests and secondary forests. Result of observations showed that Gunung Ambang is composed by 38 species of plant in 22 family. In the primary forest composed by 37 species and 22 Family, whereas in secondary forest consists of 28 species in 18 family. Types of trees that dominate each research location are Family Magnoliaceae and Family Arecaceae.

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Population assessment and habitat associations of the Visayan Hornbill Penelopides panini in Northwest Panay, Philippines

10.1101/2021.08.31.458333 ◽

2021 ◽

Author(s):

Holly Isabelle Mynott ◽

David Charles Lee ◽

Rhea Aranas Santillan ◽

Christian J&uumlrgen Schwarz ◽

Benjamin Tacud ◽

...

Keyword(s):

Population Size ◽

Habitat Loss ◽

Environmental Degradation ◽

The Philippines ◽

Habitat Associations ◽

Forest Landscape ◽

Population Assessment ◽

Natural Park

Seven out of 10 hornbill species in the Philippines are threatened with extinction. Among these is the Endangered Visayan hornbill Penelopides panini, found on Panay and Negros islands. Threatened by habitat loss and hunting, its population size is thought to have declined from 1,800 individuals 20 years ago to less than 1,000. However, a recent study on Negros estimated 3,564 individuals across three core forest blocks. This study aims to quantify the Visayan hornbill population size in and around the Northwest Panay Peninsula Natural Park on Panay, the largest contiguous low-elevation forest landscape remaining across its range, and its broad habitat associations across a gradient of environmental degradation.

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Population sizes, status and habitat associations of the restricted-range bird species of Sumba, Indonesia

Bird Conservation International ◽

10.1017/s0959270900002938 ◽

1995 ◽

Vol 5 (1) ◽

pp. 21-52 ◽

Cited By ~ 29

Author(s):

Martin J. Jones ◽

Mark D. Linsley ◽

Stuart J. Marsden

Keyword(s):

Census Data ◽

Secondary Forest ◽

Function Analysis ◽

Bird Species ◽

Habitat Associations ◽

Primary Forest ◽

Restricted Range ◽

Point Counts ◽

Population Sizes ◽

Bird Census

SummaryThe island of Sumba was visited in 1989 and 1992 with the aim of collecting data on its avifauna. The endemic and other restricted-range bird species are very poorly known and, potentially, at great risk from extinction due to habitat change. Using standardized methods, habitat and bird census data were collected in eight forest areas. Analysis of the habitat data shows that most of the restricted-range species are forest-dependent. The exception is Turnix everetti (Sumba Buttonquail), which is found in open grassland. Discriminant Function Analysis was used to define habitat associations in a more precise and objective way. The species with the most specific requirements are Ptilinopus dohertyi (Red-naped Fruit-dove) and Zoothera dohertyi (Chestnut-backed Thrush), which are associated with primary forest at high altitudes, and Cacatua sulphurea (Sulphur-crested Cockatoo) and Rhyticeros everetti (Sumba Hornbill), which prefer evergreen primary or mature secondary forest at low altitudes. The results of the bird censuses were combined with data on habitat cover from satellite photographs to produce estimates of total population sizes. Among the rarest and most endangered species on Sumba are three which are represented by endemic subspecies: C. sulphurea (estimated population 3,200 birds), Eclectus roratus (Eclectus Parrot) (1,900), Tanygnathus megalorynchos (Great-billed Parrot) (1,700). The rarest endemic species is R. everetti, with a population of approximately 6,500. It is suggested that the census method used – point counts With distance estimates to bird contacts – is the best compromise for multi-species surveys in tropical forests.

