Assessing conservation status of resident and migrant birds on Hispaniola with mist-netting

We analyzed temporal trends in mist-net capture rates of resident (n= 8) and overwintering Nearctic-Neotropical migrant (n= 3) bird species at two sites in montane broadleaf forest of the Sierra de Bahoruco, Dominican Republic, with the goal of providing quantitative information on population trends that could inform conservation assessments. We conducted sampling at least once annually during the winter months of January–March from 1997 to 2010. We found evidence of declines in capture rates for three resident species, including one species endemic to Hispaniola. Capture rate of Rufous-throated Solitaire (Myadestes genibarbis) declined by 3.9% per year (95% CL = 0%, 7.3%), Green-tailed Ground-Tanager (Microligea palustris) by 6.8% (95% CL = 3.9%, 8.8%), and Greater Antillean Bullfinch (Loxigilla violacea) by 4.9% (95% CL = 0.9%, 9.2%). Two rare and threatened endemics, Hispaniolan Highland-Tanager (Xenoligea montana) and Western Chat-Tanager (Calyptophilus tertius), showed statistically significant declines, but we have low confidence in these findings because trends were driven by exceptionally high capture rates in 1997 and varied between sites. Analyses that excluded data from 1997 revealed no trend in capture rate over the course of the study. We found no evidence of temporal trends in capture rates for any other residents or Nearctic-Neotropical migrants. We do not know the causes of the observed declines, nor can we conclude that these declines are not a purely local phenomenon. However, our findings, along with other recent reports of declines in these same species, suggest that a closer examination of their conservation status is warranted. Given the difficulty in obtaining spatially extensive, long-term estimates of population change for Hispaniolan birds, we suggest focusing on other metrics of vulnerability that are more easily quantified yet remain poorly described, such as extent of occurrence.

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Assessing conservation status of resident and migrant birds on Hispaniola with constant-effort mist-netting

10.7287/peerj.preprints.1368v1 ◽

2015 ◽

Author(s):

John D Lloyd ◽

Chris C Rimmer ◽

Kent P McFarland

Keyword(s):

Population Change ◽

Conservation Status ◽

Capture Rate ◽

Temporal Trends ◽

Bird Species ◽

Quantitative Information ◽

Neotropical Migrant ◽

Migrant Birds ◽

Conservation Assessments ◽

Capture Rates

We analyzed temporal trends in mist-net capture rates of resident (n = 8) and overwintering Nearctic-Neotropical migrant (n = 3) bird species at two sites in montane broadleaf forest of the Sierra de Bahoruco, Dominican Republic, with the goal of providing quantitative information on population trends that could inform conservation assessments. We conducted sampling at least once annually during the winter months of January – March from 1997 – 2010. We found evidence of steep declines in capture rates for three resident species, including one species endemic to Hispaniola. Capture rate of Rufous-throated Solitaire (Myadestes genibarbis) declined by 3.9% per year (95% CL = 0%, 7.3%), Green-tailed Ground-Tanager (Microlegia palustris) by 6.8% (95% CL = 3.9%, 8.8%), and Greater Antillean Bullfinch (Loxigilla violacea) by 4.9% (95% CL = 0.9%, 9.2%). Two rare and threatened endemics, Hispaniolan Highland-Tanager (Xenolegia montana) and Western Chat-Tanager (Calyptophilus tertius), showed statistically significant declines, but we have low confidence in these findings because trends were driven by exceptionally high capture rates in 1997 and varied between sites. Analyses that excluded data from 1997 revealed no trend in capture rate over the course of the study. We found no evidence of temporal trends in capture rates for any other residents or Nearctic-Neotropical migrants. We do not know the causes of the observed declines, nor can we conclude that these declines are not a purely local phenomenon. However, our findings, along with other recent reports of declines in these same species, suggest that a closer examination of their conservation status is warranted. Given the difficulty in obtaining spatially extensive, long-term estimates of population change for Hispaniolan birds, we suggest focusing on other metrics of vulnerability that are more easily quantified yet remain poorly described, such as extent of occurrence.