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The Príncipe Thrush Turdus xanthorhynchus: a newly split, ‘Critically Endangered’, forest flagship species

Bird Conservation International ◽

10.1017/s0959270910000390 ◽

2010 ◽

Vol 20 (4) ◽

pp. 375-381 ◽

Cited By ~ 3

Author(s):

MARTIN DALLIMER ◽

MARTIM MELO ◽

NIGEL J. COLLAR ◽

PETER J. JONES

Keyword(s):

Population Size ◽

Confidence Intervals ◽

Secondary Forest ◽

Iucn Red List ◽

Critically Endangered ◽

Primary Forest ◽

Limited Area ◽

Land Uses ◽

Gulf Of Guinea ◽

Primary Forests

SummaryRecently recognised as specifically distinct, the Príncipe Thrush Turdus xanthorhynchus is endemic to the island of Príncipe in the Gulf of Guinea, West Africa. Formerly treated as conspecific with the more abundant T. olivaceofuscus from the nearby island of São Tomé, the Príncipe Thrush is considered rare and likely to be restricted to primary rainforest. A 2007 survey of Príncipe comprising 177 point transect locations covering 13 sites under different land uses (six in primary forest, three in secondary forest and four in plantations) encountered 18 individuals. Thrushes were found only in primary rainforest, where overall densities were 0.10 birds ha−1, equating to a population size of 435 individuals (95% confidence intervals: 208–913). We adjusted this estimate to take into account the fact that the highest density (0.22 birds ha−1) only occurred above 600 m, giving a final estimated population size of only 364 birds (95% confidence intervals: 186–887). In light of evidence of recent declines, possibly driven by hunting pressure, in the number of mature individuals and the limited area of occurrence of the species, the IUCN Red List category for the Príncipe Thrush should be ‘Critically Endangered’ under both criteria B1a+b(iii and v) and C2a(ii). The recent designation of the primary forests of southern Príncipe as a protected area (Parque Natural d’Obô do Príncipe) provides an opportunity for the conservation of this newly described species, which we recommend is used as a flagship for the forests as a whole.

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Spider diversity in the Bukit Timah Nature Reserve, Singapore

Gardens’ Bulletin Singapore ◽

10.26492/gbs71(suppl.1).2019-08 ◽

2019 ◽

Vol 71 ((suppl.1)) ◽

pp. 209-243

Author(s):

J.K.H. Koh ◽

D.J. Court

Keyword(s):

Nature Reserve ◽

New Records ◽

Secondary Forest ◽

Distinct Species ◽

Primary Forest ◽

Preliminary Results ◽

Vegetation Zones ◽

Comprehensive Survey ◽

Quantitative Analyses ◽

First Time

This paper discusses the preliminary results of the first comprehensive survey of the spiders of the Bukit Timah Nature Reserve (BTNR) in Singapore. Two plots were established in each of the three zones of vegetation, viz., primary forest, old secondary forest, and maturing secondary forest. They were repeatedly sampled over an 18-month period. Sorting of the collection so far suggests that the three vegetation zones harbour rather different spider assemblages. Only ~9% of the total spider fauna recovered was shared by all three zones. The results have also yielded a preliminary picture of dominance, abundance and rarity. Although first intended to obtain a baseline for future quantitative analyses, the survey became a testing ground to modify and refine methodology so as to conduct future quantitative surveys with greater scientific rigour. Taxonomic work on the samples so far shows that the spiders in the BTNR span over 43 families, of which six families are listed for the first time in Singapore. The tally is summarised in an interim checklist of BTNR spiders. The checklist, with a total of 317 entries, shows that there are 158 described species of spiders in BTNR, of which 25 species are new records for Singapore. Another 159 morphospecies are provisionally recognised as distinct species, some of which may be new to science. Our observations during the survey have allowed us to provide a narrative of BTNR spider diversity against a backdrop of their microhabitat specialisation.

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MANAJEMEN DATA SPASIAL: PENGGUNAAN TANAH WILAYAH PEDESAAN DI SUMATERA BARAT

Jurnal Spasial ◽

10.22202/js.v5i2.3090 ◽

2019 ◽

Vol 5 (2) ◽

pp. 48-53

Author(s):

Afrital Rezki, S.Pd., M.Si ◽

Erna Juita ◽

Dasrizal Dasrizal ◽

Arie Zella Putra Ulni

Keyword(s):