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Assessing conservation status of resident and migrant birds on Hispaniola with constant-effort mist-netting

10.7287/peerj.preprints.1368 ◽

2015 ◽

Author(s):

John D Lloyd ◽

Chris C Rimmer ◽

Kent P McFarland

Keyword(s):

Population Change ◽

Conservation Status ◽

Capture Rate ◽

Temporal Trends ◽

Bird Species ◽

Quantitative Information ◽

Neotropical Migrant ◽

Migrant Birds ◽

Conservation Assessments ◽

Capture Rates

We analyzed temporal trends in mist-net capture rates of resident (n = 8) and overwintering Nearctic-Neotropical migrant (n = 3) bird species at two sites in montane broadleaf forest of the Sierra de Bahoruco, Dominican Republic, with the goal of providing quantitative information on population trends that could inform conservation assessments. We conducted sampling at least once annually during the winter months of January – March from 1997 – 2010. We found evidence of steep declines in capture rates for three resident species, including one species endemic to Hispaniola. Capture rate of Rufous-throated Solitaire (Myadestes genibarbis) declined by 3.9% per year (95% CL = 0%, 7.3%), Green-tailed Ground-Tanager (Microlegia palustris) by 6.8% (95% CL = 3.9%, 8.8%), and Greater Antillean Bullfinch (Loxigilla violacea) by 4.9% (95% CL = 0.9%, 9.2%). Two rare and threatened endemics, Hispaniolan Highland-Tanager (Xenolegia montana) and Western Chat-Tanager (Calyptophilus tertius), showed statistically significant declines, but we have low confidence in these findings because trends were driven by exceptionally high capture rates in 1997 and varied between sites. Analyses that excluded data from 1997 revealed no trend in capture rate over the course of the study. We found no evidence of temporal trends in capture rates for any other residents or Nearctic-Neotropical migrants. We do not know the causes of the observed declines, nor can we conclude that these declines are not a purely local phenomenon. However, our findings, along with other recent reports of declines in these same species, suggest that a closer examination of their conservation status is warranted. Given the difficulty in obtaining spatially extensive, long-term estimates of population change for Hispaniolan birds, we suggest focusing on other metrics of vulnerability that are more easily quantified yet remain poorly described, such as extent of occurrence.

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Evidence of avian-mediated long distance dispersal in American tardigrades

PeerJ ◽

10.7717/peerj.5035 ◽

2018 ◽

Vol 6 ◽

pp. e5035 ◽

Cited By ~ 10

Author(s):

Matthew J. Mogle ◽

Scott A. Kimball ◽

William R. Miller ◽

Richard D. McKown

Keyword(s):

Bird Species ◽

Distribution Patterns ◽

Long Distance Dispersal ◽

Long Distance ◽

Neotropical Migrant ◽

Grus Canadensis ◽

Sandhill Crane ◽

Migrant Birds ◽

North And South

Terrestrial tardigrades, commonly known as “water bears”, are part of a phylum of microscopic, aquatic invertebrates famous for cryptobiosis and space travel, but little is known about their modes of dispersal on Earth. Wind is assumed, but not truly demonstrated, to be the major method of global dispersal. Yet, some water bear distribution patterns cannot be explained by patterns of prevailing winds. Mammals and birds have been proposed as potential animal vectors. Importantly, most nearctic-neotropical migrant birds move north and south, with many crossing the equator, whereas prevailing winds move west to east or east to west but do not cross the equator. When multiplied by billions of birds over tens of millions of years, if the ectozoochory of tardigrades by birds is true then both regional and intercontinental patterns can be better explained. To test for the potential role of birds in tardigrade dispersal, the nests of 10 species for birds were examined. Seventy percent of nests were positive for tardigrades, demonstrating that some birds are in a position for transference. The carcasses of eight birds (six species) found dead from window strikes and a Sandhill Crane (Grus canadensis) found dead during routine surveys were also examined. Of the birds examined, 66% yielded tardigrades from two classes, three orders, and five species, including juveniles, adults, and eggs, suggesting that many bird species are potential vectors for many species of tardigrades. Our data support the hypothesis of avian-mediated long distance dispersal of tardigrades and provide evidence that further investigation is warranted.