Land Use ◽

Paddy Field ◽

Secondary Forest ◽

Water Bodies ◽

Primary Forest ◽

Land Uses ◽

Forest Land ◽

Land Use Patterns ◽

Crop Fields ◽

Mixed Plantations

Perkembangan penggunaan tanah bergerak horisontal secara spasial ke arah wilayah yang mudah diusahakan. Penggunaan tanah juga bergerak secara vertikal dalam rangka menaikkan mutunya. Penelitian ini bertujuan untuk menganalisis pola penggunaan lahan, bagaimana manajemen penggunaan lahan di satu wilayah berdasarkan batas Nagari. Metode yang digunakan adalah analsisis spasial dengan interpretasi citra penginderaan jauh, survey lapangan, dan analisis deskriptif. Pertumbuhan pemukiman Nagari Sungai Sariak Kecamatan VII Koto Kabupaten Padang Pariaman mengakibatkan pemanfaatan ruang menjadi tumpang tindih. Diperlukan cara-cara pengelolaan dan managemen penggunaan tanah dalam rangka pembangunan berkelanjutan yang menaikkan taraf hidup masyarakat dan tidak menimbulkan kerugian lingkungan.Terdapat 9 jenis penggunaan lahan yang ada di Nagari Sungai Sariak. Penggunaan lahan tersebut adalah Primary Forest, Secondary Forest, Paddy Field, Settlement, Mixed Plantations, Crop Fields, Water Bodies, Bushes, dan Plantations. Penggunaan lahan yang paling luas di Nagari Sungai Sariak adalah jenis penggunaan lahan Primary Forest, sebesar 48% dari total luas wilayah Nagari Sungai Sariak. Pada tahun 2011 sampai tahun 2016, penggunaan lahan paling luas terjadi pada penggunaan lahan jenis Primary Forest yang kemudian menjadi Mixed Plantations. Land use Changes moved horizontally spatially towards areas that are easily cultivated. The land use also moves vertically in order to increase its quality. This study aims to analyze land use patterns, how land use management in one area is based on Nagari boundaries. The method used is spatial analysis with interpretation of remote sensing images, field surveys, and descriptive analysis. The growth of Nagari Sungai Sariak in Kecamatan VII Koto, Kabupaten Padang Pariaman resulted in overlapping use of space. Management methods are needed and management of land use in the framework of sustainable development that raises the standard of living of the community and does not cause environmental losses. There are 9 types of land use in the Nagari Sungai Sariak. The land uses are Primary Forest, Secondary Forest, Paddy Field, Settlement, Mixed Plantations, Crop Fields, Water Bodies, Bushes, and Plantations. The most extensive land use in Nagari Sungai Sariak is the type of Primary Forest land use, amounting to 48% of the total area of the Nagari Sungai Sariak. From 2011 to 2016, the most extensive land use occurred in Primary Forest land uses which later became Mixed Plantations.

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A random effects population dynamics model based on proportions-at-age and removal data for estimating total mortality

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f2012-103 ◽

2012 ◽

Vol 69 (11) ◽

pp. 1881-1893 ◽

Cited By ~ 6

Author(s):

Verena M. Trenkel ◽

Mark V. Bravington ◽

Pascal Lorance

Keyword(s):

Population Dynamics ◽

Random Effects ◽

Fixed Effects ◽

Random Effect ◽

Total Mortality ◽

Estimation Bias ◽

Effective Sample Size ◽

Dynamics Model ◽

Population Dynamics Model ◽

Study Parameter

Catch curves are widely used to estimate total mortality for exploited marine populations. The usual population dynamics model assumes constant recruitment across years and constant total mortality. We extend this to include annual recruitment and annual total mortality. Recruitment is treated as an uncorrelated random effect, while total mortality is modelled by a random walk. Data requirements are minimal as only proportions-at-age and total catches are needed. We obtain the effective sample size for aggregated proportion-at-age data based on fitting Dirichlet-multinomial distributions to the raw sampling data. Parameter estimation is carried out by approximate likelihood. We use simulations to study parameter estimability and estimation bias of four model versions, including models treating mortality as fixed effects and misspecified models. All model versions were, in general, estimable, though for certain parameter values or replicate runs they were not. Relative estimation bias of final year total mortalities and depletion rates were lower for the proposed random effects model compared with the fixed effects version for total mortality. The model is demonstrated for the case of blue ling (Molva dypterygia) to the west of the British Isles for the period 1988 to 2011.