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Estimating conservation metrics from atlas data: the case of southern African endemic birds

Bird Conservation International ◽

10.1017/s0959270916000307 ◽

2017 ◽

Vol 27 (3) ◽

pp. 323-336 ◽

Cited By ~ 10

Author(s):

ALAN T. K. LEE ◽

RES ALTWEGG ◽

PHOEBE BARNARD

Keyword(s):

Citizen Science ◽

Large Scale ◽

Population Change ◽

Conservation Status ◽

Bird Species ◽

Science Data ◽

Atlas Data ◽

Endemic Birds ◽

Change Metrics ◽

Threatened Status

SummaryThe robust assessment of conservation status increasingly requires population metrics for species that may be little-researched, with no prospect of immediate improvement, but for which citizen science atlas data may exist. We explore the potential for bird atlas data to generate population metrics of use in red data assessment, using the endemic and near-endemic birds of southern Africa. This region, defined here as South Africa, Lesotho and Swaziland, is home to a large number of endemic bird species and an active atlas project. The Southern African Bird Atlas Projects (SABAP) 1 and 2 are large-scale citizen science data sets, consisting of hundreds of thousands of bird checklists and > 10 million bird occurrence records on a grid across the subcontinent. These data contain detailed information on species’ distributions and population change. For conservationists, metrics that guide decisions on the conservation status of a species for red listing can be obtained from SABAP, including range size, range change, population change, and range connectivity (fragmentation). We present a range of conservation metrics for these bird species, focusing on population change metrics together with an associated statistical confidence metric. Population change metrics correlate with change metrics calculated from dynamic occupancy modelling for a set of 191 common species. We identify four species with neither international nor local threatened status, yet for which bird atlas data suggest alarming declines, and two species with threatened status for which our metrics suggest could be reconsidered. A standardised approach to deciding the conservation status of a species is useful so that charismatic or flagship species do not receive disproportionate attention, although ultimately conservation status of any species must always be a consultative process.

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Importance of getting the numbers right: quantifying the rapid and substantial decline of an abundant marsupial, Bettongia penicillata

Wildlife Research ◽

10.1071/wr12115 ◽

2013 ◽

Vol 40 (3) ◽

pp. 169 ◽

Cited By ~ 45

Author(s):

A. F. Wayne ◽

M. A. Maxwell ◽

C. G. Ward ◽

C. V. Vellios ◽

B. G. Ward ◽

...

Keyword(s):

Population Size ◽

Population Change ◽

Conservation Status ◽

Nest Density ◽

Population Declines ◽

Bettongia Penicillata ◽

Epbc Act ◽

Substantial Decline ◽

Endangered Status ◽

Capture Rates

Context A reliable measure of population size is fundamental to ecology and conservation but is often difficult to obtain. The woylie, Bettongia penicillata, provides an example where ‘getting the numbers right’ has important implications in verifying and quantifying the recent unexpected, rapid and substantial declines across much of its range. Initial estimates prompted a conservation-status upgrade for the species to Endangered by the Australian Government. The present paper constitutes the foundational paper addressing the first steps of a decline diagnosis framework intended to identify the causes of the recent declines. Aims To verify whether the declines in woylie trap-capture rates are representative of population change; better quantify the size of the largest woylie populations; and review what is understood about the ecology of the woylie and identify key knowledge gaps that may be relevant to identifying the causes of the recent declines. Methods Monitoring data from live-cage trapping (transects and grids), sandpads, woylie diggings and nest-density surveys and spotlighting were collated. Population measures derived from trapping data included capture rates, number of individuals, abundance estimates based on capture–mark–recapture modelling and density using spatially explicit capture–recapture models (SECR). Key results The declines in woylie trap-capture rates were verified as real population declines and corresponded closely with other measures of abundance derived from the same trapping data as well as with independent measures. A 95% decline occurred in the largest extant woylie populations (in the Upper Warren region, Western Australia) between 2002 and 2008. At a species level, woylies declined ~90% (1999–2006), from a peak of ~200 000 individuals in 1999. Conclusions An accurate formal conservation status is an important factor in promoting the conservation of a species. It is recommended that the woylie be considered for Critically Endangered status under the Australian EPBC Act. Implications Adequate and effective monitoring of species is critical to detecting and quantifying population changes in a timely manner. Having an accurate measure of population size can have a significant impact on the effectiveness of conservation and management efforts.