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Responses of Bat Communities (Mammalia: Chiroptera) to Forest Loss and Habitat Conversion in Southern Cameroon

Tropical Conservation Science ◽

10.1177/19400829211010360 ◽

2021 ◽

Vol 14 ◽

pp. 194008292110103

Author(s):

Patrick Jules Atagana ◽

Eric Moïse Bakwo Fils ◽

Sevilor Kekeunou

Keyword(s):

Secondary Forest ◽

Biosphere Reserve ◽

Abundant Species ◽

Primary Forest ◽

Habitat Types ◽

Habitat Transformation ◽

Significant Difference ◽

Southern Cameroon ◽

Habitat Conversion ◽

Species Specific

We aimed to assess how bats are affected by habitat transformation by comparing bat assemblages in four habitat types: primary forest, secondary forest, cocoa plantations and human habitations in the Dja Biosphere Reserve of southern Cameroon. Bats were sampled in the four habitat types using mist nets. During 126 nights, a total of 413 bats were captured, belonging to four families, 16 genera and 24 species. Ninety three individuals (17 species) were captured in the primary forest, followed by plantations (105 individuals, 14 species), human habitations (159 individuals, 10 species), and secondary forest (55 individuals, eight species). Megaloglossus woermanni was recorded in all the four habitats, and was the most abundant species (105 individuals). The analysis of bat assemblage between habitat types showed a statistically significant difference in species composition. The distribution of the six most abundant species ( Epomops franqueti, Megaloglossus woermanni, Rousettus aegyptiacus, Dohyrina cyclops, Hipposideros cf. caffer and Hipposideros cf. ruber) was influenced by habitat types. Our results suggest that the decrease in species richness observed in disturbed habitats may be due to habitat perturbations of primary forest habitats. Therefore, it is important to examine the effects of habitat conversion at species level, as responses are often species-specific.

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Determining the Rate of Ergot-alkaloid Degradation in Toxic Endophyte-infected Tall Fescue Hay and Haylage During Long Term Storage

Journal of Animal Science ◽

10.1093/jas/skab096.038 ◽

2021 ◽

Vol 99 (Supplement_2) ◽

pp. 22-22

Author(s):

Charles A Zumbaugh ◽

Susannah A Gonia ◽

Kathryn M Payne ◽

Thomas B Wilson

Keyword(s):

Tall Fescue ◽

Ergot Alkaloid ◽

Fixed Effects ◽

High Performance ◽

Nutritive Value ◽

Day Treatment ◽

Random Effect ◽

Storage Period ◽

Neutral Detergent Fiber ◽

Experimental Unit

Abstract The objectives of this experiment were to determine changes in the nutritive value and ergot alkaloid concentrations of endophyte-infected tall fescue hay and haylage during a 180-d storage period. Forage from a single field of Kentucky-31 tall fescue was cut for hay in late June and allowed to dry in the field. The dry matter (DM) of the windrow of cut forage was measured every 2 h after clipping. Forage was sampled from the windrow in 6 location blocks once forage DM reached target levels for haylage and hay treatments. Haylage and hay samples were taken when the DM of the windrow reached 50% and 80%, respectively. Seven subsamples of each treatment within block were chopped to 1.91 cm in length with a lettuce chopper and vacuum sealed in oxygen-excluding bags. Sample bags were stored indoors and opened at 30 d intervals over the 180-d storage period. Samples were analyzed for pH, nutritive value, and individual ergot alkaloid concentrations using high-performance liquid chromatography. Within each storage day, treatment within block was considered the experimental unit. Data were analyzed in SAS using the MIXED procedure with fixed effects of treatment, day, and the treatment by day interaction. Location block was considered a random effect. As expected, pH was decreased for haylage compared to hay at all time points (P < 0.01) and DM was greater (P < 0.01) for hay compared to haylage. Neutral detergent fiber values were greater (P < 0.01) for hay compared to haylage and declined during storage (P < 0.01). Total ergot alkaloid concentrations did not differ by treatment (P = 0.61), but ergovaline concentrations declined (P < 0.01) during storage. Collectively, these results indicate minimal differences in nutritive value and ergot alkaloid concentrations between hay and haylage during storage, and that ergovaline concentrations decline during storage.

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