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An assessment of the distribution, population size and conservation status of the Santa Marta Foliage-gleaner Automolus rufipectus: a Sierra Nevada de Santa Marta endemic

Bird Conservation International ◽

10.1017/s0959270914000513 ◽

2015 ◽

Vol 25 (4) ◽

pp. 451-465 ◽

Cited By ~ 3

Author(s):

ESTEBAN BOTERO-DELGADILLO ◽

NICHOLAS BAYLY ◽

CAMILA GÓMEZ ◽

PAULO C. PULGARÍN-R. ◽

CARLOS ANDRÉS PÁEZ

Keyword(s):

Population Size ◽

Sierra Nevada ◽

Forest Cover ◽

Conservation Status ◽

Bird Species ◽

Environmental Niche ◽

Coffee Plantations ◽

Habitat Transformation ◽

Elevation Range ◽

Area Of Occupancy

SummaryThe Santa Marta Foliage-gleaner Automolus rufipectus is one of 19 endemic bird species found in the Sierra Nevada de Santa Marta (SNSM) in northern Colombia but until recently it was considered a sub-species of the Ruddy Foliage-gleaner Automolus rubiginosus. Consequently, published information on its distribution and ecology is lacking, and while it is classified as near- threatened, this designation was based on limited quantitative data. To improve our knowledge of the Santa Marta Foliage-gleaner’s geographical distribution, elevation range, population density, habitat use and conservation status, we analysed both historical and recent site locality records and carried out variable distance transects within forested habitats and shade coffee plantations. We modelled the environmental niche of the species and subsequently estimated its extent of occurrence and area of occupancy, as well as population size. Our results consistently showed that the distribution of the Santa Marta Foliage-gleaner is more restricted than previously considered, both geographically and by elevation (we redefine elevation range as 600–1,875 m). This suggests that the species is more at risk of habitat transformation and combined with our estimates of population size (< 10,000 individuals), it is likely that the species will be uplisted to a higher threat category. More positively, and contrary to published accounts, we found that approximately 40% of the species’ range lies within protected areas. Nevertheless, we recommend the implementation of strategies to maintain forest cover on the western flank of the SNSM and further research to better define the species’ habitat needs and population dynamics.

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Bird richness and composition in a Cerrado fragment in the State of São Paulo

Brazilian Journal of Biology ◽

10.1590/s1519-69842010005000001 ◽

2010 ◽

Vol 70 (2) ◽

pp. 243-254 ◽

Cited By ~ 11

Author(s):

LT Manica ◽

M Telles ◽

MM Dias

Keyword(s):

Conservation Status ◽

Bird Species ◽

Low Frequency ◽

Bird Community ◽

Sao Paulo ◽

The State ◽

São Paulo ◽

Conservation Area ◽

Tropical Regions ◽

Bird Richness

Bird species richness is an important measure for monitoring biodiversity changes. We analysed avifauna richness and composition in a 472 ha protected cerrado fragment and surroundings at Fazenda Canchim (RL-CPPSE), São Carlos, in the State of São Paulo (SP). We carried out 95.1 hours of observation (22 visits) at irregular intervals from May 2004 to December 2006. Qualitative surveys were done walking through tracks inside the fragment and on the roads at its edge. We recorded 160 species, six of which were endemic to Cerrado domain, 22 migratory, seven threatened within the State of São Paulo, and two globally threatened. We found 28 species in the cerradão, 110 in the cerrado sensu stricto, 13 in the gallery forest, 26 in the reservoir border, 26 in pasturelands and sugar cane monoculture and 55 in an anthropic area. Most of the species had low frequency of occurrence in all vegetation forms. Insectivores were the major trophic category (46.9%), which is typical in tropical regions, and it is also related to resource availability. Omnivores followed with 19.4%, granivores with 8.8% and frugivores with 7.5%. We conclude that, despite its size and conservation status, our study area has a remarkable bird community and must be considered as a priority conservation area to preserve bird species in Sao Paulo State.

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Identification of bird species and their conservation status in Tuti Island, Sudan

International journal of food science and agriculture ◽

10.26855/ijfsa.2019.10.001 ◽

2019 ◽

Vol 3 (4) ◽

Author(s):

Mutasim E. A ◽

◽

Tahani A. H ◽

Nasir Y. G ◽

Moneer S. M ◽

...

Keyword(s):

Conservation Status ◽

Bird Species

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Congruence between breeding and wintering biodiversity hotspots: A case study in farmlands of Western Poland

European Journal of Ecology ◽

10.2478/eje-2018-0014 ◽

2019 ◽

Vol 4 (2) ◽

pp. 75-83

Author(s):

Federico Morelli ◽

Zbigniew Kwieciński ◽

Piotr Indykiewicz ◽

Łukasz Jankowiak ◽

Paweł Szymański ◽

...

Keyword(s):

Species Richness ◽

Protected Areas ◽

Functional Diversity ◽

Conservation Status ◽

Bird Species ◽

Bird Community ◽

Bird Diversity ◽

Human Beings ◽

Complete Representation ◽

Evolutionary Distinctiveness

Abstract Farmland landscapes are recognized as important ecosystems, not only for their rich biodiversity but equally so for the human beings who live and work in these places. However, biodiversity varies among sites (spatial change) and among seasons (temporal change). In this work, we tested the hypothesis that bird diversity hotspots distribution for breeding is congruent with bird diversity hotspots for wintering season, focusing also the representation of protected areas for the conservation of local hotspots. We proposed a framework based on the use of species richness, functional diversity, and evolutionary distinctiveness to characterize avian communities. Although our findings show that the spatial distribution of local bird hotspots differed slightly between seasons, the protected areas’ representation was similar in both seasons. Protected areas covered 65% of the most important zones for breeding and 71% for the wintering season in the farmland studied. Functional diversity showed similar patterns as did bird species richness, but this measure can be most effective for highlighting differences on bird community composition. Evolutionary distinctiveness was less congruent with species richness and functional diversity, among seasons. Our findings suggest that inter-seasonal spatial congruence of local hotspots can be considered as suitable areas upon which to concentrate greater conservation efforts. However, even considering the relative congruence of avian diversity metrics at a local spatial scale, simultaneous analysis of protected areas while inter-seasonally considering hotspots, can provide a more complete representation of ecosystems for assessing the conservation status and designating priority areas.

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Nepal’s National Red List of Birds

Journal of Threatened Taxa ◽

10.11609/jott.2855.9.1.9700-9722 ◽

2017 ◽

Vol 9 (1) ◽

pp. 9700 ◽

Cited By ~ 2

Author(s):

Carol Inskipp ◽

Hem Sagar Baral ◽

Tim Inskipp ◽

Ambika Prasad Khatiwada ◽

Monsoon Pokharel Khatiwada ◽

...

Keyword(s):

Endangered Species ◽

Biological Diversity ◽

Conservation Status ◽

Bird Species ◽

Convention On Biological Diversity ◽

Wetland Birds ◽

Distribution Maps ◽

Critically Endangered Species ◽

Passerine Species ◽

Over Exploitation

The main objectives of the Nepal National Bird Red Data Book were to provide comprehensive and up-to-date accounts of all the bird species found in Nepal, assess their status applying the IUCN Guidelines at Regional Levels, identify threats to all bird species and recommend the most practical measures for their conservation. It is hoped that the Bird RDB will help Nepal achieve the Convention on Biological Diversity target of preventing the extinction of known threatened species and improving their conservation status. As population changes of Nepal’s birds have been studied for only a few species, assessments of species’ national status were mainly made by assessing changes in distribution. Species distribution maps were produced for all of Nepal’s bird species except vagrants and compared to maps that were produced in 1991 using the same mapping system. Of the 878 bird species recorded, 168 species (19%) were assessed as nationally threatened. These comprise 68 (40%) Critically Endangered species, 38 (23%) Endangered species and 62 (37%) Vulnerable species. A total of 62 species was considered Near Threatened and 22 species Data Deficient. Over 55% of the threatened birds are lowland grassland specialists, 25% are wetland birds and 24% tropical and sub-tropical broadleaved forest birds. Larger birds appear to be more threatened than smaller birds with 98 (25%) non-passerine species threatened and 67 (14%) passerine species. Habitat loss, degradation and fragmentation are the most important threats. Other threats include chemical poisoning, over-exploitation, climate change, hydropower, invasive species, intensification of agriculture, disturbance, and limited conservation measures and research. Measures to address these threats are described. It was also concluded that re-assessments of the status of certain bird groups carried out every five years and the setting up of a national online system for storing and reporting bird sightings would be useful.

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